Information
-
Patent Grant
-
6705138
-
Patent Number
6,705,138
-
Date Filed
Monday, November 25, 200221 years ago
-
Date Issued
Tuesday, March 16, 200420 years ago
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Inventors
-
-
Examiners
Agents
-
CPC
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US Classifications
Field of Search
US
- 070 149
- 070 218
- 070 422
- 070 472
- 292 3363
-
International Classifications
-
Abstract
An outside transmission assembly of a lock includes an outside spindle, an outside hub for rotatably receiving the outside spindle, a cam received in the outside spindle, a sleeve received in the cam, and a lug. The cam has an ear releasably engaged with a retractor. The lug has an arm and a ring formed on an end of the arm and mounted to the first end of the sleeve. The arm extends through the cam and the outside spindle. The cam and the outside spindle are turned jointly when the outside handle is turned. When the locking bar is moved to a locking position, the lug and the sleeve are moved away from the retractor. The cam is also moved away from the retractor such that the ear of the cam is disengaged from the retractor, allowing free rotation of the outside handle.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a clutch mechanism for a lock. In particular, the present invention relates to a clutch mechanism for a lock that allows the outer handle to rotate freely when the lock is in a locked state so that the internal parts of the lock will not be damaged.
2. Description of the Related Art
A conventional door lock generally includes an outer handle and an inner handle respectively attached to the outside and the inside of a door so that the latch bolt can be retracted by turning either one of the outer handle and the inner handle. When in a locked state, the outer handle could not be turned for retracting the latch bolt. It is, however, not uncommon that the user still applies force to the outer handle to an extent that is normally sufficiently large enough for retracting the latch bolt if the user is not aware of the locked state of the lock. Thus, the inner parts of the lock connected to the handle could be damaged by a torque resulting from the force applied to the outer handle. The situation worsens for a lock with lever type handles.
U.S. Pat. No. 6,041,630 discloses a lock having a clutch mechanism to solve this problem. The lock includes an inner handle having a locking bar received therein and an outer handle connected to a spindle with a retaining base received therein which has two first grooves defined therein. A cam is connected to the retaining base and has two second grooves which communicate with the first grooves so that a locking piece is movably received between the retaining base and the cam with a spring biased between the locking piece and the retaining base. The locking piece has two flanges movably received in the first grooves and the second grooves. A slide is movably received in the cam and contact the locking piece at one end thereof and the locking bar at the other end thereof so that the two flanges of the locking piece are disengaged from the second grooves when the locking bar is pushed. Therefore, the outer handle can be freely rotated. Nevertheless, there are too many elements for the clutch mechanism. The assembly procedure is too complicated and the overall cost is increased.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a clutch mechanism for a lock that allows easy assembly and that is easy to manufacture while allowing the outer handle to rotate freely when the lock is in a locked state so that the internal parts of the lock will not be damaged.
A lock mechanism in accordance with the present invention comprises:
a latch;
a retractor for retracting the latch;
an inside handle;
an inside spindle having a first end fixed to the inside handle to turn therewith and a second end, the inside spindle being operably connected to the retractor such that rotation of the inside spindle causes retraction of the latch;
a locking bar extending through the inside spindle and having a first end and a second end;
an inside hub for rotatably receiving the second end of the inside spindle;
an outside handle;
an outside spindle having a first end and a second end fixed to the outside handle to turn therewith, the first end of the outside spindle including a slot extending along a longitudinal direction of the outside spindle;
an outside hub for rotatably receiving the first end of the outside spindle;
a cam received in the first end of the outside spindle, the cam being movable relative to the outside spindle along a longitudinal direction of the outside spindle, the cam having an engaging notch, the cam further having an ear projecting outward therefrom, the ear of the cam being releasably engaged with the retractor such that rotation of the cam causes retraction of the latch;
a sleeve received in the cam and having a first end and a second end;
a lug having an arm and a ring formed on an end of the arm, the ring being so mounted to the first end of the sleeve that the sleeve is not turned when the arm is turned and that the arm and the sleeve are jointly movable along the longitudinal direction of the outside spindle, the arm extending through the engaging notch of the cam and the slot of the outside spindle, the cam and the outside spindle being turned jointly when the outside handle is turned; and
an elastic element mounted between the outside handle and the cam for biasing the ear of the cam to engage with the retractor;
wherein when the locking bar is moved to a locking position, the lug and the sleeve are moved away from the retractor, the cam is also moved away from the retractor such that the ear of the cam is disengaged from the retractor, allowing free rotation of the outside handle without causing retraction of the latch.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is an exploded perspective view of a lock in accordance with the present invention.
