Note: Descriptions are shown in the official language in which they were submitted.
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ONE-WAY DRIVE FOR WINDOW COVERINGS
FIELD OF THE INVENTION
The present invention relates to an actuation system for a fenestration
product
adjustable covering, including a one-way drive mechanism used to reduce damage
to
the system due to a potentially damaging event during extension of the
covering.
BACKGROUND OF THE INVENTION
Within the art of fenestration products, such as windows and doors, it is well
known that double panes of glass in a window provide better insulation than a
single
pane of glass. The provision of venetian type blinds or pleated shades between
two
panes of glass in a fenestration product is also known in the art to provide
desired
window or door coverage. A pleated blind between window panes is disclosed in
the
U.S. Pat. No. 4,913,213 to Schnelker. A venetian or slat blind between panes
of glass
is disclosed in the U.S. Pat. Nos. 4,687,040; 4,664,169 and 5,379,825. In
order to
utilize such blinds or shades effectively with the increased insulation of the
double
glass product, control mechanisms for lifting, lowering and tilting the blind
or shade
from one side of the window must be provided while maintaining the window
seal.
The art has provided cords and cables, sometimes driven by a motor or gear
system,
as the control mechanism. The most popular systems route the cord through an
aperture drilled through the interior pane of glass.
U.S. Pat. No. 4,687,040 to Ball discloses a device for adjusting the tilt
angle of
slats of a slat blind positioned between the panes of glass. The device
includes a hole
in one pane of glass and a flexible cable passing through the hole. The cable
is
connected to a rectangular member which controls the rotation of the slats.
When the
cable is turned by external torque, the slats are tilted.
U.S. Pat. No. 4,913,213 discloses a pleated blind between double window
panes and blind control means for raising and lowering the blind. One
embodiment is
comprised of an aperture in one pane of glass and a bolt with a center hole
mounted in
the aperture. An actuator cord passes through the bolt hole and further up and
over a
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screen, if desired, thereby providing an external control mechanism.
U.S. Pat. No. 5,379,825 discloses a window blind between double panes of
glass. One embodiment uses a lift cord and a control cord routed through a
hollow
screw passing through one of the panes of glass to provide external control of
the
blind.
The prior art has also developed more complicated control mechanisms that
utilize cables and gear systems that pass through the window frame rather that
the
glass. U.S. Pat. No. 4,664,169 to Osaka et al. discloses a device for tilting
slats of a
venetian blind between double panes of glass. The device uses electrical power
driving means to move a piezoelectric bimorph device in a horizontal plane.
The
piezoelectric bimorph device is mounted to a block having a threaded bore. The
piezoelectric bimorph device mechanically moves an elongated V-shaped beam
under
two cross arms which control the rotation of the slats. When the beam is
moved, the
cross arms are tilted, thereby rotating the slats.
The complicated systems that require control mechanisms to be mounted in or
routed through the window frame are relatively expensive to manufacture.
Furthermore, in many of these systems gears and motors wear and then slip or
fail.
Many of these control devices require a head rail which is too wide to fit
between the
panes of those windows whose panes are not more than 3/4 inches apart. Hence,
these
systems have never achieved the popularity of through the glass systems.
The problems of the prior art systems discussed above are not present if the
control mechanism is a. cord or cords routed between the edge of the interior
glass
panel and the window frame. In U.S. Pat. No. 4,913,213, Schnelker describes a
pleated blind between window panes. In one preferred embodiment, the actuator
cord
is routed over the glass housing and any screen housing provided. An L-shaped
guide
having a single vertical and horizontal channel cut therein is fitted over the
top edge
of the glass housing. An actuator cord passes through the channel. A major
problem
with this system is that one cannot maintain a seal between the window frame
and the
edge of the glass housing. Another problem is that most blinds have four
control
cords, two lift cords and two tilt cords. If all four cords are routed through
a single
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channel they tend to bind and interfere with one another.
In U.S. Pat. Nos. 5,611,381, 6,006,813 and 6,070,638, Jelic describes a
window having a blind between two panes of glass. A cord guide is provided at
the
top edge of the housing, with the cord guide including multiple slots for the
lift and
tilt cords. The cord guide maintains a seal between the window frame and the
window
panes and keeps the cords separated. However, in this window system, the blind
is
still controlled by multiple cords routed around the window panes, which still
tend to
present problems for the user.
Even when the cord routing has been improved, between the glass window
covering product may still have problems, such as jamming, when the lift cords
experience slack during operation. These problems may occur when the lift
mechanism is used too briskly or quickly, or when the window covering
encounters
some type of obstruction. With the blind located between two glass panels,
resolution
of a jam in the lift cord is not an easy matter. Therefore, lift cord systems
and blind
actuation mechanisms that reduce the risk of slack and jamming are preferred.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a covering actuation system for an adjustable
covering used with a fenestration product. The covering actuation system is
configured to extend and contract the covering upon operation of a covering
operator
by a user to provide varying amounts of viewing coverage through the
fenestration
product. The covering actuation system includes a lift mechanism coupled to
the
operator such that operation of the operator by a user results in the
extension and
contraction of the covering by action of the lift mechanism. The lift
mechanism also
includes a drive system configured to temporarily decouple and later recouple
the lift
mechanism from the operator. The drive system is activated by a potentially
damaging event during extension of the covering so as to reduce damage to the
lift
mechanism. The potentially damaging event may includes slack in a lift cord
during
extension of the covering. The drive system is configured to retain rotational
registration between multiple components of the lift mechanism upon recoupling
of
the lift mechanism to the operator.
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The present invention also provides a method of reducing damage to an
actuation system for an adjustable covering usable with a fenestration product
during
a potentially damaging event. The actuation system includes a lift mechanism
configured to extend and contract the covering by operation of an operator.
The
S method includes the step of decoupling the lift mechanism from the operator
during a
potentially damaging event while extending the covering. The method further
includes the step of recoupling the lift mechanism to the operator after
decoupling the
same.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a front, interior view of a fenestration product, such as a window,
including a between the glass window covering and an interior insect screen.
FIG. 2 is a partial detail view of the window of FIG. 1.
FIG. 3 is a front, interior view of a window panel removed from a window
frame, including one embodiment of a sliding operator for a between-the-glass
window covering in accordance with the present invention.
FIG. 4 is a partial, cut-away view of the panel of FIG. 3.
FIG. 5 is a partial detail view of the panel of FIG. 3 showing a through-the-
glass shaft.
FIG. 6 is front, interior view of window panel, including another embodiment
of a sliding operator for a between-the-glass window covering in accordance
with the
present invention.
FIG. 7 is an exploded view of one embodiment of the handle portion of a
sliding operator in accordance with the present invention.
FIG. 8 is an exploded view of one embodiment of the pulley and shaft portion
of a sliding operator in accordance with the present invention.
