U.S. patent application number 11/545183 was filed with the patent office on 2007-02-08 for actuator assembly.
Invention is credited to Sidney Edward Fisher.
Application Number | 20070029714 11/545183 |
Document ID | / |
Family ID | 29595554 |
Filed Date | 2007-02-08 |
United States Patent
Application |
20070029714 |
Kind Code |
A1 |
Fisher; Sidney Edward |
February 8, 2007 |
Actuator assembly
Abstract
An actuator assembly includes an actuator, an output member, and
a spring arrangement having at least one spiral return spring. The
output member has a neutral position, a first actuated position,
and a second actuated position. The neutral position is between the
first actuated position and the second actuated position. The
output member capable of being driven by the actuator from the
neutral position to the first actuated position and to the second
actuated position. The spring arrangement is arranged to bias the
output member towards the neutral position from the first actuated
position and is arranged to bias the output member towards the
neutral position from the second actuated position.
Inventors: |
Fisher; Sidney Edward;
(Redditch, GB) |
Correspondence
Address: |
CARLSON, GASKEY & OLDS, P.C.
400 WEST MAPLE ROAD
SUITE 350
BIRMINGHAM
MI
48009
US
|
Family ID: |
29595554 |
Appl. No.: |
11/545183 |
Filed: |
October 10, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10970694 |
Oct 21, 2004 |
7128191 |
|
|
11545183 |
Oct 10, 2006 |
|
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Current U.S.
Class: |
267/155 |
Current CPC
Class: |
E05B 81/50 20130101;
Y10T 74/19633 20150115; E05B 81/25 20130101; F16F 1/10 20130101;
Y10T 74/19828 20150115; E05B 2015/042 20130101 |
Class at
Publication: |
267/155 |
International
Class: |
F16F 1/06 20060101
F16F001/06 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 22, 2003 |
GB |
0324576.8 |
Claims
1. A combined spring comprising: a first spiral return spring and a
second spiral return spring, wherein the first spiral return spring
and the second spiral return spring are integral, the first spiral
return spring is wound in a first direction, the second spiral
return spring is wound in a second direction opposite to the first
direction, and the first spiral return spring and the second spiral
return spring are joined at a common arm.
2. The combined spring according to claim 1 wherein the first
spiral return spring and the second spiral return spring are
concentric.
3. The combined spring according to claim 1 wherein the first
spiral return spring defines a first plane, the second spiral
return spring defines a second plane, and the first plane and the
second plane are spaced apart relative to each other.
4. (canceled)
5. The combined spring according to claim 1 wherein the common arm
is oriented in a radial direction.
6. The combined spring according to claim 1 wherein the first
spiral return spring includes a first free end and the second
spiral return spring includes a second free end, rotation of the
first free end relative to the common arm in the first direction
provides a return force in the second direction, and rotation of
the second free end relative to the common arm in the second
direction provides a return force in the first direction.
7. The combined spring according to claim 1 wherein the first
spiral return spring includes a first free end and the second
spiral return spring includes a second free end, and the common arm
is configured to be mounted such that rotation of the first free
end does not cause rotation of the second free end, and rotation of
the second free end does not cause rotation of the first free
end.
8. A method of manufacturing a combined spring, the method
comprising the steps of: creating a blank to form a first spring
portion, a second spring portion, and a common inner arm; winding
the first spring portion in a first direction about the common
inner arm; and winding the second spring portion in a second
direction about the common inner arm, wherein the second direction
is opposite to the first direction.
9. The method according to claim 8 wherein the step of creating the
blank includes cutting a slot in the blank to create the first
spring portion, the second spring portion, and the common inner
arm.
10. The method according to claim 8 including the steps of creating
a hole at a point on the blank corresponding to an edge of the
common inner arm and shearing the blank along a line from an outer
edge of the blank to the hole.
11. The method according to claim 10 including the step of
deforming at least one of the first spring portion and the second
spring portion to separate the first spring portion and the second
spring portion.
12. The method according to claim 8 wherein the step of creating
the blank creates a substantially `S` shape blank.
13. The method according to claim 8 wherein the step of creating
the blank creates a substantially rectangular shape blank.
14. An actuator assembly comprising: an actuator; an output member
having a neutral position, a first actuated position, and a second
actuated position, wherein the neutral position is located between
the first actuated position and the second actuated position, and
the output member is drivable by the actuator from the neutral
position to the first actuated position and to the second actuated
position; and a combined spring arranged to bias the output member
towards the neutral position from the first actuated position and
arranged to bias the output member towards the neutral position
from the second actuated position, wherein the combined spring
includes a first spiral return spring and a second spiral return
spring, and the first spiral return spring and the second spiral
return spring are integral, and wherein the first spiral return
spring is wound in a first direction and the second spiral return
spring is wound in a second direction that is opposite to the first
direction.
Description
REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional application of U.S. Ser.
No. 10/970,694, which was filed on Oct. 21, 2004, which claims
priority to United Kingdom Patent Application GB 0324576.8 filed on
Oct. 22, 2003.
BACKGROUND OF THE INVENTION
[0002] The present invention relates generally to actuator
assemblies, and more particularly to actuator assemblies for use
with latches in vehicle doors and other closures.
[0003] A known vehicle door latch actuator assembly includes an
actuator in the form of an electric motor that moves components of
a latch from a neutral position to a locked position and an
unlocked position.
[0004] After the electric motor has moved the latch to the locked
position or the unlocked position, the electric motor is powered in
the opposite direction to return to the neutral position. When the
latch is manually locked or unlocked by, for example, using a key
or a sill button, it is not necessary to manually drive the
electric motor back to the neutral position, reducing the effort
required.
[0005] Known vehicle door latch actuator assemblies include a
return mechanism employing a helical spring, as shown in European
Patent Application EP0267423.
[0006] As the electric motor drives in one direction, one end of
the helical spring rotates about a longitudinal axis relative to
the other end, leaving the helical spring in a torsionally loaded
state. When power to the electric motor stops, the helical spring
torsionally unwinds to bias the electric motor back towards the
neutral position. Therefore, the electric motor does not need to be
driven in the opposite direction.
