Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates to a bidirectional rotation device
and more particularly relates to an electromechanical bidirec-
tional rotation device applicable for controlling a variety of
mechanical apparatuses.
In electromechanical control apparatuses, it is often
required to control a mechanical componet such as a baffle,
interlock or the like between two positions selectively and
alternately. For example, in the conduction of a gaseoous
material from one location to another location, a baffle plate
is provided in the conducting pipe so that the baffle can be
pivotted to position either parallel to the longitudinal axis
of the pipe to allow the gas to flow through the pipe or
transverse to the longitudinal axis thus blocking the flow of
gas through the pipe. An electromechanical system is commonly
employed to provide the positioning of such baffle. The baffle
is connected to a mechanical pivotting linkage outside of the
pipe, and the linkage is coupled to an electromagnetic solen-
oid. The solenoid can be energized to push the linkage in a
direction to position the baffle at the selec-ted position
accordingly. In such system, a biassing means such as a bias-
sing spring must be provided to return the baEfle to the first
poSLtion when the solenoid is de-energized. It can be appreci-
ated that the solenoid must be of such size that sufficiency
strength is generated therein to overcome the force of the
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25 ~ blassing spring initially in order to pivot the baffle to the
selected blocking position. Furthermore, in order to maintain
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the baffle in the blocking position, the solenoid must remain
energiz~ed. Thus, it is not energy efficient to operate such
system. Moreover, such solenold system requires a relatively
high voltag~ to operate. Therefore, it is not suitable for
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use, particularly, in a low voltage system. For a low voltage
system, complex electrical control is usually required to
provide sufficient torque to operate the mechanical component.
Also, in such electromechanical arrangement, the mechanical
linka~e is oEten subject to breakdown after a relatively short
period of time in use.
It is a principal object of the present invention to
provide an electromechanical bidirectional rotation device
which has relatively no mechanical wearing parts.
It is another object of the present invention to provide
an electromechanical rotation device suitable for use in a low
voltage system.
It is another object of the present invention to provide
a baffling system for a gas conducting pipe having a high
torque electromechanica] control device for the baffle.
It is yet another object of the present invention to
provide an electromechanical device which has low energy
comsumption.
It is still another object of the present invention to
provide an electromechanical device which has relatively not
wearing parts and is simple in construction and can be incor-
porated in other control system easily.
Other objects of this Lnvention will appear in the
~ following description and appended claims, reference being
made to the accompanying draw:ings forming a part of the
specification, in which
Figure 1 is a schematic diagram of the electromechani-
cal device according to the present invention.
Figure 2 is a partial sectional elevation of the electro-
mechanical baffle device for a gas conducting pipe according
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to the present invention.
Figure 3 is a top sectional elevation view along section
line III - III of Figure 2.
I'he present invention is illustrated in the accompanying
figures wherein similar parts are indicated by the same
reference numerals throughout the several views, and where
pairs or parts are used the parts are referenced by prime of
reference numeral.
In the drawings, the direct current ( DC ) motor 10 in
the device of the present invention may be of a permanent
magnet or electromagnetic type which is operative to rotate in
one direction when the direct current voltage is applied to
it in one polarity, and to rotate in a reverse direction when
the voltage of a reverse polarity is applied thereto. A
capacitor 11 is connected in series with the DC motor 10. The
combination of the series-connected DC motor 10 and capacitor
11 is connected to a reversible switching means 12. The
reversible switching means 12 may be a mechanical switch or an
electronic switch of the same function. It may be a single
pole double throw switch or double pole double throw switch
having connection terminals 13 and 14, and supply terminal 15
and 16. The connection terminal 13 is connected to the posi-
tive terminal of the DC motor 10 through the capacitor 11 as
shown, and the connection terminal 14 is connected to the
negative terminal of the DC motor 10. The supply terminal 15
is connected to the positive polarity of a direct current
voltage source 17 while the supply terminal 16 is connected to
the negative polarity of the supply voltage source 17. In the
case of a s1ngle pole double throw switch, the reversible
switching means 12 has one single movable contact therein
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coupled to the connection terminal 13. The movable contact is
operative to one position at which it connects the the connec-
tion terminal 13 to the supply terminal 15, and to a second
position wherein the movable contact connects the connection
termina] 13 to the connection terminal 14. Supply terminal 16
and connection terminal 14 are commonly connected together.