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FIG. 9 is an back, exterior view of a window panel including a between-the-
glass blind and one embodiment of a window covering actuation system in
accordance with the present invention.
5 FIG. 10 is a detail, exterior view of a window covering actuation system.
FIG. 11 is a detail, interior view of the window covering actuation system of
FIG. 10.
FIG. 12 is an exploded view of one embodiment of a gear box usable with a
window covering actuation system in accordance with the present invention.
FIG. 13 is a perspective view of another embodiment of a gear box usable
with a window covering actuation system in accordance with the present
invention.
FIG. 14 is an exploded view of the gear box of FIG. 13.
FIG. 15 is a partial detail, exterior view of a window covering actuation
system, including a lift spool, tilt drum and clutch/brake assembly.
FIG. 16 is an exploded view of the clutch/brake assembly of FIG. 16.
FIG. 17 is a partial detail, exterior view of a window covering actuation
system, including a tilt drum and gear box.
FIG. 18 is a partial detail, exterior view of an alternative window covering
actuation system, including another embodiment of a tilt drum and another
embodiment of a gear box.
FIG. 19 is a partial detail view of one embodiment of a bottom rail of a blind
usable as a between-the-glass window covering, including a lift cord
adjustment
system.
FIG. 20 is a perspective view of a window panel and interior insect screen
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attachable to the window panel in accordance with the present invention,
including a
sliding screen operator that engages the sliding operator on the panel.
FIG. 21 is a partial detail interior view of the screen and panel combination
S shown in FIG. 21.
FIG. 22 is a partial detail exterior view of the screen of FIGS. 20 and 21.
FIG. 23 is an exploded view of one embodiment of a drive assembly usable
with the screen sliding operator shown in FIGS. 21-23.
FIG. 24 is an exploded detail view of one embodiment of a coupler, as shown
in FIGS. 20-22.
FIG. 25 is an exterior, detail view of another embodiment of a window
covering actuation system, including an alternative embodiment of a lift spool
drive
system.
FIG. 26 is a detail view of the lift spool drive system of FIG. 25, shown with
a
spool shroud and cradle.
FIG. 27 is an exploded view of the lift spool drive system of FIG. 26.
DETAILED DESCRIPTION OF THE INVENTION
With reference to the attached Figures, it is to be understood that like
components are labeled with like numerals throughout the several Figures.
FIGS. 1
and 2 are a fenestration product 40 to be used in accordance with the present
invention having multiple panes of viewing material, including an exterior
pane 41
and an interior pane 42, and an optional interior insect screen 44, all set
within a
window frame 46. One or more additional panes of viewing material, such as
double
pane 43, may also be provided as needed to meet the efficiency and esthetic
requirements of the fenestration product 40. As used herein, the term "viewing
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material" refers to organic or inorganic materials that provide at least a
partial barrier
to the elements through which light can pass, including for example glass,
plexiglass,
screening materials, and the like. The viewing materials can be transparent,
translucent, or partially opaque. Due to long-standing usage in the art, the
terms
"glass" and "pane" are synonymous with the term viewing material.
The panes of viewing material 41, 42, 43 are mounted within a sash 50 having
a sash head 51, a sash sill 52 and sash jambs 53. The sash 50 is moveable to
open the
fenestration product 40 to allow for air flow into a building in which the
fenestration
product 40 is mounted. A handle 45 is commonly used to open and close the sash
50,
when desired. Positioned between the exterior and interior panes of viewing
material,
41 and 42, respectively, is a window covering 70 that may be adjusted by
extending
or contracting the covering 70 and/or by tilting components, such as slats 72,
of the
covering 70. Although the disclosed primarily between two sheets of viewing
material, the present window covering 70 can also be used on the interior side
of a
fenestration product 40 adjacent a single pane of viewing material.
Although shown as a casement window, the fenestration product 40 may be
any of a munber of types products having windows, including but not limited to
openable and non-openable windows, double-hung windows, windows within doors,
sliding glass or patio doors, or other windows now known or later developed to
be
mounted in an architectural opening within a building. Although shown as a
horizontal slat blind, it is to be understood that the window covering 70 may
be any of
a number of types of window coverings, including but not limited to horizontal
blinds,
vertical blinds, or other types of blinds, roman shades, pleated shades,
honeycomb
shades or other types of shades, any of which are capable of being extended
and/or
contracted to provide a desired amount of coverage for the window, and may be
adjusted by tilting slats or other components of the covering. The window
covering
may be constructed from materials that are opaque, partially opaque, or
translucent.
For certain applications, the window covering may be constructed from a
transparent
material that is treated to block certain wavelengths of electromagnetic
radiation, such
as ultraviolet.
Referring now also to FIGS. 3 and 4, in this embodiment of the fenestration
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product 40, the sash 50 includes a removable glass panel 60, commonly know in
the
industry as a double glazing panel or DGP. The glass panel 60 includes the
interior
glass pane 42 mounted within a panel frame 69 having a panel head 61, panel
sill 62
and panel jambs or side walls 63.
Referring now also to FIGS. 3 and 4, the glass panel 60 is shown removed
from the window frame 46 and without the optional screen 44, with an interior
side 66
of the glass panel 60 facing forward. As used herein, the term "interior"
generally
refers to the side of the fenestration product inside a dwelling or other
building and
the term exterior generally refers to the outdoor side of the product.
However, when
the fenestration product is mounted totally inside a building, such as door or
window
between two indoor rooms (for example, an office door or window), then
interior
refers to the side of the product at which a user would normally operate the
product or
a window covering for the product and exterior refers to the opposite side.
Multiple
retractable tabs 65 are provided to secure the glass panel 60 within the sash
50.
Along one panel jamb 63, (in this embodiment shown on the left side of the
glass panel 60, however the other side may also be used), a sliding operator
80 is
provided to control the extension/contraction and/or other adjustment of the
window
covering 70. The sliding operator 80 may be installed within the panel jamb 63
during
formation of the glass panel 60 or, alternatively, the sliding operator 80 may
be
provided as an add-on accessory and attached to the panel jamb 63. In the
latter
situation, existing fenestration products 40 already installed in buildings
may be
retrofit with the present invention for added versatility for a consumer.
The sliding operator 80 includes a handle 87 that slidably moves along a slide
channel 85 formed with a panel jamb 63. Although shown in one position that is
generally perpendicular to the glass pane 42, the handle 87 may be
repositioned
generally parallel to the glass pane 42, if desired, or may be placed in any
other
suitable position or location for manipulation and control of the slide
channel 85. The
handle 87 is connected to a drive mechanism 86, such that generally linear
movement
of the handle 87 along the slide channel 85 results in movement of the drive
mechanism 86. In one embodiment, the drive mechanism 86 includes a belt, such
as a
timing belt that may or may not include teeth. The belt 86 is shown mounted
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perpendicular to the glass pane 42, however other mounting configurations are
also
possible. Optionally, the drive mechanism 86 may be, but is not limited to, a
chain,
perforated tape, rope, cord, or other suitable driving component.
