Technical Field of the Invention
[0001] The present invention relates to a lock, more precisely to an automatic door lock
with hook-shaped latches showing improved security characteristics.
Background of the Invention
[0002] Automatic locks are known for their reliability against user carelessness. An automatic
lock is by definition automatically locked irrespective of whether a user rotates
the lock cylinder. This is the essential prominent advantage over a regular lock.
Automatic locks normally require a trigger mechanism in order for actuating locking
mechanism. It involves use of a trigger bolt to contact an opposite surface to be
moved back in order for driving a set of mechanical elements connected such that latches
engage in lock panel slots. To this end, such an automatic lock operates by a trigger
latch activating or releasing a mechanical component connected to an actuator mechanism
for switching a plurality of latches between a locking and unlocking positions
[0003] Besides, locks offering high security characteristics, that is to say, locks with
hook-shaped dual latches engaging in suitable slots within the door frame are well-known
in the circles of security lock manufacturers. Those are especially advantageous in
that when fully locked, they simply provide multiple axes locking so as to withstand
both vertical and horizontal forces produced in association with burglary attempts.
[0004] Multiple patent literature references may be provided herein, all with hook-shaped
latches rotated by a set of actuator mechanism driven axles. Among others, one of
the patents/patent applications available to the public is the Italian patent ITTO20000226,
which is issued in the name of Tesio S.r.l. The same discloses hook-shaped latches
in the form of curvilinear projections interlocking with latch slots laid on the lock
panel. Said curvilinear latches are rotated by way of axles connected thereto. Rotation
of the axles by an actuation mechanism is realized by a movable element commanding
an arm incorporating suitable pivots rotating said axles and therefore said curvilinear
latches.
[0005] The disclosure in regard to the hook-shaped latches herein differs from the available
prior art in that it features a special arrangement designed to prevent burglary attempts
specifically aiming at rendering hook-shaped latches nonfunctional by damaging their
rotation mechanisms. Although locks with this type of latches are substantially advantageous
over a regular linear latch lock, they still incorporate certain vulnerabilities.
[0006] It is a well-known fact that various techniques are used for releasing a door lock
in burglary attempts. One of those techniques is to employ a perpetual screw or endless
screw, like that of a jack, a screw that is fixed so that it cannot move longitudinally
as it rotates. Accordingly, once fixed at two sides of the door frame at a position
parallel to the door surface, it remains stationary and forces the door frame to bend
toward hollow spaces within the frame. This can eventually bend the frame to the extent
that hook-shaped latches reach their limit strength and therefore either their hook
ends break through a line defining the outer part hook head or the pivoting pins on
which said curvilinear latches are rotatably mounted - and therewith also fixed to
the side sheet of the lock case- and the latch actuation pins guided on the latches
tend to advance in the frame direction by tearing said lock case side sheet throughout
the distance up to the panel on the lock side. In the latter case, it is probable
that said pivot axles and guided actuation pins get broken off.
[0007] In both cases, on the other hand, all security aspects of the door will practically
become nonfunctional since respectively either the latches will no more be engaging
in the slots on the frame side lock panel in the absence of the hooking portions or
they will no more be secured neither by pivot axles nor by guided actuation pins.
[0008] The lock case side walls and several individual components of lock hardware are typically
secured to each other within the case in several points. The pins on the rotation
axes of the hook latches are also secured to the sheet material side wall. This becomes
a serious drawback especially in the event of a burglary attempt as exemplified earlier.
The linear tension produced by the perpetual screw along the transversal axis of the
door in the direction of the door frame especially requires the hook latches to resist
against the outward force induced on the hook ends.
[0009] When burglary takes place, the hook ends are in a position interlocked with the slots
on the frame side lock panel. This latter is made of a strong material and will not
break off in most cases. As the perpetual screw rotates, however, it will tend to
bend outward and the slots on the panel along with the hook ends interlocked therewith
will be deformed to the extent that a gap will occur in between the lock side and
the frame side panels.
[0010] Break of the hook-shaped latches can be prevented and remedied by way of appropriate
material selection. On the other hand, with the assumption that the outer hook portions
of the hook latches can resist against breaking off due to appropriate material selection,
the break away force will then exert on the axles and on the guided hook latch actuation
pins. Upon breaking off of the pivoting pins, whose primary function is not retaining
the integrity of the system and resisting against outside forces but to constitute
the rotation center thereof, the hook latches will first lose contact with the case
side sheet and by a certain damage on the guided actuation pins, the latches will
practically be free and not anymore secured to the lock case.
