[0001] The present invention relates to lock mechanisms.
[0002] When using door or window arrangements, it is often a requirement to be able to prevent
the door or window from achieving a fully open position. This may be the case, for
example, when an occupier of premises wishes to see who is at the door but wishes
to prevent the visitor from forcing the door fully open and entering the premises.
[0003] One mechanism for achieving this effect includes securely attaching a first end of
a short safety chain to a doorframe and providing a receiving slot on the door in
to which a second end of the chain is detachably connected. The length of the chain
may be altered to vary the distance to which the door may be opened and may be completely
disconnected from the slot in order to open the door fully.
[0004] An alternative mechanism for preventing a door or window from opening fully comprises
the use of a safety lever instead of a chain for connecting the door to the doorframe.
A first end of the lever is pivotally secured to the doorframe often located close
to the central latch, and a second end, which has a slot therethrough is engaged by
a moveable member which is located inside the door. When the door is shut, the catch
lever hangs vertically and when the door is opened, the lever pivots upwards until
at a horizontal position where the member engaging the lever prevents further movement.
The length of the lever determines to what extent the door can be opened and the engaging
member may be disengaged from the lever allowing the door to open fully.
[0005] More elaborate lock mechanisms exist and comprise a moveable drive bar attached to
the side of the door where vertical movement of said drive bar results in the actuation
of latches, or the like, remote from the central latch. Such arrangements may also
be combined with the mechanisms for preventing a door or window from opening fully
as described above. A problem with such arrangements using a chain or catch lever
is that it can he relatively simple to break away a cover plate to enable unauthorised
movement of the drive bar.
[0006] With a view to solving or reducing the problem outlined above, it is an aim of the
embodiment of the present invention to provide a lock mechanism which displays improved
resistance to unauthorised entry.
[0007] According to the present invention, there is provided a lock mechanism comprising
a drive bar which operates at least one latch, and a locking means operable to cooperate
with said drive bar such that movement of the drive bar is prevented or suitably restricted.
The drive bar may be secured to a door or window by any means. The drive bar may be
connected along the vertical axis of the door or window by any means.
[0008] Preferably, the locking means prevents, in use, the movement of the drive bar in
any direction. The locking means may cooperate with the drive bar such that vertical
movement of the drive bar is prevented.
[0009] The drive bar may be provided with an aperture.
[0010] The aperture may be an elongate slot.
[0011] The locking means may be connected to the door or window. The locking means may comprise
a blocking member shaped to fill the elongate slot of the drive bar, when in a locking
position.
[0012] The blocking member may be box shaped.
[0013] The lock mechanism may further comprise a safety lever. The safety lever may be arranged
for pivotal attachment to a door or window frame. The safety lever may have an aperture
therein.
[0014] The blocking member may have a head which is engageable within the aperture of the
safety lever, when the lock mechanism is in an intermediate position, such that in
use the door or window can only open to a limited extent, controlled by the length
of the safety lever.
[0015] Means may be provided to operate the lock mechanism remotely, for example by means
of a hand held unit which can be operated to send a signal to a receiver of the lock
mechanism. This makes it possible for the safety lever to be engaged from outside
a building as well as inside, which is not possible with prior art devices.
[0016] Electrical components of the remote control device may be battery operated.
[0017] A solar panel device may be provided, for example for incorporation in glazing of
a door or window, the solar panel device being arranged to charge a battery.
[0018] The invention includes a locking means in combination with a drive bar as defined
above.
[0019] The invention also includes a window or door having at least one locking means in
combination with a drive bar as defined above.
[0020] For a better understanding of the invention, and to show how an embodiment of the
same may be carried in to effect, reference will now be made to the accompanying drawings
in which:
Figure 1 is a perspective view of a lock mechanism according to an embodiment of the
present invention;
Figure 2 is a perspective view of the lock mechanism according to the embodiment of
the invention in a first position;
Figure 3 is a perspective view of the lock mechanism according to the embodiment of
the present invention in a second position;
Figure 4 is a perspective view of a lock mechanism according to the embodiment of
the present invention in a third position;
Figure 5 is a perspective view of a further embodiment of lock mechanism according
to the invention, in a locked condition;
Figure 6 is a side view corresponding to Figure 5;
Figure 7 is a view similar to Figure 5 but with a face plate removed to show a drive
bar of the mechanism;
Figure 8 is a perspective view of the embodiment shown in Figure 5 but in an unlocked
condition;
Figure 9 is a perspective view of yet another embodiment of lock mechanism according
to the invention; and
Figure 10 is a perspective view of a still further embodiment of lock mechanism according
to the invention.
