Note: Descriptions are shown in the official language in which they were submitted.
P2510CA01
DOOR CLOSER WITH SELF-POWERED CONTROL UNIT
DESCRIPTION
Background Art
This patent application claims priority from U.S. Patent Applications having
serial numbers 12/761,589, 12/761,599, 12/761,609, 12/761,633, 12/761,653, and
12/761,668 all filed on April 16, 2010.
Door closers are used to automatically close doors; hold doors open for short
intervals, and control opening/closing speeds in order to facilitate passage
through a
doorway and to help ensure that doors are not inadvertently left open. A door
closer
is often attached to the top or bottom of a door, and when the door is opened
and
released, the door closer generates a mechanical force that causes the door to
automatically close without any user input. Thus, a user may open a door and
pass
through its doorway without manually closing the door.
Many conventional door closers are designed to apply varying forces to a door
as a function of the door angle (i.e., the angle at which the door is open).
In this
regard, when the door is first opened, the door closer is designed to generate
a
relatively small force, which tends to push the door closed, so that the door
closer
does not generate significant resistance to the user's efforts to open the
door.
However, as the door is further opened thereby increasing the door angle,
greater
force is applied to the door by the door closer at various predefined door
angles.
Many conventional door closers are mechanically actuated and have a
plurality of valves and springs for controlling the varying amounts of force
applied to
the door as a function of door angle, as described above. A typical door
closer may
also have a piston that moves through a reservoir filled with a hydraulic
fluid, such as
oil. Adjusting the valve settings in such a conventional door closer can be
difficult
and problematic since closing times and forces can vary depending on
temperature,
pressure, wear and installation configuration. Moreover, adjusting the valve
settings
in order to achieve a desired closing profile for a door can be burdensome for
at least
some users. Many door closers exhibit much less than ideal closing
characteristics
because users are either unwilling or unable to adjust and re-adjust the valve
settings
in a desired manner or are unaware that the settings can be changed in order
to
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effectuate a desired closing profile in the face of temperature changes, wear
over time
and/or modifications to the physical installation.
Disclosure of Invention
Embodiments of the present invention include a door closer that is self
powered and includes a control unit to intelligently control a valve within
the door
closer to vary the operating characteristics of the door closer as needed. The
control
unit may also be referred to herein as a controller. In some embodiments, the
door
closer includes a spring and a movable element that loads the spring and is
also
configured to move in response to movement of the door. The valve is
configured to
control movement of hydraulic fluid around the movable element to very the
operating characteristics of the door closer. Various operating
characteristics of the
door closer can be varied. These operating characteristics include latch
region
parameters for the door such as the force with which the door in the latch
region and
where the latch region occurs in the swing of the door.
The control unit can include a teach mode that can be invoked at installation
time, or any other time, so that appropriate information can be stored in
memory
regarding an installation configuration, relative jamb position, swing (right
or left
handed) and other parameters. In some embodiments, the controller includes a
user
interface used to determine an installation configuration for the door closer
when the
controller is in teach mode, or at any other time. The position of the door
can be
monitored as the door moves in order to determine a swing for the door.
In some embodiments, the controller further includes a sprocket
interconnected with the chain, and a gear box gear connected to the sprocket
to
distribute angular rotational torque to prevent reverse torque from inhibiting
the
movement of the door. In some embodiments, the door closer hardware can be
calibrated by determining a plurality of arm positional values being output by
an arm
encoder coupled to an arm of the door closer, where each arm positional value
corresponds to an angular position of the arm. These values can be read in
response
to a user moving the arm, or in response to an automated calibration system
moving
the arm. The motor that controls the valve in the closer can also be activated
to move
the valve in the door closer to a plurality of positions, and the position
value output by
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an encoder for the valve position can be determined. The positional values
from the
encoders and the positions that they indicate can then be stored in a memory
within
the controller for use during normal operation of the door closer.
In some embodiments, the controller includes a position sensor to determine a
position of the door, and at least one input switch to enable user selection
of at least
one door closer parameter for an installed door closer. Control circuitry
includes a
connection for a motor to control the valve in the door closer. The control
circuitry is
operable to set the valve in response to the user selection of the door closer
parameters, and the position of the door, in order to control force exerted by
the door
closer on the door. A generator or a battery holder can be provided to provide
electricity to power the controller. In the case of a battery holder, a
battery would
need to be installed for the door closer to operate.
Brief Description of the Drawings
For a more complete understanding of the present invention, reference should
now be had to the embodiments shown in the accompanying drawings and described
below. In the drawings:
FIG. 1 is cut-away perspective view of an embodiment of a door closer
assembly in position on a door.
FIG. 2 is an exploded perspective view of the door closer assembly shown in
FIG. I.
FIG. 3 is an exploded perspective view of an embodiment of a door closer for
use with the door closer assembly shown in FIG. I.
FIG. 4 is an end view of the assembled door closer assembly as shown in FIG.
1.
FIG. 5A is a longitudinal cross-section view of the assembled door closer
assembly taken along line 5-5 of FIG. 4 with the door in a closed position.
FIG. 5B is a close-up view of a portion of the assembled door closer assembly
as shown in FIG. 5.
FIG. 6 is a longitudinal cross-section view of the assembled door closer
assembly taken along line 6-6 of FIG. 4 with the door in a closed position.
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FIG. 7 is a longitudinal cross-section view of the assembled door closer
assembly as shown in FIG. 5 with the door in an open position.
FIG. 8 is an exploded perspective view of an embodiment of a valve assembly
for use with the door closer as shown in FIG. 3.
FIG. 9 is an inner end view of the assembled valve assembly as shown in FIG.
8.
FIG. 10 is an outer end view of the assembled valve assembly as shown in
FIG. 8.
FIG. 11 is a longitudinal cross-section view of the valve assembly taken along
line 11-11 of FIG. 9.
FIG. 12 is a longitudinal cross-section view of the valve assembly taken along
line 12-12 of FIG. 9.
FIGs. 13A and 13B are transverse cross-section views of the valve assembly
taken along line 13-13 of FIG. 10 with the valve in a closed position.
FIG. 13C is a close-up view of a portion of the valve shaft and valve sleeve
in
a position shown in FIGs. 13A and 13B.
FIGs. 14A and 14B are transverse cross-section views of the valve assembly
taken along line 14-14 of FIG. 10 with the valve in an open position.
FIG. 15 is a longitudinal cross-section view of the valve assembly taken along
line 15-15 of FIG. 10.
FIG. 16 is a perspective view of an embodiment of a drive unit for use with
the door closer assembly as shown in FIG. 1.
FIG. 17 is an exploded perspective view of the drive unit as shown in FIG. 16.
FIG. 18 is a perspective view of the drive unit as shown in FIG. 16 with the
cover removed.
FIG. 19 is a perspective view of the drive unit as shown in FIG. 18 with the
COS 164 coupler removed.
FIG. 20 is a partially exploded perspective view of the drive unit as shown in
FIG. 19 with the mounting bracket removed.
FIG. 21 is a front plan view of an embodiment of a motor coupler for use with
the drive unit as shown in FIG. 16.
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FIG. 22 is an elevated perspective view of an embodiment of a COS 164
coupler operatively connected to the motor coupler as shown in FIG. 21.
FIG. 23 is a perspective view of an embodiment of a rotatable motor cover for
use with the drive unit as shown in FIG. 16.
FIG. 24 is a partial view of a cross-section of the drive unit as shown in
FIG.
16 taken along line 24-24 of FIG. 23.
FIG. 25 is perspective view of an inner surface of an embodiment of a PCB
board for use with the drive unit as shown in FIG. 16.
FIG. 26 is a partial perspective end view of the assembled door closer
assembly as shown in FIG. 1 with the motor cover removed.
FIG. 27 is a partial perspective end view of the assembled door closer
assembly as shown in FIG. 26 with another embodiment of a motor cover.
FIG. 28 is a perspective view of an embodiment of a control unit for use with
the door closer assembly as shown in FIG. I.
FIG. 29 is an exploded perspective view of the control unit as shown in FIG.
28.
FIG. 30 is a block diagram of an embodiment of a printed circuit board for use
in a control unit for controlling a valve of a door closer.
FIG. 31 is a partially exploded perspective view of a portion of the control
unit
as shown in FIG. 29.
FIG. 32 is an exploded bottom perspective view of an embodiment of a power
generator portion of the control unit as shown in FIG. 29.
FIG. 33 is an exploded top perspective view of the power generator portion of
the control unit as shown in FIG. 32.
FIG. 34 is a partial bottom plan view of the power generator portion of the
control unit as shown in FIG. 32.
FIG. 35 is a longitudinal cross-section view of the power generator taken
along line 35-35 of FIG. 34.
FIG. 36 is partial top plan view of the power generator portion of the control
unit as shown in FIG. 32.
FIG. 37 is a longitudinal cross-section view of the power generator taken
along line 37-37 of FIG. 36.
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FIG. 38 is a partially exploded perspective view of an embodiment of an
encoder portion of the control unit as shown in FIG. 29.
FIG. 39 is an exploded top perspective view of the encoder portion of the
control unit shown in FIG. 29.
FIGs. 40A and 40B are bottom and top perspective views, respectively, of an
embodiment of a drive gear for use with the control unit as shown in FIG. 29.
FIG. 41 is an embodiment of a circuit diagram for providing power to various
electrical components of a door closer.
FIG. 42 is partial top plan view of the encoder portion of the control unit as
shown in FIG. 28.
FIG. 43A is a longitudinal cross-section view of the encoder portion of the
control unit taken along line 43-43 of FIG. 42 with a teach button in a first
position.
FIG. 43B is a longitudinal cross-section view of the encoder portion of the
control unit taken along line 43-43 of FIG. 42 with the teach button in a
second
position.
FIG. 44 is a flow diagram of an embodiment of a process for using a teach
mode of a door closer, presented as FIGs. 44A, 44B and 44C.
FIG. 45 is a diagram of a calibration curve.
FIG. 46 is a diagram of a motor encoder calibration curve.
FIG. 47 is a flow diagram of an embodiment of a process for arm encoder
calibration, presented as FIGs. 47A and 47B.
FIG. 48 is a flow diagram of an embodiment of a process for calibration of a
valve encoder with respect to valve position, presented as FIGs. 48A, 48B and
48C.
FIG. 49 is a flow diagram of an embodiment of a process for operating a
controller, presented as FIGs. 49A, 49B, 49C, 49D', 49D", 49E', 49E", 49F' and
49F".
FIG. 50 is a perspective end view of a portion of a control unit including an
embodiment of user input switches.
Best Mode(s) for Carrying Out the Invention
Terminology used herein is for the purpose of describing particular
embodiments only and is not intended to be limiting of the invention. As used
herein,
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the singular forms "a", "an" and "the" are intended to include the plural
forms as well,
unless the context clearly indicates otherwise. It will be further understood
that the
terms "comprises" or "comprising," when used in this specification, specify
the
presence of stated features, steps, operations, elements, or components, but
do not
preclude the presence or addition of one or more other features, steps,
operations,
elements, components, or groups thereof. Additionally, comparative,
quantitative
terms such as "above", "below", "less", "greater", are intended to encompass
the
concept of equality, thus, "less" can mean not only "less" in the strictest
mathematical
sense, but also, "less than or equal to."
It should also pointed out that references made in this disclosure to figures
and
descriptions using positional terms such as, but not limited to, "top",
"bottom",
"upper," "lower," "left", "right", "behind", "in front", "vertical",
"horizontal",
"upward," and "downward", etc., refer only to the relative position of
features as
shown from the perspective of the reader. Such terms are not meant to imply
any
absolute positions. An element can be functionally in the same place in an
actual
product, even though one might refer to the position of the element
differently due to
the instant orientation of the device. Indeed, the components of the door
closer may
be oriented in any direction and the terminology, therefore, should be
understood as
encompassing such variations unless specified otherwise.
As used herein, the term "open position" for a door means a door position
other than a closed position, including any position between the closed
position and a
fully open position as limited only by structure around the door frame, which
can be
up to 180 from the closed position.
The present disclosure generally relates to systems and methods for
controlling of door closers. For example, the door closer may be controlled so
that
when a first predefined door angle such as, for example, 50 degrees is
reached, the
door closer increases the force applied to the door. The force applied to the
door as
the door is opened wider may remain substantially constant until another
predefined
angle such as, for example, 70 degrees is reached, at which point an even
greater force
is applied to the door. The force may be similarly increased for other
predefined door
angles. As the door angle increases or, in other words, as the door is opened
wider, it
generally becomes more difficult to continue pushing the door open. Such a
feature
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helps to prevent the door from hitting a door stop or other object, such as a
wall, with
a significant force thereby helping to prevent damage to the door or the
object hit by
the door.
When the door is released by the user, the force generated by the door closer
begins to push the door closed. As the door reaches the predefined angles
described
above, the force applied to the door decreases. Thus, initially, when the door
has been
opened wide, there may be a relatively significant force applied to the door,
thereby
helping to start moving the door to the closed position. However, at each
predefined
angle, the force applied to the door by the door closer decreases. Thus, as
the door
angle decreases or, in other words, as the door is closing, the force applied
to the door
generally decreases as a function of door angle. Indeed, by the time the door
is about
to fully close, the force applied to the door is sufficiently small to prevent
damage to
the door when the door contacts the door frame. Further, having a relatively
small
amount of force applied to the door at small door angles helps to prevent
injury to a
user in the event that a finger, arm, foot, or other body part is struck by
the door as the
door closes.
In one embodiment, a door closer has a valve that is electrically actuated
such
that the position of the valve can be dynamically changed during operation.
Thus, as
a door opens and closes, the valve position can be changed in order to provide
varying
levels of hydraulic resistance as a function of door angle, so that only one
valve is
strictly necessary to provide such varying levels of resistance. Further, a
desired
closing profile can be reliably and precisely implemented without a user
having to
manually adjust the positions of a plurality of valves.
Referring now to the drawings, wherein like reference numerals designate
corresponding or similar elements throughout the several views, a door closer
assembly according to the present invention is shown and generally designated
at 80.
Referring to FIG. 1, the door closer assembly 80 is mounted to a door 82 in a
door
frame 84. The door 82 is movable relative to the frame 84 between a closed
position
and an open position. For the purpose of this description, only the upper
portion of
the door 82 and the door frame 84 are shown. The door 82 is of a conventional
type
and is pivotally mounted to the frame 84 for movement from the closed
position, as
shown in FIG. I, to an open position for opening and closing an opening
through a
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building wall 86 to allow a user to travel from one side of the wall to the
other side of
the wall.
As shown in FIGS. 1 and 2, an embodiment of a door closer assembly 80
comprises a door closer 90, including a linkage assembly 92 for operably
coupling the
door closer assembly 80 to the door frame 84, a drive unit 100, and a control
unit 110.
