Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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DOOR LOCK WITH LARGE HANDLE
BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The present invention generally relates to a door lock, and more
particularly to a door lock with a large handle.
2. The Prior Arts
[00021 Currently available door locks having a large handle may have either of
the following two constructions. As shown in FIG. 6, one conventional type of
construction for the door lock may comprise an inner lock portion 17, an outer
lock
portion 1301 and a lock bolt 16. In this door lock structure, an outer key
button 7
and a large handle 134' is provided on the outer lock portion 1301. The large
handle
134' is securely assembled on the outer lock portion 1301. Through toothed
wheel
engagement, the outer key button 7 drives a drive shaft 1403 that passes
through a
cam 1610 of the lock bolt 16 to penetrate the inner lock portion 17. When the
outer
key button 7 is pushed down, the drive shaft 1403 is therefore driven in
rotation to
unlatch the door. While the lock bolt retracts into the lock bolt case, a
reposition
spring 172' in the inner lock portion 17 is loaded, increasing the required
pressure
action on the outer key button 7. This repeated loading of the reposition
spring 172'
during operation adversely reduces the life span of the door lock.
[00031 FIG. 7 is a perspective view of another conventional type of
construction
known for a door lock with a large handle. As shown, the door lock comprises
the
inner lock portion 17, the outer lock portion 1301 and the lock bolt 16. Two
drive
shafts 1401 and 1402 are provided on the outer lock portion 1301, and a lock
bolt
cam 1610 is provided on the lock bolt 16. During operation, the two drive
shafts
1401 and 1402 simultaneously insert into the lock bolt cam 1610 to drive the
lock
bolt 16 in movement. Driving the lock bolt 16 respectively from both inner and
outer
sides does not create interference. However, this type of construction still
has some
disadvantages. In particular, because two drive shafts are used to control the
operation of the lock bolt from both inner and outer sides, the length of the
two drive
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shafts usually needs to be adjusted when the thickness of the door varies to
ensure
that the two drive shafts properly insert into the lock bolt cam in a
simultaneous
manner. This may be a cumbersome task for the user.
SUMMARY OF THE INVENTION
(00041 The present invention provides a door lock with a large handle that is
simple in construction and convenient to operate.
(0005] The door lock includes an inner lock portion, an outer lock portion and
a
lock bolt, in which the outer lock portion has a large handle and a handle
base. The
outer lock portion mainly includes a transmission case having a drive shaft
hole; a
cover adapted to attach on the transmission case to form a receiving space, in
which
the cover has a through hole; an inner actuating plate and an outer actuating
plate
respectively disposed in the receiving space, in which the inner actuating
plate
comprises a first rib, a central region of the inner actuating pate has a row
of inner
teeth adapted to engage with an inner transmission wheel, a top surface of the
inner
transmission wheel has a first wedge-shaped protuberance, and the outer
actuating
plate comprises a second rib corresponding to the first rib, a central region
of the
outer actuating plate has a row of outer teeth adapted to engage with an outer
transmission wheel, a bottom surface of the outer transmission wheel has a
second
wedge-shaped protuberance that abuts against the first wedge-shaped
protuberance; a drive shaft having a front end securely fixed with a square
drive hole
of the inner lock portion, a rear end respectively passing through the through
hole of
the cover, a rotary axle hole of a rotary axle, a through hole of the outer
transmission
wheel, a through hole of the inner transmission wheel, and the drive shaft
hole of the
transmission case, in which the rear end of the drive shaft is securely fixed
with the
inner transmission wheel and is able to rotate through the through hole of the
outer
transmission wheel, and the outer transmission wheel comprises a mount hub
having a through hole corresponding to the rotary axle; and a key button
having a
drive surface that passes through the handle base and abuts against with a
lower
surface of the outer actuating plate.
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[0006] A separator plate is disposed between the inner actuating plate and the
outer actuating plate, a central region of the separator plate has a recess
through
which the inner actuating plate and the outer actuating plate are disposed,
and a
bottom of the separator plate includes a plurality of support lugs that
connect with a
bottom of the transmission case.
[0007] A lower end of the outer actuating plate comprises a tab extending
perpendicular to the outer actuating plate.
[0008] Each of two shoulder portions of the outer actuating plate respectively
comprises a stud, and a reposition spring is respectively disposed between
each
stud and a top inner wall of the transmission case.