At an intersection of panel jamb 63 and the panel head 61, a pulley enclosure
81 is mounted. Referring now also to FIG. 5, within the pulley enclosure is a
sprocket
83 mounted to a shaft portion 82 that extends through an aperture 45 in the
glass pane
42. Driving mechanism 86 is routed around shaft pulley 83 such that the shaft
pulley
83 engages the driving mechanism 86. Movement of the driving mechanism 86, by
sliding movement of handle 87, thus results in rotation of shaft portion 82. A
seal 89
is configured around shaft portion 82 to maintain the integrity of space
between the
glass panes 52.
Drive mechanism 86 is routed about a pair of pulleys 84, also mounted within
pulley enclosure 81, which guide the drive mechanism 86 from the shaft pulley
83
toward the slide channel 85. In this embodiment, guiding of the drive
mechanism 86
by the pulleys 84 results in about a 90 degree direction change for the
driving
mechanism 86. Adjacent to the panel sill 62, a third pulley 88 is positioned
so that the
drive mechanism 86 routes around it at an opposite end of the glass panel 60.
In this
embodiment, the drive mechanism 86 is configured as a continuous loop, however
other configurations are also possible and within the scope of the present
invention.
Referring to FIG. 6, an alternative embodiment of a sliding operator 180 of
the
present invention is shown for a removable glass panel 160 including glass
pane 142.
In this embodiment, the sliding operator 180 is mounted to the glass pane 142,
instead
of being configured as part of a panel jamb, such as jamb 63 as described
above. The
sliding operator 180 includes a slide channel 185 in which a driving mechanism
186 is
routed. A handle 187 slides along slide channel 185 providing movement of the
driving mechanism 186.
Adjacent panel head 161, a pulley enclosure 181 is mounted such that the
drive mechanism 186 is routed around a shaft pulley 183 and a pair of pulleys
184.
The shaft pulley 183 is mounted on a shaft 182 that passes through the glass
pane 142.
In this embodiment, with the sliding operator 180 mounted on the glass pane
142, the
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sliding operator 180 may be substantially aligned with the shaft 182, thereby
removing the need for a 90 degree direction change of the driving mechanism
186, as
was described above with respect to driving mechanism 86.
5 Adjacent panel sill 162, a second pulley enclosure 190 is mounted to the
glass
pane 142. Within this second pulley enclosure 190, a second pair of pulleys
192 and a
third pulley 191 are positioned to route the drive mechanism 186 in an aligned
manner
with respect to the first pulley enclosure 181 and the shaft 182. In one
embodiment,
the drive mechanism 186 forms a continuous loop by attachment at the handle
187,
10 such that movement of the handle 187 generally parallel to the member 163
results in
smooth, direct movement of the drive mechanism 186 and rotation of the shaft
182.
Although the sliding operator 180 will partially obstruct the view through the
glass pane 142 to some extent, in contrast to the offset sliding operator 80
located on a
panel jamb 63, the on-glass sliding operator 180 has other advantages. In
particular,
although the sliding operator 180 mounted to the glass pane 142 may be used
with
any type of fenestration product, it is especially useful with sliding glass
doors,
double-hung type windows or other sliding-type fenestration products. The on-
glass
mounting of the sliding operator 180 provides a lower profile for the
fenestration
product, and thus accommodates the passing of one component of a fenestration
product relative to a closely adjacent component of that fenestration product.
Referring to FIGS. 7 and 8, another alternative embodiment of a sliding
operator 280 is shown including a slide channel 285 in which a driving
mechanism
286 is routed. In this embodiment, the drive mechanism 286 is a timing belt. A
handle
287 slides along slide channel 285 providing movement of the timing belt 286.
A
bracket 288 that mates with the timing belt 286 clamps the ends of the timing
belt 286
at the handle 287 using fasteners 289, thereby forming a continuous loop of
timing
belt 286 throughout the sliding operator 280. A lower pulley 290 is secured by
fastener 293 within a housing 291 that has a back plate 292 and is attached to
one end
of the slide channel 285. The lower pulley 290 is mountable at or near the
panel sill
(not shown). The timing belt 286 is routed around the lower pulley 290 forming
the
lower end of the timing belt loop. The lower pulley 290 is adjustable within
the
housing 291 by rotation of fastener 293, such that movement of the lower
pulley 290
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toward and away from the panel sill (not shown) adjusts the tension within the
timing
belt 286 for efficient operation of the sliding operator 280.
A pulley enclosure 281 attached to the other end of the slide channel 285 is
mountable adjacent a panel head (not shown) at an opposite end from the lower
pulley
290. The timing belt 286 is routed around a corresponding timing belt sprocket
283
and a pair of pulleys 284 mounted within a pulley housing 296 that is enclosed
by
cover 294. The sprocket 283 is mountable to a shaft (not shown), such as
previously
described shaft portion 82 that passes through the glass pane 42. In this
embodiment,
the sprocket 283 is mounted on bearings 295 within a shaft housing 297 to
facilitate
routing and function of the timing belt 286, which is also aided by roller 299
attached
by pin 298 to the shaft housing 297.
Referring now to FIG. 9, an exterior side 67 of glass panel 60 is shown with a
horizontal blind 90 attached. A sealing member 68 is provided around the
circumference of the glass panel 60 in order to seal the glass panel 60 to the
sash 50
when the glass panel 60 is secured to the sash 50 by retractable tabs 65. The
blind 90
includes a plurality of slats 91 that extend generally from one panel jamb 63
to the
other with enough slats 91 to extend generally from the panel sill 62 (not
shown) to an
area adjacent the panel head 61 when the blind 90 is about fully extended. For
clarity
in this figure, only a portion of the plurality of slats 91 are shown. It is
to be
understood, that different configurations of blinds may also be used in
keeping with
the present invention.
In this embodiment, the plurality of slats 91 may be contracted by retraction
of
a plurality of lift cords 92, as will be described in more detail below. The
plurality of
slats 91 may also be rotated or tilted from a generally horizontal position
(as shown)
to an angled orientation that is somewhat less than vertical, in either
direction, by
movement of a plurality of ladder cords 93, which will also be described in
more
detail below. Extension/contraction and angular adjustment or tilting of the
blind slats
91 allows an operator to provide desired light passage through and coverage of
the
glass pane 42 of the fenestration product 40.