As seen in FIG. 2, ends of a rotating pinion 112 extend from the top and
bottom of the
door closer 90 for driving the linkage assembly 92 to control the position of
the door
82. FIG. 1 shows a linkage assembly 92 for a push side mounting of the door
closer
assembly 80 to the door 82, comprising a first rigid connecting arm link 94
and a
second rigid connecting arm link 96. The first connecting arm link 94 is fixed
at one
end for rotation with the upper end of the pinion 112 (FIG.1) and at the other
end is
pivotally connected to an end of the second connecting arm link 96. The other
end of
the second connecting arm link 96 is pivotally joined to a mounting bracket 98
fixed
to the door frame 84. A linkage assembly for a pull side mounting (not shown)
of the
door closer assembly 80 to the door 82 is also suitable. Both push side and
pull side
mounting of the linkage assemblies are well known in the art. Further, it
should be
understood that the linkage assembly 92 for use in the present invention may
be any
arrangement capable of linking the door closer 90 to the door 82 in such a
manner that
the door closer assembly 80 affects movement of the door 82. Thus, numerous
alternative forms of the linkage assembly 92 may be employed.
The door closer assembly 80 is securely mounted to the upper edge of the door
82 using mounting bolts (not shown), or other fasteners. The door closer
assembly 80
extends generally horizontally with respect to the door 82. The drive unit 100
and the
control unit 110 are fixed to the door closer 90. A cover (not shown) attaches
to the
door closer assembly 80. The cover serves to surround and enclose the
components
of the door closer assembly 80 to reduce dirt and dust contamination, and to
provide a
more aesthetically pleasing appearance. It is understood that although the
door closer
assembly 80 is shown mounted directly to the door 82, the door closer assembly
80
could be mounted to the door frame 84 or to the wall adjacent the door frame
84 or
concealed within the wall 86 or the door frame 84. Concealed door closer
assemblies
are well known in the art of automatic door closer assemblies.
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The door closer 90 is provided for returning the door 82 to the closed
position
by providing a closing force on the door 82 when the door is in an open
position. The
door closer 90 includes an internal return spring mechanism such that, upon
rotation
of the pinion 112 during door 82 opening, the spring mechanism will be
compressed
for storing energy. As a result, the door closer 90 will apply on the linkage
assembly
92 a moment force which is sufficient for moving the door 82 in a closing
direction.
The stored energy of the spring mechanism is thus released as the pinion 112
rotates
for closing the door 82. The closing characteristics of the door 82 can be
controlled
by a combination of the loading of the return spring mechanism and the
controlled
passage of fluid through fluid passages between variable volume compartments
in the
door closer housing, as described more fully below.
FIGs. 3-7 depict an embodiment of the door closer 90. The door closer 90
comprises a housing 114 defining an internal chamber which is open at both
ends.
The chamber accommodates the pinion 112, a piston 116, a spring assembly 118,
and
a valve assembly 120. The housing 114.
The pinion 112 is an elongated shaft having a central gear tooth portion 122
bounded by intermediate cylindrical shaft portions 124. The pinion 112 is
rotatably
mounted in the door closer housing 114 such that the pinion 112 extends normal
to
the longitudinal axis of the housing 114. The intermediate cylindrical shaft
portions
124 of the pinion 112 are rotatably supported in bearings 126 each held
between an
inner washer 128 and an outer retaining ring 130 disposed within opposed
annular
bosses 132 formed on the top surface and the bottom surface of the housing
114. The
outer ends of the shaft of the pinion 112 extend through the openings in the
bosses
132 and outwardly of the housing 114. The ends of the pinion 112 are sealed by
rubber u-cup seals 134 which fit over the ends of the pinion 112 and prevent
leakage
of a hydraulic working fluid from the chamber of the housing 114. The
periphery of
the bosses 132 are externally threaded for receiving internally threaded
pinion seal
caps 136.
The spool-shaped piston 116 is slidably disposed within the chamber of the
housing 114 for reciprocal movement relative to the housing 114. In this
arrangement, as shown in the FIGs. 5-7, the piston 116 divides the chamber in
the
housing 114 into a first variable volume chamber 148 between one end of the
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116 and the valve assembly 120 and a second variable volume chamber 150
between
the other end of the piston 116 and the spring assembly 118. The central
portion of
the piston 116 is open and defines opposed rack teeth 117. The pinion 112 is
received
in the open central portion of the piston 116 such that the gear teeth 122 on
the pinion
112 engage the rack teeth 117 in the piston 116. It is thus understood that
rotation of
the pinion 112 will cause linear movement of the piston 116 by interaction of
the gear
teeth 122 and the rack teeth 117 in a conventional manner known in the art.
The spring assembly 118 comprises two compression springs 138, one nested
inside the other and supported between the piston 116 and an end plug assembly
140.
The end plug assembly 140 includes an end plug 142, an adjusting screw 144,
and a
retaining ring 146. The end plug 142 is an externally threaded disc sealingly
secured
in the threaded opening in the end of the housing 114. The end plug 142 is
sealed to
the wall of the housing 114 with the retaining ring 146 disposed in a
circumferential
groove on the periphery of the end plug 142. The end plug 142 thus effectively
seals
the end of the housing 114 against leakage of fluid. The adjusting nut 144 is
held in
the housing 114 between the springs 138 and the end plug 142. The springs 138
urge
the piston 116 towards the left end of the housing 114, as seen in FIGs. 5-7.
The
adjusting nut 144 is accessible by tool from the end of the housing 114, and
rotating
the adjusting nut 144 sets the initial compressed length of the springs 138.
A fluid medium, such as hydraulic oil, is provided in the chamber in the
housing 114 to cooperate with the piston 116. The end of the piston 116
adjacent the
first variable volume chamber 148 includes a centrally located check ball
assembly
152 and has a circumferential groove for accommodating a u-cup seal 154 which
seats
against the inside wall of the housing 114. The other end of the piston 116
adjacent
the second variable volume chamber 150 is closed and sealed relative to the
inside
wall of the housing 114 to prevent passage of fluid, except in the area of a
longitudinal groove 156 (FIG. 5A) of pre-determined length in the inside wall
of the
housing 114.
The valve assembly 120 is sealingly disposed in the opening in the end of the
housing 114 adjacent the piston 116. Referring to FIGs. 8-15, the valve
assembly 120
comprises a valve housing 160, a valve sleeve 162, a valve shaft 164 and a
spool plate
166. The valve housing 160 is a cylindrical member including a relatively
short
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cylindrical axial projection 168 at an outer end. The valve housing 160
defines a
central axial opening 170 therethrough. The outer end of the valve housing 160
defines a portion of the opening 161 having a smaller diameter than the
remainder of
the opening thereby forming a shoulder 171 (FIGs. 11, 12 and 15) in the axial
opening
170 adjacent the outer end of the valve housing 160. The inner end of the
valve
housing 160 has six spaced axial bores 172, 174, 176, 178 in the inner surface
of the
valve housing. Three equally spaced bores 172 are threaded screw holes for
receiving
screws 173 for securing the spool plate 166 to the valve housing 160. The
remaining
three bores 174, 176, 178 are fluid passages. Spaced circumferential grooves
180 are
provided in the periphery of the valve housing 160 for receiving o-rings 182.
The
grooves 180 define an intermediate circumferential surface onto which radial
passages
184, 186, 188, 190, 192 open (FIGs. 13 and 14). Four of the radial passages
184, 186,
188, 190 are drilled through to the central axial opening 170.
The cylindrical valve sleeve 162 fits into the axial opening 170 in the valve
housing 160. The valve sleeve 162 defines a central axial opening 163
therethrough.
The valve sleeve 162 has four equally, circumferentially spaced radial
openings 194
opening into the central axial opening 163. The valve sleeve 162 has a second
smaller
axial passage 196 therethrough (FIG. 15). A small radial bore 198 in the
periphery of
the valve sleeve 162 connects to the second axial passage 196. The valve
sleeve 162
fits into the valve housing 160 such that each of the radial openings 194 is
aligned
with one of the pass through radial openings 184, 186, 188, 190 in the valve
housing
160. As best seen in FIG. 11, one corresponding set of the openings 188, 194
in the
housing 160 and sleeve 162 is sized to receive a hollow pin 200 for locking
the valve
sleeve 162 to the valve housing 160.
The cylindrical valve shaft 164 is joumaled inside the valve sleeve 162. The
outer end of the valve shaft 164 carries a cut off screw 202 with a square
end.
Opposed partial circumferential grooves 204, 205 are provided intermediate the
ends
of the valve shaft 164. The valve shaft 164 is configured such that when the
valve
shaft 164 is disposed inside the valve sleeve 162, the grooves 204, 205 are at
the same
relative axial position as the radial openings 194 in the valve sleeve 162.
The spool plate 166 is attached to the inner surface of the valve housing 160
using screws 173 threaded into the three passages 172 in the valve housing 160
for
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holding the valve sleeve 162 in place. The inner surface of the spool plate
166 has a
depression 206 (FIG. 15) which is aligned with the second axial passage 196 in
the
valve sleeve 162 when the spool plate 166 is secured to the valve housing 160
for
fluid transfer during high pressure situations, as will be described below.
The valve assembly 120 fits into the end of the housing 114 (FIGs. 3, 5-7).
Each of the outer surface of the valve housing 160 and the end of the housing
114 has
a depression 208 for receiving an anti-rotation tab 210. An externally
threaded disc
212 and o-ring 214 is secured in an internally threaded opening in the end of
the
housing 114. The cut-off screw 202 on the valve shaft 164 rotatably extends
through
a central hole in the disc 212 and is held in place by the disc. As seen in
FIGs. 5-7, a
circumferential groove 216 is provided in the housing 114. With the valve
assembly
120 in place, the groove 216 is disposed between the o-rings 182 for forming a
fluid
path around the periphery of the valve housing 160 defined by the periphery of
the
valve housing between the o-rings 182 and the inner surface of the housing 114
defining the groove 216.
As seen in FIG. 6, the housing 114 is provided with a passage 218 through
which fluid is transferred during reciprocal movement of the piston 116 in the
chamber for regulating movement of the door 82. The fluid passage 218 runs
longitudinally between a radial passage 220 in the housing 114 opening into
the end
of the housing 114 adjacent the valve assembly 120 to a radial passage 222 in
the
housing 114 opening into the chamber adjacent the spring assembly 118. The
passage
218 thus serves as a conduit for fluid to pass between the first variable
volume
chamber 148 on one side of the piston 116 and the second variable volume
chamber
150 on the other side of the piston 116.
When the door 82 is in the fully closed position, the components of the door
closer 90 according to the present invention are as shown in FIG. 5. As the
door 82 is
opened, the door rotates the pinion 112 and thereby advances the piston 116
linearly
to the right as seen in FIGs. 6 and 7. Movement of the piston 116, in turn,
compresses
the springs 138 between the piston 116 and the end plug 142. It is understood
that the
door closer assembly 80 can be used on a left hand door or a right hand door
and,
therefore, the door could be opened in a either a clockwise or a
counterclockwise
direction.
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As the piston 116 moves toward the right end of the chamber in the housing
114, the fluid surrounding the springs 138 is forced through the radial
passage 222
and into the longitudinal fluid passage 218. The fluid passes through the
radial
passage 220 at the end of the housing 114 adjacent the valve assembly 120 and
into
the groove 216 in the housing 114. Fluid thus surrounds the central portion of
the
valve housing 160 between the o-rings 182 such that the opposed radial bores
184,
188 in the valve housing 160 are in fluid communication with the main fluid
passage
218 through the housing 114 (FIG. 6). The fluid flows into the radial passages
184,
188 in the valve housing 160 and the through the corresponding openings 194 in
the
valve sleeve 162 toward the valve shaft 164. If the valve shaft 164 is in a
closed
position (FIG. 13), the fluid cannot advance because the valve shaft 164
covers the
openings to the other radial passages. If the valve shaft 164 is rotated to an
open
position, such that a flow path exists between the radial passages as shown in
FIG. 14,
the fluid can flow to the radial passages 186, 190 in the valve housing 160
and to the
axial passages 174, 176 which open into the first variable volume chamber 148.
The degree of rotation of the valve shaft 164 relative to the valve sleeve 162
regulates the rate of fluid flow past the valve shaft 164 and, thus, the speed
of
movement of the opening door 82. As shown in FIGs. 8 and 13C, a small portion
of
material is removed adjacent each groove 204, 205 on the valve shaft 164,
forming
partial circumferential slots 224, 226 of increasing depth. The slots 224, 226
are
positioned such that the valve shaft 124 must rotate about seven degrees
before the
vertex of each slot 224, 226 intersects the corresponding radial exit passages
194 in
the valve sleeve 162. However, there may be some leakage around the valve
shaft
164 causes some fluid transfer before the valve shaft 164 rotates the full
seven
degrees and begins to uncover the passages 194. The full length of the slots
224, 226
from vertex to end may account for about fifteen degrees of rotation of the
valve shaft
164 relative to the valve sleeve 162.
The slots 224, 226 function to provide more resolution in controlling door
movement. Moreover, as fluid temperature increases, full movement of the door
82
may be accomplished while the valve shaft 164 rotates only within the range
provided
by the slots 224, 226. It is understood that, as the temperature of the fluid
decreases,
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the valve shaft 164 may be required to open further for providing a larger
area for
fluid flow for equivalent fluid transfer.
Referring to FIGs. 5 and 5A, another path through the piston 116 is provided
for moving fluid from the second variable volume chamber 150 to the first
variable
volume chamber 148 during door 82 opening. As the piston 116 moves to the
right
away from the valve assembly 120 and fluid enters the first variable volume
chamber
148, the ball of the check ball assembly 152 in the end of the piston 116
unseats and
fluid is forced around the closed end of the piston 116, through the opening
defined
by the check ball assembly 152 and into the first variable volume chamber 148.
Fluid
flows freely until the closed end of the piston 116 passes the end of the
groove 156.
Because the end of the piston 116 adjacent the second variable volume chamber
150
is closed and sealed relative to the inside wall of the housing 114, flow of
fluid
bypassing the piston 116 stops. This may occur, for example, where the door 82
reaches a back check region or position, as described herein. In general,
providing for
fluid flow past the piston 116 allows a smooth transition when the door
initially
begins to move to an open position from a stop, or when the door is moving in
a
closing direction and there is a sudden change to moving in the opening
direction.
Less power is required to change the position of the valve shaft 164 under
these
conditions.
When the door 82 reaches a fully open position, the piston 116 is in the
position shown in FIG. 7 and the springs 89 are compressed.
Movement of the door 82 from an open position to the closed position is
effected by expansion of the springs 138 acting to move the piston 116 to the
left as
seen in FIGs. 5-7. The advancing piston 116 causes the pinion 112 to rotate
for
moving the door 82 toward the closed position. Fluid pressure in the first
variable
volume chamber 148 created by the piston 116 moving toward the valve assembly
120 forces the ball in the ball check assembly 152 against its seat preventing
fluid
flow through the piston 116. Fluid is then forced out of the first variable
volume
chamber 148 in the housing 114, through the valve assembly 120, and the
housing
passages 218, 220, 222 and into the second variable volume chamber 150 around
the
springs 138. Specifically, the fluid initially flows into the axial passages
174, 176 and
then to the corresponding radial passages 186, 190 to the valve shaft 164. If
the valve
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shaft 164 is in the closed position (FIG. 13), the fluid cannot advance. If
the valve
shaft 164 is rotated to an open position, such as shown in FIG. 14, the fluid
exits via
the grooves 204, 205 and slots 224, 225 of the valve shaft 164, the radial
openings
194 in the valve sleeve 162, and into the radial passages 184, 188 in the
valve housing
160 toward the housing passages 218, 220, 222. Fluid again surrounds the
central
portion of the valve housing 160 between the o-rings 182 and exits through the
housing passage 220. The degree of rotation of the valve shaft 164 relative to
the
valve sleeve 162 will affect the rate of fluid flow past the valve shaft 164
and, thus,
the speed of movement of the closing door 82. When the door 82 reaches the
closed
position, the components of the door closer 90 are again as shown in FIG. 5.