[0009] The transmission case comprises at least two fastener catches, the
cover
comprises a plurality of slots corresponding to the fastener catches, the
fastener
catches adapted to insert through the slots to attach the cover on the
transmission
case.
[0010] The inner transmission wheel further comprises a hub provided with a
hole passing therethrough, and the rear end of the drive shaft has a
cylindrical
shape provided with a cut portion corresponding to the hole through the hub,
the cut
portion being adapted to pass through the hole of the hub.
[0011] The rear end of the drive shaft comprises a retainer slot, the rear end
passes through the inner transmission wheel and the drive shaft hole of the
transmission case, and being securely fixed via a fastener engaging with the
retainer
slot.
[0012] The through hole in the mount hub of the outer transmission wheel has a
square shape, and a cross-section of the rotary axle has a square shape
corresponding to the through hole in the mount hub.
[0013] The cover comprises at least two through holes, the handle base has a
plurality of threaded holes corresponding to the two through holes of the
cover, and
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fixing bolts pass the through holes in the cover and threadly engage with the
threaded holes in the handle base.
[0014] The cover comprises a plurality of matching holes corresponding to the
positioning holes of the lock bolt, support nuts have matching ends passing
through
the positioning holes of the lock bolt to fit in corresponding matched holes
on the
cover.
[0015] With the door lock of the present invention, the lock bolt can be
unlatched
respectively from the inner lock portion and outer lock portion to open the
door.
When the lock bolt is unlatched by actuating the key button from the outer
lock
portion, the reposition spring in the inner lock portion is not deformed,
which
improves the life span of the door lock and prevents the conventional problems
of
requiring an excessive force for opening the door owing to a deformation of
the
reposition spring. Additionally, unlike the conventional approach that uses
two
rotary axles respectively inserting into the lock bolt cam to drive the lock
bolt in
movement, the door lock according to the present invention simply uses one
rotary
axle to drive the lock bolt in movement. Therefore, when the thickness of the
door
varies, adjustment of the lengths of the two rotary axles is no longer
necessary.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The present invention will be apparent to those skilled in the art by
reading
the following detailed description of a preferred embodiment thereof, with
reference
to the attached drawings, in which:
[0017] FIG. 1 is an exploded view showing an outer lock portion of a door lock
having a large handle according to one embodiment of the present invention;
[0018] FIG. 1A is a perspective view showing an inner transmission wheel
provided in a transmission case of the door lock according to an embodiment of
the
present invention;
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[0019] FIG. I B is a perspective view showing an outer transmission wheel
provided in the transmission case of the door lock according to an embodiment
of
the present invention;
[0020] FIG. 1 C is a perspective view showing an opposite side of the outer
transmission wheel of FIG. 1 B;
[0021] FIG. 2 is a perspective view showing the door lock having the large
handle
according to one embodiment of the present invention;
[0022] FIG. 3A is a front view showing the outer lock portion of the door lock
when the key button is in a downwardly pushed position according to one
embodiment of the present invention;
[0023] FIG. 3B is a side view showing the outer lock portion of the door lock
when the key button is in a downwardly pushed position according to one
embodiment of the present invention;
[0024] FIG. 3C is a perspective view showing the outer lock portion of the
door
lock when the key button is in a downwardly pushed position according to one
embodiment of the present invention;
[0025] FIG. 4A is a front view showing the outer lock portion of the door lock
when the inner lock portion is turned clockwise according to one embodiment of
the
present invention;
[0026] FIG. 4B is a front view showing the outer lock portion of the door lock
without an outer actuating plate when the the inner lock portion is turned
clockwise
according to one embodiment of the present invention;
[0027] FIG. 4C is a perspective view showing the outer lock portion of the
door
lock when the inner lock portion is turned clockwise according to one
embodiment of
the present invention;
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[0028] FIG. 5A is a front view showing the outer lock portion of the door lock
when the inner lock portion is turned counterclockwise according to one
embodiment
of the present invention;
[0029] FIG. 5B is a front view showing the outer lock portion of the door lock
without the outer actuating plate when the inner lock portion is turned
counterclockwise according to one embodiment of the present invention;
[0030] FIG. 5C is a perspective view showing the outer lock portion of the
door
lock when the inner lock portion is turned counterclockwise according to one
embodiment of the present invention;
[0031] FIG. 6 is a perspective view of a conventional door lock having a large
handle; and
[0032] FIG. 7 is a perspective view of another conventional door lock having a
large handle.
