Note: Descriptions are shown in the official language in which they were submitted.
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FLEXIBLE RELEASE FOR A LATCHING SYSTEM
Field of Invention
This invention relates to a flexible release for a latching system. In
particular,
this invention relates to a flexible release connector operably joining a key
cylinder
and a latch assembly.
Background of Invention
A typical deck lid for a trunk of a vehicle will have a latch which is
operably
by a key cylinder. Operation of the key cylinder will rotate a lever which is
linked to
a release pawl of the latch. Rotation of the release pawl will release the
ratchet or
detent fork which grips a keeper of a striker plate on the body of the
vehicle, thus
opening the deck lid.
Optionally, the vehicle can be provided with an inside release handle which is
operable from within the vehicle to allow the operator to open the trunk while
remaining in the vehicle.
Still further, the vehicle can be provided with an actuator operably connected
to the latch. The actuator has a receiver for receiving remotely transmitted
signals and
responsively rotates the release pawl to open the deck lid.
A conventional latch assembly, as illustrated in Figure 1, will have the
locking
cylinder 12 connected to the release pawl 14 of a latch 16 by a flexible cable
assembly
18 or a fixed link with some form of lost motion capabilities to accommodate
the
movement of the pawl as it ratchets with the detent fork 20 upon closing of
the deck
Iid.
A cable assembly usually consists of a cable 22, a balled end 24, a ferrule 26
and a cable end 28. The pawl 14 must have a cooperative fitting 30 to receive
the
balled end 24 of the cable 22. The housing of the latch 16 must have a tab 32
for
mounting the ferrule 26, through which the cable 22 extends, for controlling
the angle
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of attack between the cable 22 and the pawl 14. The key cylinder lever 34
requires a
clip 36 to attach the cable 22.
The cable assembly of the prior art has proven to be an effective operating
connection between the locking cylinder 12 and the latch 16. However, the
cable
assembly requires considerable labour to assemble and then install. Further,
the cable
assembly has a number of parts, all of which are susceptible to failure and
malfunction.
Summary of the Invention
The disadvantages of the prior art may be overcome by providing a biased
flexible link operably connecting a release pawl of a latch and a key
cylinder.
It is desirable to provide a relatively inexpensive flexible link for operably
connecting a release pawl of a latch to a lever of a key cylinder.
According to one aspect of the invention, there is provided a flexible link
for
operably connecting a release pawl of a latch to key cylinder. The link has a
connector at each end thereof for connecting to the release pawl at one end
and for
connecting to the key cylinder at the opposite end. The link has a flexing
section
intermediate of the ends. The flexing section has a bias for deflecting in an
axial or
predetermined direction.
Description of the Drawings
In drawings which illustrate embodiments of the invention,
Figure 1 is a perspective view of a prior art latch assembly;
Figure 2 is a perspective view of the latch assembly of incorporating the
flexible link of the present invention, illustrating the latch
assembly in a stand-by condition;
Figure 3 is a perspective view of the underside of the flexible link of the
present lnventlon;
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Figure 4 is perspective view of the top side of the flexible link of Figure
3;
Figure 5 is perspective view of the latch assembly of Figure 2,
illustrating the travel of the key cylinder pulling the flexible
link taut;
Figure 6 is perspective view of the latch assembly of Figure 2,
illustrating the travel of the key cylinder rotating the pawl for
releasing the detent fork; and
Figure 7 is perspective view of the latch assembly of Figure 2,
illustrating the latch assembly in a power releasing condition.
Description of the Invention
Referring generally to Figure 2, a flexible link 10 of the present invention
is
illustrated. The flexible link 10 operably connects a key cylinder 12 to a
latch 40.
Key cylinder 12 is conventional. Latch 40 is identical to latch 16, as
illustrated in
reference to the prior art of Figure 1, except as noted below. Like reference
numerals
identify identical parts of the prior art and the latch assembly incorporating
the present
mventlon.
Referring to Figures 3 and 4, flexible link 10 generally comprises a generally
flexible planar section 42 having connectors comprising axially extending
bosses 44
and 46 at opposite ends of the flexible link 10. Bosses 44 and 46 are
generally
cylindrical in shape and each has a pair of opposed resilient tangs 48
extending
radially of the bosses. Each end of the top side of the flexible link 10 has
longitudinally extending ribs 50.