[0021] Figure 1 illustrates a lock mechanism generally shown as 2. The lock mechanism 2
comprises a safety lever 4 which has a first end 4a and second end 4b. The first end
4a is slidably connected to an elongate slot 6 of a fixing bar 8 which is secured
by securing means through apertures 10 to the inside of a door frame (not shown).
The second end 4b has an elongate aperture 12 and is of a suitable size to accommodate
a cylindrical head 14a of a body 14 which is generally box shaped and largely located
within a lock housing 16.
[0022] Figure 2 illustrates the lock mechanism 2 in a first position and shows the body
14 connected to the cylindrical head 14a by a neck region 14b. The head 14a passes
through an elongate aperture 20 in a drive bar 18 which, by means of vertical movement,
for example by rotation of a handle (not shown) is responsible for actuating other
latch mechanisms at remote locations from the lock mechanism. In the first position,
x
1, the surface of the cylinder head 14a sits flush against the side of the drive bar
18 The drive bar is free to move in a vertical direction and, assuming that all latch
mechanisms are in an unlocked configuration, the door is free to swing open.
[0023] Figure 3 illustrates the lock mechanism in a second position and shows the body 14
having moved to the right a distance, x
2, in a horizontal direction. The head 14a region has passed further through the aperture
20 in the drive bar 18 and now engages with the aperture 12 of the safety lever 4.
In the second position the drive bar is still free to move in a vertical direction
and, assuming that all latching mechanisms are in an unlocked configuration, the door
is free to swing open as the safety lever 4 pivots upwardly as shown in Figure 1 until
at a horizontal position when further movement is prevented. The length of the safety
lever 4 determines how far the door can open.
[0024] Figure 4 illustrates the lock mechanism in a third position and shows the cylinder
body having moved even further to the right a distance, x
3. The head 14a further engages the aperture 12 of the safety lever 4, however, now
the forwardly facing face of the body 14 also passes through the aperture 20 of the
drive bar 18 thereby preventing movement of the drive bar 18 in a vertical direction.
In such a configuration, the drive bar is unable to unlock the remote catches and
it is not possible to open the door at all.
[0025] Movement of the body 14 may be brought about by any desired locking device, such
as a cylinder lock, and because the box shaped body 14 completely blocks movement
of the drive bar 18 in the Figure 4 position, the door is secure even if an attempt
is made to force the lock.
[0026] The embodiment shown in Figures 5 to 8 has a housing 21 in which a locking hook 22
is pivotally mounted at 23. The hook 22 is pivotally connected at 24 to a plate 25
which is secured to a drive bar 26.
[0027] When the hook 22 is pivoted into the locked position shown in Figures 5, 6 and 7,
the hook engages in a door frame not shown. At the same time movement of the hook
causes the plate 25 and drive bar 26 to move, actuated locking at other points on
the door frame.
[0028] Figure 8 shows the locking hook 22 in the retract, unlocking position.
[0029] The hook projects through a slot in a face plate 27 which can be seen in Figures
5, 7 and 8.
[0030] In use, the hook 22 has a latching effect. However this embodiment also has security
locking means in the form of a retractable plunger 28.
[0031] Figure 7 shows the plunger 28 in a retracted position. In Figures 5 and 6, the plunger
28 is shown in the security position in which it has been extended to pass through
a first aperture 29 in the drive bar 26. After passing through the aperture 29, the
plunger then passes through an aperture 30 in the face plate 27. This effectively
locks the drive bar to the face plate 27. This effectively locks the drive bar to
the face plate so security is maintained even if an intruder manages to force the
hook 22 into an unlatched position.
[0032] Other forms of latches may be used instead of the hook 22.
[0033] The plunger 28 may be operated in any desired manner, for example using a solenoid.
[0034] Preferably the plunger can be operated remotely.
[0035] Manual means may be provided by means of which an authorised person within premises
can release the plunger 28 manually.
[0036] Even when the hook 22 is in the unlatched position shown in Figure 8, the plunger
28 may be extended through a second drive bar hole 31.
[0037] Figure 9 illustrates an embodiment in which a locking plunger 32 can be arranged
to project from a euro-groove 33 in part of the door frame 34.
[0038] The drive bar (not shown) is manually operated in a conventional manner using a handle
35. The plunger 32 is controlled by an electrical mechanism 36 mounted on the inside
of the door. The mechanism 36 contains a motor 37 for driving the plunger 32 in and
out, a receiver circuit 38, and a battery 39.
[0039] An authorised person has a remote control device which, when actuated, sends a signal
to the receiver circuit 38, operating the motor 37 to retract or extend the plunger
32.
[0040] A solar powered device may be provided to provide backup power to the battery 39.
[0041] A manual device may be provided for freeing the plunger 32 from within the premises
if necessary.