[0007] In its simplest form, a helical spring is a spring that is
formed by winding wire into a helix along a curved outer surface of
an imaginary cylinder. A base of the imaginary cylinder forms a
radial plane that, at one end of the spring, lies at 90 degrees to
the central elongate (longitudinal) axis of the spring. A coil of
the spring is a loop of wire that completes a 360 degree
circumnavigation of the imaginary cylinder, and no two points along
any given coil exist in any single plane that lies parallel to the
radial plane. FIG. 14 of U.S. Pat. No. 4,779,912 shows an example
of a helical spring. The elongate axis may also be curved, i.e.,
where the spring is wound on part of an imaginary torus rather than
being wound on an imaginary cylinder.
[0008] Further, helical springs are to be distinguished from
conical springs, which are distinct from helical springs in that
they are formed by winding wire into a helix along the outer curved
surface of a cone. FIG. 3 of U.S. Pat. No. 4,821,521 shows an
example of a conical spring. Typically, helical and conical springs
are used to provide either a compressive force or a tensile force,
in other words, to act in an axial manner. However, it is also
possible to employ each of these types of spring to provide a
torsional bias.
[0009] It will be appreciated that helical springs and conical
springs are distinct from spiral springs, which will be described
in further detail shortly.
[0010] A problem with known return mechanisms including helical
springs is that, when loaded, there is a tendency for the stress to
concentrate in one area of the helical spring, thereby reducing the
fatigue life and possibly resulting in the failure of the return
mechanism.
[0011] The present invention provides an actuator assembly with an
increased fatigue life.
SUMMARY OF INVENTION
[0012] According to one embodiment of the present invention, an
actuator assembly includes an actuator, an output member, and a
spring arrangement having at least one spiral return spring. The
output member has a neutral position, a first actuated position,
and a second actuated position. The neutral position is between the
first actuated position and the second actuated position. Further,
the output member is capable of being driven by the actuator from
the neutral position to the first actuated position and to the
second actuated position. The spring arrangement is arranged to
bias the output member towards the neutral position from the first
actuated position and to bias the output member towards the neutral
position from the second actuated position.
[0013] According to another embodiment of the present invention, an
output member subassembly includes an output member and a spring
arrangement having at least one spiral return spring. The output
member has a neutral position, a first actuated position, and a
second actuated position. The neutral position is between the first
actuated position and the second actuated position. Further, the
output member is capable of being driven by an actuator from the
neutral position to the first actuated position and to the second
actuated position. The spring arrangement is arranged to bias the
output member towards the neutral position from the first actuated
position and to bias the output member towards the neutral position
from the second actuated position.
[0014] A spiral spring can be a conical spring that has been
compressed in the axial direction so that the coils lie within each
other. In other words, the spiral spring is a spring formed by
winding a strip of metal initially onto a cylinder, and successive
coils are laid onto the previous coil. Because all of the coils lie
in the same plane, the spring can only provide a relatively small
amount of axial bias. Therefore, the purpose of the spiral spring
is to provide a torsional resistance, rather than an axial
resistance, offered by either a helical spring or a conical
spring.
[0015] By using a spiral return spring rather than a helical return
spring, the stress associated with winding and unwinding the spiral
return spring is more evenly distributed through the spring,
increasing fatigue life.
[0016] According to yet another embodiment of the present
invention, a method of assembling an actuator assembly includes the
steps of providing an actuator, an output member, a spring
arrangement and a chassis. The method further includes the steps of
assembling the spring arrangement onto the output member to provide
an output member subassembly, assembling the output member
subassembly onto the chassis such that the spring arrangement is in
the neutral position, and assembling the actuator onto the
chassis.
[0017] Because the spring arrangement is mounted on the output
member to provide a subassembly prior to mounting the subsequently
onto the chassis, the potentially complex stage of locating the
spring arrangement can be conducted remotely from the chassis, thus
increasing the efficiency of the assembly process.
[0018] According to yet another embodiment of the present
invention, a combined spring includes a first spiral return spring
and a second spiral return spring that is integral with the first
spiral return spring. The first spiral return spring of the
combined spring is wound in a first direction, and the second
spiral return spring of the combined spring is wound in a second
direction opposite to the first direction.
[0019] These and other features of the present invention will be
best understood from the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The invention will now be described by way of example with
reference to the accompanying drawings, in which:
[0021] FIG. 1 is a plan view of an actuator assembly according to a
first embodiment of the present invention;
[0022] FIG. 2 is an exploded perspective view of part of the
actuator assembly illustrated in FIG. 1 in a neutral position;
[0023] FIG. 3 is a plan view of part of the actuator assembly
illustrated in FIG. 1 after assembly;
[0024] FIG. 4 is an exploded perspective view of part of an
actuator assembly according to a second embodiment of the present
invention in a neutral position;
[0025] FIG. 5 is a plan view of part of the actuator assembly
illustrated in FIG. 4 after assembly;
[0026] FIG. 6 is an exploded perspective view of a first spiral
return spring and a second spiral return spring of an actuator
assembly according to a third embodiment of the present invention
in a free state;
[0027] FIG. 7 is an exploded perspective view of part of the
actuator assembly illustrated in FIG. 6 in a neutral position;
[0028] FIG. 8 is an exploded perspective view of part of the
actuator assembly illustrated in FIG. 6 after actuation to a first
actuated position;
[0029] FIG. 9 is an exploded perspective view of part an actuator
assembly according to a fourth embodiment of the present invention
in a neutral position;
[0030] FIG. 10 is a plan view of part of the actuator assembly
illustrated in FIG. 9 after assembly;
[0031] FIG. 11 is an exploded perspective view of part of an
actuator assembly according to a fifth embodiment of the present
invention in a neutral position;
[0032] FIG. 12 is a plan view of part of the actuator assembly
illustrated in FIG. 11 after assembly;
[0033] FIG. 13 is an exploded perspective view of part of an
actuator assembly according to a sixth embodiment of the present
invention in a neutral position;
[0034] FIG. 14 is a plan view of part of the actuator assembly
illustrated in FIG. 13 after assembly;
[0035] FIG. 15 is an exploded perspective view of a first spiral
return spring and a second spiral return spring of an actuator
assembly according to a seventh embodiment of the present invention
in a free state;
[0036] FIG. 16 is an exploded perspective view of part of the
actuator assembly illustrated in FIG. 15 in a neutral position;
[0037] FIG. 17 is an exploded perspective view of part of the
actuator assembly illustrated in FIG. 15 after actuation to a first
actuated position;
[0038] FIG. 18A is a plan view of the first spiral return spring
and the second spiral return spring of the actuator assembly
illustrated in FIG. 15 in their free state;
[0039] FIG. 18B is a plan view of part of the actuator assembly
illustrated in FIG. 15 in a neutral position;
[0040] FIG. 18C is a plan view of part of the actuator assembly
illustrated in FIG. 15 after actuation to a first actuated
position;
[0041] FIG. 19 is an exploded perspective upper view of part of an
actuator assembly according to an eight embodiment of the present
invention in a neutral position;
[0042] FIG. 20 is an exploded perspective lower view of the part of
the actuator assembly illustrated in FIG. 19 in a neutral
position;
[0043] FIG. 21 is a plan view of the actuator assembly illustrated
in FIG. 19 in a neutral position;
[0044] FIG. 22 is an exploded perspective view of part of an
actuator assembly according to a ninth embodiment of the present
invention in a neutral position;
[0045] FIG. 23 is an alternative exploded perspective view of the
components illustrated in FIG. 22;
[0046] FIG. 24A is an enlarged developed view of a combined spring
of the actuator assembly illustrated in FIG. 22;
[0047] FIG. 24B is an enlarged developed view of an alternative
combined spring;
[0048] FIG. 24C is an enlarged developed view of another
alternative combined spring;
[0049] FIG. 25 is a plan view of part of the actuator assembly
illustrated in FIG. 22 in a neutral position; and
[0050] FIG. 26 is a schematic view of a latch assembly including an
actuator assembly according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0051] As illustrated in FIG. 1, an actuator assembly 10 includes
an actuator in the form of an electric motor 12, a chassis 14, an
output member in the form of a gear wheel 16, and a spiral return
spring 18 (shown hidden in FIG. 1).