[0011] As will be apparent in the proceeding parts, the present invention solves the specific
problem of automatic locks by making use of the lock panel, which is already made
of a strong material and which is suitable for resisting against forces that are to
cause movement of the latches outside their predetermined outermost limit positions.
[0012] Along with the above information in relation to the security features of the hook-shaped
latches according to the present invention, the same brings about an improved security
lock capable of automatic operation. This is provided by a set of elements allowing
full-locking of the lock mechanism upon insertion of a triggering latch so as to activate
respective elements in order for advancing the hook-shaped latches into locked position.
[0013] Automatic locking is arranged by a triggering element allowing an extension part
thereof to disengage from a slot on a longitudinal carrier plate, this latter being
operated by the door handle to oversee unlocking of the hook-shaped latches. Automatic
locking is triggered when said trigger element makes contact with the door frame lock
panel.
[0014] The present invention provides a high security automatic lock which can conventionally
be opened from outside by way of rotating a key thereof in the lock cylinder or from
inside by way of turning the handle. Automatic locks are known in the field for their
feature of eliminating risks arising from user carelessness to leave the door unlocked.
The present invention therefore provides an automatic lock with high security curvilinear
latches.
Objects of the Invention
[0015] Primary object of the present invention is to provide a trigger mechanism high security
door lock with hook-shaped latches, the outward movement of which is kept within a
predetermined range and can not be removed from the lock case.
[0016] Another object of the present invention is to provide a door lock with hook-shaped
latches, whose latches lock into the their corresponding positions automatically when
the door is closed and whose latches have reinforcement pins that transfer the load
incurred during an attempt to separate the latch from the casing of the lock onto
the door-side lock panel as well as onto the frame-side lock panel, whereby the tear
force on the rotational axle of the latches are reduced.
Summary of the Invention
[0017] The present invention proposes a trigger mechanism high security lock comprising
a two-direction sliding bolt, a trigger latch and a set of separate hook-shaped latches
in the form of curvilinear projections operating jointly in the manner to interlock
with suitable latch slots on the door frame. Automatic locking is arranged by a triggering
element allowing an extension part thereof to disengage from a slot on a carrier plate,
this latter being operated by the door handle to oversee unlocking of the hook-shaped
latches. According to the present invention, said curvilinear latches are provided
with a plurality of pins vertically projecting from the lateral surface thereof in
the manner to face either of the case side sheets. In case of an unauthorized attempt
to release the lock by bending the lock panel on the door frame outwardly so as to
cause the latches to move in the direction of the frame, the vertically projecting
pins within the inside of the case will abut against the lock panel on the lock side
and prevent further movement of said latches.
Brief Description of the Figures
[0018] Accompanying drawings are given solely for the purpose of exemplifying a locking
assembly whose advantages over prior art were outlined above and will be explained
in detail hereinafter: The scope of the present invention, which is explained with
reference to the drawings below, can not be limited to the disclosure of the drawings
that are given solely for the purpose of exemplifying.
[0019] Fig. 1 demonstrates a perspective upper view of the lock assembly according to the
present invention.
[0020] Fig. 2 demonstrates a perspective side view of the lock assembly according to the
present invention.
[0021] Fig. 3 demonstrates another perspective side view of the lock assembly according
to the present invention.
Detailed Description of the Invention
[0022] Referring now to the figures outlined above, the lock assembly in Fig. 1, generally
referred to as 11, comprises a plurality of latches (12, 13 and 14) movable relative
to said assembly (11) in the manner to engage in suitable slots on the lock panel
and last but not least a trigger latch (15) that activates or releases a carrier plate
(16) in contact with an actuator mechanism for switching said plurality of latches
(13, 14) between a locking and an unlocking positions.
[0023] The two-way lock bolt (12) according to the present invention is formed in the manner
to be mounted irrespective of the actual closing direction of the door, that is to
say, the need to arrange the inclined surface of the bolt considering the closing
direction of the door is eliminated. The two-direction symmetrical bolt consists of
two half-parts mounted in opposite directions. Hence, neither the closing direction
of the door nor the door side on which the lock is to be mounted will not be relevant
since both half-parts are suitable for allowing sufficient clearance for door closure
in any direction. Both half-parts are rotatably mounted in opposite directions on
axles on their bottom portions.