DETAILED DESCRIPTION
[0033] The following description in conjunction with the accompanying drawings
set forth embodiments for achieving a door lock provided with a large handle.
[0034] As shown in FIGs. 1 and 2, a door lock with a large handle according to
one embodiment of the present invention comprises an outer lock portion 1301,
a
lock bolt 16, and an inner lock portion 17. The inner lock portion 17
comprises a
knob and a transmission element. The inner lock portion 17 has a square drive
hole
171' adapted to receive a front end of a drive shaft 14 of the outer lock
portion 1301.
When inserted into the square drive hole 171', the front end of the drive
shaft 14
needs to pass through a drive hole 1601 of the lock bolt 16. The drive shaft
14 and
square drive hole 171' have corresponding shapes so that when the knob
rotates,
the square drive hole 171' drives the drive shaft 14 in rotation.
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[0035] In addition, the inner lock portion 17 also includes a reposition
spring 172'
adapted to exert a restoring force after the knob has been rotated to cause
the knob
to recover its initial position.
[0036] At two sides of the drive hole 1601, the lock bolt 16 further includes
two
positioning holes 1602 in which support nuts 10 of the outer lock portion 1301
are
inserted to assemble the lock bolt 16.
[0037] The outer lock portion 1301 comprises a handle base 13 on which a large
handle 134' is fixed. A key button 7 is provided above the large handle 134'.
A rear
end of the key button 7 is located on an outer side of the handle base 13, and
a front
end of the key button 7 passes through a square hole 133' of the handle base
13. A
through hole 71' is provided on a central region of the key button 7, and
corresponding grooves 131' are also provided on the large handle 13. A
transverse
pin 8 passes through the through hole 71' and have two ends thereof
respectively
received in the grooves 131', so that the key button 7 can be pivoted upward
and
downward about the transverse pin 8. A front end of the key button 7 has a
drive
surface 72' that abuts against a lower surface of an outer actuating plate 3.
[0038] The handle base 13 is provided with at least two threaded holes 132' in
which fixing bolts 18 passing through threaded holes 93' of the cover 9 are
engaged
to securely fix the cover 9 on the handle base 13.
(0039] The outer lock portion 1301 further comprises the following elements.
[0040] A transmission case 12 has a rectangular slotted structure with four
bent
sides. A central portion of the transmission case 12 has a drive shaft hole
121'. The
four bent sides are provided with at least two fastener catches adapted to
pass
through attachment slots provided on the cover 9 to securely fix the cover 9.
As
shown in FIG. 1, two vertical sidewalls of the transmission case 12 are
provided with
four L-shaped fastener catches 122' that respectively pass through
corresponding
slots 92' on the cover 9 to fix the cover 9.
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[0041] The cover 9 attaches on the transmission case 12 to form a receiving
space. A central area of the cover 9 includes a through hole 94' located at a
position that corresponds to the drive shaft hole 121' on the transmission
case 12.
In addition, the cover 9 is provided with two matching holes 91' adapted to
fit with
matching portions 101' of the support nuts 10, which also pass through the
positioning holes 1602 of the lock bolt 16.
[0042] The receiving space formed by the cover 9 and the transmission case 12
also includes an inner actuating plate 5, an inner transmission wheel 4, the
outer
actuating plate 3, and outer transmission wheel 2. Each of these elements is
further
described below.
[0043] The inner actuating plate 5 comprises a row of inner teeth 51' adapted
to
engage with the inner transmission wheel 4. As shown in FIG. 1, the inner
actuating
plate 5 may have a U-shape, the row of inner teeth 51' being arranged on an
inner
edge of one side extension of the U-shape. A rib 52' also projects from a
surface of
the inner actuating plate 5 for abutting against a corresponding rib 32'
provided on
the outer actuating plate 3. When the inner actuating plate 5 moves upward,
the rib
52' abuts against the rib 32', thereby causing the outer actuating plate 3 to
also
move upward.
[0044] As shown in FIG. 1A, the inner transmission wheel 4 has a protruded
shape structure. One edge of the inner transmission wheel 4, having otherwise
a
generally rounded shape, is provided with inner teeth 41'. In addition, a
support hub
44' having a cylindrical shape protrudes from a surface of the inner
transmission
wheel 4. A central area of the support hub 44' includes a hole 42'.
