Lock protection device

Abstract

 The invention relates to a device (5) in the form of a guard for a cylinder lock mounted in a closure (1) such as a door or window for operation thereof. The device (5) projects forwardly of a major front face (3) of the closure (1), and has an outer boundary surface (6) which tapers away from the closure (1). The surface (6) is received in an aperture (4) in the closure (1) having a complementary taper. Thus it is difficult to apply a tool such as a wrench to the device (5), as the tool will not gain sufficient purchase to snap off the device (5). The cylinder is thereby protected from attack.
The device (5) has a flange (8) received in use in a rebate (2) of the closure (1) for mounting the device (5) in the closure (1).

Description

[0001] The invention relates to locks, particularly to locks known as Euro-cylinder locks, which have a specification equivalent to British Standard EN 1303.

[0002] Generally, the so-called Euro-cylinder locks have a substantially uniform keyhole-shaped cross-section. Other cross-sections such as oval or elliptical are possible. As will be appreciated, such cylinder locks usually include a row of differ pins and are generally key operable and are usually used in conjunction with a handle to open and close a closure such as a door or window, operation of the handle from a closed or locked condition of the closure to an open or unlocked condition being determined by the respective locked or unlocked state of the cylinder lock. The doors may be of any suitable material, such as wood, composite metal plastics such as uPVC, metal coated with plastic, or any other suitable material.

[0003] The handles referred to are usually mounted on a mounting plate. If such is removed, usually without authority by say a burglar, the cylinder of the lock can be exposed. It can then be engaged by a tool such as a mole grip or a "snapper" and broken off, or turned. In either event, the lock no longer prevents access to the door or window, and unauthorised access can be gained to a building in which the closure is mounted.

[0004] It is an object of the invention to seek to mitigate this disadvantage.

[0005] According to the invention there is provided a device for obviating damage to a cylinder lock in situ on a closure, comprising an outer boundary surface which in use is tapered away from the closure.

[0006] The device may suitably be a separate device which is adapted to receive a cylinder of the cylinder lock.

[0007] The device may alternatively comprise part of the cylinder of the lock.

[0008] Thus in this construction the device and cylinder lock comprise a single unit.

[0009] The single unit may be formed in one piece as by casting, moulding or machining.

[0010] In either embodiment, there may be a means by which the device may be secured in a closure.

[0011] In a suitable construction, the means may be a flange which may be adapted for securing to a closure.

[0012] It will be understood that the invention extends to embrace a closure, such as a door or window, in combination with a device as hereinbefore defined.

[0013] A device embodying the invention is hereinafter described, by way of example, with reference to the accompanying drawings.

[0014] Fig. 1 is a section through part of a closure such as a door which is to receive a cylinder lock; and

[0015] Fig. 2 is a view similar to that of Fig. 1 showing a device according to the invention in situ in the closure.

[0016] Referring to the drawings, there is shown in Fig. 1 a section through part of a closure such as a door (or window), the inside of which door is indicated at "A". At a position where a cylinder lock is desired to be mounted, a rebate 2 is formed in a part 3 of the door which defines an outer skin or leaf of the door.

[0017] A cylinder lock, not shown, is mountable in the door 1 so that its cylinder projects through an aperture 4 in the part 3 for access from the outside of the door by a key operable in the lock to operate the lock on actuation of the differ pins, as is known in the art. The key is insertable in the direction of arrow 'B', and retractable from the lock cylinder in the opposite direction.

[0018] In order to provide a guard against unauthorised tampering with the lock, there is provided a device 5 which is annular in section and has an outer boundary surface 6 which is tapered. The device 5 is mountable in the aperture so that its surface 6 engages a complementary sloping surface 7 of the aperture 4 so that when in situ the outer boundary surface 6 tapers away from the door 1 as shown. The device 5 has a peripheral flange 8 at the inner, in use, end 9 which is received in the rebate 2 in which it is secured by a case (not shown) of the lock, which is at position X, typically comprising a 16mm lockcase.

[0019] Thus, when the cylinder lock is assembled with the door its cylinder projects into the annular device 5 towards the outside of the door 1, which stands proud of the front (exterior) face 3 of the door 1. However, the projecting external part 6 of the device 5 being tapered away from the door, it is difficult if not impossible for a mole wrench, or snapper, to be engaged with the device 5 to obtain sufficient purchase to wrench or snap the device off the lock, to expose the cylinder of the lock to further attack. The lock is thus protected from damage, and the closure 1 is protected against unauthorised entry.

[0020] A separate device 5 has been referred to and described by reference to the drawings. However, it will be understood that the device 5 may be part of the cylinder of the cylinder lock, by being formed integrally therewith as for example by casting or be being made into a single unit by securing a separate device 5 and lock cylinder by brazing, soldering, adhesive and the like.

[0021] In such a composite, integral or one piece construction described, the device 5 and cylinder lock will be mounted as one piece into the aperture 4. There will again be a flange 8 for mounting in the recess 2, to be held in position by a lock case as before.

[0022] It will also be understood that the invention is equally applicable to a double cylinder lock, i.e. one in which there are two cylinder locks, which face in opposite directions, the cylinders being axially aligned and connected by a connecting piece which is essentially an integral part of the two casings of the two locks. Stated in another way, there is a single casing carrying two spaced apart cylinder locks. In such a double lock arrangement, the locks can be operable respectively from inside and outside a closure to which they are fitted.

[0023] The outer lock has, or is assembled with, a device 5.

[0024] Further, in all embodiments, the devices 5 may be of "key-hole", or oval, configuration in end elevation (direction 'B'), and in all embodiments comprises a cylinder guard of the cylinder lock. The lock may project a little beyond the front face 'F' of the device 5, but not sufficient for it to be grasped by a mole wrench or snapper.

[0025] Further, again, the cylinder lock at the inside part 'A' of the door may have a slot or groove in a part for holding differ pins, the slot or groove being adapted to receive securing means such as a screw mounted in a plate which would be substantially parallel to the flange 8, thereby providing with the flange 8 secure anchoring of the lock in the closure.

Claims

1. A device for obviating damage to a cylinder lock in situ on a closure, comprising an outer boundary surface which in use is tapered away from the closure.

2. A device according to Claim 1, comprising a separate device which is adapted to receive a cylinder of a cylinder lock.

3. A device according to Claim 1, the device comprising part of the cylinder of the lock.

4. A device according to Claim 1, the device and cylinder lock comprising a single integral, unit.

5. A device according to Claim 4, the said unit being formed in one piece as by casting, moulding or machining.

6. A device according to any preceding claim, comprising means by which the device is adapted to be secured in a closure.

7. A device according to Claim 6, the means comprising a flange adapted for securing to a closure.

8. A device according to any preceding claim, the boundary surface having a taper complementary to the taper of an aperture in a closure in which it is mounted.

9. A closure, such as a door or window, in combination with a device according to any preceding claim.

Drawing