Note: Descriptions are shown in the official language in which they were submitted.
CA 02567191 2012-02-29
1
A DOOR LOCK THAT USES AN ELECTRIC
DRIVE TO REDUCE MECHANICAL FATIGUE
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a door lock, more
particularly to an electric door lock.
2. Description of the Related Art
In U.S. Patent Application Publication No.
2004/0245785, there is disclosed a conventional
electric door lock that includes a lock housing, a
latching member, a manual operating member, first and
second rotatable members, and an electric driving unit.
The latching member is movable between latching and
unlatching positions. The manual operating member
extends rotatably into the lock housing, is coupled to
the latching member, and is operable so as to move the
latching member between the latching and unlatching
positions. The first rotatable member is in the form
of a sector gear, and is mounted rotatably in the lock
housing. The second rotatable member is in the form of
a gear, is mounted rotatably in the lock housing, and
is coupled to the latching member. The second rotatable
member is rotatable relative to the lock housing from
a first angular position, where the latching member is
disposed at the latching position, to a second angular
CA 02567191 2006-11-03
2
position, where the latching member is disposed at the
unlatching position. The electric driving unit includes
a motor that is operable so as to drive rotation of the
first rotatable member.
In operation, at an initial position, in which the
latching member is at the latching position, activation
of the motor of the electric driving unit results in
clockwise rotation of the first rotatable member,
eventual engagement between the first and second
rotatable members, counter-clockwise rotation of the
second rotatable member to the second angular position,
thereby moving the latching member to the unlatching
position, and eventual disengagement between the first
and second rotatable members. At this time, reactivation
of the motor of the electric driving unit results in
counter-clockwise rotation of the first rotatable
member, eventual engagement between the first and second
rotatable members, clockwise rotation of the second
rotatable member to the first angular position, thereby
moving the latching member back to the latching position,
and eventual disengagement between the first and second
rotatable members.
The conventional electric door lock further includes
first and second switches, each of which deactivates
the motor of the electric driving unit when actuated.
The first switch is actuated when the second rotatable
member is rotated to the first angular position. The
CA 02567191 2006-11-03
3
second switch is actuated when the second rotatable
member is rotated to the second angular position.
The aforesaid conventional electric door lock is
disadvantageous in that, since each of gear teeth of
each of the first and second rotatable members has a
certain degree of thickness, proper engagement between
the first and second rotatable members cannot be ensured
during operation of the conventional electric door lock.
Moreover, the aforesaid conventional electric door lock
includes numerous switches.
SUMMARY OF THE INVENTION
Therefore, the object of the present invention is
to provide an electric door lock that can overcome the
aforesaid drawbacks of the prior art.
According to the present invention, an electric door
lock comprises an internal lock housing, a latching unit,
a manual operating member, first and second rotatable
members, and an electric driving unit. The internal lock
housing is formed with a handle mounting hole, and def Ines
an accommodating space. The latching unit is movable
between latching and unlatching positions. The manual
operating member is mounted rotatably on the internal lock
housing, extends into the accommodating space through the
handle mounting hole, and is coupled to the latching unit.
The manual operating member is rotatable relative to the
internal lock housing between a first angular position so
as to dispose the latching unit at the latching position,
CA 02567191 2006-11-03
4
and a second angular position so as to dispose the latching
unit at the unlatching position. The first rotatable member
is disposed in the accommodating space in the internal lock
housing, is coupled to the manual operating member so as
to be co-rotatable therewith between the first and second
angular positions, and is provided with a first protrusion.
The second rotatable member is disposed in the accommodating
space in the internal lock housing, is mounted rotatably
on the internal lock housing, and is provided with a second
protrusion. The second rotatable member is rotatable
relative to the internal lock housing in a first rotational
direction such that the second protrusion pushes the first
protrusion so as to move the first rotatable member from
the first angular position to the second angular position,
and in a second rotational direction opposite to the first
rotational direction such that the second protrusion pushes
the first protrusion so as to move the first rotatable member
from the second angular position back to the first angular
position. The electric driving unit is mounted in the
accommodating space in the internal lock housing and is
operable so as to drive rotation of the second rotatable
member.
