Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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MORTISE LOCK
FIELD OF THE INVENTION
The present invention relates generally to mortise locks and particularly to a
mortise lock with multiple bolts vvhich may be actuated either by a key or by
a door handle,
:c and which includes a "quick-open'' feature, i.e., all the bolts and latches
of the mortise lock
may be moved into an unlocked position by a partial turn of an inside door
handle.
BACKGROUND OF THE INVENTION
Mortise locks, also known as rim locks, are well known locks set in a recess
at
an edge of a door and which includes latches or bolts which can be thrown into
a locking
1o engagement with recess formed in the door post.
Panic doors are well known doors which can be quickly opened in an
emergency situation, no matter if the door is locked or not, generally by
simply pushing an
elongate, horizontal, waist-high bar from the inner side of the door (i.e.,
the side inside the
building). This bar is mechanically linked to an override mechanism which
opens all bolts or
15 latches of the door, no matter if they were previously locked or unlocked.
It is however not known to fashion a mortise lock with multiple bolts and/or
latches which may be actuated either by a key or by a door handle, and which
includes a door-
handle-actuated, quick-open feature, i.e., the equivalent ofthe panic door
function.
SUMMARY OF THE INVENTION
2o The present invention seeks to provide a mortise lock with multiple bolts
and/or
latches which may be actuated either by a key or by a door handle, and which
includes a door-
handle-actuated quick-open feature. The lock of the present invention is
particularly suitable
for rooms of hotels, motels, office buildings, school buildings, dormitories,
classrooms, public
restrooms, and the like.
25 There is thus provided in accordance with a preferred embodiment of the
present invention a mortise lock including a mortise lock case which houses a
locking
mechanism actuable by a key-operated lock cylinder, and actuable by a handle
which engages a
bolt follower in operative connection with the locking mechanism, and a
plurality of locking
bolts arranged for protruding outwards of the case and wherein the handle is
operatively linked
3o to the plurality of locking bolts by a linkage wherein the plurality of
locking bolts are actuable
into an unlocked position by suitable rotation of the handle independently of
whether or not the
mortise lock is locked by the key-operated lock cylinder.
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In accordance with a preferred embodiment of the present invention the handle
is selectively decouplable from at least one of the plurality of locking
bolts, wherein when the
handle is not coupled to the at least one of the plurality of locking bolts,
the at least one of the
plurality of locking bolts is actuable into the unlocked position only by
operation of the key-
operated lock cylinder.
Further in accordance with a preferred embodiment of the present invention the
handle is selectively decouplable from at least one of the plurality of
locking bolts without
disassembling the case.
Still further in accordance with a preferred embodiment of the present
invention
to the plurality of locking bolts are selectably couplable to and decouplable
from th.e locking
mechanism without disassembling the case.
Additionally in accordance with a preferred embodiment of the present
invention the locking bolts are modularly installable in the case without
disassembling the case.
In accordance with a preferred embodiment of the present invention the
1 t. plurality of locking bolts includes a latch bolt, a bolt and a dead bolt
latch which are configured
to protrude from a faceplate of the case, at least one first locking bolt
arranged to move
generally vertically, and at least one second locking bolt arranged to move
generally
horizontally.
Further in accordance with a preferred embodiment of the present invention the
2U lock includes a toggle which is mechanically linked to the bolt follower,
wherein suitable
rotation of the toggle selectively couples or decouples the bolt follower from
the locking
mechanism.