FIG. 2
is a sectional view of the lock in accordance with the present invention, wherein the lock is in an unlocked state.
FIG. 3
is an exploded perspective view of a clutch mechanism of the lock in accordance with the present invention.
FIG. 4
is a sectional view similar to
FIG. 2
, wherein the lock is in a locked state.
FIG. 5
is a sectional view taken along plane
5
—
5
in
FIG. 4
, illustrating free rotation of the outer handle when the lock is in the locked state.
FIG. 6
is a sectional view similar to
FIG. 4
, illustrating unlocking operation by a key.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to
FIG. 1
, a lock in accordance with the present invention generally comprises an inside handle assembly
1
, an inside spindle
2
, an outside handle assembly
3
, an outside transmission assembly
4
, and a latch mechanism
5
.
The inside handle assembly
1
includes an inside handle (e.g., a lever
11
) and an inside rose assembly
12
mounted to an end of the inside lever
11
. The inside spindle
2
is mounted to an inside hub
13
that is mounted to an inner side of the inside rose assembly
12
. The outside handle assembly
3
includes an outside handle (e.g., a lever
31
) and an outside rose assembly
32
mounted to an end of the outside lever
31
. The outside transmission assembly
4
is mounted to an outside hub
33
that is mounted to an inner side of the outside rose assembly
32
. The outside hub
33
and the inside hub
13
are connected together by fasteners
60
. A locking bar
14
extends through the inside spindle
2
and is movable along a longitudinal direction of the inside spindle
2
. A push button
15
is attached to an end of the locking bar
14
and exposed outside the inside lever
11
, as shown in FIG.
4
.
A cylinder
34
is mounted in a shank
310
of the outer lever
31
and has a cylinder bar
341
protruding therefrom. A seat
35
is securely mounted in the outside hub
33
for positioning the outer transmission assembly
4
. The latch mechanism
5
is mounted in the outside hub
33
and operably connected to the inner spindle
2
and the outer transmission assembly
4
. The latch mechanism
5
includes a latch
51
that extends out of the outside hub
33
via a notch
331
of the outside hub
33
. The latch
51
is retactable by a retractor
52
, and a catch
53
is movably received in the retractor
52
.
Referring to
FIGS. 2 and 3
, the outer transmission assembly
4
includes an outside spindle
41
having a first end received in the outside hub
33
and a second end fixed to the outside lever
31
to turn therewith. The outer transmission assembly
4
further includes a cam
42
received in the first end of the outer spindle
41
, a sleeve
43
received in the cam
42
, and a lug
44
.
The first end of the outside spindle
41
includes a slot
411
defined in a periphery thereof and extending along a longitudinal direction of the outside spindle
41
. The first end of the outside spindle
41
further includes a notch
412
defined in the periphery thereof. An elastic element
45
is mounted in the second end of the outside spindle
41
and around the cylinder bar
341
, with two ends of the elastic element
45
being attached between an end of the cylinder
34
and the cam
42
. The outside hub
33
includes a restraining recessed portion
332
and a groove
333
that are respectively in association with the slot
411
and the notch
412
of the outside spindle
41
, which will be described later.
The cam
42
includes an ear
421
projecting radially outward from a periphery thereof and an engaging notch
422
defined in the periphery thereof. Preferably, the ear
421
is diametrically opposed to the engaging notch
422
. As illustrated in
FIG. 2
, the cam
42
is biased by the elastic element
45
such that the ear
421
of the cam
42
is normally engaged with the retractor
52
when the lock is in an unlocked state.
Still referring to
FIGS. 1 through 3
, the sleeve
43
includes a slot
432
in an end face of an end
431
thereof, and a receptacle
433
is defined in the other end of the sleeve
43
. The lug
44
includes an arm
442
and a ring
441
formed on an end of the arm
442
. The ring
441
is pivotally mounted around the end
431
of the sleeve
43
. The other end
142
of the locking bar
14
is securely engaged in the slot
432
of the end
431
of the sleeve
43
, allowing joint movement (including longitudinal movement and rotational movement) of the locking bar
14
and the sleeve
43
. The cylinder bar
341
of the cylinder
34
is securely engaged in the receptacle
433
of the sleeve
43
, allowing joint rotation of the cylinder bar
341
and the sleeve
43
. The arm
442
of the lug
44
extends through the engaging notch
422
of the cam
42
and the slot
411
of the outside spindle
41
.