BRIEF DESCRIPTION OF THE DRAWINGS
Other features and advantages of the present
invention will become apparent in the following detailed
description of the preferred embodiment with reference
to the accompanying drawings, of which:
CA 02567191 2006-11-03
Figure 1 is an exploded perspective view of the
preferred embodiment of an electric door lock according
to the present invention;
Figure 2 is a fragmentary exploded perspective view
5 to illustrate first and second rotatable members of the
preferred embodiment;
Figures 3 to 5 are schematic views to illustrate
operation of the preferred embodiment in an automated
mode for moving a latching unit of the preferred
embodiment from an unlatching position to a latching
position; and
Figure 6 is a schematic view to illustrate engagement
between first and second protrusions of the preferred
embodiment during operation of the preferred embodiment
in the automated mode for moving the latching unit from
the latching position back to the unlatching position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to Figure 1, the preferred embodiment of
an electric door lock according to the present invention
is shown to include an internal lock housing 21, a
latching unit 6, a manual operating member 41, first
and second rotatable members 56, 55, and an electric
driving unit.
The electric door lock of this embodiment is mounted
on a door panel (not shown) that has opposite first and second
surfaces (not shown) , and is operable both in manual and
automated modes, in a manner that will be described
CA 02567191 2006-11-03
6
hereinafter.
The internal lock housing 21 is mounted on the first
surface of the door panel, and has a base wall 211, and
a surrounding wall 212 that extends from a periphery
of the base wall 211 of the internal lock housing 21
and that cooperates with the base wall 211 of the internal
lock housing 21 to define an accommodating space 213.
The base wall 211 of the internal lock housing 21 is
formed with a first mounting hole 214 that is in spatial
communication with the accommodating space 213 in the
internal lock housing 21 and that has a hole axis (A) .
The electric door lock further includes an external
lock housing 22 that is mounted on the second surface
of the door panel. In this embodiment, the external lock
housing 22 is formed with a second mounting hole 220
that is coaxial with the first mounting hole 214.
The electric door lock further includes internal and
external handle units 31, 32. The internal handle unit
31 is mounted rotatably on the internal lock housing
21, and is operable so as to rotate relative to the
internal lock housing 21. In this embodiment, the
internal handle unit 31 includes a hollow cylindrical
part 311 that extends rotatably into the accommodating
space 213 in the internal lock housing 21 through the
first mounting hole 214 in the base wall 211 of the
internal lock housing 21, and a handle 312 that is
connected to the cylindrical part 311 of the internal
CA 02567191 2006-11-03
7
handle unit 31. The external handle unit 32 is mounted
rotatably on the external lock housing 22, and is operable
so as to rotate relative to the external lock housing
22. In this embodiment, the external handle unit 32
includes a hollow cylindrical part 321 that extends into
the external lock housing 22 through the second mounting
hole 220 in the external lock housing 32, and a handle
322 that is connected to the cylindrical part 321 of
the external handle unit 32.
The latching unit 6 is disposed movably in the second
mounting hole 220 in the external lock housing 22, and
is movable relative to the external lock housing 22
between latching and unlatching positions. In
particular, the latching unit 6 includes a pair of
latching members 61. The second mounting hole 220 in
the external lock housing 22 is defined by a hole-defining
wall 221 that is formed with diametrically disposed
engaging grooves 222. The cylindrical part 321 of the
external handle unit 32 is formed with diametrically
opposite engaging holes 320. When the latching unit 6
is at the latching position, each of the latching members
61 of the latching unit 6 projects radially and outwardly
with respect to the hole axis (A) to thereby engage a
respective one of the engaging holes 320 in the
cylindrical part 321 of the external handle unit 32 and
a respective one of the engaging grooves 222 in the
hole-defining wall 221 of the external lock housing 22.
CA 02567191 2006-11-03
8
At this time, the external handle unit 32 is inoperable.
On the other hand, when the latching unit 6 is at the
unlatching position, each of the latching members 61
of the latching unit 6 retracts radially and inwardly
with respect to the hole axis (A) to thereby disengage
the respective one of the engaging holes 320 in the
cylindrical part 321 of the external handle unit 32 and
the respective one of the engaging grooves 222 in the
hole-defining wall 221 of the external lock housing 22.
At this time, the external handle unit 32 is operable.
It is noted that the internal handle unit 31 is
operable regardless of the position of the latching
members 61 of the latching unit 6.
The electric door lock further includes an operating
rod member 7 that extends through the latching members 61
of the latching unit 6 and that has opposite first and second
ends 71, 72. In this embodiment, the operating rod member
7 is rotatable relative to the internal and external lock
housings 21, 22 between a first angular position so as to
dispose the latching unit 6 at the latching position (see
Figure 5), and a second angular position so as to dispose
the latching unit 6 at the unlatching position (see Figure
3).
It is noted that, in this embodiment, the first and second
angular positions are angularly displaced by an angle of
90 degrees.