[0052] A spiral spring is a spring that is wound in substantially
one plane and has coils of decreasing diameter, as opposed to a
helical spring that has coils of a constant diameter extending in
another plane. Typically, a spiral spring is wound from wire having
a substantially rectangular cross-sectional profile, and a helical
spring is wound from wire having a substantially round
cross-sectional profile.
[0053] The gear wheel 16 is rotationally mounted on the chassis 14
at a pivot pin 20 and includes an output in the form of a pin 22
mounted thereon that is connected to a linkage 25. The linkage 25
is connected to a device (not shown in FIG. 1) that requires
actuation.
[0054] The electric motor 12 is drivingly connected to the gear
wheel 16 by a worm gear 17. The worm gear 17 is mounted
rotationally fast on an electric motor shaft 15 and engages the
gear wheel 16 via gear teeth (not shown). The electric motor shaft
15 and the worm gear 17 form a transmission path between the
electric motor 12 and the gear wheel 16 such that actuation of the
electric motor 12 causes the gear wheel 16 to rotate about the
pivot pin 20.
[0055] FIG. 2 shows components of part of the actuator assembly 10
in more detail. The actuator assembly 10 further includes a round
spigot 24 mounted on and integral with the chassis 14, i.e.,
rotationally fast with the chassis 14. The round spigot 24 includes
a through hole 26 and a spigot slot 28 extending from its periphery
towards the through hole 26. The pivot pin 20 extends through the
through hole 26 of the round spigot 24 and is mounted on and is
rotationally fast with the chassis 14.
[0056] The gear wheel 16 has an outer wall 30 that defines a recess
32, and the recess 32 includes a hole 38. The outer wall 30
includes a portion 34 having a thickness greater than the thickness
of the remainder of the outer wall 30, and the portion 34 includes
a drive slot 36.
[0057] The spiral return spring 18 has an outer arm 40 and an inner
arm 42. The spiral return spring 18 in shown in a free state, and
the inner arm 42 and the outer arm 40 are substantially
aligned.
[0058] FIG. 3 shows the actuator assembly 10 after it has been
assembled. First, the spiral return spring 18 is assembled onto the
gear wheel 16, and the outer arm 40 of the spiral return spring 18
is located in the drive slot 36. The gear wheel 16 is then mounted
on the chassis 14 by mounting the gear wheel 16 and the spiral
return spring 18 onto the round spigot 24 and the pivot pin 20 so
that the hole 38 is mounted on the pivot pin 20, at the same time
locating the inner arm 42 of the spiral return spring 18 in the
spigot slot 28.
[0059] The actuator assembly 10 is shown in a neutral position. The
inner arms 42 and the outer arms 40 of the spiral return spring 18
are still in alignment, and thus the spiral return spring 18 is
still in its free state once it is assembled onto the chassis 14,
i.e., the spiral return spring 18 is not pre-tensioned. Thus, the
actuator assembly 10 has no pre-tensioning.
[0060] Operation of the actuator assembly 10 is as follows. FIG. 3
shows the actuator assembly 10 in a neutral position A. When
actuation is required, an electrical current is supplied to the
electric motor 12, rotating the gear wheel 16 in a first direction
(clockwise when viewing FIG. 3) about the pivot pin 20 towards a
first actuated position B. Typically, the neutral position A and
the first actuated position B are separated by approximately 120
degrees. As the gear wheel 16 rotates in the first direction, the
outer arm 40 of the spiral return spring 18 moves because it is
located in the drive slot 36 of the gear wheel 16. The inner arm 42
of the spiral return spring 18 is located in the spigot slot 28,
and therefore the inner arm 42 does not move (because the round
spigot 24 is mounted on the chassis 14). As the gear wheel 16
rotates in the first direction, the spiral return spring 18 winds
up as the outer arm 40 moves towards the inner arm 42.
[0061] Once the gear wheel 16 has been actuated to the first
actuated position B, power to the electric motor 12 is stopped.
This can be achieved, for example, by powering the electric motor
12 only for a predetermined period of time and including a stop
feature (not shown) on the actuator assembly 10, by activating a
switch (not shown) which cuts the power, or by using a stepper
motor.
[0062] With the gear wheel 16 in the first actuated position B, the
outer arm 40 of the spiral return spring 18 acts upon the drive
slot 36 to bias the gear wheel 16 back towards the neutral position
A. The gear wheel 16 will remain in the neutral position B until
the gear wheel 16 is actuated again. After actuation to the first
actuated position B, the gear wheel 16 is biased towards the
neutral position A by the spiral return spring 18.
[0063] The electric motor 12 can also drive the gear wheel 16 in a
second direction (counter-clockwise when viewing FIG. 3) towards a
second actuated position C. Operation of the actuator assembly 10
in the second direction is identical to that in the first
direction, except the spiral return spring 18 is unwound when being
driven in the second direction by the electric motor 12.
