GB2438491A

GB2438491A - Door entry prevention device with biased lock concealing device

Info

Publication number: GB2438491A
Application number: GB0709204A
Authority: GB
Inventors: Michael Joyce
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-05-15
Filing date: 2007-05-14
Publication date: 2007-11-28
Anticipated expiration: 2027-05-14
Also published as: GB0709204D0; GB2438491B

Abstract

A door entry prevention device for use in a door having a cylinder lock has a concealing device 25 moveable between first and second positions. The lock concealing device 25 is biased towards said second position, wherein, in use, the lock concealing device is retained in its first position by a part of the cylinder lock and is released and urged to its second position when said part of said cylinder lock is detached from the remainder of the lock. The device prevents unauthorised entry when part of the cylinder lock is detached by force. The lock concealing device may comprise a spring loaded sliding plate 25 mounted in housing 23. The housing 23 may be mounted on elongate plate 21. A tab or flap 53 may prevent the plate from returning into the housing. There is also described a door provided with a door entry prevention device.

Description

DOOR ENTRY PREVENTION

Field of the invention

This invention relates to closure entry prevention and in particular to devices for use with closures having cylinder locks. Reference will be made hereinafter to doors but it should be understood that the invention is applicable to other types of closures.

Background to the invention

Cylinder locks are now fitted universally to doors including doors made of hollow plastics sections. In such doors the cylinder lock typically extends from one side of the door to the other and, at least on the outside of the door, extends through a hole or escutcheon in a door handle plate and can be accessed by means of a key to open or lock the door.

Such an arrangement is vulnerable to forced entry by a burglar or other intruder. By : .. levering off the door plate, or in some other way, it is possible to get sufficient purchase :. on the protruding cylinder lock, by means of a suitable tool, to be able to break the outer portion of the lock away from the inner portion, the break occurring within the door in a ** :*20 central portion of the lock adjacent the position where the lock member extends laterally from the barrel of the cylinder lock. Once the lock barrel has been broken in this way it is possible to gain access to the lock member, release it from its locking position and thereby gain access to the building through the door.

Statements of the invention

According to the present invention there is provided a door entry prevention device for use in a door having a cylinder lock, the device comprising means for fixing the device to the door adjacent to the cylinder lock, mounting means having mounted thereon lock concealing means moveable between first and second positions relative to said mounting means, and means biasing the lock concealing means towards said second position, wherein, in use, the lock concealing means is retained in its first position by a part of the cylinder lock and is released and urged to its second position when said part of said cylinder lock is detached from the remainder of the lock.

Accordingly, the present invention provides an arrangement whereby, when the cylinder lock is broken in the manner described above, the concealing means will move to prevent access to the remainder of the lock.

Preferably the device has means for locking the concealing means into its second position once it has moved to that position.

Preferably the mounting means is a housing within which the concealing means is substantially accommodated when the concealing means is in its first position.

:. Preferably the biasing means are spring-biasing means, for instance, a pair of coil springs :s*::: 15 which are compressed when the concealing means is in its first position and which, when the concealing means is released so as to be able to move to the second position, exerts a biasing force on the concealing means in a direction towards the second position.

Preferably the means for fixing the device to the door is an elongate plate which may be * *20 secured to the outside of the door on a surface towards the door frame. S. * .

Preferably the lock concealing means is a substantially rectangular plate and the lock mounting means is a housing for accommodating said plate in its first position.

Preferably the housing defines a space for accommodating the plate and also defines two grooves located on opposite sides of the space for the plate, each of said grooves being for accommodating a respective one of said coil springs.

According to a further aspect of the invention the device is provided with a restraining member which is adapted to prevent the return of the lock concealing means from the second (actuated) position to the first (dormant) position. In one embodiment of the invention the restraining member may comprise a substantially central tab or flap. Said tab or flap is biased towards a restraining position, but held away from this position by the presence of the lock concealing means in the housing. Thus, when the device is actuated, e.g. by removal of the cylinder lock, the lock concealing means is urged out of the housing. The absence of the lock concealing means therefore allows the restraining member to move to a position where it lies in the return pathway of the lock concealing means, thus hindering or preventing the return of the lock concealing means into the housing.

In an especially preferred embodiment, the restraining member comprises a flap (hereinafter referred to a as a "letterbox flap"). The letterbox flap is positioned in a side wall of the housing and on the opposing side wall an aperture is present. In addition, the letterbox flap is dimensioned so that when the letterbox flap is in a restraining position, it will rest across its located sidewall and the opposing wall, i.e. the open ends of each of ** 15 the walls. Such an arrangement is advantageous in that, inter alia, if an attempt is made * *** to force the lock concealing means back into the housing, such movement of the lock concealing means will be prevented by the presence of the letterbox flap. Even excessive force will not dislodge the letterbox flap because such movement of the letterbox flap will be prevented since it will be pushed against the open ends of the walls of the 20 housing.

*..*** * * Preferably the housing includes a moveable latch member which retains the plate within the housing, said latch member including a release member accessible from the outside of the door and operable to release the latch member to allow the plate to move from a third position to the first position where it is restrained from further movement by the lock barrel.