The manual operating member 41 is mounted rotatably on
CA 02567191 2006-11-03
9
the internal lock housing 21, and has a first end portion
412 that is disposed externally of the internal lock housing
21, and a second end portion 411 that extends into the
accommodating space 213 in the internal lock housing 21
through the cylindrical part 311 of the internal handle unit
31, and that is connected to the first end 71 of the operating
rod member 7 so as to be co-rotatable therewith between the
first and second angular positions.
The electric door lock further includes a lock member
42 that is disposed in the cylindrical part 321 of the external
handle unit 32, that extends into the external lock housing
22, and that is coupled to the second end 72 of the operating
rod member 7. In this embodiment, the lock member 42 is
operable so as to rotate the operating rod member 7 between
the first and second angular positions.
It is noted that the lock member 42 is operable with
the use of a key (not shown) that is inserted into a keyhole
420 thereof.
With further reference to Figure 2, the first rotatable
member 56 includes a ring portion 561 that is sleeved securely
on the second end portion 411 of the manual operating member
41 so as to be co-rotatable therewith between the first and
second angular positions. In particular, the ring portion
561 of the first rotatable member 56 is formed with a pair
of diametrically disposed engaging recesses 560. The second
end portion 411 of the manual operating member 41 is provided
with a pair of axially extending arms 415, each of which
CA 02567191 2006-11-03
engages a respective one of the engaging recesses 560 in
the ring portion 561 of the first rotatable member 56. In
this embodiment, the first rotatable member 56 is provided
with a first protrusion 562 that extends radially and
5 outwardly from the ring portion 561 of the first rotatable
member 56, that is semi-circular in cross-section, that is
made from a resilient material, and that has flat and round
portions 565, 569.
The second rotatable member 55 is disposed in the
10 accommodating space 213 in the internal lock housing 21,
is co-axially disposed around the second end portion 411
of the manual operating member 41, and is mounted rotatably
on the base wall 211 of the internal lock housing 21. In
this embodiment, the second rotatable member 55 is in the
form of a gear that is provided with a second protrusion
555 protruding axially toward the first rotatable member
56. In this embodiment, the second protrusion 555 has a
trapezoidal shape. The second rotatable member 55 is
rotatable relative to the internal lock housing 21 in a first
rotational direction such that the second protrusion 555
pushes the first protrusion 562 so as to move the first
rotatable member 56 from the first angular position to the
second angular position, and in asecond rotational direction
opposite to the first rotational direction such that the
second protrusion 555 pushes the first protrusion 562 so
as to move the first rotatable member 561 from the second
angular position back to the first angular position.
CA 02567191 2006-11-03
11
The electric driving unit 8 is mounted in the
accommodating space 213 in the internal lock housing 21,
and is operable so as to drive rotation of the second rotatable
member 55 in the first and second rotational directions.
In particular, the electric driving unit 8 includes a motor
81 that has a transmission shaft 811, a worm gear 82 that
is sleeved fixedly on the transmission shaft 811 of the motor
81, a first gear 83 that is mounted rotatably on the base
wall 211 of the internal lock housing 21 and that meshes
with the worm gear 82, and a second gear 84 that is connected
to and that co-rotates with the first gear 83, and that meshes
with the second rotatable member 55. In this embodiment,
the electric driving unit 8 may be operated using a remote
controller (not shown) , or a keypad 851 of a user input unit
85 (see Figure 1) that is mounted on the external lock housing
22.
The electric door lock further includes a switching unit
for deactivating the motor 81 of the electric driving unit
8 when the first rotatable member 56 has been moved from
one of the first and second angular positions to the other
of the first and second angular positions. In particular,
the switching unit includes a sensing element 571, such as
a micro-switch, and a pair of first and second actuators
563, 564. The sensing element 571 of the switching unit is
disposed in the external lock housing 22, is mounted on a
printed circuit board 57, is coupled electrically to the
motor 81 through the printed circuit board 57, and is operable
CA 02567191 2006-11-03
12
so as to deactivate the motor 81 of the electric driving
unit 8 when actuated. The first actuator 563 of the switching
unit is provided on the first rotatable member 56, and is
angularly displaced from the first protrusion 562 by an angle
of 90 degrees. The second actuator 564 of the switching unit
is provided on the first rotatable member 56, and is angularly
displaced from the first actuator 563 by an angle of 90 degrees
and from the first protrusion 562 by an angle of 180 degrees.