In general, the fluid path in the arrangement described herein, provides for a
balance of forces on the valve assembly 120. Specifically, fluid surrounds the
central
portion of the valve housing 160 between the o-rings 182 and passes into the
valve
assembly 120 via opposed radial bores 184, 188. The opposed grooves 204, 205
and
slots 224, 226 provided on the valve shaft 164 also function to balance fluid
flow
through the valve and minimize side loading of the valve shaft 164, which
would
otherwise increase torque necessary to rotate the valve shaft 164.
As seen in FIG. 15, a radial vent passage 228 is provided in the valve housing
160 and is arranged in fluid communication with the radial bore 198 in the
valve
sleeve 162 which communicates with the axial vent passage 196. The openings to
the
vent passages 178, 228 in the valve housing 160 are counter-bored for
receiving check
balls 230, 232. The diameter of the balls 230, 232 are larger than a smaller
outer
diameter portion of the passages 178, 228 for allowing only one-way fluid
flow. This
arrangement of fluid passages serves as a vent relief in high pressure
situations.
Specifically, during door opening, if the pressure in the fluid flow path
becomes
excessive, the fluid pressure may force the ball 232 into the larger diameter
portion of
the axial passage 178 through the valve housing 160 so as to open the passage
allowing fluid flow through the passage 178. It is understood that fluid
pressure
forces the other ball 230 onto the smaller outer diameter of the corresponding
radial
passage 228 in the valve housing 160. Fluid surrounding the valve shaft 164
can exit
outwardly via the radial passage 198 in the valve sleeve 162 and the radial
passage
228 in the valve housing 160 and out the axial vent passage 178 in the valve
housing
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160 and into the first variable volume chamber 148 via a hole 234 in the spool
plate
166 (FIG. 10). During door closing, if the pressure in the fluid flow path
becomes
excessive, the fluid pressure may force the ball 230 into the larger diameter
portion of
the passage 228 so as to open the passage allowing fluid flow through the
passage
228. It is understood that fluid pressure forces the other ball 232 onto the
smaller
outer diameter of the corresponding passage 178. Fluid surrounding the valve
shaft
164 will thus exit outwardly via the radial passage 198 in the valve sleeve
162 and
will continue outwardly through the radial vent passage 228 to the fluid flow
path
around the valve housing 160 in the groove 216 in the housing 114 and exits
via the
housing passages 218, 220, 222. The pressure venting prevents a U-cup seal in
the
valve assembly 120 from energizing and causing a dynamic braking effect on the
valve shaft 164. Thus, it is understood that the valve assembly 120 is
balanced during
operation by surrounding the valve housing 160 with fluid which flows via
passages
on opposite sides of the valve housing 160.
According to an embodiment of the door closer assembly 80, the position of
the valve shaft 164 may be dynamically changed during door movement for
controlling the flow of fluid past the valve shaft 164 and through the
passages. Thus,
as the door opens and closes, the valve position can be changed in order to
provide
varying levels of hydraulic resistance as a function of door angle. Fluid flow
is
controlled by powered rotational movement of the valve shaft 164, referred to
herein
as the "cut-off shaft (COS 164)". In this regard, many conventional valves
have a
screw, referred to herein as the "cut-off screw," that is used to control the
valve's
"angular position." That is, as the cut-off screw is rotated, the valve's
angular
position is changed. The valve's "angular position" refers to the state of the
valve
setting that controls the fluid flow rate through the valve. For example, for
valves that
employ a cut-off screw to control flow rate, the valve's "angular position"
refers to
the position of the cut-off screw. In this regard, turning the cut-off screw
in one
direction increases the valve's angular position such that the valve allows a
higher
flow rate through the valve. Turning the cut-off screw in the opposite
direction
decreases the valve's angular position such that the fluid flow through the
value is
more restricted (i.e., the flow rate is less). In one embodiment, the valve
assembly
120 is conventional having a cut-off screw 202 and the COS 164, or valve
shaft, is
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coupled to or integral with the cut-off screw 202 for controlling fluid flow
rate. Thus,
rotation of the cut-off screw 202 changes the angular position of the valve
shaft 164
and, therefore, affects the fluid flow rate.
The drive unit 100 is coupled to the cut-off screw 202 for rotating the valve
shaft 164 as appropriate to control the angular position of the valve shaft
164 in a
desired manner, as will be described in more detail below. Referring to FIGs.
16 and
17, the drive unit 100 comprises a COS 164 coupler 240, a motor coupler 242, a
motor 244, a mounting bracket 246, a PCB board 252, and a cover, including a
fixed
cap 248 and a rotating cap 250. As shown in FIGs. 17 and 18, the COS 164
coupler
240 includes a disc 254 with a hollow tab extension 256 positioned at a center
of the
disc 254. The tab 256 defines a hole 257 for receiving the cut-off screw 202.
The
central axis of the hole 257 is aligned with the central axis of rotation of
the disc 254.
The inner wall of the tab 256 is dimensioned such that the cut-off screw 202
fits
snugly into the tab 256 for fixed rotation of the cut-off screw 202 and the
COS 164
coupler 240 (FIGs. 5-7).
Referring to FIGs. 20 and 21, the motor coupler 242 is also a disc having a
hollow tab extension 258 positioned at a central axis of the motor coupler
242. The
tab 258 defines an opening 259 for receiving a motor shaft 260, which is
rotated by
the motor 244 under the direction and control of control logic as described
herein.
The inner wall of the tab 258 defining the opening 259 is dimensioned such
that the
motor shaft 260 fits snugly in the tab 258 for fixed rotation of the motor
shaft 260 and
the motor coupler 242. The motor coupler 242 has a second hollow tab extension
262
radially spaced from the first hollow tab extension 258. An axially extending
pin 255
is disposed in the second hollow tab extension 262. The inner wall of the tab
262 is
dimensioned such that the pin 255 fits snugly in the tab 262, and frictional
forces
generally keep the pin 255 stationary with respect to the motor coupler 242.
Therefore, any rotation of the motor coupler 242 moves the pin 255 about the
center
of the motor shaft 260. The motor coupler 242 has a third hollow tab extension
264
radially spaced from the second hollow tab extension 262. A magnet 266 is
disposed
in the third hollow tab extension 264. For example, in one exemplary
embodiment,
the magnet 266 is glued to the motor coupler 242, but other techniques of
attaching
the magnet 266 to the motor coupler 242 are possible in other embodiments. As
the
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motor coupler 242 rotates with the motor shaft 260, the pin 255 and the magnet
266
rotate about the central axis of rotation of the motor coupler 242.
Referring to FIGs. 18 and 22, the COS 164 coupler disc 254 has a slot 268
which receives the pin 255 on the motor coupler 242. The slot 268 is
dimensioned
such that its width (in a direction perpendicular to the r-direction) is
slightly larger
than the diameter of the pin 255 so that frictional forces do not prevent the
COS 164
coupler 240 from moving relative to the pin 255 in the y-direction, which is
parallel to
the centerline of the pin 255. Therefore, if the COS 164 coupler 240 receives
any
mechanical forces in the y-direction, such as forces from a user kicking or
slamming
the door 82 or from pressure of the fluid flowing in the valve assembly 120,
the COS
164 coupler 240 is allowed to move in the y-direction relative to the pin 255
thereby
preventing such forces from passing through the pin 255 to other components,
such as
the motor 244, coupled to the pin 255. Such a feature can help prevent damage
to
such other components and, in particular, the motor 244. In addition, as shown
by
FIG. 22, the radial length of the slot 268 in the r-direction is significantly
greater than
the diameter of the pin 255 such that it is unnecessary for the alignment
between the
couplers 240, 242 to be precise. Indeed, any slight misalignment of the
couplers 240,
242 simply changes the position of the pin 255 along a radius of the COS 164
coupler
240 without creating stress between the pin 255 and the COS 164 coupler 240.
That
is, slight misalignments between the COS 164 coupler 240 and the motor coupler
242
changes the location of the pin 255 in the r-direction. However, since the pin
255 can
move freely to at least an extent in the r-direction relative to the COS 164
coupler
240, such misalignments do not create stress in either of the couplers 240,
242.
In one exemplary embodiment, the width (perpendicular to the r-direction) of
the slot 268 is about equal to or just slightly larger than the width of the
pin 255.
Thus, the width of the slot 268 is small enough so that any rotation of the
motor
coupler 242 causes a corresponding rotation of the COS 164 coupler 240, but is
large
enough so that significant friction or other mechanical forces are not induced
by
movement of the COS 164 coupler 240 in the y-direction. Allowing the COS 164
coupler 240 to move relative to the motor coupler 242 in the y-direction not
only
prevents mechanical forces from transferring from the COS 164 coupler 240 to
the
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motor coupler 242, but also obviates the need to precisely set the separation
distance
between the couplers 240, 242.
The couplers 240, 242 can be made of various materials. In one embodiment,
the couplers 240, 242 may be composed of plastic, which is typically a low
cost
material. In addition, the size of the couplers can be relatively small. Note
that the
shapes of the couplers 240, 242, as well as the shapes of devices coupled to
such
components, can be changed, if desired. For example, the cross-sectional shape
of the
cut-off screw 202 may be circular; however, other shapes are possible. For
example,
the cross-sectional shape of the cut-off screw 202 could be a square or
rectangle. In
such an example, the shape of the hole 257 in the hollow tab extension 256 on
the
COS 164 coupler 240 may be a square or rectangle to correspond to the shape of
the
cut-off screw 202. In addition, the cross-sectional shape of the COS 164
coupler 240
is shown to be generally circular, but other shapes, such as a square or
rectangle are
possible. Similarly, the motor coupler 242 and the pin 255 may have shapes
other
than the ones shown explicitly in the FIGs.
In the embodiments described above, the pin 255 is described as being fixedly
attached to the motor coupler 242 but not to the COS 164 coupler 240. In other
embodiments, other configurations are possible. For example, it is possible
for a pin
255 to be fixedly coupled to the COS 164 coupler for rotation with the COS 164
coupler and thus movable relative to a motor coupler.
In addition, it should be further noted that it is unnecessary for the
couplers
240, 242 to rotate over a full 360 degree range during operation. In one
exemplary
embodiment, about a thirty-five degree range of movement is sufficient for
providing
a full range of angular positions for the valve shaft 164 for opening and
closing the
valve. In this regard, assuming that the valve shaft 164 is in a fully closed
position
such that the valve shaft 164 allows no fluid flow, then rotating the integral
cut-off
screw 202 about 35 degrees transitions the valve shaft 164 from the fully
closed
position to the fully open position (i.e., the valve's flow rate is at a
maximum for a
given pressure). In such an example, there is no reason for the cut-off screw
202 to be
rotated outside of such a 35 degree range. However, the foregoing 35 degree
range is
provided herein as merely an example of the possible range of angular
movements for
the valve shaft 164, and other ranges are possible in other embodiments. For
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example, as described herein, the slots 224, 226 allow a range of angular
movement
of about seven degrees, which may be sufficient as the temperature of the
fluid
increases.
The motor 244 (FIG. 20) is an electric reversible motor with a portion of the
motor drive shaft 260 extending from the housing of the motor 244. The motor
244 is
reversible such that the rotation of the motor 244 in one direction will cause
the drive
shaft 260 to rotate in one direction, and rotation of the motor 244 in the
opposite
direction will cause the drive shaft 260 to rotate in the opposite direction.
Such motors
are widely commercially available and the construction and operation of such
motors
are well known; therefore, the details of the motor 244 are not described in
specific
detail herein. A suitable motor 244 for use in the door closer assembly 80 of
the
present invention is a 3-volt motor providing a gear ratio of 109:1 and a
rated torque
of 1.3 oz-in. The motor 244 operates under the direction and control of the
control
unit 110, which is electrically coupled to the motor via an electrical cable,
as will be
described below.
The design of the couplers 240, 242 can facilitate assembly and promote
interchangeability. In this regard, as described above, precise tolerances
between the
cut-off screw 202 and the motor shaft 260, as well as between couplers 240,
242, are
unnecessary. For example, the couplers 240, 242 may be used to reliably
interface
motors and door closers of different vendors. Moreover, to interface the motor
244
with the door closer 90, a user simply attaches the COS 164 coupler 240 to the
cut-off
screw 202 and positions the couplers 240, 242 such that the pin 255 on the
motor
coupler 242 is able to pass through the slot 268 in the COS 164 coupler 240 as
the
motor 244 is mounted on the door closer 90. As described above, there is no
need to
precisely align the couplers 240, 242 as long as the couplers 240, 242 are
appropriately positioned such that the pin 255 passes through the slot 268.
In this regard, slight misalignments of the couplers 240, 242 do not create
significant stresses between the couplers 240, 242. For example, assume that
the
couplers 240, 242 are slightly misaligned such that the centerline of the COS
164 does
not precisely coincide with the centerline of the motor shaft 260. That is,
the central
axis of rotation of the COS 164 coupler 240 is not precisely aligned with the
center of
rotation of the motor coupler 242. In such an example, the pin 255 moves
radially
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relative to the COS 164 coupler 240 as the couplers 240, 242 rotate. In other
words,
the pin 255 moves toward or away from the central axis of rotation of the COS
164
coupler 240 as the couplers 240, 242 rotate. If the pin 255 is not movable
along a
radius of the COS 164 coupler 240 when the couplers 240, 242 are misaligned,
then
the rotation of the couplers 240, 242 would induce stress in the couplers 240,
242 and
pin 255. However, since the pin 255 is radially movable relative to the COS
164
coupler 240 due to the dimensions of the slot 268, such stresses do not occur.
In addition,. as described above, the COS 164 coupler 240 is movable in the y-
direction (i.e., toward and away from the motor coupler 242) without creating
stresses
in the couplers 240, 242 or transferring significant forces from the COS 164
coupler
240 to the motor coupler 242. In this regard, the pin 255 is not fixedly
attached to the
COS 164 coupler 240, and the length of the slot 268 in the r-direction (i.e.,
along a
radius of the COS 164 coupler 240) is sufficiently large so that the COS 164
coupler
240 can slide along the pin 255 (or otherwise move relative to the pin 255)
without
transferring forces through the pin 255 to the motor coupler 242.
Referring to FIGs. 19 and 20, the PCB board 252 is positioned between the
motor coupler 242 and the COS 164 coupler 240. In one exemplary embodiment,
the
PCB board 252 is attached to the mounting bracket 246 via, for example, screws
253
(FIG. 17), but other techniques for mounting the PCB board 252 on the mounting
bracket 246 or other component are possible in other embodiments.
As shown by FIGs. 16 and 17, the fixed cap 248 is coupled to the mounting
bracket 246 with four screws. As shown by FIG. 24, the fixed cap 248 is
coupled to
the rotatable cap 250, which can be rotated relative to the fixed cap 248.