In accordance with a preferred embodiment of the present invention a pair of
lock cylinders are mounted on opposite sides of the mortise lock, each lock
cylinder including
2°~ a pin tumbler rotatably mounted in a bore formed in the lock
cylinder, a gear clutch slidingly
mounted in the bore of each lock cylinder, and a pair of link-hubs rotatably
mounted in the
lock case and operatively connected to the locking mechanism, each gear clutch
being adapted
to mate with a corresponding orne of the link-hubs, wherein the pin tumblers
and the gear
clutches are arranged such that a k;ey can be inserted into one of the pin
tumblers and push its
3o corresponding gear clutch to protrude from the lock cylinder and mate with
a corresponding
one of the link-hubs, while at the same time, another key can be inserted into
the other pin
tumbler and push its corresponding gear clutch to protrude from that lock
cylinder and mate
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with the other link-hub, such that rotation of either of the gear clutches
causes operation of the
locking mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be understood and appreciated more fully from the
following detailed description, taken in conjunction with the drawings in
which:
Fig. 1 is a simplified pictorial illustration of a mortise lock constructed
and
operative in accordance with a prel°erred embodiment of the present
invention;
Figs. 2 and 3 are simplified pictorial and plan view illustrations,
respectively, of
the inner locking mechanisms of the mortise lock of Fig. 1, the case of the
lack being
to illustrated with its cover removed;
Fig. 4 is a simplified plan view illustration of the mortise lock of Fig. 1,
in an
unlocked orientation after having partially turned the inner door handle so as
to implement the
quick-open feature of the mortise lock;
Fig. 5 is a simplified, enlarged pictorial illustration of a portion of the
mortise
lock of Fig. 1;
Fig. 6 is a simpliiued sectional illustration of a linking mechanism which
selectively actuates the quick-opera feature of the mortise lock of Fig. 1 in
accordance with a
preferred embodiment of the present invention, taken along lines VI-VI in Fig.
3;
Fig. 7 is a simplified exploded illustration of a pair of lock cylinders
mounted on
opposite sides of the mortise lock: of Fig. 1 with a clutch mechanism linking
therebetween,
constructed and operative in accordance with a preferred embodiment of the
present invention;
Figs. 8A and 8B are. simplified pictorial illustrations of one of the lock
cylinders
of Fig. 7, respectively before and ai3er inserting a key into a keyway thereof
Fig. 9 is a simplified front view of the lock cylinders of Fig. 7;
Fig. 10 is a simplified sectional illustration of the lock cylinders of Fig.
7, taken
along lines X-X in Fig. 9;
Fig. 11 is a simplified side view of the lock cylinders of Fig. 7; and
Figs. 12, 13 and 14 are simplified front-view, sectional and perspective
illustrations, respectively, of a link-hub and spur gear used with the lock
cylinders of Fig. 7.
3o DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
Reference is now made to Fig. 1 which illustrates a mortise lock 10
constructed
and operative in accordance with a preferred embodiment of the present
invention.
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Mortise lock 10 preferably includes a case 12 which houses a cocking
mechanism actuable by a key-operated lock cylinder 14, or by a handle 16 which
engages a
generally square spindle hole 18 of a bolt follower 19 (seen in Figs. 2 and
3). The details of the
locking mechanism and operation thereof by lock cylinder 14 and handle 16 are
described
herein below. Mortise lock 10 is preferably a multiple bolt lock, i.e., it
comprises a plurality of
locking bolts and/or latches. Although any number of locking bolts or latches
may be employed
in the present invention, in the illustrated embodiment mortise lock 10
includes a latch bolt 20
having an auxiliary latch 22, a rectangular bolt 24, and a dead bolt latch 26
which are
configured to protrude from a fac;eplate 28. In addition, the illustrated
embodiment includes
to two locking bolts 30 and 32 arranged to move vertically in the sense of an
upright door, and a
locking bolt 34 arranged to move horizontally in the sense of an upright door.
Lacking bolts
20, 24, 30, 32 and 34 can engage a variety of locking hardware installed in a
door and which
are used to lock the door, such Inardware being very well known in the art, so
no further
description is necessary for the skilled artisan.
15 Mortise lock 10 is preferably provided with two handles 16 one on each side
of
a door (not shown). As is well known in the art, the handle on the inner side
of the door (i.e.,
the side inside a building) is typically movable to actuate the locking
mechanism of the door,
whereas the handle on the outer side of the door (i.e., the side outside the
building) may be
movable or non-movable, depending on the particular application. In the
present invention, the
20 outside handle is selectively movable or non-movable, the selection being
accomplished by
means of a toggle 36 which is mechanically linked to bolt follower 19. Toggle
36 acts like a
clutch: by suitable rotation of toggle 36, bolt follower 19 is either coupled
or decoupled from
the locking mechanism, as is further described hereinbelow with reference to
Fig. 5.