The present invention also includes a lock assembly including the door entry prevention device of the invention.

Furthermore, the present invention also includes a door having a lock assembly of the invention.

Brief description of the drawings

The accompanying drawings are as follows: Figure 1 is a cross-section through a plastics door section showing a cylinder lock and the device of the present invention; Figure 2 is a perspective view of a device in accordance with the present invention suitable for fitting to a door section such as that shown in Figure 1; Figure 3 is a perspective view of the device of Figure 2 but with the concealing means in its released position; Figure 4 shows the positioning of the device of Figure 2 relative to the barrel of the cylinder lock; S.

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:.. Figure 5 is a perspective view similar to that of Figure 4; * 20 S... S. * Figure 6 is a further perspective view, similar to that of Figure 5, but showing the concealing means in its released position; Figure 7 is a more detailed view of the device of Figure 2 with the housing lid removed; Figure 8 is a section on the line A of Figure 7; Figure 9 shows the device of Figure 7 without the springs and with the concealing means in its unreleased position; Figure 10 is a cross-Section of the device as shown in Figure 9; and Figures 12 (a) to (e) are representations of an additional embodiment of the invention in which a restraining tab or flap is replaced by a "letterbox" arrangement.

Detailed description of the invention

The invention will now be described, by way of example only and with reference to the accompany drawings.

Referring to Figure 1 of the accompanying drawings, a section of a plastics door I includes an outer web 3, an inner web 5 and a frame-engaging portion 7 fitted with a flexible seal element 9. Between frame-engaging portion 7 and outer web 3 is a frame facing web 11. Within the door section 1 is mounted a cylinder lock 13 having a lock barrel 15 which protrudes at its ends through webs 3 and 5 and provides, at these ends, keyholes (not shown). The ends of the cylinder lock may be located within the door *..:: 15 handle plates (not shown).

: *. Extending laterally from lock barrel 15 is a lock member 17 which is operable by the S...

:. keys to move from a first unlocked position to the second locked position where it : *. 20 engages within a recess located within the door frame (not shown).

With the cylinder lock protruding from the outside of the door, and perhaps with the door handle plate having been removed, it is possible for a would-be intruder to apply a wrench to the protruding end and obtain enough purchase to be able to break the lock barrel in two, the break occurring in the region of the lock member 17. Once this has been achieved, access to the lock member and the remainder of the lock is possible so that the door may be opened.

Also indicated in Figure 1 is a device in accordance with the present invention, referred to hereinafter as a cloaking device 19. The purpose of this device 19 is to operate automatically when the lock barrel is broken, in the manner described above, so as to prevent access to the remainder of the lock and thereby prevent opening of the door and entry into the building.

Referring now to Figures 2 and 6 of the accompanying drawings, the cloaking device 19 is shown in somewhat more detail. It includes an elongate plate 21 which may be screw fixed to the outer surface of web 11 once a rectangular hole has been provided in this web to allow a housing 23, attached to plate 21, to be passed through the hole to the position shown in Figure 1. As depicted in Figures 2 and 6, housing 23 is a fairly flat rectangular structure and, mounted within the housing, is a plate 25 which is spring-loaded by means of springs (not shown) located within the housing. These springs act to urge the plate from its position within the housing, as shown in Figure 2, to the position largely outside the housing as shown in Figure 3.

Figures 4 and 5 show arrangement with the lock barrel 15 in its normal, unbroken condition and with the plate 25 engaging the top of the barrel and being retained in its housing position thereby. By contrast, Figure 6 shows the arrangement with the lock barrel having been broken and detached from the lock so that the plate 25 has been spring propelled out of the housing 23 to conceal the remainder of the cylinder lock and thereby * : preventing access thereto and keeping the closed door in a secure condition.

* S Referring to Figures 7 to 11 of the accompany drawings, there is shown in more detail the device of the invention. The fixing plate 21 is provided with screw holes 27 and 29 by means of which the device may be affixed to the door in the manner described above.

Extending laterally from plate 21 is the housing 23 which comprises a base 31 and a similarly shaped lid 33. Between base 31 and lid 33 there is provided a space 35 which accommodates the plate 25. Housing 23 is closed top and bottom and along two edges 37 and 39 and also, by virtue of being attached to plate 19, along the edge opposite edge 39.

However, base 31 and lid 33 define an opening 41 which extends substantially the entire length of the remaining edge 43.

Plate 25 is a substantially rectangular shape and has an overall shape and size such that it fits snugly within the space 35 within housing 23. Plate 25 us provided at those corners which lie adjacent opening 41, when the plate is lodged within the housing, with outwardly and rearwardly extending tugs 45 to each of which is attached one end of a compression spring 47. The other end of each spring 47 is located on and attached to a lug 49 located within housing 23 and extending from edge 37 in a direction towards opening 41. As can be best seen in Figure 10, space 41 has enlarged portions 51 which provide grooves for accommodating the springs 47 and which ensure that the springs 47 are retained in their correct position within the housing 23.