Referring now also to FIGS. 10 and 11, the blind 90 or other window covering
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is attached to a window covering actuation system 200 mounted to the glass
panel 60
at a head channel 204 adjacent the panel head 61. The head channel 200 has a
general
'L' shaped cross-section formed by a sidewall 205 and a shelf 207. The
sidewall 205
includes an upper hook 206 to aid in mounting the head channel 200 to the
panel head
61. The shelf 207 includes a toe portion 208 for retaining components 203 of
the
actuation system 200 in the head channel 204 and, optionally, for connecting
these
components 203 to the head channel 204.
As shown in FIG. 11, on an interior side 202 of the head channel 204, the
sidewall 205 is a generally flat wall providing a uniform and plain appearance
to the
interior of a dwelling or other building for an indoor viewer. Thus, an
operator of the
blind 90 or a viewer of or through the fenestration product 40 does not see
the
components 203 of the actuation system 200, thereby providing a more pleasing
appearance to the fenestration product 40. As shown in FIG. 10, however, on an
exterior side 201 of the head channel 204, the components 203 may be exposed
or
may optionally be covered by another wall (not shown) coupled to the toe 208,
the
shelf 207 or one or more of the components 203.
In this embodiment, the components 203 of the actuation system 200 include
two driving shafts, a rotating lift shaft 210 and a rotating tilt shaft 212.
For
embodiments using a only a non-tilting window covering, such as a shade, the
tilt
shaft 212 may be eliminated or provided, but not utilized. The components 203
also
include a gear box 220 mounted to the head channel 204 and coupled to at least
the
lift shafts 210 at a first end 214. The actuation system 200 connects to shaft
82 at gear
box 220, the shaft 82 passing through the glass pane 42. The shaft 82, in
turn, is
coupled to and driven by sliding operator 80, such that linear motion of
sliding
operator 80 results in rotational motion of shaft 82 and corresponding
operation of the
actuation system 200 by rotational motion of lift shaft 210.
Referring now to FIG. 12, one embodiment of the gear box 220 is shown in an
exploded view. The gear box 220 includes a housing 221 with a cover 222. A
shaft
223 incorporates shaft portion 82 that protrudes through the glass pane 42, as
described above. Shaft 223 also includes a first bevel gear 224 mounted to or
formed
with the shaft 223. A second bevel gear 225 is mounted with the housing 221 to
mate
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with the first bevel gear 224. A first spur gear 226 is coupled to, or formed
with, the
second bevel gear 225, with the combined gears 225, 226 mounted within the
housing
221 so as to provide an external interface 227 for lift shaft 210. A second
spur gear
228 is also mounted within the housing 221 in a mating relationship with the
first spur
gear 227 and so as to provide an external interface 229 for tilt shaft 212. In
operation,
when protruding shaft portion 82 is rotated, rotation of shaft 223 and the
first bevel
gear 224 results in rotation of lift shaft 210. This rotation produces a
corresponding
rotation in the tilt shaft 212 through the spur gear set 226, 227.
The combination of the bevel gears 224, 225 and sliding operator 80
preferably includes an amount of gear reduction, such that a full range of
motion of
the window covering 90 is achieved by relatively less motion of the sliding
operator
80. In one embodiment, this ratio of handle travel to covering travel is about
70
percent. The gear ratio of the gears 224, 225 contributes in part to this
travel ratio.
However, also contributing to this travel ratio is the relationship of the
sliding
operator 80 structure to the covering actuation structure, as described below.
Referring to FIGS. 13 and 14, an alternative embodiment of a gear box 230 is
shown including a housing 231 and a cover 232. A shaft 233 incorporates shaft
portion 82 and a first bevel gear 234. A second bevel gear 235 is mounted to
mate
with the first bevel gear 234 and provide an external interface 237 for the
lift shaft
210. One or more bearings 236 supports the external interface 237 within the
housing
231. A first ball bearing 238 and a second ball bearing 239 are also provided
to
support shaft 233 within the housing 231. In this embodiment, spur gears or
other
coupling mechanisms are not provided as part of the gear box 230 to couple the
rotation of the lift shaft 210 to the rotation of the tilt shaft 212. Instead,
this coupling
is provided as another component 203 of the actuation mechanism 200, as
described
below.
Referring again to FIG. 10, the actuation system 200 also includes a plurality
of lift spool assemblies 240, preferably in a number equal to the number of
lift cords
92 of blind 90. Each lift spool assembly 240 includes a lift spool 241 mounted
on a
support cradle 242 mounted to and supported by the head channel 204. The lift
shaft
210 passes through each lift spool 241 with the lift spool 241 coupled to the
lift shaft
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210 so that rotation of the lift shaft 210 results in corresponding rotation
of the lift
spool 241.
A protective shroud 243 is preferably positioned over the lift spool 241 to
protect the spool 241 and lift cord 92 during operation, such as from
dirt/dust
contamination. In addition, the shroud 243 keeps the lift cord 92 on the spool
241 in
the desired location, thereby minimizing unwanted unwinding and tangling of
the lift
cord 92. As the spool 241 rotates, it shifts back and forth along the lift
shaft 210 with
respect to the location of the lift cord 92. As a result, the lift spool 241
retracts into
and emerges out of the shroud 243 as the lift cord 92 winds up or unwinds. The
protective shroud 243 is optionally positioned over only a portion of the lift
spool
241. For example, the protective shroud 243 can be a discontinuous
configuration,
such as a plurality of elongated members or a perforated structure.
The actuation system 200 further includes a plurality of tilt drum assemblies
250, preferably in a number equal to the number of ladder cords 93. Each tilt
drum
assembly 250 includes a tilt drum 252 supported by a tilt drum support cradle
251
mounted to the head channel 204. The tilt shaft 212 passes through each tilt
drum 252
with the tilt drum 252 coupled to the tilt shaft 212 such that rotation of the
tilt shaft
212 results in corresponding rotation of the tilt drum 252. Each tilt drum
assembly
250 is positioned adjacent to a lift spool assembly 240 to facilitate routing
of the
adjacent lift cords 92 and ladder cords 93 from the blind 90, as will be
described in
more detail below.
Referring now to FIG. 15, one embodiment of a lift spool 241 is mounted
adjacent tilt drum assembly 250 that includes tilt drum support cradle 251.
The lift
spool 241 has a spiral groove or thread 244 (of which only a portion is shown
for
clarity) about which the lift cord 92 winds and unwinds upon rotation of the
lift shaft
210 during operation of the actuation system 200. The cradle 251 includes a
pair of
support legs 253 positioned at either end of the tilt drum 252. The lift cord
92 passes
from the lift spool 241 adjacent the tilt drum 252 and through an aperture 209
formed
within the shelf 207 of head channel 204, along with the ladder cords 93.