In operation, at an initial position, in which the
latching unit 6 is at the unlatching position, operation
of the external handle unit 32 is enabled. At this time,
when it is desired to operate the electric door lock of this
invention in the manual mode using the manual operating
member 41 to disable operation of the external handle unit
32, the manual operating member 41 is rotated from the second
angular position to the first angular position. This results
in rotation of the operating rod member 7 from the second
angular position (see Figure 3) to the first angular position
(see Figure 5), and movement of the latching unit 6 from
the unlatching position to the latching position, thereby
disabling operation of the external handle unit 32. At this
time, when it is desired to operate the electric door lock
of this invention in the manual mode using the manual
operating member 41 to enable operation of the external
handle unit 32, the manual operating member 41 is rotated
from the first angular position back to the second angular
position. This results in rotation of the operating rod
CA 02567191 2006-11-03
13
member 7 from the first angular position back to the second
angular position, and movement of the latching unit 6 from
the latching position to the unlatching position, thereby
enabling operation of the external handle unit 32.
In addition, at the initial position, when it is desired
to operate the electric door lock of this invention in the
manual mode using the lock member 42 to disable operation
of the external handle unit 32, the lock member 42 is operated
with the use of the key to rotate the operating rod member
7 from the second angular position to the first angular
position. This results in movement of the latching unit 6
from the unlatching position to the latching position,
thereby disabling operation of the external handle unit 32.
At this time, when it is desired to operate the electric
door lock of this invention in the manual mode using the
lock member 42 to enable operation of the external handle
unit 32, the lock member 42 is operated with the use of the
key to rotate the operating rodmember 7 from the first angular
position to the second angular position. This results in
movement of the latching unit 6 from the latching position
to the unlatching position, thereby enabling operation of
the external handle unit 32.
Moreover, at the initial position, when it is desired
to operate the electric door lock of this invention in the
automated mode to disable operation of the external handle
unit 32, referring to Figure 3, the motor 81 of the electric
driving unit 8 is activated with the use of the remote
CA 02567191 2006-11-03
14
controller (not shown) or the keypad 851 of the user input
unit 85 (see Figure 1) . This results in rotation of the second
rotatable member 55 in the second rotational direction, as
indicated by the arrow (X), eventual engagement between the
first and second protrusions 562, 555, as best shown in Figure
4, co-rotation of the first rotatable member 56, the manual
operating member 41 (see Figure 1), and the operating rod
member 7 from the second angular position to the first angular
position, and movement of the latching unit 6 from the
unlatching position to the latching position, thereby
disabling operation of the external handle unit 32.
It is noted that when the first rotatable member 56 is
rotated to the first angular position, the second actuator
564 actuates the sensing element 571, as best shown in Figure
5, to thereby deactivate the motor 81 of the electric driving
unit 8. Due to the presence of inertial forces, the
transmission shaft 811 (see Figure 2) of the motor 81
continues to rotate momentarily, causing the second
rotatable member 55 to further rotate and the second
protrusion 555 to slide over the rounded portion 569 (see
Figure 2) of the first protrusion 562. As such, the second
protrusion 555 is prevented from obstructing path of the
first protrusion 562 during the operation of the electric
door lock of this invention in the manual mode.
Therafter, when it is desired to operate the electric
door lock of this invention in the automated mode to enable
operation of the external handle unit 32, referring to Figure
CA 02567191 2006-11-03
5, the motor 81 of the electric driving unit 8 is activated
with the use of the remote controller (not shown) or the
keypad 851 of the user input unit (see Figure 1) . This results
in rotation of the second rotatable member 55 in the first
5 rotational direction, as indicated by the arrow (Y),eventual
engagement between the first and second protrusions 562,
555, as best shown in Figure 6, co-rotation of the first
rotatable member 56, the manual operating member 41 (see
Figure 1), and the operating rod member 7 from the second
10 angular position back to the first angular position, and
movement of the latching unit 6 from the latching position
back to the unlatching position, thereby enabling operation
of the external handle unit 32.
It is noted that when the first rotatable member 56 is
15 rotated back to the second angular position, the first
actuator 563 actuates the sensing element 571, as best shown
in Figure 3, to thereby deactivate the motor 81 of the electric
driving unit 8. Due to the presence of the aforementioned
inertial forces, the transmission shaft 811 (see Figure 2)
of the motor 81 continues to rotate momentarily, causing
the second rotatable member 55 to further rotate and the
second protrusion 555 to slide over the rounded portion 569
(see Figure 2) of the first protrusion 562. As such, the
second protrusion 555 is prevented from obstructing the path
of the first protrusion 562 during the operation of the
electric door lock of this invention in the manual mode.
While the present invention has been described in
CA 02567191 2012-02-29
/ w
16
connection with what is considered the most practical
and preferred embodiment, it is understood that the scope
of the claims should not be limited by the preferred
embodiments but should be given the broadest
interpretation consistent with the description as a
whole.