Nevertheless, the gear wheel 16 is still biased towards the neutral
position A when the gear wheel 16 is at the second actuated
position C. It can also be seen from FIG. 3 that the neutral
position A lies between the first actuated position B and the
second actuated position C.
[0064] Further, rotation of the gear wheel 16 in either the first
or second direction causes the linkage 25 to move and the device
(not shown) to which it is connected to move.
[0065] FIGS. 4 and 5 illustrate part of the actuator assembly 110
according to a second embodiment of the present invention with
features identical or similar to the actuator assembly 10 numbered
100 greater.
[0066] The second embodiment includes two spiral return springs 150
and 152 as opposed to the one spiral return spring 18 of the first
embodiment.
[0067] The actuator assembly 110 includes a first spiral return
spring 152 having an outer arm 154 and an inner arm 156 and a
second spiral return spring 150 having an outer arm 140 and an
inner arm 142. The first spiral return spring 152 and the second
spiral return spring 150 are identical (though one is mounted
upside down relative to the other). The first spiral return spring
152 has an upper surface 155 and the second spiral return spring
150 has a lower surface 157. The first spiral return spring 152 and
the second spiral return spring 150 are shown in a free state.
[0068] The actuator assembly 110 further includes a stop 158
mounted on and integral with a chassis 114. The stop has a first
end 159 and a second end 161.
[0069] A gear wheel 116 includes a drive formation 160 mounted
within a recess 132. The drive formation 160 has a first end 162
and a second end 164.
[0070] FIG. 5 shows the actuator assembly 110 after it has been
assembled as follows. The first spiral return spring 152 and the
second spiral return spring 150 are assembled onto the chassis 114
such that the outer arm 154 of the first spiral return spring 152
abuts the second end 161 of the stop 158, and the outer arm 140 of
the second spiral return spring 150 abuts the first end 159 of the
stop 158. The inner arm 156 of the first spiral return spring 152
and the inner arm 142 of the second spiral return spring 150 locate
in the spigot slot 128 of a spigot 124. While the first spiral
return spring 152 and second spiral return spring 150 are
identical, they are assembled onto the chassis 114 such that they
are wound in opposite directions relative to each other by simply
turning one of them upside down.
[0071] The gear wheel 116 is then positioned on a pivot pin 120
such that the outer arm 154 of the first spiral return spring 152
abuts the second end 164 of the drive formation 160, and the outer
arm 140 of the second spiral return spring 150 abuts the first end
162 of the drive formation 160.
[0072] As illustrated in FIG. 5, the actuator assembly 110 is in a
neutral position A. As with the actuator assembly 10, the inner
arms 142 and 156 and the outer arms 140 and 154 of the spiral
return springs 150 and 152 are still in their same relative
positions. Thus, the spiral return springs 150 and 152,
respectively, are still in their free state once assembled onto the
chassis 114, i.e., the spiral return springs 150 and 152 are not
pre-tensioned. Thus the actuator assembly 110 can also be said to
have no pre-tensioning.
[0073] As illustrated in both FIGS. 4 and 5, the lower surface 157
of the second spiral return spring 150 is proximate to the upper
surface 155 of the first spiral return spring 152. Because the
spiral return springs 150 and 152 are oppositely wound once
assembled, the spring coils are less likely to become entwined if
they contact.
[0074] In an alternative embodiment, a plastic washer (not shown)
can be positioned between the first spiral return spring 152 and
the second spiral return spring 150 to eliminate the possibility of
contact and therefore reduce the possibility of the spiral return
springs 150 and 152 becoming entwined.
[0075] Operation of the actuator assembly 110 is as follows. FIG. 5
shows the actuator assembly 110 in a neutral position A. As the
gear wheel 116 is rotated in a first direction (clockwise when
viewing FIG. 5) by the electric motor (not shown), the second end
164 of the drive formation 160 abuts against the outer arm 154 of
the first spiral return spring 152 to move the outer arm 154. The
inner arm 156 of the first spiral return spring 152 does not move
because it is located in a spigot slot 128, and the spigot 124 is
integral with the chassis 114. As the gear wheel 116 is rotated in
the first direction, the first spiral return spring 152 winds up as
the outer arm 154 moves clockwise relative to the inner arm 156. In
this embodiment, the first spiral return spring 152 is wound up due
to the rotation of the drive formation 160 relative to the chassis
114.
[0076] With the first spiral return spring 152 in a first actuated
position B, the outer arm 154 of the first spiral return spring 152
acts upon the second end 164 of the drive formation 160 to bias the
gear wheel 116 counter-clockwise back towards the neutral position
A. After actuation to the first actuated position B, the gear wheel
116 is biased towards the neutral position A by the first spiral
return spring 152.
[0077] As the gear wheel 116 is rotated in the first direction, the
outer arm 140 of the second spiral return spring 150 remains
stationary as the first end 162 of the drive formation 160 moves
away from it. The outer arm 140 abuts the first end 159 of the stop
158, which does not move because it is integral with the chassis
114. As with the first spiral return spring 152, the inner arm 142
of the second spiral return spring 150 does not move because it is
located in the spigot slot 128 and the spigot 124 is integral with
the chassis 114. As the gear wheel 116 is rotated clockwise,
neither of the arms 140 and 142 of the second spiral return spring
150 move, and thus the second spiral return spring 150 is not
unwound as the first spiral return spring 152 is wound. Therefore,
the actuator assembly 110 does not have to work against the second
spiral return spring 150 when driving the actuator assembly 110 in
the first direction. When the gear wheel 116 is rotated in the
first direction, the second spiral return spring 150 is idle.
[0078] The electric motor (not shown) can also drive the gear wheel
116 in a second direction (counter-clockwise when viewing FIG. 5)
towards a second actuated position C. Operation of the actuator
assembly 110 in the second direction is identical to that in the
first direction except that the second spiral return spring 150
biases the gear wheel 116 towards the neutral position A from the
second actuated position C. Similarly, the first spiral return
spring 152 is not unwound as the second spiral return spring 150
winds up, and the first spiral return spring 152 is idle.
[0079] FIGS. 6, 7 and 8, illustrate part of an actuator assembly
210 according to a third embodiment of the present invention with
features identical or similar to the actuator assembly 110 (second
embodiment) numbered 100 greater.
[0080] The third embodiment differs from the second embodiment only
in that the first spiral return spring 152 and the second spiral
return spring 150 are pre-tensioned when the gear wheel 116 is in
the neutral position A.