Referring to
FIG. 23, the rotatable cap 250 has a lip 278 that extends around a perimeter
of the cap
250. The cap 250 has a plurality of notches 280 along such perimeter, but such
notches 280 are unnecessary in other embodiments. The interior of the fixed
cap 248
defines a channel 282 (FIG. 24) into which the lip 278 fits and through which
the lip
278 slides. A tab 284 extends from the lip 278 and limits the movement of the
rotatable cap 250 relative to the fixed cap 248. In this regard, the fixed cap
248 has a
pair of stops (not shown). The cap 250 is rotatable within the tab 284 between
the
stops. As the cap 250 is rotated in one direction, the tab 284 eventually
contacts one
of the stops preventing further movement of the cap 250 in such direction. As
the cap
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250 is rotated in the opposite direction, the tab 284 eventually contacts the
other stop
preventing further movement of the cap 250 in such direction. In one exemplary
embodiment, the cap 250 is rotatable up to 180 degrees (i.e., half of full
revolution).
Limiting the movement of the cap 250 helps to prevent entanglement of a motor
cable
288 within or passing through the cap 250.
Referring to FIG. 26, an embodiment of the motor cable 288 is shown as a
flexible electrical cable and is electrically connected to the motor 244 and
the PCB
board 252. The rotatable cap 250 has a receptacle 286 for passing the motor
cable
288, such that the motor cable 288 extends outwardly through the cover. The
outer
end of the motor cable 288 terminates in a connector 290 that electrically
connects the
motor cable 288 to an electrical cable from the control unit, as will
described below.
Thus, one end of the motor cable 288 is connected to the cable 292 from the
control
unit 110, and the other end is connected to the PCB board 252 thereby
electrically
connecting the drive unit 100 to the control unit 110. It is possible to
position the
control unit 110 at various locations, such as either on top of or below the
door closer,
and to then rotate the cap 250 until the receptacle 286 is oriented in a
manner
conducive to receiving the motor cable 288. In addition, the cap 250 may be
rotated
such that the receptacle 286 is generally faced downward in order to help keep
rainwater from falling into the receptacle 286 and reaching electrical
components
housed by the covers 248, 250. Another embodiment of a cover 294 for the drive
unit
100 is shown in FIG. 27. In this embodiment, a slot 295 centered in the end of
the
cover 294 passes the motor cable 288, which protrude through the center of the
cap
294. The covers 248, 250, 294 may be composed of plastic, but other materials
for
the covers are possible in other embodiments.
The motor 244 is secured to the mounting bracket 246 using screws 274 (FIG.
17) received in threaded openings in the bracket 246. The motor 224 has
opposed
ears which are received in corresponding tabs on the bracket 246 for securing
the
motor 244 against rotation. A sealing ring 272 is received in a corresponding
recess
in the mounting bracket 246 and for engaging the door closer housing 114. The
mounting bracket 246 is then fastened to the door closer housing 114 using
threaded
fasteners received in axial threaded openings 270 in the corners of the end of
the
housing 114 (FIG. 3). Opposed axial tabs 271 are received in corresponding
openings
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at the other corners. The mounting bracket 246 is then fastened to the door
closer
housing 114 using threaded fasteners received in axial threaded openings 270
in the
corners of the end of the housing 114 (FIG. 3). The cut-off screw 202 passes
through
the opening of mounting bracket 246. The sealing ring 272 helps to keep any
water
from seeping between the drive unit 100 and the door closer 90 and reaching
the
various electrical components of the drive unit.
As shown by FIG. 25, two magnetic sensors 299a, 299b are mounted on an
inner surface 298 of the PCB board 252. The magnetic sensors 299a, 299b are
configured to detect the strength of the magnetic field generated by the
magnet 266 on
the motor coupler 242. Such a detection is indicative of the angular position
of the
valve shaft 164 of the door closer 90. As described herein, to change such
angular
position, the motor 244 rotates the motor shaft 260 causing the motor coupler
242 to
rotate so that the motor coupler 242 moves the pin 255 about the motor shaft
260.
Such rotation is translated to the COS 164 coupler 240 through the pin 255
When moving, the pin 255 presses against and moves the COS 164 coupler
240. In particular, the pin 255 rotates the COS 164 coupler 240 and,
therefore, the
cut-off screw 202 that is inserted into the hollow tab extension 256. The
rotation of
the cut-off screw 202 changes the angular position of the valve shaft 164.
Since
rotation of the motor coupler 242 ultimately changes the angular position of
the valve
shaft 164, the position of the magnet 266 relative to the sensors 299a, 299b
on the
PCB board 252, which is stationary, indicates the angular position of the
valve shaft
164.
The sensors 299a, 299b are configured to transmit a signal having a voltage
that is a function of the magnetic field strength sensed by both of the
sensors 299a,
299b. In one exemplary embodiment, the sensors 299a, 299b are ratiometric
sensors
such that a ratio (R) of the input voltage to the sensors to the output
voltage to the
sensors is indicative of the angular position of the valve shaft 164. In this
regard,
each discrete angular position of the valve shaft 164 is associated with a
specific
voltage ratio (R), which is equal to the input voltage of the sensor 299a,
299b divided
by the output voltage of the sensor 299a, 299b. For example, assume that to
open the
valve shaft 164 more so that flow rate increases, the motor coupler 242 is
rotated such
that the magnet 266 is moved closer to one of the sensors 299a thereby
increasing the
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magnetic field strength sensed by the sensor 299a. In such an example, R
increases
the more that the valve shaft 164 is opened. Further, R decreases when the
motor
coupler 242 is rotated such that the magnet 266 is moved away from the sensor
299a.
Thus, R decreases as the valve shaft 164 is closed in order to decrease flow
rate. It
also follows that the further away from the ratiometric sensor 299a that the
magnet
266 gets, the lower the reading R and therefore causing an eventual unknown
position
of the valve shaft 164. To prevent this as well as allowing for a longer
distance of
angular travel for the valve shaft 164, the other ratiometric sensor 299b can
simultaneously read positions as the first ratiometric sensor 299a readings of
R go out
of range. The other ratiometric sensor 299b then controls within the new range
using
the same methodology as described above. The only difference being that as the
readings from the first ratiometric sensor 299a get weaker, the other
ratiometric
sensor 299b will be in a better physical proximity to assume control.
In one exemplary embodiment, control logic stores data, referred to herein as
"valve position data," that maps various possible R values to their
corresponding
angular positions for the valve shaft 164. Thus, the control logic can
determine an R
value from a reading of the sensors 299a, 299b and use the stored data to map
the R
value to the angular position of the valve shaft 164 at the time of the
reading. In other
words, based on the reading from the sensors 299a, 299b and the mappings
stored in
the valve position data, the control logic can determine the angular position
of the
valve shaft 164.
Note that the use of a ratiometric sensor can be desirable in embodiments for
which power is supplied exclusively by a generator. In such an embodiment,
conserving power can be an important design consideration, and it may be
desirable to
allow the input voltage of the sensors 299a, 299b to fluctuate depending on
power
demands and availability. Using a voltage ratio to sense valve position allows
the
input voltage to fluctuate without impairing the integrity of the sensor
readings. In
other embodiments, other types of magnetic sensors may be used to sense the
magnetic field generated by the magnet 266.
In one exemplary embodiment, the electrical cables 288, 292 comprise at least
six wires. In this embodiment, the sensors 299a, 299b may be coupled to the
control
unit 110 via six wires of the cables 288, 292. Two wires carry an input
voltage for the
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sensors 299a, 299b circuitry. Two other wires carry an output voltage for the
sensors
299a, 299b, and the fifth and sixth wires carry an enable signal for each
sensor. In
this regard, each sensor 299a, 299b is configured to draw current from the
control
logic only when receiving an enable signal from the logic. Thus, if the
sensors 299a,
299b do not receive an enable signal, the sensors 299a, 299b do not usurp any
electrical power. Moreover, when the control logic desires to determine the
current
position of the valve shaft 164, the control logic first transmits an enable
signal to one
of the sensors 299a, 299b that should be activated based upon a temperature
profile or
table, waits a predetermined amount of time (e.g., a few microseconds) to
ensure that
the sensor 299a, 299b is enabled and providing a reliable reading, reads a
sample from
the one of the sensors 299a, 299b and then disables the sensor thereby
preventing the
sensor from drawing further current. Accordingly, for each reading, each
sensor
299a, 299b draws current only for a short amount of time thereby helping to
conserve
electrical power.
In one exemplary embodiment, readings from the sensors 299a, 299b are used
to assist in the control of the motor 244. In such an embodiment, the control
logic
instructs the motor 244 when and to what extent to rotate the motor shaft 260
(thereby
ultimately rotating the cut-off screw 202 by a corresponding amount) by
transmitting
pulse width modulation (PWM) signals to the motor 244 via electrical cable. In
this
regard, pulse width modulation is a known technique for controlling motors and
other
devices by modulating the duty cycle of control signals. Such techniques can
be used
to control the motor 244 such that the motor 244 drives the motor shaft 260 by
an
appropriate amount in order to precisely rotate the motor shaft 260 by a
desired angle.
In controlling the door closer 90, the control logic may determine that it is
desirable to set the angular position of the valve shaft 164 to a desired
setting. For
example, the control logic may determine that the angle of the door 82 has
reached a
point at which the force generated by the door closer 90 is to be changed by
adjusting
the angular position of the valve shaft 164. If the current angular position
of the valve
shaft 164 is unknown, the control logic initially determines such angular
position by
taking a reading of the sensors 299a, 299b in the drive unit 100. In this
regard, the
control logic enables the sensors 299a, 299b based on the temperature table,
waits a
predetermined amount of time to ensure that the sensors are enabled and is
providing
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a reliable value, and then determines the angular position of the valve shaft
164 based
on the sensor reading. In one exemplary embodiment in which the sensors 299a,
299b
are ratiometric, the control logic determines the ratio, R, of the input
voltage to the
sensor and the output voltage form the sensor and maps this ratio to a value
indicative
of the current angular position of the valve shaft 164 via the valve position
data.
Based on the current angular position of the valve shaft 164, the control
logic
determines to what extent the cut-off screw 202 is to be rotated in order to
transition
the valve shaft 164 to the desired angular position. For example, the control
logic can
subtract the desired angular position from the current angular position to
determine
the degree of angular rotation that is required to transition the valve shaft
164 to the
desired angular position. The control logic then transmits a PWM signal to the
motor
244 to cause the motor to rotate the motor shaft 266 by a sufficient amount in
order to
transition the valve shaft 164 to its desired angular position. In response,
the motor
244 rotates the shaft 266 thereby rotating the motor coupler 242. Since the
pin 255
passes through the COS 164 coupler 240, the COS 164 coupler 240 rotates in
unison
with the motor coupler 242 thereby rotating the cut-off screw 202.
Accordingly, the
motor 244 effectively drives the cut-off screw 202 such that the valve shaft
164 is
transitioned to its desired angular position. Once the valve shaft 164 is
transitioned to
its desired angular position, the control logic, if desired, can take another
reading of
the sensors 299a, 299b, according to the techniques described above, in order
to
ensure that the valve shaft 164 has been appropriately set to its desired
angular
position. If there has been any undershoot or overshoot of the angular
position of the
valve shaft 164, the control logic can transmit another PWM signal to the
motor 244
in order to activate the motor 244 to correct for the undershoot or overshoot.
FIGs. 28 and 29 depict an exemplary embodiment of the control unit 110. The
control unit 110 may also be referred to herein as a "controller". The
components of
the control unit 110 are housed by a two-piece cover 303a, 303b, which can be
mounted on the bottom or the top of the door closer 90.
As described above, the control unit 110 has a printed circuit board (PCB) 300
on which logic, referred to herein as the "control logic," resides. Such logic
may be
implemented in hardware, software, firmware, or any combination thereof. In an
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exemplary embodiment illustrated in FIG. 30, the control logic 580 is
implemented in
software and stored in memory 582 mounted on the PCB 300.
The exemplary embodiment of the PCB 300 depicted by Fig. 30 comprises at
least one processing element 585, such as a digital signal processor (DSP) or
a central
processing unit (CPU), that communicates to and drives the other elements of
the
PCB 300 via a local interface 588, which can include at least one bus.
Furthermore,
an electrical interface 589 can be used to exchange electrical signals, such
as power or
data signals, with other components in the door closer assembly 80 or external
to the
door closer assembly 80. In one exemplary embodiment, the electrical cable 292
of
the control unit 110 is coupled to the interface 589.
Note that Fig. 30 also shows a workstation 1000 optionally connected to the
electrical interface 589. This workstation may serve as an instruction
execution
platform to execute software 1002 stored on a storage medium 1004 that runs
during a
calibration mode to store calibration positional values in memory 582. The
calibration mode is discussed in detail later with respect to FIGs. 47 and 48.
In some
embodiments the calibration software may be in the workstation. In other
embodiments, it may be stored in memory 582. In still other embodiments, it
may
reside in part or in whole in both places. The software may be distributed as
part of a
computer program product including computer program code or instructions on a
medium or on media. The memory may be any of various types. In some
embodiments, an EEPROM can be used.
Any suitable computer usable or computer readable medium may be utilized.
The computer usable or computer readable medium may be, for example but not
limited to, an electronic, magnetic, optical, or semiconductor system,
apparatus, or
device. More specific examples (a non-exhaustive list) of the computer
readable
medium would include any tangible medium such as a portable computer diskette,
a
hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable
programmable read-only memory (EPROM, EEPROM or flash memory), a compact
disc read-only memory (CD-ROM), or other optical, semiconductor, or magnetic
storage device
The components of the PCB 300 receive electrical power from a generator,
which will be described in more detail below. It should be noted that there
are varied
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methods of harnessing door movement energy as well as translating the physical
movement into electrical energy, but due to the modular design of this
exemplary
embodiment of a door closer assembly 80, differing implementations can be used
when appropriate. One method explained in detail will be referred to as the
direct
drive method throughout this document.
Referring now to FIGs. 29 and 31, a large drive gear 302 is rotatably mounted
on a base plate 304 using an S-shaped bracket. The base plate 304 is supported
on
four internally threaded posts 305a and held in place with screws 305b
threaded into
the posts 305a. The drive gear 302 defines a star-shaped opening 306 for
receiving an
end of the pinion 112 of the door closer 90. The end of the pinion 112, which
is
square, fits in the opening 306 such that the large drive gear 302 is rotated
with the
pinion 112 during door 82 movement. The large drive gear 302 is the start of
all
direct drive method power generation. The drive gear 302 engages a chain 308.
Linear motion of the chain 308 in either the +/- x direction results in
corresponding
clockwise/counterclockwise rotation of a small drive sprocket 310
longitudinally
spaced from the drive gear 302 on the base plate 304. An idler tension gear
311 on
the base plate 304 is adjustable for holding the chain 308 at the appropriate
tension to
allow for all gear teeth to grip the chain 308 during door 82 motion.
The direct drive method harnesses the rotational motion from the pinion 112
of the door closer 90, which is coupled to the large drive gear 302. When the
pinion
112 rotates through door movement, such rotational motion is translated into
linear
motion down the chain 308 in the +/- x direction depending on clockwise or
counterclockwise rotation of the pinion 112. For example, if rotation of the
pinion
112 is in the clockwise direction, and the linear motion of the chain 308 is
in the -x
direction, it also follows that counter-clockwise rotation of the pinion 112
will
propagate the chain 308 in the +x direction. It should be noted that
rotational motion
of the pinion 112 in either the clockwise or counterclockwise direction is the
result of
the door 82 being opened or closed and will vary in eventual linear +/- x
motion
depending on orientation of mounting of the door closer assembly 80.