In assembly, as illustrated in
FIG. 2
, the engaging notch
422
of the cam
42
is aligned with the slot
411
of the outside spindle
41
to allow the arm
442
of the lug
44
to extend through the engaging notch
422
of the cam
42
and the slot
411
of the outside spindle
41
. Thus, the sleeve
43
and the cam
42
may move jointly along a longitudinal direction of the outside spindle
41
, And the cam
42
and the outside spindle
41
may turn jointly. Further, the arm
442
of the lug
44
extends into the restraining recessed portion
332
of the outside hub
33
. The ear
421
of the cam
42
extends through an opening
351
of the seat
35
and is operably connected to the retractor
52
.
Still referring to
FIG. 2
, when the lock is in an unlocked state and when the outside lever
31
is turned, the outside spindle
41
turns together with the outside lever
31
. Since the arm
442
of the lug
44
extends through the slot
411
of the outside spindle
41
and the engaging notch
422
of the cam
42
, the cam
42
is also turned and thus actuates the retractor
52
, causing retraction of the latch
51
and thus allowing opening of the door to which the lock is mounted. Since the ring
441
of the lug
44
is pivotally mounted around the end
431
of the sleeve
43
, the sleeve
43
is not turned when the outside spindle
41
is turned. The latch
51
returns to its initial position when the outside lever
31
is released.
Referring to
FIG. 4
, when the push button
15
is pushed, the lolling bar
14
is moved inward until two side walls
530
of the catch
53
are respectively engaged in two engaging notches
141
on the locking bar
14
under the action of a spring
531
attached between the outside hub
33
and a connecting wall
532
between the side walls
530
of the catch
53
. Since the other end
142
of the locking bar
14
is securely engaged in the slot
432
of the end
431
of the sleeve
43
, inward movement of the locking bar
14
also causes the sleeve
43
and the lug
44
to move away from the retractor
52
. Thus, the ear
421
of the cam
42
passes trough the opening
351
of the seat
35
and is thus disengaged from the retractor
52
. The ear
421
of the cam
42
is moved to the notch
412
of the outside spindle
41
and the groove
333
of the outside hub
33
.
Referring to
FIG. 5
, when the outside lever
31
is turned while the lock is in the locked state shown in
FIG. 4
, since the ear
421
of the cam
42
is disengaged from the retractor
52
, the outside lever
31
turns freely without causing retraction of the latch
51
. Thus, damage to the inner parts of the lock resulting from turning of the outside lever
31
while the lock is in the locked state is avoided. The maximum pivotal movement of the outside lever
31
is generally 45 degrees, and it is determined by the arcuate length of the restraining recessed portion
332
of the outside hub
33
that receives the arm
442
of the lug
44
. Namely, when the outside lever
31
is turned, movement of the arm
442
of the lug
44
is limited by two ends of the restraining recessed portion
332
of the outside hub
33
. Further, the groove
333
of the outside hub
33
has an appropriate arcuate length to allow the ear
421
of the lug
44
to turn through a predetermined angle in the outside hub
33
and to allow longitudinal movement of the ear
421
. Further, the depths of the slot
411
of the outside spindle
41
and the raining recessed portion
332
of the outside hub
33
allow longitudinal movement of the arm
442
away from the outside hub
33
.
Referring to
FIG. 6
, when a proper key (not labeled) is inserted into the cylinder
34
and turned through a predetermined angle, the sleeve
43
is turned, as the cylinder bar
341
of the cylinder
34
is securely engaged in the receptacle
433
of the sleeve
43
. The locking bar
14
is also turned, as the other end
142
of the locking bar
14
is securely engaged in the slot
432
of the end
431
of the sleeve
43
. Thus, the engaging notches
141
(
FIG. 2
) of the locking bar
14
are disengaged from the side walls
530
of the catch
53
. The lock is no longer in the locked state, as the locking bar
14
returns to its initial position shown in
FIG. 2
under the action of a return spring
140
. The sleeve
43
, the lug
44
, and the cam
42
return to their initial position shown in
FIG. 2
under the action of the elastic element
45
.
According to the above description, it is appreciated that the outer transmission assembly
4
in accordance with the present invention provides a clutch mechanism that allows easy assembly and that is easy to manufacture while allowing the outer handle to rotate freely when the lock is in a locked state so that the internal parts of the lock will not be damaged.
Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the scope of the invention as hereinafter claimed.