In order to accommodate the routing requirements of the lift cord 92,
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including its passage through aperture 209, the lift cord 92 is preferably
formed from
monofilament material, including but not limited to fluorocarbon, nylon, and
polyester. The monofilament produces less friction than conventional cordage
materials used for window coverings, thus resulting in less binding and
snagging of
the lift cord 92 during operation of the window covering 90. In addition, use
of
monofilament material results in less wear and thus longer life for the lift
cords 92,
thereby increasing the overall life of the window covering 90 itself.
As the lift shaft 210 rotates, the lift spool 241 also rotates causing the
lift cord
10 92 to wind up or unwind about the spool 241, depending on the direction of
rotation.
With the lift cord 92 attached to a lower most slat or bottom rail 97 of the
blind 90,
movement of the lift cord 92 results in retraction or extension, respectively,
of the
blind 90. In order to control the rotation of the lift shaft 210 in both
directions, a
clutch/brake mechanism 270 is coupled to the lift shaft 210 at a second end
215. In
15 this embodiment, the clutchlbrake mechanism 270 is supported by a mechanism
support 271 mounted to the head channel 204 at shelf 207. In one embodiment,
the
clutch/brake mechanism 270 is a spring clutch, however, other types or
configurations
of clutch and brake mechanisms may also be used.
Referring now also to FIG. 16, clutch/brake mechanism 270 includes not only
a first shaft mounting 272 for lift shaft 210, but also a second shaft
mounting 274 for
tilt shaft 212. First shaft mounting 272 is provided within first spur gear
273, which is
in turn adjacent to and engaged with a second spur gear 275 that includes
second shaft
mounting 274. As lift shaft 210 rotates and is controlled by clutch/brake
mechanism
270, rotation of the first spur gear 272 causes a corresponding rotation in
second spur
gear 275, resulting in rotation of the tilt shaft 212.
Clutch/brake mechanism 270 also includes the support housing 271 that is
mountable to the head channel 204. Configured to mount within the support
housing
271 are a clutch drum 276, coupled to a brake drum 278. The brake drum 278
also
couples with a brake spring 279 that is, in turn, keyed to the support housing
271. The
clutch drum 276 also couples to a clutch spring 277 that is in frictional
contact with
the brake drum 278 and the clutch drum 276. When the window covering 90 is
being
lowered or trying to lower itself under its own weight, the clutch spring 277
cinches
CA 02467548 2004-06-18
16
down on the brake drum 278, resulting in the rotation of the brake drum 278
and
subsequent cinching of the brake spring 279. The brake spring 279 applies
enough
resistance to prevent the window covering 90 from dropping under its own
weight,
but does not inhibit deliberate lowering of the window covering 90 by a user
using the
slide operator 80. When the window covering 90 is being raised or operated in
the
other direction, the clutch spring 277 spreads open, disengaging the brake
drum 278
from the clutch drum 276. Alternatively, the engagement between the lift shaft
210
and tilt shaft 212 may occur at the gear box, as will be described in more
detail below
with respect to FIGS. 17 and 18.
As described above, each tilt drum assembly 250 is preferably positioned
adjacent a lift spool assembly 240 to facilitate routing of the lift and
ladder cords 92,
93, as stated above. Referring now also to FIG. 17, one of the tilt drum
assemblies
250 is shown with ladder cord 93 attached, but with the adjacent lift spool
assembly
240 not shown for clarity. The ladder cord 93 includes two side cords 94 and a
plurality of cross cords 95 spanning between the side cords 94 and positioned
under
each blind slat 91. The side cords 94 extend upward through aperture 209
formed
within the shelf 207 of head channel 204. In one embodiment, these two cords
94 are
wrapped around the tilt drum 252 from opposite sides, but are not secured to
the drum
252. Alternatively, the cords 94 may be secured to tilt drum 252, if desired.
The
ladder cords 93 are preferably formed from conventional materials, including
but not
limited to braided polyester.
When the tilt drum 252 is rotated by rotation of the tilt shaft 212, one side
cord
94 will lift upward and the other cord 94 will move downward. As a result, the
cross
cord 95 will tilt, causing the slat 91 supported by the cross cord 95 to tilt,
as well.
Depending on the direction of rotation of the shaft 212 and drum 252, the slat
91 will
tilt in either direction.
As was described above, in the present invention, rotation of the tilt shaft
212
results from rotation of the lift shaft 210 due to coupling of the shafts 210,
212
together, such as by gears located at the clutch/brake mechanism or at the
gear box. In
the embodiment shown in FIG. 17, this coupling of the lift and tilt shafts
210, 212
occurs at a gear box 260 that includes a first gear (not shown) mounted to
lift shaft
CA 02467548 2004-06-18
17
210 within a housing 261 and a second gear 265 mounted to tilt shaft 212 and
coupled
to the first gear. The lift shaft 210 may rotate around many times during the
raising
and/or lowering of the blind slats 91. However, only partial rotation of the
tilt shaft
212 and tilt drum 252 are necessary to produce the desired amount of tilt for
the blind
slats 91. In order to accommodate the different rotational requirements of the
lift and
tilt systems, the side cords 94 are wrapped about the tilt drum 252 in such a
way that
there is enough friction between the drum 252 and cords 94 to tilt the slats
91 as the
drum 252 rotates. However, there is not enough friction to prevent the drum
252 from
continuing to rotate after the slats 91 have tilted to their limit, in one
direction or the
other. Reversing rotation of the lift shaft 210 will repeat the process in the
opposite
direction.
Referring to FIG. 18, an alternative embodiment is shown in which the ladder
cord 93 is attached to a tilt drum 292 at side cords 94. In order to
accommodate full
rotation of the lift shaft 210, an alternative gear box 280 is provided
including a first
spur gear 286 coupled to the lift shaft 210 and a second spur gear 288 coupled
to the
tilt shaft 212. In this embodiment, the second spur gear 288 includes a
circumferential
toothless area 289 without gear teeth. The second spur gear 288 is positioned
relative
to the first spur gear 286, such that the second spur gear 288 reaches the
toothless area
298 at a tilt limit of the slats 91, thus allowing the first spur gear 286 and
lift shaft 210
to continue rotating without rotating the tilt shaft 212 or drum 252. In a
like manner, a
reversal of direction by the lift shaft 210 results in tilt movement of the
slat 91 in the
opposite direction until the other tilt limit is reached. As would be apparent
to one of
skill in the art, other mechanisms for coupling the tilt drum 252 and tilt
shaft 212 to
the lift shaft 210 to achieve the desired range of motion are also possible
and are
within the spirit and scope of the present invention.
The present invention provides a fenestration product having a window
covering that is operated and adjusted by a sliding operator on the interior
side of the
product. No interior cords are provided or required to operate or adjust the
window
covering. The window covering of the present invention is particularly well
suited for
between-the-glass applications, but can also be used on the interior of a
fenestration
product. The present invention thus simplifies the window covering's operation
and
eliminates unsightly and potentially hazardous cords. By operation of the
single
CA 02467548 2004-06-18
18
sliding operator, both expansion/contraction and tilt adjustment of the window
covering may be achieved.