Referring to FIGs. 32 and 33, the drive sprocket 310 is fixed for rotation
with
a large compound box gear 312 on the opposite side of the base plate 304
through a
sprocket shaft 313. The box gear 312 has a larger diameter than the drive
sprocket
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310, thereby maintaining the rotational rate of the original door 82 motion.
The box
gear 312 also has a higher tooth density, which helps distribute the angular
rotational
torque, so varying materials can be used in the box gear design. This
arrangement
also helps prevent the box gear 312 from exerting a reverse torque and thereby
inhibiting the door from opening or closing freely.
Since the pinion 112 and the large box gear 312 will rotate in the same
clockwise or a counterclockwise direction depending on the direction the door
82 is
moving, a pair of clutch gears 314a, 314b are provided. The clutch gears 314a,
314b
ensure that, regardless of the direction of rotation of the box gear 312, all
downstream
gear rotation, including the final interpretation of a generator gear 330, is
the same
direction of rotation. Thus, electrical energy will be generated in the same
manner
regardless of the direction the door 82 is moving. The set of clutch gears 3
I4a, 314b
also ensures that the gears further downstream will not be subject to unwanted
gear
wear associated with bi-directional rotation. It should be noted that a
regulated
generator is an alternative design for this exemplary embodiment, which would
render
the pair of clutch gears unnecessary.
The gear train for achieving unidirectional rotation of the generator gear 330
is
shown in FIGs. 32-37. The clutch gears 314a, 314b are disposed on a shaft 315
extending between the base plate 304 and a support plate 320 secured to posts
extending from the base plate 304 such that the support plate 320 is spaced
from and
parallel to the base plate 304. Rotational motion from the box gear 312 is
directly
transferred to the inner clutch gear 314b by direct engagement with the larger
gear
316 of the box gear 312. The opposite rotational motion is simultaneously
transferred
from the box gear 312 through an intermediary gear 318. The intermediary gear
318
spins freely on a shaft 319 extending between the base plate 304 and the
support plate
320 by direct engagement with smaller gear 317 of the box gear 312. The
intermediary gear 318 directly engages the outer clutch gear 314a. The clutch
gears
314a, 314b are oriented such that the clutch gears 314a, 314b only grip the
shaft 319
for rotation in one direction. For example, when the box gear 312 rotates
clockwise,
the outer clutch gear 314a grips the shaft 315 through the intermediary gear
318 and
turns the shaft 315 in the clockwise direction. The inner clutch gear 314a
spins freely
in the counterclockwise direction. It also follows that when the box gear 312
rotates
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in the counterclockwise direction, the inner clutch gear 314b directly grips
the shaft
315 and rotates the shaft 315 in the clockwise direction while the outer
clutch gear
314a spins freely in the counterclockwise direction through the intermediary
gear 318.
In this manner, the shaft 315 only receives one direction of rotation, which
is
transferred to a fixed drive gear 322 non-rotatably disposed on the shaft 315
on the
other side of the base plate 304. Thus, a single direction of rotation is
established for
all gears between the generator gear 330 and the clutch gears 314a, 314b. It
follows
that, since the door 82 opening or closing motion can be translated into
unidirectional
rotation on the fixed drive gear 322, all subsequent gears will only see one
direction
of rotation regardless of whether the door 82 is opening or closing.
The fixed drive gear 322 transfers rotational motion through a series of
compound gears 324, 326, 328, 330 with the explicit intent to increase overall
rotational velocity for any given motion of the pinion 112, which is directly
derived
from door 82 movement. The fixed drive gear 322 engages the smaller inner gear
of
the compound gear 324 rotatably mounted on an adjacent shaft 332. The larger
gear
of the compound gear 324 engages the smaller gear of the compound gear 326
rotatably mounted on the clutch gear shaft 315. The larger gear of the
compound gear
326 engages the smaller gear of the third, large compound gear 328 which is
also on
the adjacent shaft 332. This final higher velocity rotation of the large
compound gear
328 is transferred to the generator gear 330 affixed to a generator 334.
For the embodiment as depicted, the rotational energy derived from door
opening or closing and redirected through the subsequent gear train described
above is
used by the generator 334 to generate electrical power. The large drive gear
302
advances the chain 308 by door movement in the opening or closing direction,
and the
generator 334 generates power when the door is moving. The generator supplies
power through connected wires, which may be part of a multi-conductor cable,
such
as cable 292. When the door 82 is no longer moving, such as after the door
fully
closes, various electrical components, such as components on the PCB 300, are
shut-
off. Thus, the electrical power requirements of the door closer assembly 80
can be
derived solely from movement of the door, if desired. Once a user begins
opening the
door, the movement of the door 82 directly drives the large drive gear 302 and
subsequently the gear train to the generator 334 and electrical power is,
therefore,
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generated. When the generator 334 begins providing electrical power, the
electrical
components are powered, and the door closer assembly 80 is controlled in a
desired
manner until the door closes or otherwise stops moving at which time various
electrical components are again shut-off.
It should be emphasized that techniques described above for generating
electrical power are exemplary. Other techniques for providing electrical
power are
possible in other embodiments, and it is unnecessary for electrical components
to be
shut-off in other embodiments. In addition, other devices besides a generator
can be
used to provide power for the controller 110. For example, it is possible for
the
control unit 110 to have a battery (not shown) in addition, or in lieu of, the
generator
334 in order to provide power to the electrical components of the door closer
assembly 80. In such a case, the device to provide power consists of a battery
holder
with connections for the control circuitry. However, a battery, over time,
must be
replaced. The device to provide power might also be a connector or wires to
interface
with external power. In one exemplary embodiment, the control unit 110 is
designed
such that all of the electrical power used by the control unit 110 is
generated by the
generator 334 so that use of a battery is unnecessary. In other embodiments,
electrical
power can be received from other types of power sources.
As described above, the control logic 580 may function to adjust the angular
position of the valve shaft 164 based on the door angle. There are various
techniques
that may be used to sense door angle. In one exemplary embodiment, the control
logic 580 is configured to sense the door angle based on a magnetic position
sensor,
similar to the techniques described above for sensing the angular position of
the valve
shaft 164 via the magnetic sensors 299a, 299b in the drive unit 100.
Referring to FIGs. 38-40, the control unit 110 comprises an arcuate arm gear
336 that is coupled to the pinion 112 through the drive gear 302 and arm
encoder
gears 331a, 331b. The arm encoder gears 331a, 331b are fixed for joint
rotation on a
post 338 extending from the base plate 304 at a position longitudinally spaced
from
the drive gear 302. The smaller upper encoder gear 321b is engaged with the
arm
gear 336. As best seen in FIG. 40, the drive gear 302 has a smaller inner gear
that
engages the larger arm encoder gear 331a. When the large drive gear 302
rotates with
the pinion 112, the lower arm encoder gear 331a also rotates by engagement
with a
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smaller inner gear 362 on the drive gear 302. Since the upper arm encoder gear
331b
rotates with the lower arm encoder gear 331a, interaction of the upper arm
encoder
gear 33 lb and the arm gear 336 rotates the arm gear 336. Thus, any rotation
of the
pinion 112 caused by movement of the door 82 causes a corresponding rotation
of the
arm gear 336. In one embodiment, the pinion 112 rotates at a ratio of six-to-
one
relative to the arm gear 336. That is, for six degrees of rotation of the
pinion 112, the
arm gear 336 rotates one degree. However, other ratios are possible in other
embodiments.
At least one magnet 340 is mounted on the arm gear 336. The PCB 300 is
mounted over the arm gear 336 on four threaded posts with screws. At least one
magnetic sensor 342 is mounted on the PCB 300. The magnetic sensor 342 is
stationary, and the magnet 340 moves with the arm gear 336. Thus, any movement
by
the door 82 causes a corresponding movement by the magnet 340 relative to the
sensor 342. The control logic 580 is configured to determine a value
indicative of the
magnetic field strength sensed by the sensor 342 and to then map such value to
the
angular position of the door 82. Further, as described above, the control
logic 580 is
configured to use the angular position of the door 82 to control the angular
position of
the valve shaft 164, thereby controlling the force generated by the door
closer 90.
For illustrative purposes, assume that it is desirable for the door closer 90
to
control the hydraulic force generated by the closer during opening based on
two door
angles, referred to hereafter as "threshold angles," of fifty degrees and
seventy
degrees. In this regard, assume that the door closer is to generate a first
hydraulic
force resistive of the door motion during opening for door angles less than
fifty
degrees. Between fifty and seventy degrees, the door closer is to provide a
greater
hydraulic force resistive of the door motion. For door angles greater than
seventy
degrees, the door closer is to provide a yet greater hydraulic force resistive
of the door
motion. This high-force region of motion is often termed the "back check"
region,
since the greater force is intended to prevent the back of the door from
hitting a wall
or stop. Further assume that during closing, the closer is to generate another
hydraulic
force for door angles greater than fifteen degrees and a smaller hydraulic
force for
door angles equal to or less than fifteen degrees. This latter region, where
the door is
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close to the jamb, is often referred to as the "latch region" of motion. These
angles
are a design choice and can vary.
As shown by FIG. 30, the control logic 580 stores threshold data 590
indicating the desired opening and closing characteristics for the door 82. In
this
regard, the data 590 indicates the threshold angles and the desired angular
position of
the valve for each threshold range. In particular, the data 590 indicates that
the
angular position of the valve is to be at one position, referred to hereafter
as the "high-
flow position," when the door angle is fifty degrees or less during opening,
but the
door is not in the latch region. The data 590 also indicates that the angular
position of
the valve to be at another position, referred to hereafter as the "medium-flow
position," when the door angle is greater than fifty degrees but less than or
equal to
seventy degrees during opening. The data 590 further indicates that the
angular
position of the valve is to be at yet another position, referred to hereafter
as the "low-
flow position," when the door angle is greater than seventy degrees during
opening,
and thus the door is in the back-check region. Note that the medium-flow
position
allows a lower flow rate than that allowed by the high-flow position, and the
low-flow
position allows a lower flow rate than that allowed by the medium-flow
position, and
also that there may be many variations of angle used as trigger points for
entering into
a particular flow rate region as well as numerous degrees of each flow rate
described
above. Thus, the hydraulic forces generated by the closer resisting door
movement
should be at the highest above a door angle of 70 degrees and at the lowest
below a
door angle of 50 degrees. In addition, assume that the data 590 also indicates
that,
when the door is closing, the angular position of the valve is to be at a
position for
angles less than or equal to 15 degrees to allow for very slow closing in the
latch
region.
In some embodiments of the closer assembly, velocity measurements of door
movement can add more intelligence to COS 164 movement decisions. Deciding if
a
threshold has been met is only one scenario of trying to mitigate an
unnecessary
reposition of the COS 164. It also follows that if door movement is slow
enough
during opening mode that there will not be a need to move the COS 164 to the
next
mode of COS, valve operation stored in the threshold data 590. For instance,
if when
opening the door 82 under normal decision processing, the threshold data 590
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determines that the door movement requires the COS 164 be positioned at a low
flow
rate to prevent the door from opening further than desired, it then will have
to perform
another movement to position the COS 164 in the appropriate position for a
close
mode when the threshold data 590 has determined it is necessary. So, in this
embodiment, the COS 164 had to make two movements and therefore use energy for
moving the COS 164 both times. However, if after determining the door 82 is
closing
the determination was made whether there was a predetermined high velocity
violation, the decision for determining if the COS 164 should be moved to the
next
position would only happen if velocity is too high. This will help conserve
energy
during slow door movement, which does not require a low-flow rate to protect
the
door from opening too fast and therefore allow the closer to bypass one
movement of
the COS 164 as normal operation would indicate. A process that can be used to
measure the velocity of the door is to determine the door angle difference
over time
using a timer in the control logic 580. Furthermore, it also follows that this
same
velocity measurement can be used to make other decisions that the control
logic 580
will discern. For example, if the velocity is extremely high, a decision could
be made
to move COS 164 to a low flow rate position sooner than threshold data 590
normally
requires. This would be useful in a scenario where a door 82 is being kicked
and
thereby prevent damage to people or the surroundings.
As described above, electrical power can be harnessed from the energy created
by door movement. In one exemplary embodiment, all of the electrical power for
powering the electrical components of the door closer 90, including electro-
mechanical components, such as the motor 244, is derived from door movement.
Accordingly, the door closer assembly 80 may not be provided with power from
an
external power source and does not require batteries. Since power is limited
and only
available when the door 82 is moving and a short time thereafter, various
techniques
are employed in an effort to conserve power to help ensure that there is
enough power
to control valve position in a desired manner.
In one embodiment, the sensors 299a, 299b in the drive unit 100 and the
sensor 342 in the control unit 110 are enabled only for enough time to ensure
that an
accurate reading is taken. In this regard, the control logic 580 enables the
sensors
299a, 299b, waits a short amount of time (e.g., a few microseconds), takes a
reading,
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and then disables the sensors 299a, 299b. Indeed, in one embodiment, the
control
logic 580 enables the one of the sensors 299a, 299b in the drive unit 100 in
response
to a determination that a reading of the sensor 299a, 299b should be taken,
and the
control logic 580 thereafter disables the sensors 299a, 299b in response to
the
occurrence of the reading. Thus, for each reading, the sensor 299a, 299b draws
power
for only a short time period, such as about 10 microseconds. Similarly, the
control
logic 580 enables the sensor 342, waits a short amount of time (e.g., a few
microseconds), takes a reading, and then disables the sensor 342. Thus, for
each
reading, the sensor 342 draws power for only a short time period, such as
about 10
microseconds. Note that, as described above for the drive unit sensors 299a,
299b, the
sensor 342 on the POCB 300 may be enabled in response to a determination that
a
reading of the sensor 342 should be taken and may be disabled in response to a
determination that such reading has occurred.
To further help conserve power, the control logic 580 tracks the amount of
power that is available and takes various actions based on the amount of
available
power, as will be described in more detail below. In one embodiment, FIG. 41
depicts an exemplary circuit for providing power to various electrical
components of
the door closer assembly 80. In this regard, a power management circuit 525 is
coupled to the generator 334 via a diode 527. As described herein, when the
large
drive gear 302 in the control unit 110 is rotated by door movement, and the
chain 308
transfers the motion through the gear train, the generator 334 generates an
electrical
pulse. As long as the door continues moving, the generator 334 repetitively
generates
electrical pulses.
Each electrical pulse from the generator 334 charges the power management
circuit 525. The power management circuit 525 is comprised of a charge pump
525a,
SuperCapTM battery ("SuperCap") 525b, and an electrolytic capacitor 525c,
which are
electrically combined to maximize instant voltage output for low power
situations and
to maximize energy storage when power is being generated. In general, as power
is
generated by the generator 334, a circuit detects if the voltage being
generated is
greater than zero volts but less than 5 volts, and if so will turn on the
charge pump
525a to double the voltage. This type of circuit can help minimize the errors
that a
slow moving door can cause when not enough power is available to move the COS
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164 to the appropriate position. For example, in this exemplary embodiment, a
slow
moving door may provide one to two volts on the onset of the slow movement and
therefore not generate enough energy for control circuitry 540 to determine if
a valve
movement needs to take place, but with the charge pump the control circuitry
540
would wake immediately and determine next course of action without delay and
therefore be able to move the COS 164 when appropriate.