[0024] The two-direction bolt (12) extends into the lock case in the form of a rod with
a carrier plate blockage pin (17) thereon. The carrier plate (16), whose details will
be disclosed below, is the most essential element of the automatic operation. Said
carrier plate blockage pin (17), when full-locking is reached, presses on the lateral
surface of said carrier plate (16) and is therefore disallowed from moving back. This
ensures protection against one of the most popular types of burglary attempts made
in the manner to insert a solid, thin object such as a bank card, in between the door
and the door frame along the bolt in order for moving the same back in a door closed
without locking.
[0025] The carrier plate (16) according to the present invention extends longitudinally
along the lock mechanism. It incorporates means for activating said curvilinear latches
(13, 14) and is basically controlled by the handle hub from inside and by the lock
cylinder from outside to release the lock. An extension (18) of the handle slot integrated
thereto moves said plate (16) by means of a carrier plate control pin (19).
[0026] The automatic operation is triggered by way of said trigger latch (15) being advanced
back so as to release an upright extension (20) thereof. Said upright extension (20)
normally rests in a carrier plate blockage recess (21) on said carrier plate (16).
When the trigger latch (15) makes contact with the door frame lock panel during closure,
it is moved back since there exist no corresponding slot on the opposite frame panel
and therefore releases said upright extension (20) from said carrier plate blockage
recess (21), causing advance of the spring loaded carrier plate to drive said curvilinear
latches (13, 14).
[0027] The carrier plate (16) always tends to set the lock mechanism to the locking position.
This is achieved through a plurality of spring loaded structures. One of these, referred
to as 23, is secured to the lock case lateral surface so as to be compressed by the
carrier plate (16) by means of an extension part thereof. The carrier plate spring
(23) is compressed when the mechanism is unlocked and stretched when it is locked.
When the handle hub extension (18) drives said carrier plate (16) into the unlocked
position longitudinally in the direction of the two-direction bolt (12), said carrier
plate blockage pin (17) engages in a recess (24) on said carrier plate (16) and restricts
its movement in any direction, therefore keeping said carrier plate spring (23) in
its compressed position.
[0028] The carrier plate blockage pin (17) and the trigger latch upright extension (20),
respectively engaging in the recess 24 and in the recess 21 ensure that the carrier
plate (16) is temporarily fixed until the trigger latch (15) makes contact with the
opposite lock panel to release said carrier plate blockage pin (17) and said trigger
latch upright extension (20) to let the plate (16) move in the direction of said curvilinear
latches (13, 14) by the pre-loaded spring forces to drive said latches (13, 14).
[0029] Another spring mechanism, referred to as 25 according to the present invention, is
secured to the longitudinal lateral surface of the lock case so as to continuously
press on an extension of the handle hub so as to rotate the same in the reverse direction
to the unlocking direction thereof. The force exerted by the spring mechanism 25 along
with that of the spring 23 provides automatic locking of the carrier (16) upon initiation
of triggering.
[0030] According to the present invention, a set of separate hook-shaped latches (13, 14)
in the form of curvilinear projections operating reciprocally in an integral manner
are employed so as to interlock with a suitable latch slot laid on the frame side
lock panel. Said curvilinear latches (13, 14) are designed to be operated jointly
and to be rotating by way of axles (22) connected thereto. The hook-shaped latches
(13, 14) are conventionally designed to have a curvilinear side on the outer portion
of the head part, the latter extending inward in the form of a right-angled corner
and forming therein a space between two blocks. One of those blocks is actually the
head portion, which engages into the slot on the lock panel.
[0031] As for the curvilinear latches (13, 14), rotation of the axles (22) so as to effect
locking of the latches (13, 14) is realized by an actuation mechanism started by insertion
of a key into the keyhole in the manner to advance a rotatable element (not shown)
of the lock cylinder, the latter driving said carrier plate (16) to provide locking.
The function of a lock cylinder is apparent to the person in the art. Apart from conventional
lock cylinders, the cylinder hereof is in the form of a half-cylinder accessible only
from inside the house.
[0032] The actuator means for the latches (13, 14) is typically comprised of a linearly
guided unidirectionally sliding plate (26) with two gripping arms (27) extending to
the latches' (13, 14) rotation center (22).
[0033] The linearly guided unidirectionally sliding plate (26) is connected to the carrier
plate (16) by means of a plurality of pins (31, 32 and 33) that move back and forth
through channels located on said carrier plate (16) in order for driving said linearly
guided unidirectionally sliding plate (26). Those channels (34, 35 and 36) are arranged
such that two longitudinally extending channels (34, 36) accommodates pins 33 and
32 and the other channel (35), which is inclined with respect to both the longitudinal
axis of said carrier plate (16) and with respect to the longitudinal axis of said
linearly guided unidirectionally sliding plate (26), accommodates pin 31. Said pins
32 and 33 are additionally guided within two channels (only channel 37 shown, channel
38 not shown but referred to for clarity) extending perpendicular to said open-end
channel 36 and channel 34 on said linearly guided unidirectionally sliding plate (26).