Reference is now made to Figs. 2, 3 and 4 which illustrate the; locking
25 mechanism of mortise lock 10. The locking mechanism preferably includes a
gear wheel 38
selectively linked, as is described hereinbelow, with a toothed bolt-throw
wheel 40. Gear wheel
38 is preferably generally coaxial v~ith bolt-throw wheel 40. Bolt-throw wheel
40 meshes with
a spur gear 42 (Figs. 2 and 4) which is rotated by suitable rotation of lock
cylinder 14. (Lock
cylinder 14 is omitted for clarity in Figs. 2 and 4 to expose spur gear 42.)
For each locking bolt
30 24, 30, 32 and 34, bolt-throw whe:ei 40 has a radial groove 44 formed
therein which receives
therein a pin 46 attached to a corresponding one of locking bolts 24, 30, 32
and 34. Upon
rotation of pinion gear 42 in the direction of an arrow 48 (Fig. 4), bolt-
throw wheel 40 is
caused to rotate in the direction of an arrow 50, thereby causing pins 46 to
mave radially
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inwards in grooves 44 and bringing locking bolts 24, 30, 32 and 34 into an
unlocked position
shown in Fig. 4. Thus, locking bolts 24, 30, 32 and 34 are all actuable by the
key-operated lock
cylinder 14.
It is a particular feature of the present invention that locking bolts 24, 30,
32
:i and 34 are operatively engaged with the remainder of the locking mechanism
of mortise lock
in a modular manner, i.e., the: locking bolts are modularly installable in
case 12 without
disassembling case 12. Any number of the locking bolts may be installed in
lock 10 and other
locking bolts omitted, if desired. l~~loreover, locking bolts 24, 30, 32 and
34 may be selectably
coupled to or decoupled from the remainder of the locking mechanism without
disassembling
to case 12. These features are achieved by simply removing pins 46 which
attach the locking bolts
to bolt-throw wheel 40, pins 46 being accessible via access holes either on
the front or rear
face of case 12. In addition, after removal of a particular pin 46, any of the
locking bolts can be
reinstalled in case 12 at a different: orientation. For example, the positions
of the locking bolts
can be interchanged, or the lockinE; bolts can be inverted to face a different
side of case 12.
1~~ The actuation of latch bolt 20 and auxiliary latch 22 by means of lock
cylinder
14 is now described. Latch bolt 20 and auxiliary latch 22 are preferably
attached to a support
member 52 spring-loaded by means of a spring 54 (Fig. 3). Support member 52
has a notch 56
formed therein which engages a tongue 58 of a latch lever 60. A pair of pins
62 and 64 are
fixedly attached to latch lever 60. lPin 62 plays a role in actuation of latch
bolt 20 and auxiliary
2C~ latch 22 as is described in the following paragraph. The significance of
pin 64 is in the
operation of dead bolt latch 26 as is described further hereinbelow. Latch
lever 60 is pivoted
about a pivot 65.
Reference is now additionally made to Fig. 5. Bolt-throw wheel 40 has a
hooked recess 66 formed therein, configured to "snare", i.e., engage pin 62.
Rotation of spur
25 gear 42 in the direction of arrow ~48 causes bolt-throw wheel 40 to rotate
in the direction of
arrow S0, thereby causing hooked recess 66 to engage pin 62. Hooked recess 66
abutting
against and moving pin 62 causes latch lever 60 to swing generally in the
direction of an arrow
68 (Fig. 3) about pivot 65, thereby moving support member 52 also generally in
the direction
of arrow 68. Since notch 56 of support member 52 engages tongue 58 of latch
lever 60, the
3C~ movement of support member 52 brings latch bolt 20 and auxiliary latch 22
inside case 12 into
an unlocked position shown in Fig. 4. Thus, latch bolt 20 and auxiliary latch
22 are actuabie by
the key-operated lock cylinder 14.
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The operation of dead bolt latch 26 is now described with particular reference
to Fig. 5. Dead bolt latch 26 preferably includes a tongue 70, which in the
position illustrated
in Fig. 5 abuts against an arresting lever 72 at a face 74 thereof. Dead bolt
latch 26 is
preferably biased by a biasing device such as a flat spring 75. Arresting
lever 72 is pivoted
about a pivot 76, and includes a .copping face 78. When tongue 70 abuts
against face 74 of
arresting lever 72, arresting lever i'2 is pivoted such that pin 64 does not
abut against stopping
face 78, as shown in Fig. 5. In this position, face 74 of arresting lever 72
is biased against
tongue 70 by a biasing device such as a spring 80.