With many types of window coverings usable with a fenestration product, lift
or contraction of the covering is achieved by using lift cords, such as lift
cords 92
described above. In the situation where control cords are provided, the
control cords
are commonly usable to adjust both the position and level of the bottom rail,
such as
bottom rail 97 shown in FIG. 9. If one lift cord is shortened or lengthened
differently
than one or more other lift cords, the level of the bottom rail will be
affected and it
will not be generally horizontal. Level adjustment of the bottom rail usually
then
requires adjustment of the lift cords by the control cords. However, for
window
coverings without external cord control, such as those used in conjunction
with the
present invention, leveling of the bottom rail may be difficult to manage.
Referring now to FIG. 19, one embodiment of a bottom rail 300 is shown,
including a bottom rail channel 301. For standard window coverings (not
shown), the
lift cords are knotted or otherwise secured within the bottom rail channel 301
requiring adjustments to the cords to be made at drive system at the top of
the window
covering. In this embodiment, each lift cord 302 enters the bottom rail
channel 301
and passes through a T-plug 303 that routes the lift cord 302 in about a 90
degree
direction change, generally from vertical to horizontal. In addition, the T-
plug 303
may be used to secure a corresponding ladder cord (not shown) to the bottom
rail 300.
In one embodiment, the bottom rail channel 301 is covered by a lowest slat
(not
shown) of the window covering
From the T-plug 303, the lift cord 302 is routed to and attached to a cord
adjuster 304. For window coverings having multiple lift cords 302, multiple
cord
adjusters 304 may be provided. For window coverings with two cords 304, two
cord
adjusters 304 are provided, preferably with one at each end of the bottom rail
300. For
wider window coverings normally having four lift cords 304, four cord
adjusters 304
are provided, preferably with two at each end, as shown. The cord adjuster 304
is
configured to move in at least one direction, so as to pull on the attached
lift cord 302.
Optionally, the cord adjuster 304 may be configured to move in two directions,
so as
to provide more versatility in adjustment and/or readjustment of the lift cord
304 and,
CA 02467548 2004-06-18
19
thus, the level of the bottom rail 300. Cord adjuster 304 may be formed as a
strip, rod
or other suitable item for attachment to the lift cord 302 and adjustable
movement
within the bottom rail channel 301. In one embodiment, as shown in FIG. 20,
the cord
adjuster 304 is a strip having notches or teeth 305, such as a zip tie.
Cord adjuster 304 is mounted within bottom rail channel 301 adjacent to and
engaged with a locking mechanism 306. Locking mechanism 306 is configured to
allow the cord adjuster 304 to move in one direction and to prevent movement
in the
other direction. Alternatively, the locking mechanism 306 may be configured
for
releasable engagement of the cord adjuster 304, so that movement of the cord
adjuster
304 may occur in more than one direction upon release of the locking mechanism
306. In one embodiment, the locking mechanism 306 is a locking tab (not
shown),
either fixed or releasable, that engages the notches or teeth 305 of the cord
adjuster
304. This locking mechanism 306 may be formed from plastic, nylon, metal or
other
light, but suitable materials. Alternatively, the locking mechanism 306 may be
configured for use with a cord adjuster 304 without notches or teeth 305, and
may be
either fixed or releasable. This mechanism 306 may be formed from plastic,
metal or
other suitable materials.
In the embodiment shown in FIG. 19, the locking mechanism 306 is provided
as part of an end cap 308 for the bottom rail 300. The end cap 308 may be
configured
so that the cord adjusters 304 pass through one or more apertures 309 in the
end cap
308. Protruding portions 307 of the cord adjusters 304 may then be trimmed
flush
with the end cap 308 once adjustment to the lift cords 302 has been made, if
desired in
some embodiments. However, configurations with the cord adjusters 304
completely
internal to the bottom rail channel 301 and/or separate from the end cap 308
are also
possible.
In operation, once the window covering is mounted in place, the lift cords 302
may be adjusted by movement of the cord adjusters 304, so as the shorten or
lengthen
the lift cords 302. Adjustment of the lift cords 302 results in leveling
adjustment of
the bottom rail 300, as desired.
As shown in FIG. 1, many fenestration products 40 include an optional interior
CA 02467548 2004-06-18
insect screen 44 that may be removably positioned over the glass panel 60 from
inside
a room or building. For fenestration products 40 that include a sliding
operator 80 of
the present invention for manipulation and control of a between-the-glass
window
covering 70, standard installation of the interior insect screen 44 would
block a user's
access to the sliding operator 80 and thus inhibit the user's control and
operation of
the window covering 70.
Referring now to FIGS. 20-24, a screen assembly 400 is shown mounted on an
interior side of glass panel 60. The screen assembly 400 includes frame 405
having
10 side members 406, head member 407 and sill member 408. Mounted within the
frame
405 is an insect screen 409. One of the side members 406 includes a screen
operator
410, including handle 411 mounted on an interior side 401 of the screen
assembly 400
for slideable movement within channel 412. A coupler 420 is also mounted for
slideable movement along coupler channel 425 on the same member 406, but on an
15 exterior side of 402 of screen assembly 400. Movement of the coupler 420 is
tied to
movement of the handle 411, such that as handle 411 is slid along channel 412,
a
drive assembly 414 produces corresponding sliding movement of the coupler 420
along coupler channel 425. In this embodiment, the handle 411 and coupler 420
are
offset from one another and driven in opposite directions from one another. As
the
20 handle 411 is slid through a full range of motion on screen assembly 400,
the coupler
420 also moves through a full range of motion.
When the screen assembly 400 is positioned against the glass panel 60, the
coupler 420 engages slide operator handle 87. As best shown in FIGS. 21 and
24,
coupler 420 includes first and second portions, 422 and 424, respectively,
between
which the handle 87 is interposed upon installation of the screen assembly
400. Thus,
movement of handle 411 along slide channel 412 correspondingly moves coupler
420
along coupler channel 425 through drive assembly 414, resulting in lift and
tilt
operation of the window blind (not shown) by movement of handle 87.
In one embodiment, as shown in FIG. 23, the drive assembly 414 includes a
drive mechanism 415, such as a cord, chain, belt, tape, or other suitable
device. The
drive mechanism 415 is preferably routed about a pulley 416 rotatable about a
shaft,
pin or other axis 417. In this embodiment, the pulley 416 is housed within a
corner
CA 02467548 2004-06-18
21
coupler 418 holding side member 406 to head member 407. A cap or cover 419 may
be included as needed to maintain the pulley 416 within the corner coupler 418
and/or
for decorative purposes. The drive mechanism 415 is preferably a continuous
loop
connected at both ends to the coupler 420.