[0034] Said channel 35 incorporates at its far end a curved end part (39) to accommodate
said pin 31 in order for temporarily holding it when the spring loaded structures
(23, 25) are compressed in locked position.
[0035] According to the present invention, the curvilinear lock bolts (13, 14) are designed
to provide a single-turn 90-degree displacement ensuring engagement position into
the panel slot in one turn. Turning of an appropriate key in the keyhole causes the
axles (22) and a couple of redirection pins (28) that are guided within the latches
(13, 14), to rotate said latches (13, 14) accordingly. Each of said pins (28) is driven
back and forth between two edges of a guiding channel (29), depending on the positions
during engaging and disengaging. Synchronous movement of said redirection pin (28)
together with said axle (22) leads to a full step 90-degree slip of the curvilinear
latches (13, 14) in a reciprocal manner. Each gripping arm (27) extending to each
latch (13, 14) comprises an open end recess in order for laterally receiving said
axles (22) whose bottom surfaces are secured to a suitable slot on at least one of
the lock case sidewalls. When fully locked, the axles (22) are fully encircled with
the exception of the recess's open end to limit the movement of the same.
[0036] Beside said recesses on each arm, a slot for vertically accommodating said redirection
pin (28), which is only allowed a limited linear movement within said guiding channel
(29), is located. Movement of this latter to move the latch (13, 14) is directly effected
by said gripping arm (27) since it is placed into both the gripping arm (27) slot
and the latch channel (29) coaxially. In the very beginning of the locking sequence,
each gripping arm (27) reciprocally advances to slip said redirection pins (28) to
the channel (29) limits and further advancing of the gripping arms (27) causes the
redirection pins (28) to carry said latches (13.14) around each rotation center (22)
to the full-locked position. Single turn 90-degree movement of the latches (13, 14)
is not possible without the advance of the redirection pins (28) to the outermost
limit position in the guiding channels (29). In other words, rotation is effected
by the redirection pins' (28) movement within the channels (29) inclined with regard
to the lock panel direction. The fact that the location of the rotation center (22)
is on the direction of the inclined channels (29), provides an effective single-turn
90-degree slip. An effective single step full rotation would not be possible in an
alternative design in which the rotation centers (22) are not directly located on
the channels' (29) longitudinal direction.
[0037] In an automatic lock, to avoid a burglary attempt of the type defined earlier, in
which an endless screw is used to bend the lock panel in the direction of the door
frame in the manner to load stress on the most critical security components such as
the redirection pins (28) and the axles (22), the present invention features a set
of special arrangements to keep the redirection pins (28) and the axles (22) away
from the induced force components. Accordingly, said curvilinear latches (13, 14)
are additionally provided with a plurality of pins (30) vertically projecting from
the lateral surfaces of their body portions that remain within the lock case in locked
position. In case of an unauthorized attempt to release the lock by bending the lock
panel on the door frame outwardly so as to cause the latches (13, 14) to move in the
direction of the frame, the vertically projecting pins within the inside of the case
will abut against the lock panel and stop displacement of said latches (13, 14).
[0038] The reinforcement pins (30) are the first barriers to contact the lock panel in any
attempt to slip said latches (13, 14) outwardly, that is, in the direction of the
door frame. Since they are longitudinally embedded in the latch (13, 14) body in a
secure manner with the head portions slightly running over the latch (13, 14) surfaces
in a manner to form a sufficient contact surface with the lock panel portion outside
the latching slot, letting the latter stop the entire latch (13, 14) body moving and
resisting against outward forces otherwise exerted on the redirection pins (28) and
the axles (22).
[0039] The reinforcement pins (30) are located substantially close to the lock panel considering
the locked position layout of the latches (13, 14). In other words, the distance of
the reinforcement pins (30) to the lock panel is smaller than the radius of the reinforcement
pin (30) itself. More precisely, the smallest distance between a point of the reinforcement
pins (30) and the lock panel is smaller than the radius of the reinforcement pin (30)
itself.
[0040] According to the present invention, reinforcement pins may also be installed on the
far end of the latch (13, 14) to the lock panel. Such pins projecting symmetrically
from both surfaces of a curvilinear latch (13, 14) will further delay removal of latch
(13, 14). In the country of the applicant, it is known that the risk for a burglar
to fully release a high security lock sharply decreases as the duration consumed by
a burglar in front of a single lock increases.