When dead bolt latch 26 is moved inwards in the direction of an arrow 82 (the
to position shown in Fig. 4), spring tongue 70 slips off face 74 and spring 80
urges arresting lever
70 to pivot in the direction of an arrow 84, whereupon stopping face 78 swings
to a position Q
(shown in phantom lines in Fig. 5) abutting a flat face of pin 64. In this
position, since pin 64
cannot move past stopping face 7i3 of arresting lever 72, pin 62 cannot be
moved by hooked
recess 66 of bolt-throw wheel 40. Therefore, latch lever 60 cannot move in the
direction of
arrow 68 (Fig. 3), and latch bolt 20 and auxiliary latch 22 cannot be
externally pushed into the
unlocked position shown in Fig. 4, thus achieving the dead bolt function.
The dead bolt function can be negated by turning spur gear 42 with key-
operated lock cylinder 14 as is noun described. Arresting lever 72 is
preferably provided with a
pin 73 which extends towards bolt-throw wheel 40. Bolt-throw wheel 40 is
formed with a cam
surface 71 which extends radially outwards slightly from the general perimeter
of wheel 40.
Upon rotation of spur gear 42 with key-operated lock cylinder 14, bolt-throw
wheel 40 turns
in the direction of arrow 50. Bolt-throw wheel 40 is configured such that
before hooked recess
66 abuts against pin 62, cam surface 71 pushes against pin 73, thereby causing
arresting lever
to pivot about pivot 76, in the direction of an arrow 63, out of the position
Q so as to release
pin 64 and latch lever 60. This negates the dead bolt function. Now hooked
recess 66 can
engage pin 62 and move latch lever 60 to bring latch bolt 20 and auxiliary
latch 22 into the
unlocked position shown in Fig. 4.
It should be emphasized that key-operated lock cylinder 14 may be installed on
only one side of the door or alternatively can comprise a double cylinder
which is installed on
3o both sides of the door. The dead bolt function can be negated by
operational rotation of one or
both key-operated lock cylinders 1~4. The dead bolt function can also be
negated by turning
handle 16 as is described further hereinbelow. As is described below, the
ability of the handle
16 to negate the dead bolt function is selective, i.e., the user can select
whether the handle 16
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can negate or not negate the deadl bolt function. In the illustrated
embodiment, the option of
selectively negating the dead bolt function with handle 16 is provided on only
one side of the
door, but it is appreciated that the option can be provided for both sides of
the door. :However,
the handles on both sides of the door can always bring latch bolt 20 and
auxiliary latch 22 into
the unlocked position shown in Fig;. 4.
Fig. 5 also illustrates the mechanism associated with toggle 36. In the
position
illustrated in Fig. 5, a face 86 of toggle 36 is biased against a detent 88,
and toggle 36 is
pivoted about a pivot 90. Upon rotation of toggle 36 about pivot 90 in the
direction of an
arrow 92, another face 94 is brought against detent 88, thereby urging detent
88 generally in
to the direction of an arrow 96 against a toggle follower 98. Toggle follower
98 thereby moves in
the direction of arrow 96, causing a dog 100 of toggle follower 98 to engage a
correspondingly formed notch 10:? formed in bolt follower 19. Once dog 100
fixedly mates
with notch 102, bolt follower 19 cannot be rotated. In such a locked position,
handle 16 cannot
be rotated in order to perform any action related to the locking mechanism of
lock 10. Such an
orientation is generally used for the outside handle of the door. Conversely,
when handle 16 is
decoupled from bolt follower 19, i.e., when dog 100 is brought out of
engagement with notch
102 (the position illustrated in Fig. S), handle 16 can be rotated to operate
the locking
mechanism of lock 10.
The actuation of latch bolt 20 and auxiliary latch 22 by means of handle 16 is
2C~ now described. Bolt follower 19 includes a cam 104 which is arranged to
push against a latch
follower 106. Latch follower 106 is pivoted about a pivot 108 and includes a
toothed arm 110
which meshes with gear wheel 38. Latch follower 106 is preferably biased
against an inner
surface of case 12 by means of a biiasing device such as a spring 112. As can
be seen in Figs. 2,
3 and S, a pin 114 is fixed to an e:Ktreme end of toothed arm 110. In the
position illustrated in
24~ Fig. 5, pin 114 abuts against a surface of an inner cutout I 16 formed in
latch lever 60.