Preferably, flexible link 10 is molded from a flexible low stretch plastic
material. Preferred materials include HYTREL manufactured by Dupont.
The planar section 42 has a generally rectangular cross-section and a
longitudinal extent which is greater than the width, which is greater than the
thickness. The geometry of the planar section 42 biases the flexible link 10
to bend or
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flex primarily in the axial direction and not side to side. Further, since the
ends of the
flexible link 10 has ribs 50 which stiffen the ends relative to the planar
section 42,
only the intermediate portion of the flexible link 10 will deflect.
Referring to Figure 2, the flexible link 10 is connected to cylinder lock 12
by
inserting boss 44 through a bore in the remote end of lever 34. Boss 46 is
inserted
through a bore in the end of release pawl 52. Release pawl 52 is identical to
release
pawl 14 of the prior art latch except that the release pawl 52 merely has a
bore for
receiving boss 46. Bosses 44 and 46 are inserted through the respective bores
overcoming the resiliency of the opposed tangs 48 to snap into place. Opposed
tangs
48 retain the flexible link 10 to the cylinder lock 12 and the latch 40.
Latch 40 is otherwise identical to prior art latch 16, except that on latch 40
cam 54 is positioned in place of tab 32.
As is apparent to those skilled in the art, the cost of manufacture and
assembly
of the latch assembly incorporating the flexible link of the present invention
is
substantially less than the cost of the prior art latch assembly. The housing
of the
latch and the release pawl are simplified, as well as the method of
assembling. The
flexible link can easily be molded rather than the more costly cable assembly
manufacture.
Figure 2, illustrates the latch assembly in a stand-by condition. The flexible
link 10 is biased to a deflected position. Release pawl 52 is in a latched
position. In
this condition, the deck lid on which the latch assembly is mounted may be
closed.
During closing, the detent fork 20 engages a keeper of a striker. As the
detent fork
rotates, it engages the release pawl 52 in a ratchet relation. Flexible link
10 will flex
or bend further accommodating the movement of the release pawl 52 during
engagement.
Referring to Figure 5, the lever 34 is rotated responsively to rotation of a
key
in key cylinder 12. Early rotation of key cylinder 12 will take up the slack
in the
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flexible link 10 which will become tensioned once the pre-travel has been
completed.
Further rotation of the key lever 34 in a releasing sense will apply a
releasing force to
pawl 52 which will responsively rotate to a release position to release detent
fork 20,
as illustrated in Figure 6. Upon release of the key in key cylinder 12,
tension in
flexible link 10 will be relieved, allowing release pawl 52 to return to the
stand-by
condition.
Cam surface 54 is positioned to engage planar section 42 during travel of the
flexible link 10 between the stand-by and release positions. Cam surface 54
will have
a height relative to the release pawl 52 and the key lever 34 such that cam
surface 54
will prevent flexible link 10 from flattening. When the release pawl 52 is in
the
release position, flexible link 10 will be fully extended. However, cam
surface 54
ensures that the flexible link 10 does not become planar and will induce at
least a
slight curvature therein. Since the flexible link 10 will have a bend, it will
have a
tendency or bias to bend outwardly relative to the latch 40 or axially
relative to the
longitudinal extent of the flexible link 10. In this manner, flexible link 10
will always
return in a predictable manner to the stand-by position as illustrated in
Figure 2 and
will not jam or inhibit movement of the key lever 34 or the release pawl 52.
Additionally, the latch 40 may be provided with a power actuator 56 operably
linked to release pawl 52 via lever 58. When activated, actuator 56 will
rotate lever
58 causing release pawl 52 to rotate between the stand-by and the release
positions.
Since flexible link 10 is able to flex, the powered movement of the pawl 52 is
independent of the key cylinder 12.
The preceding specific embodiment is illustrative of the practice of the
present
invention. It is to be understood, however, that other expedients known or
apparent to
those skilled in the art or disclosed herein may be employed without departing
from
the spirit of the invention.