Claims
- 1. A lock comprising:a latch; a retractor for retracting the latch; an inside handle; an inside spindle having a first end fixed to the inside handle to turn therewith and a second end, the inside spindle being operably connected to the retractor such that rotation of the inside spindle causes retraction of the latch; a locking bar extending through the inside spindle and having a first end and a second end; an inside hub for rotatably receiving the second end of the inside spindle; an outside handle; an outside spindle having a first end and a second end fixed to the outside handle to turn therewith, the first end of the outside spindle including a slot extending along a longitudinal direction of the outside spindle; an outside hub for rotatably receiving the first end of the outside spindle; a cam received in the first end of the outside spindle, the cam being movable relative to the outside spindle along a longitudinal direction of the outside spindle, the cam having an engaging notch, the cam further having an cam projecting outward therefrom, the ear of the cam being releasably engaged with the retractor such that rotation of the cam causes retraction of the latch; a sleeve received in the cam and having a first end and a second end; a lug having an arm and a zing formed on an end of the arm, the ring being so mounted to the first end of the sleeve that the sleeve is not turned when the arm is turned and that the arm and the sleeve are jointly movable along the longitudinal direction of the outside spindle, the arm extending through the engaging notch of the cam and the slot of the outside spindle, the cam and the outside spindle being turned jointly when the outside handle is turned; and an elastic element mounted between the outside handle and the cam for biasing the ear of the cam to engage with the retractor; wherein when the locking bar is moved to a locking position, the lug and the sleeve are moved away from the retractor, the cam is also moved away from the retractor such that the ear of the cam is disengaged from the retractor, allowing free rotation of the outside handle without causing retraction of the latch; wherein the first end of the sleeve includes a slot defined in an end face thereof for securely receiving the second end of the locking bar.
- 2. The lock as claimed in claim 1, wherein the outside handle is a lever.
- 3. The lock as claimed in claim 1, wherein the first end of the locking bar includes a push button mounted thereto, the lock further including a catch mounted in the outside hub, the catch having two side walls and a connecting wall between the side walls, a spring being attached between hem connecting wall of the catch and the outside hub, the locking bar including two engaging notches, the side walls of the catch being engaged with the engaging notches of the locking bar under action of the spring when the locking bar is moved to the locking position.
- 4. The lock as claimed in claim 3, wherein the second end of the sleeve includes a receptacle, the outside handle includes a cylinder mounted therein, the cylinder including a cylinder bar securely mounted in the receptacle of the sleeve such that the sleeve is turned when a key is inserted into the cylinder and turned, the locking bar being turned to cause the engaging notches of the locking bar to disengage from the side walls of the catch, the sleeve, the lug, and the cam returning to their original position under action of the elastic element.
- 5. The lock as claimed in claim 1, wherein the outside hub includes a restraining recessed portion allowing movement of the arm along the longitudinal direction of the outside spindle, the restraining recessed portion having two ends for limiting rotational movement of the arm.
- 6. The lock as claimed in claim 1, wherein the first end of the outside spindle includes a notch for slidingly receiving the ear of the cam.
- 7. The lock as claimed in claim 6, wherein the outside hub includes a groove for slidingly and rotatably receiving the ear of the cam.
- 8. The lock as claimed in claim 1, wherein the lock further includes a seat securely mounted in the outside hub for retaining the sleeve, the cam, and the lug.
- 9. The lock as claimed in claim 8, wherein the seat includes an opening through which the ear of the cam is passable.
- 10. A lock comprising:a latch; a retractor for retracting the latch; an inside handle; an inside spindle having a first end fixed to the inside handle to turn therewith and a second end, the inside spindle being operably connected to the retractor such that rotation of the inside spindle causes retraction of the latch; a locking bar extending through the inside spindle and having a first end and a second end; an inside hub for rotatably receiving the second end of the inside spindle; an outside handle; an outside spindle having a the end and a second end fixed to the outside handle to turn therewith, the first end of the outside spindle including a slot extending along a longitudinal direction of the outside spindle; an outside hub for rotatably receiving the first end of the outside spindle; a cam received in the first end of the outside spindle, the cam being movable relative to the outside spindle alone a longitudinal direction of the outside spindle, the cam having an engaging notch, the cam further having an ear projecting outward therefrom, the ear of the cam being releasably engaged with the retractor such that rotation of the cam causes retraction of the latch; a sleeve received in the cam and having a first end and a second end; a lug having an arm and a ring formed on an end of the arm, the ring being so mounted to the first end of the sleeve that the sleeve is not turned when the arm is turned and that the arm and the sleeve are jointly movable along the longitudinal direction of the outside spindle, the arm extending through the engaging notch of the cam and the slot of the outside spindle, the cam and the outside spindle being turned jointly when the outside handle is turned; and an elastic element mounted between the outside handle and the cam for biasing the ear of the cam to engage with the retractor; wherein when the locking bar is moved to a locking position, the lug and the sleeve are moved away from the retractor, the cam is also moved away from the retractor such that the ear of the cam is disengaged from the retractor, allowing free rotation of the outside handle without causing retraction of the latch; wherein the first end of the outside spindle includes a notch for slidingly receiving the ear of the cam.