Upon rotation of handle 16 in the direction of an arrow 118 (Fig. 4), cam 104
pushes latch follower 106 generally in the direction of an arrow 120. This
causes pin 114 to
pivot latch lever 60 generally in the direction of arrow 68 (Fig. 3) about
pivot 65, thereby
moving support member 52 also generally in the direction of arrow 68. As
mentioned
30 previously, since notch 56 of support member 52 engages tongue 58 of latch
lever 60, the
movement of support member 52 brings latch bolt 20 and auxiliary latch 22 into
the unlocked
position shown in Fig. 4. Thus, latch bolt 20 and auxiliary latch 22 are
actuable by handle 16.
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In addition to Fig. 5, reference is now made to Fig. 6. Gear wheel 38 is
selectively linked with bolt-throw wheel 40 preferably by means of a pin 122.
Pin 122 radially
protrudes outwards from a threaded fastener, such as a set screw 124. Set
screw 124 is
threaded into a hub 125 about which bolt-throw wheel 40 is firmly mounted.
Gear wheel 38
has an arcuate groove 126 formed therein. Fig. 6 illustrates pin 122 in groove
126. By suitable
turning of set screw 124, pin 122; can be moved (downwards in the sense of
Fig. 6) out of
arcuate groove 126. When pin 122 is seated in groove 126, rotation of handle
16 in the
direction of arrow 118 causes cam 104 to push latch follower 106 generally in
the direction of
arrow 120, which in turn causes gear wheel 38 and bolt-throw wheel 40 to
rotate in the
1a direction of arrow 50. Bolt-throw wheel 40 turns together with gear wheel
38 because pin 122
abuts against groove 126, therelby coupling bolt-throw wheel 40 to gear wheel
38. As
mentioned above, the rotation of bolt-throw wheel 40 in the direction of arrow
50, causes pins
46 to move radially inwards in grooves 44 and bringing locking bolts 24, 30,
32 and 34 into the
unlocked position shown in Fig. 4. Thus, when pin 122 is seated in groove 126,
rotation of
handle 16 in the direction of arrovv 118 performs a quick-open function:
locking bolts 24, 30,
32 and 34, as well as latch bolt 20 and auxiliary latch 22, are all actuable
by partial rotation
(typically, but not necessarily, about 30°) handle 16, regardless of
being previously locked or
not.
When pin 122 is not seated in groove 126, bolt-throw wheel 40 is decoupled
2C~ from gear wheel 38. In this case, rotation of handle 16 in the direction
of arrow 118 does not
actuate locking bolts 24, 30, 32 and 34, but rather only actuates latch bolt
20 and auxiliary
latch 22.
Rotation of handle 16, when the quick-open feature is selected, also negates
the
dead bolt function of dead bolt latch 26 and arresting lever 72 as is now
described. Arresting
25. lever 72 is preferably provided with a tongue 77, which in the position
illustrated in Fig. 5,
contacts bolt follower 19. Rotation of bolt follower in the direction of arrow
118 (Fig. 4),
pushes tongue 77 and causes arresting lever 72 to pivot about pivot 76 in the
direction of
arrow 63 and out of the position (~ so as to release pin 64 and latch lever
60. This negates the
dead bolt function. Only after release of the dead bolt function, does
continued rotation of bolt
3U follower 19 by handle 16 bring pin I 14 against inner cutout 116 so as to
pivot latch lever 60
generally in the direction of arrow 68 (Fig. 3) about pivot 65, thereby moving
support member
52 also generally in the direction of arrow 68, thereby bringing latch bolt 20
and auxiliary latch
22 into the unlocked position shown in Fig. 4.
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As mentioned here~inabove, key-operated lock cylinder 14 may be installed on
only one side of the door or alternatively can comprise a double cylinder
which is installed on
both sides of the door. As a further alternative, lock cylinders may be
installed on both sides of
the door which enable operating lock 10 by inserting a key into one of the
lock cylinders,
:~ located on one side of the door, and turning the key to actuate latch bolt
20 and auxiliary latch
22, even if another key is inserted attd tttrrted in the lock cylinder ort the
other side of the
door. This feature, described hereinbelow with reference to Figs. 7-14, may be
particularly
useful for Iocks installed in public places, such as hotels, wherein it may be
desired to enter a
room even if the occupant of the room has inserted a key in the inner-side
lock and has even
to turned the key.