Furthermore,
The surface of the inner transmission wheel 4 from which the support hub 44'
protrudes also comprises a protuberance 43'. The protuberance 43' has a wedged
shape that gradually increases in height along the circumference of the inner
transmission wheel 4. More particularly, when viewed from a side facing the
support
hub 44', the protuberance 43' has a shape that gradually increases in height
along
an counterclockwise direction.
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[0045] As shown in FIGs. 1 B and 1 C, the outer transmission wheel 2 also has
a
protruded shape structure. One edge of the outer transmission wheel 2, having
otherwise a generally rounded shape, is provided with outer teeth 21'. In
addition,
the outer transmission wheel 2 includes a mount hub 25' that has a central
area
provided with a through hole having a size corresponding to the outer contour
of a
rotary shaft 1. In this embodiment, the rotary shaft 1 has a hollow square
shape.
Therefore, the through hole on the mount hub 25' is formed as a corresponding
square hole 22'. Furthermore, a central area of the outer transmission wheel 2
also
has a through hole 23'. The through hole 23' has a circular shape and is
located on
an opposite side of the square hole 22'. On an opposite side of the mount hub
25',
the outer transmission wheel 2 includes a protuberance 24'. The protuberance
24'
has a wedged shape that gradually increases in height along the circumference
of
the outer transmission wheel 2. More particularly, when viewed from a side
facing
the mount hub 25', the protuberance 24' has a shape that gradually increases
in
height along a clockwise direction.
[0046] Referring to FIG. 1 again, a central region of the outer actuating
plate 3
includes a row of teeth, row of outer teeth 31', adapted to engage with the
outer
teeth 21' of the outer transmission wheel 2. As a result, when the outer
transmission
wheel 2 rotates, the outer actuating plate 3 will accordingly move upward or
downward. As described previously, the key button 7 when moved
upward/downward drives upward/downward movement of the outer actuating plate
3,
which causes the outer transmission wheel 2 to rotate either clockwise or
counterclockwise.
[0047] In this embodiment, a lower surface of the outer actuating plate 3 can
also
include a tab 33' arranged perpendicular to the body of the outer actuating
plate 3.
The drive surface 72' of the key button 7 can thereby abut against the tab
33', which
increases the contact surface area and improves work reliability.
[0048] The outer actuating plate 3 when being driven by the key button 7 moves
upward. Based on its own weight, the outer actuating plate 3 may also
reversely
move downward. However, relying on the sole weight for the downward movement
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cannot warranty the location and speed of the downward movement, which may
affect the operation of the door lock. Therefore, in this embodiment, two
shoulder
portions of the outer actuating plate 3 are respectively provided with a stud
34'.
When the outer actuating plate 3 is located in the receiving space formed by
the
cover 9 and transmission case 12, a reposition spring 6 placed between each
stud
34' and a top inner wall of the transmission case 12 can interact with the
outer
actuating plate 3 and cause it to quickly recover its initial position. In
this manner, a
correct operation of the door lock is ensured.
[0049] The outer lock portion 1301 further includes a drive shaft 14. A front
end
of the drive shaft 14 inserts into the square drive hole 171' of the inner
lock portion
17 to be secured therein. When the knob of the inner lock portion 17 rotates,
the
drive shaft 14 is driven in rotation. A rear end of the drive shaft 14 has a
cylindrical
shape that passes through the through hole 94' of the cover 9, a rotary axle
hole 12'
of the rotary shaft 1, the circular through hole 23' of the outer transmission
wheel 2,
the hole 42' of the inner transmission wheel 4, and drive shaft hole 121' on
the
transmission case 12. The cylindrical rear end of the drive shaft 14 passing
through
the rotary axle hole 12' and the circular through hole 23' of the outer
transmission
wheel 2 is enabled to freely rotate relative to these holes. However, the
cylindrical
rear end of the drive shaft 14 is securely mounted through the hole 42' of the
inner
transmission wheel 4 so that no rotation is enabled therebetween. Practically,
a
radial cut portion 141' may be provided on the rear end portion of the drive
shaft 14
corresponding to the hole 42'. The radial cut portion 141' engages in the hole
42' so
as to securely fix the drive shaft 14 with the inner transmission wheel 4.