When the movable contact of the reversible switching means is
at the first postion the positive potential flows from the
voltage source 17 through capacitor 11 to the motor 10, and
the combination of capacitor 11 and motor 10 will act as a
common capacitor-inductor circuit, so that the capacitor 11
will be charged to the positive potential as shown in Figure
l. The charged capacitor 11 will then cause the motor 10 to
rotate in one direction for a predetermined period of time
until the charges in the capacitor 11 are expended. As soon as
it is discharged, the capacitor 11 will again be charged by
the voltage source 17 to the same potential. If at this time,
the reversible switching means 12 is operated to the second
position with the connection terminal 13 connected to the
connection 14, the charges in the already fully charged
capacitor l1 will then be applied in the reversed polarities
to the motor 10, thus causing the motor 10 to rotate in the
reversed direction for a short period of time until the
~ .
~ capacitor 11 is completely discharged. If the reversible
:
switch1ng means 12 is then again operated to return to its
first position, the original condition will prevail and the
; motor 10 will rotate again in the first direction as described
above. In this manner, the motor lO can be actuated to rotate
in the opposite directions alternately.
In the case the reversible switching means 12 is a double
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2 ~
throw double pole sw:itch~ it is operative selectively in one
position in which the positive polarity of the voltage source
17 is applied to the positive terminal of the DC motor 10
through the capacitor 11 while the negative polarity of the
voltage source 17 is connected through the supply terminal 16
and connection terminal 1~ to the negative terminal of the DC
motor 10; and in the second position, the negative polarity of
the voltage source 17 is applied to the positive terminal of
the DC motor 10 through the capacitor 11 while the positive
polarity of the voltage source 17 is connected to the negative
terminal of the DC motor 10. It can be appreciated by those
skilled in the art that the capacitor 11 may be connected in
series with the DC motor lO on either the positive terminal
side of the DC motor 10 as shown or at the negative terminal
side therein. Also, the negative and positive terminals may be
opposite to those shown in Figure 1. Thus, the difference
between the use of a single pole double throw switch and a
double pole double throw switch is that in the first case the
capacitor 11 will be charged at only one position of the
reversible switching means, whereas it will be charged in both
positions of the reversible switching means.
The electromechanical device of the present invention may
be employed to provide the control of a varieties of mechani-
cal components that require to be positioned in two alternate
positions selectively. For example, the device may be incor-
porated in a gas conducting system having a baffle 18 rotat-
ably located within a pipe 19 which is used to conduct a
gaseous material or air flow 20 therethrough. The baffle 18 is
mounted on a rotatable shaft 21 coupled to -the rotary shaft 22
of the DC motor 10 as described above. The baffle 18 will
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rotate in one direction when the reversible switching means 12
is operated in one condition and it will rotate in the reverse
d:irection when the reversible switching means 12 is operated
in the second condition a].ternately and sequentially. When the
baffle 18 is rotated in one direction i.t will be located in a
position abutt:ing the abutment pin 21 located in the inside
surface of the pipe 19 such that the plane of the baff].e 18 i9
parallel to the longitudinal axis of the pipe 19, thus allow-
ing the gas to flow through the pipe 19. When the baffle 18 is
rotated in the reverse direction by the operation of the
reversible sw:itching means 12 it will rotate in the reverse
direction until it is maintained in the position transverse or
perpendicular to the longitudinal axis of the pipe 19 by the
shoulder pin 24. Thus, the baffle 18 blocks the pipe 19 to
prevent the gas from flowing therethrough.
The magnitude of the torque applied to the baffle 18 as
well as the period of its rotation are dependent upon the
value of the capacitor 11. The larger the capacitance of the
capacitor 11, the larger will be the torque and longer will be
the rotation of the DC motor 10 maintained by the capacitor
11. Furthermore, due to the relatively high torque that can be
developed by the present device with a low voltage direct
current motor, the device lends itself for incorporation in a
low voltage electrical system used for controlling the operat-
i.on of mechanical components in which the mechanical operation
of such components requires a relatively high torque.
While I have illustrated in the drawings and description
above specific methods and apparatus constituting preferred
embodiments of the invention, it will be appreciated that
various modifications may be made in the form of the apparat-
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us, and that equ:ivalent methods, elements and mechanism may be
substituted therefor without departing from the scope of the
invention. All such changes, including reversals of parts and
the use of certain features of the invention independently of
other features, all fall within the spirit and scope oE the
invention as defined in the appended claims.
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