However, once the voltage level increases past five volts from the generator
334, the efficiencies of the charge pump 525a start to reduce and may damage
the rest
of the circuit, so the circuit then switches the outputted voltage away from
the charge
pump 525a and directly charges the electrolytic capacitor 525c until such time
the
voltage being generated then rises above 6 volts, which then means the energy
being
produced is more than required for immediate use, so it can be stored. Upon
determining extra voltage is available the circuit then allows the outputted
energy to
charge the carbon SuperCap 525b and the electrolytic capacitor 525c
simultaneously
so that all energy being generated is available for valve operation or being
stored for
later use. Since the electrolytic capacitor 525b is of much smaller
capacitance, its
charging and discharging properties are relatively fast and respond to COS 164
movement needs instantaneously. The carbon SuperCap 525b has a much higher
capacitance and is used to recharge the electrolytic capacitor when no power
is being
generated but energy is still needed for valve operation.
Accordingly, if the door is moving fast enough, electrical power is
continually
delivered to control circuitry 540 during such movement. As shown by FIG. 41,
a
voltage regulator 545 is coupled to the capacitor 525c and regulates the
output from
the power management circuit 525, so that this voltage is constant provided
that there
is sufficient power available to maintain the constant voltage. For example,
in one
embodiment, the regulator 545 regulates the voltage across the power
management
circuit 525 to three volts. Thus, as long as the power management circuit 525
is
sufficiently charged, the regulator 545 keeps the voltage across capacitor
525c equal
to three volts. However, if the door stops moving thereby stopping the
generation of
electrical pulses by the generator 334, then the voltage across the power
management
circuit 525 eventually falls below three volts as the electrolytic capacitor
525c and
carbon SuperCap 525b discharges.
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Also as shown by FIG. 41, the control circuitry 540 in one exemplary
embodiment comprises a microprocessor 555. Further, in such embodiment, at
least a
portion of the control logic 580 is implemented in software and run on the
microprocessor 555 after being loaded from memory. The microprocessor 555 also
comprises a timer 563 that is configured to generate an interrupt at certain
times, as
will be described in more detail hereafter.
The parameters on which decisions are made to adjust valve position change
relatively slowly compared to the speed of a typical microprocessor. In this
regard, a
typical microprocessor is capable of detecting parameters that have a rate of
change
on the order of a few microseconds, and a much longer time period is likely to
occur
between changes to the state of the valve position. To help conserve power,
the
control logic 580 is configured to transition the microprocessor 555 to a
sleep state
after checking the sensors 299a, 299b, 342 and adjusting valve position based
on such
readings, if appropriate.
Before transitioning to the sleep state, the control logic 580 first sets the
timer
563 such that the timer 563 expires a specified amount of time (e.g., 100
milliseconds) after the transition to the sleep state. When the timer 563
expires, the
timer 563 generates an interrupt, which causes the microprocessor 555 to
awaken
from its sleep state. Upon awakening, the control logic 580 checks the sensors
299a,
299b, 342 and adjusts the valve position based on such readings, if
appropriate. Thus,
the microprocessor 555 repetitively enters and exits a sleep state thereby
saving
electrical power while the microprocessor 555 is in a sleep state. Note that
other
components of the control circuitry 540 may similarly transition into and out
of a
sleep state, if desired.
In one exemplary embodiment, the control logic 580 monitors the voltage
across the power management circuit 525 to determine when to perform an
orderly
shut-down of the control circuitry 540 and, in particular, the microprocessor
555. In
this regard, the control logic 580 is configured to measure the voltage across
the
power management circuit 525 and to compare the measured voltage to a
predefined
threshold, referred to hereafter as the "shut-down threshold." In one
embodiment, the
shut-down threshold is established such that it is lower than the regulated
voltage but
within the acceptable operating voltage for the microprocessor. In this
regard, many
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microprocessors have a specified operating range for supply voltage. If the
microprocessor is operated outside of this range, then errors are likely.
Thus, the
shut-down threshold is established such that it is equal to or slightly higher
than the
lowest acceptable operating voltage of the microprocessor 555, according to
the
microprocessor's specifications as indicated by its manufacturer. It is
possible for the
shut-down threshold to be set lower than such minimum voltage, but doing so
may
increase the risk of error.
If the measured voltage falls below the shut-down threshold, then the power
management circuit 525 has discharged to the extent that continued operation
in the
absence of another electrical pulse from the generator 334 is undesirable. In
such
case, the control logic 580 initiates an orderly shut-down of the control
circuitry 540
and, in particular, the microprocessor 555 such that continued operation of
the
microprocessor 555 at voltages outside of the desired operating range of the
microprocessor 555 is prevented. Once the shut-down of the microprocessor 555
is
complete, the microprocessor 555 no longer draws electrical power.
In addition, the control logic 580 may be configured to take other actions
based on the measured voltage of the power management circuit 525. For
example, in
one embodiment, the control logic 580 is configured to delay or prevent an
adjustment
of valve position based on the measured voltage. In this regard, as the
capacitor 525c
discharges, the measured voltage (which is indicative of the amount of
available
power remaining) may fall to a level that is above the shut-down threshold but
nevertheless at a level for which the shut-down threshold will likely be
passed if an
adjustment of valve position is allowed. In this regard, performing an
adjustment of
the valve position consumes a relatively large amount of electrical power
compared to
other operations, such as reading sensors 299a, 299b, 342. As described above,
to
change valve position, the motor 244 is actuated such that the COS 164 is
driven to an
appropriate position in order to effectuate a desired valve position change.
If the
voltage of the power management circuit 525 is close to the shut-down
threshold
before a valve position adjustment, then the power usurped by the motor 244 in
effectuating the valve position adjustment may cause the voltage of the power
management circuit 525 to fall significantly below the shut-down threshold.
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In an effort to prevent the capacitor voltage from falling significantly below
the shut-down threshold, the control logic 580 compares the measured voltage
of the
power management circuit 525 to a threshold, referred to hereafter as the
"delay
threshold," before initiating a valve position change. The delay threshold is
lower
than the regulated voltage but higher than the shut-down voltage. Indeed, the
delay
threshold is preferably selected such that, if it is exceeded prior to a valve
position
adjustment, then the power usurped to perform such adjustment will not likely
cause
the capacitor voltage to fall significantly below the shut-down threshold.
If the measured voltage is below the delay threshold but higher than the shut-
down threshold, then the control logic 580 waits before initiating the valve
position
adjustment and continues monitoring the capacitor's voltage. If an electrical
pulse is
generated by the generator 334 before the shut-down threshold is reached, then
the
pulse should charge the power management circuit 525 and, therefore, raise the
voltage of the power management circuit 525. If the measured voltage increases
above the delay threshold, then the control logic 580 initiates the valve
position
adjustment. However, if the measured voltage eventually falls below the shut-
down
threshold, then the control logic 580 initiates an orderly shut-down of the
circuitry
540 and, in particular, the microprocessor 555 without performing the valve
position
adjustment. However, it may be more desirable to ensure that the COS 164 is
positioned in a known safe state as the last operation before allowing any
valve
movements that may cause an interruption to the control circuit. For example,
if a
door is in a closing function and the control circuitry 540 determines that
there is only
enough energy for one more COS 164 movement, so instead of moving the COS 164
into the final COS position before reaching full close, the last move may be
to put the
COS in the ready to open position to ensure correct functioning for the next
user of
the door.
As described herein, the control unit 110 can be mounted in many orientations
with respect to the door closer 90 with a variety of arm mounting options. For
example, the control unit 110 can be mounted on top of or on bottom of the
door
closer 90. Further, the components of the control unit 110 are designed to be
operable
for multiple orientations of the control unit 110 with respect to the pinion
112. In one
embodiment, the control unit 110 is secured to the door closer via screws,
which pass
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through the control unit 110 and into the door closer 90. Whether the control
unit 110
is mounted on the top or bottom of the door closer 90, the same side of the
control
unit 110 abuts the door closer 90 such that the large opening defined in the
cover
receives the end of the pinion 112. That is, the control unit 110 is rotated
180 degrees
when changing the mounting from the top of the door closer 90 to the bottom of
the
door closer 90 or vice versa. In other embodiments, other techniques and
orientations
for mounting the control unit 110 are possible.
When the control unit 110 is mounted on one side (e.g., top) of the door
closer
90, the pinion 112 may rotate in one direction (e.g., clockwise) relative to
the large
drive gear 302 when the door is opening, but when the control unit 110 is
mounted on
the opposite side (e.g., bottom) of the door closer 90, the arm shaft may
rotate in the
opposite direction (e.g., counter-clockwise) relative to the large drive gear
302. The
control unit 110 is operable regardless of whether the pinion 112 rotates
clockwise or
counter-clockwise when the door is opening.
Once an installer has mounted the door closer assembly 80 for whatever
orientation desired, the control logic 580 must be taught the specifics of the
relative
final angular displacement that the control unit 110 will see during
operation. In
particular, the control unit 110 must know if the door closer assembly 80 is
mounted
as a parallel mount, top jamb mount, or normal mount, whether the swing of the
door
is left-handed or right-handed, and then the corresponding closed position of
the door
82 as well as the 90 degree open position. This is because the range of
angular
displacement of the arm encoder gear 336 will differ for each installation. In
addition,
installers may choose varying physical locations even within these mounting
options.
The end result of such a variety of possible installation orientations is that
the overall
angular displacement of the pinion 112 during door operation will vary such
that any
set parameters for where threshold data 590 has predetermined a change in COS
164
positioning may not be correct for the expectations of the user.
In one embodiment, a teach button assembly provides a means for an installer
to inform the control logic 580 what configuration has been chosen to assist
in setting
the appropriate threshold data 590 for proper operation. Referring to FIGs. 38
and 42-
43B, the teach button assembly depicted includes a teach button 350 and a
magnet
352. In some embodiments, the door closer assembly 80 can be initially pre-set
as
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determined by the manufacturer as the most common mode of operation based upon
market knowledge. First the installer is instructed to install the door closer
assembly
80 as described in installation instructions onto a door. After installation
is complete,
the installer then energizes the electronics of the control unit 110 by
opening the door
and closing the door up to three times and then allowing the door to rest at
close.
Then the installer is instructed to push the teach button 350 a certain number
of times
which indicates what style of installation the closer is in (i.e., regular,
top jamb
mount, or parallel mount). In another embodiment. an alternate method of
indicating
the style would be to use switch settings located on the control unit 110 and
accessible
to the installer.
Once the style is selected, the installer then opens the door 82 to 90
degrees,
where the arm encoder gear 336, magnetic sensor 342 on the PCB 300, and
control
logic 580 store the values for calibration calculations. The installer is then
instructed
to release the door 82 such that when it comes to rest at the closed position
the arm
encoder gear 336, the magnetic sensor which may be a Hall effect sensor 342,
and
control logic 580 stores the values for calibration calculations. Once the
door 82
returns to the closed position, the door closer assembly 80 has been taught
for its
specific installation parameters. Threshold data 590 is updated and will stay
constant
until the teach button 350 is invoked again, as described above. This
operation can be
redone as many times as deemed necessary for either a mistake during the
installation
process, if the door closer assembly is removed and put on another door, or if
style is
changed for the existing door.
The teach button 350 is accessible in an opening in the cover of the control
unit 110. When the teach button 350 is pushed, another magnetic sensor 354,
such as
a Hall effect sensor, on the PCB 300 will recognize that the magnetic field
strength
from the teach button magnet 352 has deviated and that the teach operation has
been
invoked. Referring to FIG. 43B, at the point that the teach button 350 is
fully
depressed, the upper arm encoder gear 331b engages and compresses a spring 344
between the arm encoder gears 331a, 331b and disengages the arm encoder gear
331b
from the arm gear 336. This allows the arm gear 336 to spring back to a home
position due to a spring 337 affixed to a tab 366, such that the one or more
magnets
340 on the arm gear 336 aligns to a zero position relative to the one or more
sensors
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342 on the PCB 300. When the teach button is released, the spring 344 acts to
push
the upper encoder gear 331b back into engagement with the arm gear 336, thus
fixing
all gears to this new known zero state. It should be understood that a known
zero
state implies that the door is in the closed position, the arm has been
preloaded, and
power has been generated for the door 82 to recognize the teach operation has
been
initiated. During the next step of opening the door 82 to 90 degrees, the arm
encoder
gear 336 rotates as described above. Specifically, the pinion 112, due to door
82
movement, rotates the large drive gear 302. The lower gear of the drive gear
302
engages and rotates the lower arm encoder gear 331a. Rotation of the lower arm
encoder gear 331a rotates the upper arm encoder gear 331b. The upper arm
encoder
gear 331b engages and rotates the arm gear 336, which changes the relative
position
of the magnet 340 and the sensor 342. The control logic 580 monitors this
activity
and calibrates the ratiometric readings for both the zero position and the 90
degree
position of the door 82, along with physical characteristics of known angular
distances for a full sweep of 90 degrees, such that now COS 164 threshold data
590
can be augmented for the specific installation.
In additional embodiments, the teach mode of a door closer may follow the
process illustrated in FIG. 44. FIG. 44 is a flowchart that is presented as
FIG. 44A,
FIG. 44B, and FIG. 44C for clarity. Like many flowcharts, FIG. 44 illustrates
the
method or process as a series of process or sub-process blocks. The teach mode
process 2100 begins in this embodiment at block 2102. At block 2104, user
interface
switches are read by the controller to determine the installation
configuration. At
block 2106 of FIG. 44A, the user opens and closes the door to power the
controller.
At block 2108, the control circuitry detects that the user has pressed the
teach button
of the door closer with the door at jamb position. At block 2110, the user
opens the
door at least past the 45 degree position, in most cases, following
instructions
supplied with the door closer. The arm gear 336 is monitored at block 2112 and
values are stored in memory as variable ADX. Alternately, at some time
interval, for
example, 100ms, the arm gear 336 is monitored and a second value is stored in
memory as variable ADN at block 2114. Processing then proceeds as indicated by
off-page connector 2116, to incoming off page connector 2118 in FIG. 44B.
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Continuing with FIG. 44B, a determination is made at block 2120 as to
whether ADN is greater than ADX while the door is opening. If so, it is
determined
that the door must be mounted for left handed opening, and a value indicating
this is
stored at block 2122. The two variables are set to be equal at block 2124 and
at block
2126, the second variable is again updated after a time delay. The variables
are
compared again at block 2128. If the value of the second variable has
increased at
decision block 2128, it is determined that the door is still opening at block
2130 and
this part of process 2100 repeats. Otherwise, it can be assumed that the door
is now
closing at block 2132.
Still referring to FIG. 44B, if ADN is not greater than ADX at block 2120, the
door must be mounted for right handed operation and a value indicated this
type of
swing information is stored at block 2134. The two variables are set to be
equal at
block 2136 and at block 2138, the second variable is again updated after a
time delay.
The variables are compared again at block 2140. If the value of the second
variable
has decreased at decision block 2140, the door is still opening at block 2142
and this
part of the process 2100 repeats. Otherwise, it can be assumed that the door
is now
closing at block 2132. Note that the selection and naming of variables, and
which one
increases based on movement of the door, is arbitrary and will vary depending
on the
particular hardware and software design of the control unit. Once this portion
of the
process is completed and the door begins to close, processing moves to FIG.