[0042] Figure 10 illustrates an embodiment similar in some respects to that shown in Figure
9, but in which a motor 40 is mounted within a housing 41. The motor 41 can be operated
to extend or retract a rectangular cross-section plunger 42.
[0043] Within the housing 41 there is also a rotatable member 43 having a tongue 44. If
the member 43 is rotated manually by a control knob (not visible in Figure 10) within
the premises, the tongue 44 acts on a projection 45 of the plunger 42 and retracts
the plunger. This acts as a safety override enabling the person to escape from the
premises in an emergency, even if there is a power failure.
[0044] The various embodiments of the invention can be applied to lock mechanisms and door
frames during original manufacture, or they may be retro-fitted to existing installations.
[0045] Although the lock mechanisms described above has been primarily designed for use
with windows or doors there may be circumstances in which the lock mechanism can be
used where any opening is provided with a cover.
[0046] The reader's attention is directed to all papers and documents which are filed concurrently
with or previous to this specification in connection with this application and which
are open to public inspection with this specification, and the contents of all such
papers and documents are incorporated herein by reference.
[0047] All of the features disclosed in this specification (including any accompanying claims,
abstract and drawings), and/or all of the steps of any method or process so disclosed,
may be combined in any combination, except combinations where at least some of such
features and/or steps are mutually exclusive.
[0048] Each feature disclosed in this specification (including any accompanying claims,
abstract and drawings), may be replaced by alternative features serving the same,
equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly
stated otherwise, each feature disclosed is one example only of a generic series of
equivalent or similar features.
[0049] The invention is not restricted to the details of the foregoing embodiment(s). The
invention extend to any novel one, or any novel combination, of the features disclosed
in this specification (including any accompanying claims, abstract and drawings),
or to any novel one, or any novel combination, of the steps of any method or process
so disclosed.
1. A lock mechanism comprising a drive bar which operates at least one latch, and a locking
means operable to cooperate with said drive bar such that movement of the drive bar
is prevented or suitably restricted.
2. A lock mechanism as claimed in Claim 1 wherein the locking means cooperates with the
drive bar such that, in use, vertical movement of the drive bar is prevented.
3. A lock mechanism as claimed in Claim 1 or 2, wherein the locking means prevents, in
use, the movement of the drive bar in any direction.
4. A lock mechanism as claimed in any preceding claim wherein means are provided to operate
the lock mechanism remotely.
5. A lock mechanism as claimed in Claim 4 wherein a hand held unit can be operated to
send a signal to a receiver of the lock mechanism.
6. A lock mechanism as claimed in Claim 4 or 5 wherein electrical components of the remote
control device are battery operated.
7. A lock mechanism as claimed in Claim 6 wherein a solar panel device is provided to
charge the battery.
8. A lock mechanism as claimed in any preceding claim wherein the lock mechanism further
comprises a safety lever.
9. A lock mechanism as claimed in Claim 8 wherein the safety lever is arranged for pivotal
attachment to a door or window frame.
10. A lock mechanism as claimed in any preceding claim wherein the drive bar is provided
with an aperture.
11. A lock mechanism as claimed in Claim 10 wherein the aperture is an elongate slot.
12. A lock mechanism as claimed in Claim 11 wherein the locking means comprises a blocking
member shaped to fill the elongate slot of the drive bar, when in a locking position.
13. A lock mechanism as claimed in Claim 12 wherein the blocking member may be box shaped.
14. A lock mechanism as claimed in Claim 12 wherein the blocking member has a cylindrical
head and a generally box shaped body.
15. A lock mechanism as claimed in any of Claims 12, 13 or 14 wherein the safety lever
has an aperture therein.
16. A lock mechanism as claimed in Claim 15 wherein the blocking member has a head which
is engageable within the aperture of the safety lever, when the lock mechanism is
in an intermediate position, such that in use the door or window can only open to
a limited extent, controlled by the length of the safety lever.
17. A lock mechanism as claimed in any preceding claim wherein the drive bar may be connected
along the vertical axis of the door or window by any means.
18. A lock mechanism comprising at least one latch, and a locking means to provide security
additional to that provided by the latch.
19. The lock mechanism as claimed in Claim 18, in which the locking means is operable
remotely.
20. A lock mechanism as claimed in Claim 18 or Claim 19, in which the locking means comprises
a locking member and operating means operable to move the locking member through an
aperture in a movable part of a latch mechanism and into a fixed member, thus preventing
authorised movement of the movable part of the latch mechanism.
21. A lock mechanism as claimed in any preceding claim wherein the locking means is connected
to a door or window.
22. A lock mechanism substantially as hereinbefore described with reference to the accompanying
drawings.
23. A window or door comprising a lock mechanism according to any preceding claim.