Reference is now made to Figs. 7-14 which illustrate a pair of lock cylinders
200 mounted on opposite sides of mortise lock 10 (illustrated in a simplistic
form for the sake
of clarity, although it is understand to be the same lock of Fig. 1 ),
constructed and operative in
accordance with a preferred embodiment of the present invention. Each lock
cylinder 200
l:i preferably includes a pin tumbler 202 rotatably mounted in a bore 204. A
gear clutch 206 is
slidingly mounted in bore 204 between an end of pin tumbler 202 and a cover
208 secured to
an end of lock cylinder 200. A pair of springs 210 are preferably mounted
between an end of
gear clutch 206 and cover 208, a:nd normally urge gear clutch 206 towards the
key insertion
end of pin tumbler 202. As seen in Fig. 8B, pin tumbler 202 and gear clutch
206 are; arranged
20 such that a key 212 can be inserted into pin tumbler 202 and push gear
clutch 206 against
springs 210, thereby sufficiently pushing gear clutch 206 to protrude from
lock cylinder 200.
Gear clutch 206, when protruding from lock cyiinder 200, can mate with a
correspondingly formed aperture :Z14 of a link-hub 216. Link-hub 216 is
attached to spur gear
42 (as seen best in Figs. 12-14) described hereinabove. When gear clutch 206
is mated with
2.5 link-hub 216, turning of gear clutch 206, by suitable turning of key 212
inserted in pin tumbler
202, turns spur gear 42 to operate lock 10 as described hereinabove. As seen
in Fig. 12, the
aperture 214 on one side of spur gear 42 is the mirror image of the aperture
214 on the
opposite side of spur gear 42.
Both link-hubs 21 ei are rotatably mounted in lock case 12, as seen in Fig. I
O
30 (one link-hub 216 being visible on the left side of lock 10 in Fig. 7). As
seen in Figs. 10 and 13,
a spring 218 is preferably mounted between the two link-hubs 216 which
normally distances
the two link-hubs 216 from each other. Both link-hubs 216 are preferably
mounted on a
common shaft 217 (Fig. 13).
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The operation of lock cylinders 200 is now described. Key 212 may be inserted
into one of the lock cylinders 200, thereby pushing gear clutch 206 to
protrude from that lock
cylinder 200, as can be seen in Fig. 8B. In this position, as seen in the
lower lock cylinder 200
of Fig. 10 (key 212 being omitted for clarity in Fig. 10), gear clutch 206
enters and mates with
its corresponding link-hub 216. Ke:y 212 can be turned to rotate link-hub 216
and spur gear 42
and operate lock 10. The other link-hub 216 (the upper one in Fig. 10) is
urged against the
gear clutch 206 of the opposite lock cylinder 200 (the upper one in Fig. 10)
by spring 218.
Since, as mentioned above, the apertures 214 are mirror images of each other,
upper link-hub
216 does not mate with gear clutch 206.
1o Even with the first key 212 inserted and turned in the lower lock cylinder
200, a
second key 212 can be inserted in the opposite cock cylinder 200 (the upper
one in Fig. 10). As
mentioned above, at this point, aperture 214 of the upper link-hub 216 is not
aligned for
mating with the upper gear clutch 206. However, key 212 can be turned to
rotate pin tumbler
202 of the upper lock cylinder 20t) so as to align upper gear clutch 206 with
aperture 214 of
the upper link-hub 216, at which point spring 218 urges upper link-hub 216
upwards in the
sense of Fig. 10, so that aperture :? 14 mates with upper gear clutch 206.
Once the upper link-
hub 216 is mated with the upper gear clutch 206, the second key can now turn
both link-hubs
216 and thus rotate spur gear 42 and operate lock 10, despite the presence of
the first key in
the upper lock cylinder 200.
2C~ It will be appreciated by persons skilled in the art that the present
invention is
not limited by what has been particularly shown and described hereinabove.
Rather the scope
of the present invention includes both combinations and subcombinations of the
features
described hereinabove as well as modifications and variations thereof which
would occur to a
person of skill in the art upon reading the foregoing description and which
are not in the prior
2~~ art.