[0081] FIG. 6 shows both the first spiral return spring 252 and the
second spiral return spring 250 in a free state (note in particular
the relative positions of outer arms 240 and 254 and inner arms 242
and 256). As in the second embodiment, the first spiral return
spring 252 and the second spiral return spring 250 are identical to
each other.
[0082] In FIG. 7, the first spiral return spring 252 and the second
spiral return spring 250 are in an assembled position. By comparing
FIG. 6 (spiral return springs 252 and 250 in their free state), it
can be seen with FIG. 7 (spiral return springs 252 and 250 in their
assembled state) that the relative positions of the inner arms 242
and 256 and the outer arms 240 and 254 of the spiral return springs
252 and 250 have changed. Specifically, the outer arm 240 of the
second spiral return spring 250 has moved counter-clockwise
relative to the inner arm 242, and the outer arm 254 of the first
spiral return spring 252 has moved clockwise relative to the inner
arm 256. In the assembled position of FIG. 7, both the first spiral
return spring 252 and the second spiral return spring 250 are
pre-tensioned. This position corresponds to the neutral position
A.
[0083] Operation of the actuator assembly 210 is identical to the
second embodiment except that an electric motor must overcome the
initial pre-tension of the first spiral return spring 252 or the
second spiral return spring 250 to move a gear wheel 216 in either
the first or second direction. Thus, more effort is required from
the electric motor (not shown) to rotate the gear wheel 216 in the
first or second direction.
[0084] A comparison of FIG. 7 (neutral position A) and FIG. 8
(first actuated position B) shows the relative positions of the
first spiral return spring 252 and the second spiral return spring
250 after actuation.
[0085] Because the actuator assembly 210 must overcome the
pre-tension of either the first spiral return spring 252 or the
second spiral return spring 250 when actuating the gear wheel 216
in either the first or second direction from the neutral position
A, the neutral position A is better defined in comparison to
actuator assemblies where the spiral return springs are not
pre-tensioned in the neutral position.
[0086] Furthermore, it is possible to set the amount of pre-tension
in the spiral return springs 252 and 250 to better overcome any
friction in the actuator assembly 210, and thus the gear wheel 216
will always be returned to the neutral position A. In an actuator
assembly that includes a degree of friction in the components, the
pre-tension of the first spiral return spring 252 and the second
spiral return spring 250 will ensure that the gear wheel 216 is
returned to the neutral position A.
[0087] FIG. 9 and FIG. 10 show part of an actuator assembly 310
according to a fourth embodiment of the present invention with
features identical or similar to the actuator assembly 110 (second
embodiment) numbered 200 greater.
[0088] In FIG. 9, the actuator assembly 310 includes a gear wheel
316 with a drive formation 360. The drive formation 360 differs
from the drive formation 160 of the second embodiment in that it
extends from an outer wall 330, as opposed to being distinct from
an outer wall 230. The drive formation 360 has a first end 362 and
a second end 364.
[0089] The actuator assembly 310 includes a first spiral return
spring 352 having an outer arm 354 and an inner arm 356 and a
second spiral return spring 350 having an outer arm 340 and an
inner arm 342. The outer arms 340 and 354 differ from those of the
second embodiment in that they are bent to enable positive location
on a first end 362 and a second end 364 of the drive formation 360.
The inner arms 342 and 356 are also profiled to be able to locate
in a spigot slot 328 of a spigot 324 and also to locate around a
pivot pin 320.
[0090] FIG. 10 shows the actuator assembly 310 after it has been
assembled as follows. The first spiral return spring 352 and the
second spiral return spring 350 are assembled onto a chassis 314
such that the inner arms 342 and 356 locate in the spigot slot 328
of the spigot 324. It can be seen from FIGS. 9 and 10 that while
the first spiral return spring 352 and the second spiral return
spring 350 are identical, they are assembled onto the chassis 314
such that they are wound in opposite directions relative to each
other by simply turning the second spiral return spring 350 upside
down.
[0091] The gear wheel 316 is then positioned on the pivot pin 320
such that the outer arm 340 of the second spiral return spring 350
abuts the first end 362 of the drive formation 360, and the outer
arm 354 of the first spiral return spring 352 abuts the second end
364 of the drive formation 360.
[0092] In FIG. 10, the actuator assembly 310 is in a neutral
position A. The inner arms 356 and 342 and the outer arms 354 and
340 of the spiral return springs 350 and 352 are still in their
same relative positions, and thus the spiral return springs 352 and
350 are still in their free state once assembled onto the chassis
314, i.e., the spiral return springs 352 and 350 are not
pre-tensioned. Thus, the actuator assembly 310 of FIGS. 9 and 10
has no pre-tensioning.
[0093] Operation of the actuator assembly 310 is as follows. As the
gear wheel 316 is rotated in a first direction (clockwise when
viewing FIG. 10) by the electric motor (not shown), the second end
364 of the drive formation 360 abuts the outer arm 354 of the first
spiral return spring 352 to move the outer arm 354. The inner arm
356 of the first spiral return spring 352 does not move because it
is located in the spigot slot 328, and the spigot 324 is integral
with the chassis 314. As the gear wheel 316 is rotated in the first
direction, the first spiral return spring 352 winds up as the outer
arm 354 moves clockwise relative to the inner arm 356.
[0094] With the first spiral return spring 352 in a first actuated
position B, the outer arm 354 of the first spiral return spring 352
acts upon the second end 364 of the drive formation 360 to bias the
gear wheel 316 back towards the neutral position A. After actuation
to the first actuated position, the gear wheel 316 is biased
towards the neutral position A by the first spiral return spring
352.
[0095] As the gear wheel 316 is rotated in the first direction, the
outer arm 340 of the second spiral return spring 350 remains
stationary as the first end 362 of the drive formation 360 moves
away from it. As with the first spiral return spring 352, the inner
arm 342 of the second spiral return spring 350 does not move
because it is located in the spigot slot 328, and the spigot 324 is
integral with the chassis 314. As the gear wheel 316 rotates
clockwise, neither the outer arm 340 nor the inner arm 342 of the
second spiral return spring 350 moves. Therefore, the second spiral
return spring 350 is not unwound as the first spiral return spring
352 is wound. The actuator assembly 310 does not have to work
against the second spiral return spring 350 when driving the
actuator assembly 310 in the first direction. When the gear wheel
316 is rotated in the first direction, the second spiral return
spring 350 is idle.