- 11. The lock as claimed in claim 10, wherein the outside hub includes a groove for slidingly and rotatably receiving the ear of the cam.
- 12. The lock as claimed in claim 10, wherein the first end of the locking bar includes a push button mounted thereto, the lock further including a catch mounted in the outside hub, the catch having two side walls and a connecting wall between the side walls, a spring being attached between the connecting wall of the catch and the outside hub, the locking bar including two engaging notches, the side walls of the catch being engaged with the engaging notches of the locking bar under action of the spring when the locking bar is moved to the locking position.
- 13. The lock as claimed in claim 12, wherein the second end of the sleeve includes a receptacle, the outside handle includes a cylinder mounted therein, the cylinder including a cylinder bar securely mounted in the receptacle of the sleeve such that the sleeve is turned when a key is inserted into the cylinder and turned, the locking bar being turned to cause the engaging notches of the locking bar to disengage from the side walls of the catch, the sleeve, the lug, and the cam return to their original position under action of the elastic element.
- 14. The lock as claimed in claim 10, wherein the outside hub includes a restraining recessed portion allowing movement of the arm along the longitudinal direction of the outside spindle, the restraining recessed portion having two ends for limiting rotational movement of the arm.
- 15. The lock as claimed in claim 10, wherein the lock further includes a seat securely mounted in the outside hub for retaining the sleeve, the cam, and the lug.
- 16. The lock as claimed in claim 15, wherein the seat includes an opening through which the ear of the cam is passable.
- 17. The lock as claimed in claim 12, wherein the first end of the locking bar includes a push button mounted thereto, the lock further including a catch mounted in the outside hub, the catch having two side walls and a connecting wall between the side walls, a spring being attached between the connecting wall of the catch and the outside hub, the locking bar including two engaging notches, the side walls of the catch being engaged with the engaging notches of the locking bar under action of the spring when the locking bar, is moved to the locking position.
- 18. The lock as claimed in claim 17, wherein the second end of the sleeve includes a receptacle, the outside handle includes a cylinder mounted therein, the cylinder including a cylinder bar securely mounted in the receptacle of the sleeve such that the sleeve is turned when a key is inserted into the cylinder and turned, the locking bar being turned to cause the engaging notches of the locking bar to disengage from the side walls of the catch, the sleeve, the lug, and the cam returning to their original position under action of the elastic element.
- 19. A lock comprising:a latch; a retractor for retracting the latch; an inside handle; an inside spindle having a first end fixed to the inside handle to turn therewith and a second end, the inside spindle being operably connected to the retractor such that rotation of the inside spindle causes retraction of the latch; a locking bar extending through the inside spindle and having a first end and a second end; an inside hub for rotatably receiving the second end of the inside spindle; an outside handle; an outside spindle having a first end and a second end fixed to the outside handle to turn therewith, the first end of the outside spindle including a slot extending along a longitudinal direction of the outside spindle; an outside hub for rotatably receiving the first end of the outside spindle; a cam received in the first end of the outside spindle, the cam being movable relative to the outside spindle along a longitudinal direction of the outside spindle, the cam having an engaging notch, the cam further having an ear projecting outward therefrom, the ear of the cam being releasably enraged with the retractor such that rotation of the cam causes retraction of the latch; a sleeve received in the cam and having a first end and a second end; a lug having an arm and a ring formed on an end of the arm, the ring being so mounted to the first end of the sleeve that the sleeve is not turned when the arm is turned and that the arm and the sleeve are jointly movable along the longitudinal direction of the outside spindle, the arm extending through the engaging notch of the cam and the slot of the outside spindle, the cam and the outside spindle being turned jointly when the outside handle is turned; and an elastic element mounted between the outside handle and the cam for biasing the ear of the cam to engage with the retractor; wherein when the locking bar is moved to a locking position, the lug and the sleeve are moved away from the retractor, the cam is also moved away from the retractor such that the ear of the cam is disengaged from the retractor, allowing free rotation of the outside handle without causing retraction of the latch; wherein the lock further includes a seat securely mounted in the outside hub for retaining the sleeve, the cam, and the lug; and wherein the seat includes an opening through which the ear of the cam is passable.
US Referenced Citations (17)