[0050] In order to prevent accidental disengagement of the drive shaft 14, the
rear end of the drive shaft 14 further includes a retainer slot 142' that is
able to
secure with a fastener piece having a corresponding shape after the rear end
of the
drive shaft 14 is inserted through the inner transmission wheel 4 and the
drive shaft
hole 121' of the transmission case 12. The drive shaft 14 is thereby prevented
from
accidental disengagement.
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[0051] In the aforementioned door lock structure, a separator plate 11 is also
provided between the inner actuating plate 5 and the outer actuating plate 3.
The
separator plate 11 isolates the inner actuating plate 5 from the outer
actuating plate
3 to prevent undesirable interaction when the inner actuating plate 5 and
outer
actuating plate 3 are moving relative to each other, which would affect the
operation
of the door lock. A central area of the separator plate 11 is provided with a
recess
for receiving the inner transmission wheel 4 and outer transmission wheel 2.
In
addition, a bottom end of the separator plate 11 has lugs 112' that couple
with the
bottom of the transmission case 12 to securely fix the separator plate 11.
[0052] To achieve the present invention, embodiments for assembling the door
lock are described hereinafter.
[0053] Referring to FIGs. 1 and 2 again, for assembling the outer lock portion
1301, the transmission case 12 is first assembled. After the inner actuating
plate 5
and inner transmission wheel 4 in engagement are placed in the transmission
case
12, the separator plate 11 is then mounted over with the lugs 112' abutting
against
the bottom surface of the transmission case 12. To achieve a correct assembly,
movement of the inner actuating plate 5 and inner transmission wheel 4 must be
suitably permitted inside transmission case 12.
[0054] Next, the outer actuating plate 3 and outer transmission wheel 2 in
engagement are placed in the transmission case 12. At this stage, the outer
transmission wheel 2 is closely fit on the support hub 44' of the inner
transmission
wheel 4, the protuberance 24' engages with the protuberance 43', and the rib
32' on
the outer actuating plate 3 engages with the rib 52' of the inner actuating
plate 5.
[0055] The stud 34' on the outer actuating plate 3 abuts against the
reposition
spring 6, which has its opposite end connected with the inner wall of the
transmission case 12.
[0056] After the rotary shaft 1 is inserted in the square hole 22' of the
mount hub
25', the cylindrical rear end of the drive shaft 14 is passed through the
rotary axle
hole 12', the circular through hole 23' of the outer transmission wheel 2, and
the hole
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42' of the inner transmission wheel 4, respectively. The rear end portion of
the drive
shaft 14 provided with the retainer slot 142' then extends out of the drive
shaft hole
121' and is secured with a fastener element. At this stage, the cut portion
141' of
the drive shaft 14 fully inserts into the hole 42'.
[0057] Next, the support nuts 10 are secured on the cover 9 so that its
matching
portions 101' fit into their respective matching holes 91'. The cover 9 is
then put in
place over the transmission case 12, and the fastener catches 122' on the
transmission case 12 are passed through the corresponding slots 92' on the
cover 9
and are then bent to tightly press thereon. The assembly of the transmission
case
12 is thereby completed.
[0058] The key button 7 is inserted from the outer side into the square hole
133'
of the handle base 13. After the transverse pin 8 is passed from the interior
of the
handle base 13 through the through hole 71', the two ends of the transverse
pin 8
are respectively mounted in their corresponding grooves 131' on the handle
base 13,
which thereby securely mounts the key button 7.
[0059] Lastly, the above assembled transmission case is secured on the handle
base 13 using fixing bolts 18 engaging threaded holes 132' of the handle base
13.
At this stage, the tab 33' at the lower end of the outer actuating plate 3 is
in close
contact with the drive surface 72' at the front end of the key button 7. The
assembly
of the outer lock portion 1301 is thereby completed.
[0060] After the drive shaft 14 is mounted through the drive hole 1601 of the
lock
bolt 16, the two positioning holes 1602 of the lock bolt 16 are respectively
inserted
into the support nuts 10. The front end of the drive shaft 14 is then mounted
through
the square drive hole 171' of the inner lock portion 17, which thereby
completes the
assembly of the door lock.
[0061] Reference is now made to FIGs. 3A-3C, 4A-4C, and 5A-5C to describe
the operation of the door lock.