[0096] The electric motor (not shown) can also rotate the gear
wheel 316 in a second direction (counter-clockwise when viewing
FIG. 10) towards a second actuated position C. Operation of the
actuator assembly 310 in the second direction is identical to that
in the first direction except that the second spiral return spring
350 biases the gear wheel 316 towards the neutral position A from
the second actuated position C. Similarly, the first spiral return
spring 352 is not unwound as the second spiral return spring 350
winds up, and the first spiral return spring 352 is idle.
[0097] FIG. 11 and FIG. 12 show part of an actuator assembly 410
according to a fifth embodiment of the present invention with
features identical or similar to the actuator assembly 110 (second
embodiment) numbered 300 greater.
[0098] The fifth embodiment is identical to the second embodiment
except the spigot 124 is integral with a gear wheel 116 to form a
combined gear wheel 416. A first spiral return spring 450 and a
second spiral return spring 452 have swapped positions, i.e., the
first spiral return spring 450 is shown as the top spring when
viewing FIG. 11 and is positioned above the second spiral return
spring 452, shown as the bottom spring when viewing FIG. 11.
[0099] FIG. 11 shows that a spigot 424 is integral to a combined
gear wheel 416. Typically, the strength requirements of the spigot
424 and the combined gear wheel 416 are similar. Therefore the
combined gear wheel 416 and the spigot 424 can be produced as a
one-piece molding.
[0100] FIG. 12 shows the actuator assembly 410 after it has been
assembled as follows. The second spiral return spring 452 is
assembled onto the combined gear wheel 416 such that an outer arm
454 abuts a second end 464 of a drive formation 460, and an inner
arm 456 locates in a spigot slot 428. The first spiral return
spring 450 is then assembled onto the combined gear wheel 416 such
that an outer arm 440 abuts a first end 462 of the drive formation
460 and an inner arm 442 locates in the spigot slot 428.
[0101] As in the second embodiment, while the first spiral return
spring 450 and the second spiral return spring 452 are identical,
they are assembled onto the combined gear wheel 416 such that they
are wound in opposite directions relative to each other by simply
turning the second spiral return spring 452 upside down.
[0102] Once the spiral return springs 450 and 452 have been
assembled onto the combined gear wheel 416, the combined gear wheel
416 can be mounted on a pivot pin 420 on a chassis 414.
[0103] Because the first spiral return spring 450 and the second
spiral return spring 452 are mounted on the combined gear wheel 416
as opposed to the chassis 414, it is possible for both the spiral
return springs 450 and 452 and the combined gear wheel 416 to be
provided as a subassembly, which can then subsequently be assembled
onto the chassis 414. This makes assembly more efficient because
the potentially complex step of locating the spiral return springs
450 and 452 can be conducted remotely from the chassis 414.
[0104] Operation of the actuator assembly 410 is as follows. In
reference to FIG. 12, as the combined gear wheel 416 is rotated in
the first direction (clockwise), the outer arm 440 of the first
spiral return spring 450 remains stationary as the first end 462 of
the drive formation 460 moves away from the outer arm 440 and the
outer arm 440 abuts first end 459 of a stop 458, that does not move
because it is integral with the chassis 414. The inner arm 442 of
the first spiral return spring 450 moves from the neutral position
A to the first actuated position B because it is located in the
spigot slot 428, and the spigot 424 is integral with the combined
gear wheel 416. As the combined gear wheel 416 is rotated, the
first spiral return spring 450 winds up as the inner arm 442 moves
towards the outer arm 440, which is prevented from moving in the
first direction by the stop 458. In this embodiment, the first
spiral return spring 450 is wound up due to the rotation of the
spigot 424 relative to the chassis 414 and not due to rotation of
the drive formation 460 relative to the chassis 414.
[0105] In the first actuated position B, the inner arm 442 of the
first spiral return spring 450 acts upon the spigot slot 428 of the
spigot 424 to bias the combined gear wheel 416 back towards the
neutral position A. After being actuated to the first actuated
position, the combined gear wheel 416 is biased towards the neutral
position A by the first spiral return spring 450.
[0106] As the combined gear wheel 416 is rotated in the first
direction, the second end 464 of the drive formation 460 abuts the
outer arm 454 of the second spiral return spring 452 to move the
outer arm 454 of the second spiral return spring 452. The inner arm
456 of the second spiral return spring 452 also moves because it is
located in the spigot slot 428, and the spigot 424 is integral with
the combined gear wheel 416. As the combined gear wheel 416 is
rotated in the first direction, the second spiral return spring 452
is not wound up because the inner arms 442 and 456 and the outer
arms 440 and 454 do not move relative to each other. The electric
motor (not shown) does not have to work against the second spiral
return spring 452 when driving the combined gear wheel 416 in the
first direction. In this embodiment, the second spiral return
spring 452 can be classed as idle, but in contrast to the second,
third and fourth embodiments, the second spiral return spring 452
is idle because both the inner arm 456 and the outer arm 454 of the
second spiral return spring 452 move with the combined gear wheel
416. Hence, there is no relative movement of the inner arm 456 and
the outer arm 454, as opposed to neither the inner arm 456 nor the
outer arm 454 moving with the combined gear wheel 416 where there
is no movement and no relative movement of the inner arm 456 or the
outer arm 454.
[0107] In reference to FIGS. 13 and 14, part of an actuator
assembly 510 according to a sixth embodiment of the present
invention is shown, with features identical or similar to the
actuator assembly 410 (fifth embodiment) numbered 100 greater.
[0108] The sixth embodiment is identical to the fifth embodiment
except that the actuator assembly 510 has a square spigot 524 and
modified spring arms.
[0109] In FIG. 13, inner arms 542 and 556 are both bent to form a
square profile that locates around the square spigot 524 and avoid
the need for a slot in the square spigot 524 to retain the inner
arms 542 and 556. This is advantageous because the square spigot
524 is less likely to burst result in failure if there is no slot.
The operation of the actuator assembly 510 is identical to the
fifth embodiment.
[0110] FIGS. 15 to 18C show part of an actuator assembly 610
according to a seventh embodiment of the present invention with
features identical or similar to the actuator assembly 410 (fifth
embodiment) numbered 200 greater. The seventh embodiment is
identical and operates in the same way as the fifth embodiment
except that the first and second spiral return springs are
pre-tensioned when in the neutral position.