In one embodiment, shown best in FIG. 24, a first end 426 of the drive
mechanism 415 attaches to the coupler 420 with a knot 427 or other suitable
fastening
device. A second end 428 of the drive mechanism 415 attaches to a tensioner
423
provided within the first portion 422 of the coupler 420. The tensioner 423 is
configured with a plurality of teeth 430 that engage with a plurality of
corresponding
snap ends 431 in first portion 422. The second end 428 is threaded into and
secured to
tensioner 423, which is then snapped into first portion 422 such that the
teeth 430
engage snap ends 431. Rotation of the tensioner 423 within the first portion
422,
preferably by use of screw drive slot 432, results in an adjustment to the
tension in the
drive mechanism 415 so as to maintain adequate control over movement of the
coupler 420 and, thus, the handle 87.
The present invention provides numerous advantages over other window
covering systems. The present invention includes a number of subsystems, such
as the
sliding operator, the window covering and the window covering actuation system
coupled together by a shaft passing through the glass panel for between-the-
glass
applications. These subsystems may be decoupled for ease of maintenance,
repair,
removal, cleaning, etc. The glass panel may be removed from the window sash
and
frame, with the sliding operator, the window covering actuation system and the
window covering being removed along with the panel. Any of these subsystems
may
thus be dealt with as needed.
In addition, decoupling of the sliding operator from the window covering
actuation system at the shaft allows for adjustment/readjustment of the
sliding handle
position relative to the overall window/fenestration product. In operation, a
user may
tip the window covering to disengage the shaft from the sliding operator, move
the
handle to a desired position, and then re-engage the shaft and sliding
operator. With
the gear reduction built into the sliding operator and window covering
actuation
system interface, the sliding handle may be repositioned along the length of
the
CA 02467548 2004-06-18
22
sliding channel to accommodate the user's needs. For example, in tall windows,
the
sliding operator handle may be positioned at the lower end of the channel
because the
upper end is out of reach of the average user. Alternatively, in doors, the
sliding
operator handle maybe positioned at the upper range of the channel because it
is
harder to stoop down low near the floor. For standard windows, on the other
hand, it
may be desirable to have the handle positioned in the middle of the available
range of
channel length. With the insect screen sliding operator of the present
invention, the
range of motion and position of the screen sliding handle may also be
readjusted to
match the range and position of the sliding operator on the fenestration
product.
Fenestration products with adjustable coverings, also known as window
coverings, for example those shown and described above, are commonly subjected
to
various forces that may cause problems with the lift and tilt mechanism. Such
forces
may result in the window covering becoming jammed or stuck during upward or
downward travel. In particular, the lift cord may slacken when the window
covering
encounters an obstacle or the actuation system is actuated too quickly. Slack
in the lift
cord may cause it to become disengaged with the winding mechanism and tangle
or
snarl. Attempts to rectify the situation may additionally cause damage to the
lift cords,
or other actuation system components. For window coverings mounted between
glass
window panels, jamming of the window covering and component damage cause
further problems because the window covering is not readily accessible by the
user
for readjustment and/or repair.
Referring now to FIGS. 25-27, another view of the window covering actuation
system 200 is shown, similar to that shown in FIG. 10. The system 200 includes
multiple components 203, including lift shaft 210, tilt shaft 212, gear box
220, and
clutch & brake 270. In addition, two lift spool assemblies 240 are mounted to
engage
the lift shaft 210, and two tilt drum assemblies 250 are mounted adjacent the
lift spool
assemblies 240 engaging the tilt shaft 212. The lift spool assemblies 240 each
include
the same or similar protective shroud 243 and support cradle 242.
In this embodiment, however, the lift spool 241 is replaced by a lift spool
drive system 500, including a modified lift spool 501. The modified lift spool
501
includes an exterior thread or groove 502 similar to the spiral groove 244. In
addition,
CA 02467548 2004-06-18
23
the modified lift spool 501 includes a hollow bore 503 extending throughout a
length
506 the spool 501. A plug 510 is configured to be inserted into a first end
504 of the
modified spool 501. The plug 510 has an interior center bore hole 511
extending
through it, sized to allow for free rotation of the lift shaft 210 as it
passes through the
plug 510. In addition, it includes an axially extending notch 512 configured
to allow
passage of the lift cord 92 while capturing a knot (not shown) at the end of
the lift
cord 92. This notch 512 also provides a keying function for the plug 510
relative to
the spool 501 to ensure angular alignment of the plug 510. In one embodiment,
the
plug 510 is formed from a polymer, such as an equivalent material to that used
for the
modified lift spool 501; however, other suitable materials may also be used,
as would
be known by one skilled in the art.
At a second end 505, the modified spool 501 includes an edge notch 50?
configured to mate with a spool stop 516 on a nut 515. The spool stop 516
extends
radially from the nut surface, as well as axially from a leading edge 519 of
the nut
515. A slightly undercut flat region 518 is formed adjacent the spool stop
516. The
nut 515 is received within and adhered to the bore 503, such that it is
generally flush
with the second end 505, except for the spool stop 516. An interior threaded
bore 51?
extends through the nut 515, with the interior threads configured to mesh with
exterior
threads 521 on a drive rod 520. The nut 515 and drive rod 520 are preferably
formed
from brass or other suitable materials, including but not limited to plastic
or zinc die
cast construction.
The rod threads 521 extend along a majority of a rod length 522, except for an
end region 523. In one embodiment, this end region 523 is preferably knurled,
however, a smooth end region 523 may alternatively be provided. The drive rod
520
has an interior bore 524 extending the length 522 of the rod 520. At least a
portion of
the bore 524 is configured to mate with the lift shaft 210, so that rotation
of the lift
shaft 210 results in rotation of the rod 520 in either direction. In this
embodiment, the
bore 524 is generally square in cross-section to accommodate the generally
square lift
shaft 210, at least in the area of the end region 523.
A stop collar 525 is fitted about the end region 523 of the drive rod 520 by
insertion of the end region 523 into an interior through-bore 526 of the stop
collar
CA 02467548 2004-06-18
24
525. The stop collar 525 is prevented from rotating due to attachment to the
rod 520,
such as by a press-fit between the collar 525 and end region 523, adhesive or
by other
suitable methods. A knurled end region 523 aids in securing the stop collar
525 to the
rod 520. The stop collar 525 includes a drive stop 527 that extends radially
from the
outer collar surface, as well as axially from a back edge 529 of the collar
525. A
slightly undercut flat region 528 is formed adjacent the drive stop 52?. The
stop collar
525 is also preferably formed from brass, or from another suitable material.