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[0062] FIGs. 3A, 3B and 3C show the door lock of the present invention having
the key button 7 in a downwardly pushed position. As shown, when the key
button 7
is pushed downward, the drive surface 72' interacts with the tab 33' to cause
the
outer actuating plate 3 to move upward. Consequently, the engagement between
the row of outer teeth 31' and the outer teeth 21' causes the outer
transmission
wheel 2 to rotate, and then via the square hole 22' causes the rotation of the
rotary
axle 1 to unlatch the door that can then be opened. It is noted that the rib
32' on the
outer actuating plate 3 when being mounted is located above the rib 52' of the
inner
actuating plate 5. Therefore, when the outer actuating plate 3 moves upward,
the
inner actuating plate 5 is prevented from moving upward. In other words, in
the
above operation, only the outer actuating plate 3, the outer transmission
wheel 2
and rotary axle 1 are moving, whereas the inner actuating plate 5, the inner
transmission wheel 4 and the drive shaft 14 remain stationary. In this manner,
when
the key button on the outer lock portion is actuated to open the door, the
reposition
spring 172' in the inner lock portion does not receive any external force,
which
advantageously increases the life span of the door lock. In addition, when the
outer
key button is actuated, problems related to excessive force for opening the
door due
to the action of the reposition spring 172' in the inner lock portion can be
prevented.
[0063] FIGs. 4A, 4B and 4C show the door lock of the present invention when
the
knob in the inner lock portion is turned clockwise. As shown, when the knob is
turned clockwise, the square drive hole 171' in the inner lock portion 17
drives the
drive shaft 14 in rotation. Because the rear end of the drive shaft 14 has a
cylindrical shape that can freely rotate through the through hole 23' of the
outer
transmission wheel 2, the rotating drive shaft 14 does not drive the outer
transmission wheel 2 in rotation. Moreover, as the cut portion 141' on the
rear end
of the drive shaft 14 engages with the hole 42' of the inner transmission
wheel 4, the
clockwise rotation of the drive shaft 14 also causes the inner transmission
wheel 4 to
rotate clockwise. As a result, owing to the engagement between the inner teeth
41'
of the inner transmission wheel 4 and the row of inner teeth 51' of the inner
actuating plate 5, the inner actuating plate 5 is caused to move upward.
Through
the contact between the rib 52' of the inner actuating plate 5 and the
corresponding
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rib 32' on the outer actuating plate 3, the outer actuating plate 3 is also
caused to
move upward. Lastly, the row of outer teeth 31' on the outer actuating plate 3
moves upward to cause the outer transmission wheel 2 to counterclockwise
rotate,
whereas the rotary axle 1 inserted through the square hole 22' of the outer
transmission wheel 2 also rotates counterclockwise. As a result, the lock bolt
is
caused to retract to unlatch the door.
[0064] FIGs. 5A, 5B and 5C show the door lock of the present invention when
the
knob in the inner lock portion is turned counterclockwise. As shown, when the
knob
is turned counterclockwise, the inner transmission wheel 4 connected with the
rear
end of the drive shaft 14 also rotates counterclockwise. Because the
protuberance
43' on the inner transmission wheel 4 and the protuberance 24' on the outer
transmission wheel 2 contacts with each other, the counterclockwise rotation
of the
inner transmission wheel 4 causes the protuberance 43' to apply an additional
pressing force on the protuberance 24', urging the outer transmission wheel 2
to
rotate counterclockwise. As a result, the rotary axle 1 inserted through the
square
hole of the outer transmission wheel also rotates counterclockwise and causes
the
lock bolt to retract, which unlatches the door.
[0065] With the door lock according to the present invention, the lock bolt
thus
can be unlatched respectively from the inner lock portion and outer lock
portion to
open the door. When the lock bolt is unlatched by actuating the key button
from the
outer lock portion, the reposition spring 172' in the inner lock portion is
not deformed,
which improves the life span of the door lock and prevents the conventional
problems of requiring an excessive force for opening the door owing to a
deformation of the reposition spring 172'. In addition, unlike the
conventional
approach that uses two rotary axles respectively inserting the lock bolt cam
to drive
the lock bolt in movement, the door lock according to the present invention
simply
uses one rotary axle to drive the lock bolt in movement. Therefore, when the
thickness of the door varies, adjustment of the length of the two rotary axles
is no
longer necessary.
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[00661 While the foregoing is directed to embodiments of the present
invention,
other and further embodiments of the invention may be devised without
departing
from the basic scope thereof, and the scope thereof is determined by the
claims that
follow.