[0111] A comparison of FIG. 15 shows the spiral return springs 650
and 652 in a free state, and FIG. 16 shows the spiral return
springs 650 and 652 in a neutral position A. FIGS. 18A and 18B, in
particular the relative positions of the spiral return spring outer
arms 640 and 654 and inner arms 642 and 656, show the spiral return
springs 650 and 652 in pre-tension as previously illustrated in the
third embodiment.
[0112] FIG. 18B (neutral position A) and FIG. 18C (first actuated
position B) show the positions of the spiral return springs 650 and
652 before and after actuation in the first direction to the first
actuated position B.
[0113] FIGS. 19 to 21 show part of an actuator assembly 710
according to an eighth embodiment of the present invention with
features identical or similar to the actuator assembly 410 (fifth
embodiment) numbered 300 greater. The actuator assembly 710 is
identical to the fifth embodiment except that the first and second
spiral return springs 750 and 752 are mounted on opposite sides of
a gear wheel 716.
[0114] In FIGS. 19 and 20, the gear wheel 716 has an upper surface
770 and a lower surface 772, and the gear wheel 716 including an
upper drive formation 760A is mounted on the upper surface 770 and
a lower drive formation 760B is mounted on the lower surface 772.
The upper drive formation 760A has a first end 762A, and the lower
drive formation 760B has a second end 764B.
[0115] The gear wheel 716 has a spigot 724 that is integral with
and extends from the upper surface 770 and the lower surface 772 of
the gear wheel 716 and includes a spigot slot 728.
[0116] The first and second spiral return springs 750 and 752 are
identical to those of the fifth embodiment. An upper stop 758A is
mounted on and integral with an upper part of a chassis 714, and a
lower stop 758B is mounted on and integral with a lower part of the
chassis 714. The upper stop 758A has a first end 759A, and the
lower stop 758B has a second end 761B.
[0117] FIG. 21 shows the actuator assembly 710 after it has been
assembled as follows. The first spiral return spring 750 is
assembled onto the upper surface 770 of the gear wheel 716 such
that an outer arm 740 abuts the first end 762A of the upper drive
formation 760A, and an inner arm 742 locates in the spigot slot
728. The second spiral return spring 752 is assembled onto the
lower surface 772 of the gear wheel 716 such that an outer arm 754
abuts the second end 764B of the lower drive formation 760B, and an
inner arm 756 locates in the spigot slot 728. It can be seen from
FIG. 19 and FIG. 20 that the first and second spiral return springs
750 and 752 are assembled such that they are counter-rotating. This
can be achieved by simply turning one of the spiral return springs
750 and 752 upside down.
[0118] By locating the first and second spiral return springs 750
and 752 on either side of the gear wheel 716, the possibility of
the spiral return springs 750 and 752 become entwined is eliminated
because they are no longer in physical contact. After assembling
the spiral return springs 750 and 752 onto the gear wheel 716, the
gear wheel 716 is then located onto a pivot 720 mounted on the
chassis 714.
[0119] Operation of the actuator assembly 710 is as follows. As the
gear wheel 716 is rotated in the first direction (clockwise) by the
electric motor (not shown), the outer arm 740 of the first spiral
return spring 750 remains stationary as the first end 762A of the
upper drive formation 760A moves away from it, and the outer arm
740 abuts the first end 759A of the upper stop 758A, which does not
move because it is integral with the chassis 714. The inner arm 742
of the first spiral return spring 750 moves because it is located
in the spigot slot 728, and the spigot 724 is integral with the
gear wheel 716. As the gear wheel 716 is rotated, the first spiral
return spring 750 winds up as the inner arm 742 moves towards the
outer arm 740, which is prevented from moving in the first
direction by a stop 758.
[0120] After actuation in the first direction to the first actuated
position B, the inner arm 742 of the first spiral return spring 750
acts upon the spigot slot 728 of the spigot 724 to bias the gear
wheel 716 back towards the neutral position A.
[0121] As the gear wheel 716 is rotated in the first direction, the
second end 764B of the lower drive formation 760B abuts the outer
arm 754 of the second spiral return spring 752 to move the outer
arm 754 of the second spiral return spring 752. The inner arm 756
of the second spiral return spring 752 also moves because it is
located in the spigot slot 728, and the spigot 724 is integral with
the gear wheel 716. As the gear wheel 716 is rotated in the first
direction, the second spiral return spring 752 is not wound because
the inner arms 742 and 756 and the outer arms 740 and 754 both move
and thus do not move relative to each other.
[0122] FIGS. 22 to 24 show part of an actuator assembly 810
according to a ninth embodiment of the present invention with
features identical or similar to the actuator assembly 410 (fifth
embodiment) numbered 400 greater. The ninth embodiment is identical
to the fifth embodiment except that the first and second spiral
return springs 850 and 852 are integrated to form a combined spring
880.
[0123] In reference to FIG. 22 and FIG. 23, the actuator assembly
810 includes a spring arrangement in the form of the combined
spring 880. The combined spring 880 is a single component having a
common inner arm 842 (as opposed to separate inner arms 442 and 456
of the fifth embodiment), a first outer arm 854, and a second outer
arm 840. The combined spring 880 is arranged such that it is wound
counter-clockwise from the common inner arm 842 to the second outer
arm 840 to form an upper spring portion 884 corresponding to and
behaving in the same way as the first spiral return spring 450 of
the fifth embodiment and clockwise from the common inner arm 842 to
the first outer arm 854, forming a lower spring portion 886
corresponding to and behaving in the same way as the second spiral
return spring 452 of the fifth embodiment.
[0124] FIG. 24A shows a blank of the developed combined spring 880.
The combined spring 880 is formed by creating an appropriate sized
blank of substantially rectangular shape having a length X and a
height Y and cutting a slot 841 of height S about a center line C
of the blank. The remaining part of the blank length that is not
cut to form the slot 841 defines the length of the common inner arm
842. The upper spring portion 884 is then wound in one direction
about the common inner arm 842, and the lower spring portion 886 is
wound in the opposite direction such that the upper spring portion
884 and lower spring portion 886 are counter-rotating. The slot 841
prevents the upper spring portion 884 and the lower spring portion
886 from becoming entwined when the upper spring portion 884 and
the lower spring portion 886 are wound in opposite directions and
during subsequent operation when assembled in the actuator assembly
810. It can be seen from FIG. 24A that the common inner arm 842 has
a height Y, and the first outer arm 854 and the second outer arm
840 have combined heights that equal the height of the blank,
taking into consideration the slot 841 height S.