Figure 9 shows the plate 23 in its first restrained position where, in use, it will bear against the top surface of the Lock barrel 15. Figure 7 shows the plate in its released position, largely out of the housing and thereby covering the space previously occupied : ... by the broken-off lock barrel and prevent access to the remainder of the lock. The * *** housing 23 is further provided with a central tab or flap 53 which, when unrestrained, * *, adopts the position shown in Figure 8. In this position it will be appreciated that it prevents plate 25 being moved, against the action of springs 47, back into the housing 23. *.S

When the plate 25 is located within the housing 23 it pushes tab 53 away from the position shown in Figure 8 toward the plane of the rest of the base 31 of the housing.

In order to load the device into position within the door, the plate 25 must, of course, be retained within the housing 23. This may be achieved by means of a detent (not shown) extending through a hole (not shown) in fixing plate 21, at least partially across the front of the plate 25 located within housing 23. When the device is fixed in position the detent may then be withdrawn by pulling it outwardly from the hole in plate 21. The plate will then move slightly in a direction out of the housing until its front edge surface comes to rest on the upper surface of the cylinder lock.

Referring to Figures 12 (a) to (e); Figure 12 (a) is a cross-sectional view of the device of the invention in the dormant position, thus the plate 25 of the lock concealing means is inside the housing 23 and the letterbox flap 54 is closed against the wall 55 of the housing 23 in which it is located. An aperture 56 in the opposing wall 57 to the letterbox flap 54 is also shown. Figure 12 (b) is a cross- sectional view of the device of the invention when it has been actuated and the plate 25 of the lock concealing means has been urged to its actuated position. The absence of the plate 25 of the lock concealing means in the housing 23 allows the letterbox flap 54 to be urged towards the inside of the housing 23.

Figure 12 (c) is a cross-sectional view of the device of the invention in the actuated position. It can be seen that the letterbox flap 54 lies across the pathway of the plate 25 of the lock concealing means and rests against the open ends 58 & 59 of the housing walls 55 & 60. In the aspect shown, force is being applied to urge the plate 25 of the lock concealing means back into the housing 23 and it can be seen that this is prevented because the plate 25 of the lock concealing means abuts the letterbox flap 54.

Figures 12 (d) and (e) illustrate alternative embodiments of devices of the invention S...

comprising a letterbox flap 54 according to the invention. * .*

The above described device may be made of any suitable material or materials. For instance, the housing 23 may be made of plastics and the plate 25 may be made of hardened steel. * 20 *SSS * *

Claims

Claims 1 A door entry prevention device for use in a door having a

cylinder lock, the device compilslng means for fixing the device to the door adjacent to the cylinder lock, mounting means having mounted thereon lock concealing means moveable between first and second positions relative to said mounting means, and means biasing the lock concealing means towards said second position, wherein, In use, the lock concealing means is retained in its first position by a part of the cylinder lock arid is released and urged to its second position when said part of said cylinder lock is detached from the remainder of the lock.

2. A device according to claim 1 and further including means for!ooking the concealing means into its second position once it has moved to that position. a. S. * *qS

*. 15 3. A device accordIng to claim I or claim 2, wherein the mounting means is a housing within which the concealing means I substantially accommodated when the concealing means Is In Its first position. a

4. A device according to any of the preceding claims, wherein the biasing means are : *: spring-biasing means.

*...SS * S 5. A device according to claim 4, wherein the spring-biased means are a pair of coil springs which are compressed when the concealing means is in its first position and which, when the concealing means is released so as to be able to move to the second positIon, exert a biasing fbrce on the concealing means in a direction towards the second position.

6. A device according to any of the preceding claims, wherein the means for fixing the device to the door is an elongate plate which may be secured to the outside of the door on a surface facing towards the door frame.

7. A device according to any of (he preceding claims, wherein the lock concealing means is a substantially rectangular plate and the lock mounting means is a housing for accommodating said plate in ha first position.

$ 8, A device according to claim 7, wherein the housing defines a space for accommodating said plate and also two grooves, located on opposite sides of the space for accommodating the plate, each of said grooves being for accommodating a respective coil spring.

9. A device according to claim 7 and claim 8, wherein the housing includes a movable latch member which retains the plate within the housing, said latch member including a release member accessible from the outside of the door and operable to release the latch member to allow the plate to move from a third position to the first position where it is restrained from turther movement by the lock barrel, **SS * S U..

10. A device according to claim 5 wherein the device is provided with a restraining member which Is adapted to prevent the return of the lock concealing means from a S..

second (actuated) position to a first (dormant) position. S. SI * S *

5...:: 20 Ii. A device according to claim 10 wherein the restraining member comprises a substantially central tab or flap.

12. A device according to claim 11 wherein the restraining member comprises a letterbox flap.

13, A lock assembly including a door entry prevent device as claimed in any of the preceding claims.

14. A door having a lock assembly according to claim 13.

15. A device according to claim I and substatniaIl as herein described.

16. A door entry device substantially as described herein with reftrence to the accompany drawings. ml ii * *.* I...

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