44C via
off page connector 2150.
Turning to FIG. 44C, processing picks up with incoming off page connector
2152, where the value of the variable ADN is again updated and stored at block
2154.
At decision block 2156 a determination is made as to whether the two variables
are
equal. If not, it can be assumed that the door is still moving at block 2158,
in which
case the variables are set to be equal again at block 2160 and the variable
ADN is
updated again. Otherwise, it can be assumed that the door has reached the jamb
position at block 2162, and the value is stored as the jamb value and checked
against a
stored calibration curve. If necessary, values can be skewed at block 2164, or
an error
can be reported if the value makes no sense. Process 2100 ends at block 2168,
normally with the controller exiting the teach mode. The processes involved in
obtaining calibration data are described below.
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Due to mechanical tolerance stack up expectations, after final assembly of the
door closer 90 and the drive unit 100, a final calibration capability can also
be
designed into the control logic 580, such that when motor calibration is
invoked via a
predefined command, the door closer assembly 80 will determine the ratiometric
value seen by hall effect sensors 299a, 299b that designate a COS 164 position
for a
fully opened valve and a COS position for a fully closed valve.
For example, in this exemplary embodiment the calibration method would
start with a fully assembled door closer assembly either on a test bench or
installed on
a door, interconnected with an interface controller board (factory board) such
that
commands can be sent to the control unit 110 and the control unit 110 can be
monitored and controlled by an external software application. This application
can be
designed to invoke the motor calibration via a predefined command through any
standard serial communication interface. At such a time, the control logic 580
would
prompt the user to rotate the closer arm ninety degrees and release, relying
on the
spring tension of the door closer 90 to try and force the arm 94 of the
linkage
assembly 92 to the door closed position. It should be noted that the choice of
90
degrees as the amount of movement required for calibration is an example, and
that
other implementations can use other values as necessary.
The control logic 580 will then send PWM pulses to the motor 244, such that
the motor coupler 242 turns the COS 164 coupler 240 and then an eventual
rotation of
the COS 164 with the intent of finding the fully closed position of the valve.
Control
logic 580 simultaneously monitors the output data of the arm gear 336 through
the
hall effect sensor 342 readings of the magnet 340. If the control logic 580
senses
movement of the arm encoder gear 336, the control logic 580 will continue to
move
the COS 164 to a more closed position until it is determined that arm encoder
gear
336 has stopped moving. At this point, the reading from the magnetic or Hall
effect
sensor 299a will be read and stored in the threshold table as the known, valve-
closed
position for the COS 164. It should be noted that the calibration routine may
be
designed to move the COS 164 multiple times between the open and closed
positions
and monitor the effects thereof for further determination of a truly closed
position.
The control logic 580 can send the COS 164 towards the full open position and
monitor both hall effect sensors 299a, 299b in the drive unit 100 for their
minimum
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sensor reading feedback change. The ratiometric readings reduce as the magnet
266
on the motor coupler 242 gets further away from the Hall effect sensors 299a,
299b,
and there will be a point that the values will stop changing and therefore
signify a
ratiometric measurement that will be stored for that sensor for this
calibration on a
particular closer assembly. In this manner, mechanical variations can be taken
into
account for the minimum and maximum ranges of the sensors 299a, 299b in the
drive
unit 100 such that final values can be stored in the threshold data 590.
Calibration as
described above includes human intervention to move the closer arm. However,
calibration can be automated by providing mechanized, computer-controlled
apparatus to move the door closer during calibration.
FIG. 45 illustrates how a calibration curve works. Arm positional values for
such a curve can be stored in the memory of a controller for use in operations
such as
the teach mode. In the case of FIG. 45, calibration of the arm gear 336 is
shown. The
arm gear 336 includes a North magnet 382 and a South magnet 383. These magnets
interact with magnetic or Hall effect sensors on the PCB 300. A clockwise
calibration
curve 2210 and a counter clockwise calibration curve 2212 are shown in the
graph,
which the virtual jamb position 2220 residing at or near the middle of both
curves.
For a right hand opening door, the right side of the graph is used, as is the
part of the
arm gear 336 shown on the right. For a left hand opening door, the left side
of the
graph is used, as is the part of the arm gear 336 shown on the left. The PCB
300 and
the arm gear 336 are shown aligned with the graph for clarity.
It has been determined that when using an electro-mechanical device such as
described herein to measure an angular position of a door, that it is
necessary to
profile both the opening motion and closing motion independently for the door,
such
that physical door angles can be converted into electrical AID measurements
and
stored away in memory on main board in the form of data for curves like those
shown
in FIG. 45. The reason for this dual profile is to ensure that any mechanical
gear
tolerance motion deviation when direction of door mount is changed is
accounted for.
Thus, an arm gear 336 is put through a calibration process as described
herein. The
calibration curve information stored in memory can then be used in the teach
mode
previously described so that any tolerance deviations for all mounting options
can be
accounted for during normal operation.
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FIG. 46 illustrates a motor encoder calibration curve made up of valve
positional values in a manner similar to the way the arm gear 336 calibration
curve
was illustrated above. The graph shows the motor angle displacement on
horizontal
or x-axis 2302 and the digital value on vertical or y-axis 2304. The graph is
superimposed over a schematic view of the motor coupler 242 to illustrate the
relationship of the curve to physical position. The digital value of the motor
244 may
also be referred to as the number of "clicks" in possible movement of the
motor. In
this embodiment, the number of clicks can be from zero to 255. A maximum A/D
value 2306 and a delayed action A/D value 2308 are shown on closed portion
2310 of
the calibration curve. A minimum A/D value 2312 is shown on the open portion
2314
of the calibration curve. It can also be observed that in this embodiment, the
curve
crosses the y-axis at 127.5 clicks, and the displacement angle range for the
motor is
from zero to 45 degrees. Referring to the schematic diagram of the motor
coupler 242
over which the graph is superimposed, mechanical stop 2220 is effective in the
close
direction and mechanical stop 2222 is effective in the open direction. The
magnet
266 in the drive unit, previously discussed, is also visible, along with
addition magnet,
2328.
The motor assembly 244 has its own electro-mechanical tolerance stack up
deviation from unit to unit when installed with a particular valve assembly
120 and
thus requires a calibration for proper operation. Overall, the calibration
procedure is
designed to find a minimum A/D value. The A/D reading is a value with respect
to
the relative position of the magnets on the arm gear 336 to the hall effect
sensor on
the PCB 300. This minimum value is what the sensor reads when the valve is in
a full
open position and the maximum A/D value can be used to close the valve
completely
off. Once the minimum and maximum values have been established, a user can be
prompted to position the pinion 112 at a location such that the spring force
within the
door closer 90 will try to force the pinion 112 back to its original starting
point. As
this occurs, calibration software will change the COS 164 position towards the
maximum A/D value with the expectation that some value prior to the maximum
A/D
value will indeed stop the pinion 112 from moving back to its original
starting point.
The value determined becomes the known A/D shutoff value that can be used for
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delayed action as well as the offset for initial values for sweep and latch
speeds. The
value is stored in memory for future normal door operation.
FIGs. 47 and 48 describe calibration routines that can be partially or fully
automated by software and can be used when a controller 110 is initially
fitted to a
door closer 90, when a controller 110 is replaced, or when a controller 110 is
retrofit
to an existing door closer 90.
FIG. 47 is a flowchart illustration of the process 2400 for arm gear 336
calibration according to some example embodiments of the invention. Process
2400
is shown partly in FIG. 47A and partly in FIG. 47B for clarity. Process 2400
begins
at block 2402 of FIG. 47A. At block 2403, the arm 94 of a door closer 90 being
calibrated is moved to the zero position. A user can move the arm 4 manually
and
then indicate its position through a connected workstation or with a button on
the
controller 110, for example, the teach button 350. Alternatively, a completely
computerized test bed can be used, wherein the arm 94 can be moved using, as
an
example, a robotic device. At block 2406, the zero position is set as the
initial jamb
position for the closer. At block 2408, the arm is moved clockwise to the 270
degree
position. Again, this movement, as all movements of the arm 94 described with
respect to FIG. 47, can be either by manual or automated means. This position
is then
stored at block 2410 as the maximum clockwise, or open position. The arm 94 is
then
moved ten degrees counter clockwise at block 2412.
Still referring to FIG. 47A, the current position at block 2414 is set with
the
positional value from an AID converter in the encoder as the maximum clockwise
value minus the result of ten degrees times the maximum counter clockwise
value,
and this positional value is stored in memory. The value in memory is
incremented
the known amount that equates to a change in encoder output value of one unit
at
block 2416, and a determination is made at block 2418 as to whether the known
maximum for the encoder has been reached. In this particular example, the
maximum
value is 54. If the value has not been reached, the value is incremented again
at block
2420 and this part of the process 2400 repeats. Otherwise, the current
position is set
at the maximum counterclockwise position and stored in memory at block 2422,
and
processing proceeds to FIG. 47B via off-page connector 2425.
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Turning to FIG. 47B, process 2400 continues from incoming off-page
connector 2428. The previous process is essentially repeated for the clockwise
direction with the movement of the arm by ten degrees at block 2430, resetting
the
value at block 2432, and determining at block 2434 if the maximum clockwise
value
for the encoder A/D converter has been reached. If not, at block 2436 this
part of the
process 2400 repeats. Otherwise, all A/D values and corresponding positions
for
counter-clockwise and clockwise rotation of the arm 94, or the pinion 112 that
is
coupled to the arm 94, are packed into memory at block 2438, that is, stored
in the
form of a table which effectively represents the calibration curve. Process
2400 then
ends at block 2440.
FIG. 48 is a flowchart illustrating a process 2500 for accomplishing
calibration
with respect to valve position. This process can be accomplished in parallel
or in
series with the arm calibration, and can be controlled by computer program
code
residing in the control unit 110 or elsewhere. In this example embodiment,
valve
position is recognized by reading the position of the COS 164, and the valve
is moved
by moving the COS 164. FIG. 48 is presented as Figures 48A, 48B and 48C for
clarity. Process 2500 begins at block 2502. At block 2504, the initial A/D
value is
read from the valve position (COS 164) encoder and the COS 164 is commanded to
move one increment or one "click." The COS 164 moves one click towards the
full
open position at block 2506. The initial value read above, ADX, is stored at
block
2508, and the new value, ADN, is stored at block 2510. As long as the original
value
stays less than the new value at block 2512, the values are equalized and the
COS 164
is moved one click and the new value stored at blocks 2514 and 2516,
respectively.
Otherwise, the last value is stored as the minimum positional value from the
A/D
converter in the encoder at block 2518, and the process continues to FIG. 48B
via off-
page connector 2520.
Turning to FIG. 48B, the process 2500 picks up from incoming off-page
connector 2522. The COS 164 is moved by the motor one click towards the closed
position at block 2523, and a similar process is repeated as the valve moves
towards
the closed position, with a check for movement by comparing the two values at
block
2526, a setting of the two values as equal at block 2528, and a movement of
the COS
164 by one click at block 2530. Once the two values are equal, it can be
assumed a
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mechanical stop has been hit at block 2532, and the last positional value is
stored in
EEPROM memory. At block 2534, the arm 94 is rotated, either manually or under
computer control, to 90 degrees to compress the spring 118 of the door closer
90. The
valve positional value from the encoder is read at block 2536, and the process
2500
proceeds to FIG. 48C via off-page connector 2538.
Turning to FIG. 48C, the process 2500 picks up at incoming off-page
connector 2540. The arm is released at block 2542. The COS 164 is moved one
click
towards the closed position at block 2544. Stored positional values, in this
case, AEN
and AEX, are again checked at block 2546, in this case, to see if the values
are equal.
If not, they are set to be equal at block 2548, and the COS 164 is incremented
at block
2549 and this part of the process repeats. Once they are equal, the current
positional
value is set as the value for the closed position of the valve at block 2552,
and this
part of the calibration process 2500 ends at block 2554.
Calibration as described above can be used to adjust a control unit for a
particular closer. However, the valve position can be adjusted to maintain
appropriate
closing forces as conditions vary in the field, or based on installation.
These
variations can even result from temperature changes or normal wear and tear.
Set
points of the valve can be dynamically changed while a closer is installed to
account
for these variations, thus obviating the need to manually adjust a closer at
regular
intervals. This feature may be referred to as "dynamically adjustable valve
set-
points."
In addition, the latch region can be dynamically adjusted by changing the
angle at which the latch region is encountered. In some circumstances, the
default
parameters for the final COS 164 position for close mode will not allow enough
momentum for complete closure of a door 82. Under this condition, and, in this
example embodiment, after eight consecutive occurrences, the control logic 580
will
then adjust the encoder angle that it normally sets for the final angle of
close, to occur
earlier in the cycle. The control logic 580 is preprogrammed to recognize
occurrences
of non-closure violations and adjust accordingly. This exemplary embodiment
currently uses three occurrences as the trigger point for adjustment to occur
and then
monitors for success. If problem persists, the adjustment will continue until
adjustment reaches a predefined limit of adjustment set by the factory. This
feature
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may be referred to a "dynamically adjustable latch position" or alternatively
as "latch
boost."
FIG. 49 is a flowchart that illustrates the operational method of a controller
according to at least some embodiments of the present invention. Again, FIG.
49
illustrates the method or process as a series of process or sub-process
blocks. The
process 2600 of FIG. 49 is illustrated in six parts for clarity. The six pages
of FIG. 49
on which the six parts of the flowchart are shown are designated as FIGs. 49A,
49B,
49C, 49D, 49E and 49F. Various portions of the flowchart are illustrated as
connected via off-page connectors, as is known in the art, with each pair of
connectors
being designated with a letter of the alphabet.
The process 2600 of FIG. 49 begins at block 2602. At block 2604, a
determination is made as to whether there is sufficient power to move the
motor 244
that controls the valve. If not, the controller simply waits. If so, the
controller, at
block 2606, reads the input switches (discussed below) to determine the
settings of the
door closer 90, and reads the ambient temperature from an on-board temperature
sensor. A determination is made at block 2610 as to whether the door 82 is
opening
or closing, based on readings of the hall effect sensors that have been
previously
discussed above. If the door is opening, the control unit sets the valve to a
"safe
close" position at block 2612, and the door is monitored at block 2614 to
determine if
the door reaches the set back check (BC) position. The back check position is
where
the door 82 begins to require the most force to open. In this example, the
back check
position is 65 degrees. If the door does not reach the back check position, it
will
begin to close at block 2616, with the same effect the logic as if the door
was closing
at determination block 2610. If the door does reach the back check position,
processing continues via the off-page connector designated "A" to FIG. 49D,
described in more detail below.
Continuing with FIG. 49 and referring to FIG. 49A, when the door is closing it
is monitored to determine at block 2618 whether it reaches the latch position.
The
latch position is the point in the swing or movement of a door where it is
close to
being closed, and the force is reduced, both so that the door is easier to
open at first,
and so that it closes with less force and is less likely to damage the frame,
injure a
person who might be in the doorway, and the like. By industry convention, a
door
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closer is typically designed so that the latch position is when the outward
edge of the
door is approximately 12 inches from the jamb. If the door 82 does not reach
latch
position when closing, processing proceeds via the off-page connector
designated "L"
to FIG. 49C, to be discussed below. If the door 82 does reach the latch
position, the
sweep time is recorded in memory at block 2620. The sweep time is the time it
takes
for the door to move from the fully open position to the latch position. The
controller
sets the valve to the latch position at block 2622 and the door 82 closes
towards the
jamb at block 2624. Processing then moves to FIG. 49B via the off-page
connector
designated "B".