[0125] The combined spring 880 is assembled onto the gear wheel 816
such that the first outer arm 854 abuts a second end 864 of a drive
formation 860, and the second outer arm 840 abuts a first end 862
of the drive formation 860. The common inner arm 842 locates in a
spigot slot 828.
[0126] By providing the combined spring 880 as opposed to the two
spiral return springs 450 and 452 of the fifth embodiment, assembly
is easier by virtue of having one less component. It is also
possible to arrange the common inner arm 842 such that the upper
spring portion 884 and the lower spring portion 886 portion of the
combined spring 880 are spaced apart, further reducing the
possibility of the portions become entwined.
[0127] Furthermore, the combined spring 880 can be assembled either
way without effecting operation of the assembly, and thus assembly
is more efficient.
[0128] Operation of the actuator assembly 810 is identical to the
fifth embodiment, with the upper spring portion 884 acting in the
same way as the first spiral return spring 450 and the lower spring
portion 886 acting in the same way as the second spiral return
spring 452.
[0129] FIG. 24B shows an alternative combined spring blank 980. The
alternative combined spring blank 980 differs from the blank of
FIG. 24A in that a slot 941 is formed by first creating a hole 995
at a point on the center line C corresponding to the edge of a
common inner arm 942 and then shearing the alternative spring blank
980 along the center line towards the hole 995. An upper spring
portion 984 and a lower lower spring portion 986 are then deformed
to create a gap (not shown) that prevents the upper and lower
spring portions 984 and 986 from becoming entwined when the upper
and lower spring portions 984 and 986 are wound in opposite
directions and during subsequent operation when assembled in the
actuator assembly 910.
[0130] FIG. 24C shows an alternative combined spring blank 1080.
The alternative combined spring blank 1080 differs from the
alternative combined spring blank 980 of FIG. 24A in that the
alternative combined spring blank 1080 is substantially S-shaped
(with square corners) as opposed to substantially rectangular
shaped. A combined spring is formed by folding the alternative
combined spring blank 1080 about a fold line F (situated half way
along the length of the blank) to create a common inner arm 1042
and then winding an upper portion 1084 and a lower portion 1086 in
opposite directions about the common inner arm. The common inner
arm 1042 will be twice the thickness of that of the blank used to
form the combined spring 880 because the blank is folded over onto
itself. It can be seen from FIG. 24C that the first and second
outer arms 1054 and 1040 are of height Y, i.e., they extend the
full height of the blank as opposed to those of the blank of FIG.
24A, which extends approximately half the height of the blank.
Because the blank is folded about the fold line F, the original
length of the blank is twice that of the blank of FIG. 24A.
[0131] In an alternative embodiment, the combined spring 880 could
be replaced by either a combined spring made from either of the
alternative combined spring blanks 980 or 1080.
[0132] While some of the features in the actuator assemblies of
FIGS. 1 to 25 have been described in relation to specific
embodiments, it is to be appreciated that, where appropriate, most
of the different features can be incorporated into the different
embodiments.
[0133] More particularly, either a square or cylindrical spigot can
be used in all of the embodiments, providing the spring inner arms
are modified accordingly.
[0134] All of the embodiments using a first and second spiral
return springs can be modified to have either pre-tension or no
pre-tension in the neutral position.
[0135] The actuator assemblies described in FIGS. 1 to 25 can be
used to drive a linkage connected to the gear wheel in the first
and second direction. The actuator assemblies are arranged such
that after being driven in the first or second direction, the gear
wheel is returned to the neutral position under the action of the
spiral return spring.
[0136] The linkage can be connected to a component of a device such
that the component can be powered in first or second directions to
first or second component positions. Typically, such devices also
include manual means to move the component between the first and
second component positions, both for convenience and in the event
of power failure. After power actuating the component in the first
or second direction, the fact that the actuator is returned to the
neutral position means that if the manual means is used to move the
component, it is not necessary to manually back drive the motor,
thus less effort is required.
[0137] An example of a device that is powered in first and second
directions is a powered locking latch. With reference to FIG. 26, a
latch assembly 88 including a latch 90 and the actuator assembly 10
is shown. The latch assembly 88 is typically used on a land
vehicle, such as a car or truck. The latch assembly 88 can be used
to secure a driver or passenger door closed or it can be used to
secure a trunk lid closed.
[0138] The latch 90 includes a locking mechanism 92 that is
connected via a first linkage 93 to a manual locking feature 94 and
via a second linkage 97 to a powered locking feature 96. The manual
locking feature 94 is typically connected to one or more of a sill
button (not shown, but typically mounted on an inside sill of a
door), an inside release lever (not shown), and a key mechanism
(not shown but typically mounted on the outside of a door). The
locking mechanism 92 includes a lock link 98.
[0139] The actuator assembly 10 is connected to the powered locking
feature 96 via the linkage 25 (FIG. 1) such that the electric motor
12 (FIG. 1) can drive the linkage 25 in first or second directions.
Movement of the linkage 25 in the first direction from the neutral
position A moves the lock link 98 to a first component position
where the latch 90 is locked, and movement of the linkage 25 in the
second direction from the neutral position A moves the lock link 98
to a second component position where the latch 90 is unlocked. In
other embodiments, the component positions could correspond to, for
example, child safety on and child safety off positions.
[0140] After the electric motor 12 has driven the lock link 98 to
the locked position, the electric motor 12 is returned to the
neutral position A by the bias of the spiral spring. The latch 90
can now be power unlocked by driving the electric motor 12 in the
second (opposite direction), or manually unlocked via the manual
locking means 94. Because the electric motor 12 is in the neutral
position A, the manual locking means 94 does not have to manually
back drive the electric motor 12, and therefore operation of the
sill button, key, or inside release lever does not require the
extra effort of having to manually back drive the electric motor
12.
[0141] Thus, it can be seen that by employing the actuator assembly
10 of the present invention in a powered locking latch, the
electric motor 12 does not have to be back driven, be it manually
or by operating the electric motor 12 in the opposite
direction.
[0142] In other embodiments, the actuator assembly 10 could be
replaced by any of the actuator assemblies of FIGS. 4 to 25.
[0143] In another embodiment, the gear wheel 16 could be directly
connected to the locking mechanism 92, as opposed to via the
linkage 25.
[0144] Although preferred embodiments of the present invention have
been disclosed, a worker of ordinary skill in this art would
recognize that certain modifications would come within the scope of
this invention. For that reason, the following claims should be
studied to determine the true scope and content of this
invention.
* * * * *