[0041] In a nutshell, the present invention proposes a locking assembly (11) comprising
a plurality of regular and curvilinear latches (12, 13 and 14) movable relative to
said assembly (11) in a manner to engage in suitable slots on a lock panel, a trigger
latch (15) that activates or releases a carrier plate (16), a handle hub in control
of said carrier plate (16) from the inside, a half-cylinder mechanism in control of
said carrier plate (16) from the outside, actuator mechanisms for actuating said regular
and curvilinear latches (12, 13 and 14) and transmission mechanisms transferring motion
to said plurality of latches (12, 13, and14), said curvilinear latches (13, 14) being
provided with at least one reinforcement pin (30) projecting from the lateral surfaces
of the curvilinear latch (13, 14) body portions remaining within the lock case in
locked position.
1. A locking assembly (11) comprising a plurality of curvilinear latches (13, 14) movable
relative to said assembly (11) in a manner to engage in corresponding slots on a lock
panel, a trigger latch (15) that activates or releases a carrier plate (16), a handle
hub in control of said carrier plate (16) from the inside, a half-cylinder mechanism
in control of said carrier plate (16) from the outside, actuator mechanisms for actuating
said regular and curvilinear latches (13, 14) and transmission mechanisms transferring
motion to said plurality of latches (13, 14) characterized in that;
said curvilinear latches (13, 14) are provided with at least one reinforcement pin
(30) projecting from the lateral surfaces of the curvilinear latch (13, 14) and leaning
onto the interior of the door-side panel when the door is closed.
2. A locking assembly (11) according to Claim 1 wherein said reinforcement pins (30)
are longitudinally embedded in the curvilinear latch (13, 14) body with the head portions
running over the latch (13, 14) surfaces in a manner to form a lateral contact surface
with the lock panel portion outside the latching slot.
3. A locking assembly (11) according to Claim 2 wherein said reinforcement pins (30)
are located substantially close to the lock panel with regard to the locked position
layout of the latches (13, 14).
4. A locking assembly (11) according to Claim 1 wherein the assembly further comprises
a latch (12) having two half-parts rotatably mounted in opposite directions on axles
on their bottom portions.
5. A locking assembly (11) according to Claim 4 wherein said latch (12) extends into
the lock case in the form of a rod with a carrier plate blockage pin (17) thereon,
pressing on the lateral surface of said carrier plate (16) to be disallowed from moving
back in locked position and engaging in a recess (24) in unlocked position.
6. A locking assembly (11) according to Claim 1 wherein said handle hub comprises an
extension (18) integrated thereto to move said plate (16) by means of a carrier plate
control pin (19)
7. A locking assembly (11) according to Claim 1 wherein said trigger latch (15) comprises
an upright extension (20) resting in a carrier plate blockage recess (21) in unlocked
position and releasing from said recess (21) when the trigger latch (15) makes contact
with the door frame lock panel during closure.
8. A locking assembly (11) according to Claim 1 wherein said lock assembly (11) comprises
a spring loaded structure (23) secured to the lock case lateral surface so as to be
compressed by said carrier plate (16).
9. A locking assembly (11) according to Claim 8 wherein said lock assembly comprises
another spring loaded structure (25) secured to the longitudinal lateral surface of
the lock case so as to continually press on the handle hub in order for rotating the
same in the reverse direction to the unlocking direction of said handle hub.
10. A locking assembly (11) according to Claim 1 wherein said transmission mechanism transferring
motion to said plurality of curvilinear latches (13, 14) comprises a linearly guided
unidirectionally sliding plate (26) connected to the carrier plate (16) by means of
a first and a second pin (respectively 33 and 32) moving back and forth through perpendicularly
arranged channels (36, 37 and 34, 38) respectively located on said carrier plate (16)
and on said linearly guided unidirectionally sliding plate (26).
11. A locking assembly (11) according to Claim 10 wherein said carrier plate (16) comprises
a pin 31 guided within a channel (35) inclined with respect to both the longitudinal
axis of said carrier plate (16) and with respect to the longitudinal axis of said
linearly guided unidirectionally sliding plate (26).
12. A locking assembly (11) according to Claim 11 wherein said channel 35 incorporates
at its far end a curved end part (39) to accommodate said pin 31 in order for temporarily
holding it when the spring loaded structures (23 ,25) are compressed in locked position.