FIG. 49B processing starts with a determination at block 2626 as to whether
the door actually reached the jamb, that is, whether the door closed the whole
way.
As will be appreciated from the discussion below, this determination is being
made
before the expiration of a time-out timer. If so, a determination is made at
block 2628
as to whether the latch angle is such that the door reached the latch region
when it was
nine inches away from the jamb. In this embodiment, nine inches is considered
the
smallest acceptable latch region. Despite the fact that the latch region is
specified as
distance of the edge of the door from the jamb, this distance may still
sometimes be
referred to informally as the "latch angle." If not, a counter stored in the
EEPROM
within the control unit is incremented by one at block 2630. This counter
keeps track
of how many times the door has closed successfully. At block 2632, a
determination
is made as to whether the door has successfully reached the jamb 10 times with
the
valve setting for where the latch region begins. The number of successful
closes
serves as a stored jamb success threshold. If so, the latch angle is adjusted
to subtract
two inches from the latch distance at block 2634. In either case the latch
time, that is,
the time required for the door to swing from the latch angle to jamb, is
recorded at
block 2636. At block 2638, any input switches and temperature are read by the
control unit, and processing proceeds to FIG. 49F via the connector designated
as "C"
in FIG. 49B. The switches, described in more detail below, are set by a user
and may
signal the control unit 110, for example, what type of installation the closer
is in,
whether delayed action is desired, where the back check region should be, and
the
like. Note that the control unit can take temperature into account in setting
the valve
to cause the behavior indicated by the switches.
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Staying with FIG. 49B, and returning to block 2626, if the door did not reach
the jamb at block 2626, a timer runs at block 2642. Once the timer has timed
out, a
determination is made at block 2644 as to whether the door is at the jamb. If
so,
processing again proceeds to block 2638. If the door has not reached jamb at
all, the
latch time is invalidated at block 2646. At block 2648, the valve setting for
the
current input switch position is changed in this example embodiment by five
clicks to
increase latch force, where a "click" is the minimum increment in which the
control
unit 110 is capable of adjusting the valve. The EEPROM is also updated. In
this
example embodiment, an EEPROM in the controller stores latch region
parameters.
Other types of memory and other devices can also be used in addition to or
instead of
an EEPROM. At block 2650, the jamb failure counter stored in the EEPROM is
incremented by one, and the success counter is set to zero. At block 2652 a
determination is made as to whether eight jamb failures have been recorded in
memory or the latch is at the minimum acceptable value. The number of jamb
failures in this case serves as a stored jamb failure threshold. In either
case, the
default valve set point is changed to the current set point at block 2654. A
determination is made at block 2656 as to whether the latch transition angle
is such
that the distance of the edge of the door from the jamb is 13 inches. If so,
the switches
and temperature are read at block 2638 and processing proceeds via the off-
page
connector designated "C". Otherwise, the latch angle is adjusted to add two
inches to
the distance of the door from the jamb where the latch region begins at block
2658,
prior to proceeding to block 2638.
Reviewing FIG. 49B, this portion of the operational flowchart for the control
unit 110 of embodiments of the present invention illustrates the latch boost
feature
previously referred to. Latch region parameters include, but may not be
limited to,
the latch region distance and the force on the door 82 in the latch region. If
the door
82 is failing to close, the valve position for the latch region of the door
can be
adjusted to alter the force on the door 82, and the beginning of the latch
region can
also be adjusted up or down by changing when the valve moves to the
appropriate set
point for the latch region of the door. The force on the door 82 in the latch
region can
serve as a first setting for the latch region from among the latch region
parameters.
The latch region definition, by door angle, or by distance of the edge of the
door 82
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from the jamb, can serve as a second setting from the latch region parameters.
These
settings can be reversed or otherwise occur at different points in the
operational
process of the controller, and either one or both can be based on a failure
count or a
success count. The adjustments to these latch region parameters can be made
dynamically and automatically, based on recorded successes or failures of the
door
closing to the jamb. Thus, as environmental conditions change, or mechanical
resistance of the door 82 or door closer 90 change with wear, the door closer
90 self-
adjusts these latch region parameters to maintain appropriate closing behavior
for the
door 82.
Turning to FIG. 49C, processing picks up at the off-page connector designated
"L" from FIG. 49A, where the door does not reach the latch region. At this
point, the
control unit programmatically presumes that the door is being held or is
otherwise
being prevented from closing normally. At block 2660, if a timer that checks
for the
maximum acceptable sweep time times out, that maximum acceptable sweep time is
invalidated at block 2662. In either case, at block 2664, the controller 110
begins
processing to determine how to handle the fact that power is not being
generated since
the door 82 is not moving. As long as there is sufficient power to operate the
control
unit, processing continues via the connector designated "M" to FIG. 49A where
sweep time is monitored. Once there is not enough power to run the controller
beyond a single move of the COS 164, the controller invalidates the current
sweep
time measurement at block 2666 and moves the valve to a safe close position at
block
2668 to ensure the door closes with a small enough force so as not to cause
injury or
damage, regardless of current conditions. If the door begins to move again a
determination is made at block 2670 as to whether it is opening or closing. If
the door
is opening, processing returns via the connector designated "D" to FIG. 49A,
where
the controller determines whether the door reaches the back check region. If
the door
is closing, a determination is again made at block 2671 as to whether there is
enough
power to begin to move the motor controlling the valve again. If not, the door
safely
closes at block 2672. Otherwise, processing returns to FIG. 49A at the
connector
designated "E" where the controller monitors the sweep and determines when/if
the
door reaches the latch position.
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Process 2600 in FIG. 49D picks up with the connector designated "J" which
leads from FIG. 49E, described in more detail below. FIG. 49D shows the part
of the
process that takes place when a closing door begins to open again, AND when
the
door closer is installed in a parallel mount configuration. As is known in the
door
closer art, door closers can be installed in different configurations. The
configuration
known as the "parallel mount" configuration refers to the configuration where
the
door closer is installed on the push side of a door. In this case, the door
closer arm 94
rests parallel to the door when the door is closed.
Still referring to FIG. 49D, at block 2674, a determination is made as to
whether the door has begun to close. If not, a determination is made at block
2676 as
to whether the door angle is greater than seventy degrees. If so, processing
proceeds
back to FIG. 49E via the connector designated "H". Otherwise, a determination
is
again made at block 2678 as to whether there is sufficient power to continue
to
operate the control unit 110. If so, the control unit 110 continues to
programmatically
monitor for the door 82 beginning to close. If there is insufficient power, as
before,
the valve is moved to a safe close position at block 2680. If the door
actually begins
to close at block 2674, a determination is also made as to whether there is
sufficient
power to run the control unit at block 2682, and if not, again, the valve is
moved to
the safe close position at block 2680. If the valve in the door closer 90 is
in the safe
close position and the door starts to close at block 2684, the power status of
the
control unit 110 continues to be monitored at block 2686. In either case, if
there is
sufficient power to run the control unit 110, the temperature and input switch
positions are checked at block 2688, and the valve is set to the close
position indicated
by the input switches and the temperature at block 2690, and processing
returns to
FIG. 49A via the connector designated "G".
Staying with FIG. 49D, processing can pick up at the connector designated
"A" from FIG. 49A, where the door reaches the back check region, such as at an
angle of 65 degrees. If there is sufficient power to move the valve at block
2692, the
valve is set for the back check region at block 2694 as indicated by the
appropriate
input switch. Otherwise, processing proceeds to block 2674. It cannot be
overemphasized that the positions of input switches, as well as the
temperature, can
change in the field, while the door closer 90 is installed, and the control
unit 110 can
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adapt to set the single rotary valve to an appropriate position for the
various operating
regions of the door with a door closer 90 according to an embodiment of the
invention. Thus, multiple, manually adjusted valves need not be used. Various
door
closer parameters can be taken into account, and changes in those parameters
made in
the field can be taken into account. As an example, door closer parameters
include
where the back check region begins, whether delayed action is selected and the
time
period for delayed action desired, and installation configuration. While not
user
configurable in the field in the exemplary embodiments described herein, latch
times
and regions, forces, sweep times, and the like may also be considered door
closer
parameters.
FIG. 49E describes the portion of process 2600 that deals with so-called
"delayed action" (DA) of the door closer 90. DA can be turned on for the door
closer
of the present embodiment by setting one of the input switches. With DA, the
door
pauses in an open position for a set amount of time prior to closing. The door
closer
of the present embodiment does not need any additional valves to implement
this
feature. The control unit 110 simply determines if the feature is turned on
and closes
the valve accordingly at, and for, the appropriate time. The control unit can
also sense
if the door is being pushed during the delay by sensing a voltage spike and
reacting
accordingly, adjusting the valve to allow the door to close without damaging
any of
the hydraulic components of the door closer.
Processing picks up in FIG. 49E at the connector designated "H" from FIG.
49D. At block 2696 a determination is made as to whether the input switch for
DA is
set to indicate that DA is desired. In this example embodiment, the switch has
three
positions (detents) one for DA off, and two for DA on, each one specifying a
different
hold time. If DA is not selected, processing proceeds to block 2698 where the
valve
is set to the appropriate close position. If so, however, a determination is
made at
block 2601 as to whether there is enough power for DA. If not, processing
again
moves to block 2698. If there is enough power, the valve is closed to stop
movement
of hydraulic fluid in the door closer at block 2603. At block 2605, a
determination is
made as to whether the door has been holding for the amount of time dictated
by the
input switch. If not, the available power is monitored at block 2607. If
either the time
has run, or there is insufficient power, processing immediately proceeds to
block
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2698. Otherwise, the door is monitored as mentioned above for a voltage spike
at
block 2609, and if a spike is detected, processing again proceeds to block
2698. If the
door closes without changing direction at block 2611, processing returns to
FIG. 49A
at the connector designated "I". Otherwise, if the door closer is in a
parallel mount
application at block 2615, as determined by reading the appropriate input
switch
during set-up in teaching mode, processing returns to FIG. 49D via the
connector
designated "J". If the door closer is not installed in a parallel mount
application,
processing returns to FIG. 49A via the connector designated "K".
FIG. 49F continues the process 2600, illustrating another aspect of the
previously discussed "latch boost" feature. In this case, latch parameters are
adjusted
to maintain the appropriate latch time rather than ensure the door closes to
the jamb
with the proper force. FIG. 49F also covers adjusting the sweep time based on
recorded times so that the door closer 90 is always operating as expected,
despite
current conditions and wear. Processing picks up in FIG. 49F either from FIG.
49C at
the connector designated "F" or from FIG. 49E with the connector designated
"C". In
the case of the connector designated "F" the control unit 110 simply proceeds
to the
end of the process 2600, block 2617. At block 2619, if the sweep time
previously
recorded is invalid, processing proceeds to block 2621, where a determination
is made
as to whether the previously recorded latch time was marked in memory as
invalid.
Otherwise, at block 2619 a determination is made at block 2625 as to whether
the last
recorded sweep time is outside of a hysteresis range. The hysteresis range is
a sweep
time slightly in excess of the maximum allowable sweep time that would be
permitted
for a single door operation from time to time, since an excess sweep time
might result
from human interference with the door, or some other completely temporary
situation.
If the sweep time is not outside the hysteresis range, processing again
proceeds to
block 2621. If the sweep time is outside of the hysteresis range, a valve
adjustment to
bring the sweep time back into range is calculated by the control unit 110 at
block
2627. If the calculated time is outside an absolute, allowable maximum at
block
2629, the sweep time is set to the absolute maximum at block 2631. Otherwise,
the
calculated time is used. In either case, the new sweep time is stored in the
EEPROM
within the control unit 110 at block 2633.
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Still referring to FIG. 49F, the latch time is dealt with in a manner similar
to
the sweep time above. At block 2621, if the latch time previously recorded is
invalid,
processing proceeds to block 2635, where all the latch and sweep timers are
reset for
the next time the door 82 is opened. Otherwise at block 2637, a determination
is
made as to whether the last recorded latch time is outside of a hysteresis
range. The
hysteresis range for the latch time is again simply a latch time slightly in
excess of the
maximum allowable latch time that would be permitted for a single door
operation
from time to time, since an excess latch time might result from human
interference
with the door, or some other completely temporary situation. If the latch time
is not
outside the hysteresis range, processing again proceeds to block 2635. If the
latch
time is outside of the hysteresis range, a valve adjustment to bring the latch
time back
into range is calculated by the control unit at block 2639. If the calculated
time is
outside an absolute, allowable maximum at block 2641, the latch time is set to
the
absolute maximum at block 2641. Otherwise, the calculated latch time is used
to set
the valve. In either case, the new latch time is stored in the EEPROM within
the
control unit at block 2645.
Staying with FIG. 49F, a determination is again made at block 2647 as to
whether the control unit 110 has sufficient power to maintain normal
operation. If not,
the valve is moved to the safe close position at block 2649. Otherwise the,
the control
unit 110 goes into a controlled sleep mode at block 2651, prior to process
2600 ending
at block 2617.
The foregoing description refers to input switches being read in order to
determine parameters for the door closer 90 operation set by a user. FIG. 50
illustrates an arrangement of user input switches that can be used with
embodiments
of the present invention. FIG. 50 shows a portion of the previously described
control
unit cover onto which a panel 2700 is fixed by screws 2701. The panel 2700
includes
a plurality of holes 2702 through which actuators 2704 protrude. Each actuator
includes a detent arm 2706 which engages with teeth (not shown) behind the
panel to
create a plurality of possible rotary positions for the actuators 2704 as
indicated by
numerical indicators that may be printed or scribed onto the panel 2700. Each
actuator defines a mounting hole, into which a magnet 2712 is secured.
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Still referring to FIG. 50, a circuit board 2720 is mounted inside the cover
behind the panel 2700. The circuit board 2720 includes magnetic sensors, such
as
Hall effect sensors (not shown), for each actuator. The hall effect sensors
sense the
magnetic field of the magnet through the cover to determine the position of
actuators
2704, and communicate this information to the other components of the
controller via
the control unit cable 292 (not shown). In this way, switches can be provided
for
actuation by a user, without additional openings in the cover of the control
unit 110
for cables or connectors.
Although the present invention has been shown and described in considerable
detail with respect to only a few exemplary embodiments thereof, it should be
understood by those skilled in the art that we do not intend to limit the
invention to
the embodiments since various modifications, omissions and additions may be
made
to the disclosed embodiments without materially departing from the novel
teachings
and advantages of the invention, particularly in light of the foregoing
teachings. For
example, some of the novel features of the present invention could be used
with any
type of hydraulic door closer. Accordingly, we intend to cover all such
modifications,
omission, additions and equivalents as may be included within the spirit and
scope of
the invention as defined by the following claims. In the claims, means-plus-
function
clauses are intended to cover the structures described herein as performing
the recited
function and not only structural equivalents but also equivalent structures.
Thus,
although a nail and a screw may not be structural equivalents in that a nail
employs a
cylindrical surface to secure wooden parts together, whereas a screw employs a
helical surface, in the environment of fastening wooden parts, a nail and a
screw may
be equivalent structures.
30
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