The drive rod 520 threads into and out of the modified spool 501 upon rotation
of the lift shaft 210. In this embodiment, inward movement is caused by
clockwise
rotation and outward movement is caused by counter-clockwise rotation;
however,
reversed threads are also possible. Near the clockwise/inward rotational limit
of the
drive rod 520 into the spool 501, the drive stop 527 of the stop collar 525
encounters
the spool stop 516 as the spool stop 516 passes over the flat region 528 on
stop collar
525. Rotation of the drive rod 520 relative to the spool 501 then ends, and
continuing
rotation of the lift shaft 210 in the clockwise direction results in generally
simultaneous rotation of both the drive rod 520 and the spool 501.
A reversal in the direction of rotation of the lift shaft 210, that is a
change to a
counter-clockwise direction in this embodiment, causes a disengagement of the
spool
stop 516 and drive stop 527. As a result, the lift shaft 210 and drive rod 520
freely
rotate with respect to the spool 501, such that the spool 502 is not driven by
the lift
shaft 210 in a counter-clockwise direction. Another change in rotational
direction and
movement of the drive rod 520 back to its limit, such that the drive stop 527
and spool
stop 516 engage, are required before the lift shaft 210 again drives the
spool's rotation.
In operation, the drive rod 520 is preferably at its inward most position with
respect to the modified spool 501, such that the drive stop 527 and spool stop
516 are
engaged. As the window covering 90 is lifted or opened, the lift shaft 210
rotates
clockwise, also rotating the drive rod 520 and modified lift spool 501 causing
the lift
cord 92 to be wound up about the thread or groove 502 under the shroud 243. As
the
window covering 90 is lowered or closed, the lift shaft 210 rotates counter-
clockwise,
releasing the clutch/brake 270 and allowing the window covering 90 to drop
under its
own weight. As a result, the lift cord 92 unwinds from the modified lift spool
501
CA 02467548 2004-06-18
causing it to rotate counter-clockwise in conjunction with the rotation of the
lift shaft
210. Therefore, the drive rod 520 rotates along with the spool 501 and the
drive stop
527 and spool stop 516 remain engaged.
5 During lowering of the window covering 90, the window covering 90 may
encounter an obstruction, such as a loose muntin bar or other object, or the
window
covering 90 may be operated too quickly, such that slack is formed in the lift
cords
92. In other embodiments of the window covering actuation system 200, the
continuing movement of the operator causes the lift shaft 210 to continue
rotating and
10 the lift spool 241 to also continue rotating. As a result, the lift cords
92 wound around
the lift spools 241 get snarled, tangled, jammed and/or otherwise messed up,
which
may cause permanent damage to the cords or the system. In this embodiment,
however, once slack is encountered in the lift cords 92, the modified lift
spool 501
stops rotating, but the lift shaft 210 continues to rotate along with the
drive rod 520.
15 The drive rod 520 unscrews from the modified lift spool 501 as long as the
lift shaft
210 continues to rotate in that direction due to continued operation of the
window
covering operator. The drive rod 520, as shown in this embodiment, is
configured
with fine enough threads so that, should a problem be encountered at the top
most
position of the window covering 90, there are sufficient threads to allow fox
complete
20 operation of the window covering operator to its lowermost limit on smaller
fenestration products or up to five feet (1.52 meters) of travel on larger
units. More
threads may be provided for larger fenestration products, as desired.
Once the obstruction is cleared or the problem is otherwise resolved,
operation
25 of the window covering 90 may proceed. As stated above, reversal of
direction of the
operator results in reversed rotation of the lift shaft 210, along with the
drive rod 520.
The modified spool 501 does not start rotating until the drive rod 520 reaches
its
inward limit and the drive stop 527 engages the spool stop 516. As a result,
the
angular orientation of the modified spool 501 remains in sync with the other
lift
spools 501 within the overall actuation system 200, and thus rotation
registration
between the separate lift spool assemblies 240 is maintained. Therefore,
misalignment
of the window covering 90 is avoided.
In this embodiment, one way drive of the modified spool 501 is provided by
CA 02467548 2004-06-18
26
the nut 515 and spool stop 516 working in conjunction with stop collar 525 and
drive
stop 527. However, it is to be understood that other mechanisms for limiting
rotational movement of the drive rod 520 in one direction may also be
provided. One
alternative embodiment includes configuration of the mechanism with left hand
threads for rotation in an opposite direction from the mechanism set forth
above.
Other embodiments of the mechanism include, but are not limited to,
construction of
the spool 501, nut 515 and spool stop 516 as one integral unit or single part,
and/or
the construction of the drive rod 520, stop collar 525 and drive stop 527 as
one
integral unit or single part. These types of parts may be molded and/or
machined.
Variations of this same concept are also possible. In addition, other
embodiments, in
which the spool 501 and drive rod 520 interconnect for coordinated rotation in
one
direction, yet are separate for independent rotation in an opposite direction,
are within
the skill of those in the art and are covered by this invention.
The lift spool drive assembly of the present invention provides the benefit of
resolving a problem frequently encountered with window covering operation,
while
fitting within the confines of the current actuation system. In particular, in
actuation
systems provided for between-the-glass window coverings, the available
envelope of
space for the components of the actuation system is very limited. Therefore,
the
provision of a mechanism for resolving this problem is most useful and
efficient if it
is confined to the provided space and does not extend beyond the existing
actuation
components. In addition, when used with between-the-glass window coverings
having
the sliding operator, as described above, the tilt function of the window
covering may
be operated without raising or lowering the covering at its lower limit of
travel. When
the window covering reaches its lower limit, continuing movement of the
sliding
operator results in disengagement of the drive screws from the lift spools and
permits
the operator handle to travel in either direction without raising or lowering
the shade.
Although generally described with respect to between-the-glass window
covering products, use of the present invention is not limited to between-the-
glass
window coverings units, but may used and benefit other type of window covering
configurations. For example, the overall height tolerance of a window covering
is
much greater when the present invention drive system is used, since there is
no
negative consequence to continued operator handle movement after the window
CA 02467548 2004-06-18
27
covering reaches the lower limit of the glass. This improves the
manufacturability of
the window covering and/or fenestration product because the window covering
length
becomes less critical and could be made a little longer than conventionally
would be
provided to account for variables in the manufacturing process, such as the
uncertain
effective spring constant of pleated shade material, for example.
All of the patents and patent applications disclosed herein, including those
set
forth in the Background of the Invention, are hereby incorporated by
reference.
Although the present invention has been described with reference to preferred
embodiments, workers skilled in the art will recognize that changes may be
made in
form and detail without departing from the spirit and scope of the invention.
In
addition, the invention is not to be taken as limited to all of the details
thereof as
modifications and variations thereof may be made without departing from the
spirit or
scope of the invention. Thus, the scope of the present invention should not be
limited
to the structures described in this application, but only by the structures
described by
the language of the claims and the equivalents of those structures.
