GB2432856A

GB2432856A - Security device

Info

Publication number: GB2432856A
Application number: GB0623789A
Authority: GB
Inventors: Leonard Malcolm Pendlebury
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-11-30
Filing date: 2006-11-29
Publication date: 2007-06-06
Also published as: GB0524336D0; GB0623789D0; WO2007063287A1

Abstract

The invention relates to a security device in the form of an elongate element and comprises a plurality of blocks 14a-c of friction material mounted inside an elongate hollow element 12, such as a box section steel housing, in a parallel array. Spring means 16 located between the blocks hold them in compression. Such elements 12 may be mounted to or built into the walls of security enclosures, buildings or safes to deter thieves from cutting through the elements 12 with cutting or grinding equipment. If a thieve cuts into any one of the blocks of friction material 14, the equipment will cease to operate due to the compressive force under which the blocks are held. The blocks 14a-c are arranged with associated spring means 16a-c in parallel rows with the respective blocks and springs of each row offset, so that the springs 16a-c of any one row overlap the location of the friction material blocks 14a-c of the adjacent row. Wherever a cutting tool penetrates it will always encounter a friction block, even in cases when it first encounters a spring. The blocks 14a-c may be enveloped in non-friction material 18 to ensure that parallel blocks can slide relative to each other.

Description

P1121736B1 1 2432856

SECURITY DEVICE

This invention concerns a security device in the form of an elongate element.

Thieves are increasingly sophisticated and are often equipped with cutting or gnnding apparatus in order to gain entry to security cabinets in which valuables may be stored or to break open security doors to premises or parts of premises. Sometimes, even the fabric of a building, such as a warehouse constructed of prefabricated panelling, may be attacked with cutting or grinding machines for purposes of robbery.

An object of the invention is to provide some means to prevent or severely inhibit the possibility of unauthorised access to an enclosure or area by use of cutting or grinding equipment.

Prior patent specifications CH6771 28, DE3533554 and ES2I 84542 each disclose a security device comprising a body of friction material mounted under pressure of spring means inside a hollow element. In the case of DE3533554, a plurality of alternate friction material bodies and springs are arranged in a line.

The present invention aims to provide a more effective device than these.

Thus, a security device in accordance with the present invention is characterised in that the plural bodies of friction material are arranged inside the hollow element such that a first body extends substantially parallel to a second body, in that separate spring means are associated with each of the first and second bodies to hold them under respective spring bias in parallel disposition, and in that the positions of the respective bodies and spring means are offset from each other such that the spring means providing bias to the first body is positioned to overlap and lie adjacent to a region of the second body, while the spring means providing bias to the second body is positioned to overlap and lie adjacent to a region of the first body.

In preferred practical embodiments of the invention a plurality of first bodies of friction material are arranged in alignment with first spring means there between and a plurality of second bodies of friction material are arranged in alignment with second spring means there between, said first bodies and first spring means extending substantially parallel to said second bodies and second spring means.

P112173G81 The hollow element suitably comprises a length of box section steel, or else a steel tube.

However, the element could also be formed of any other suitable tough metal or other material. The friction material is suitably any type of material conventionally used to produce brake blocks, brake pads and brake linings. The spring means may comprise any type of spring means, such as one of more helical springs, leaf springs, torsion springs, gas springs, or even suitable blocks of resilient material, which can be held under compression for lengthy periods without losing their expansion properties.

The device of the invention is suitably in the form of a bar which can be mounted onto the interior surface of a security housing, or security door, or wall to a premises etc. If a would-be thief attempts to cut through the device with any currently known cutting or grinding equipment, and cuts into the friction material, the said equipment will cease to operate effectively and will be immobilised. It will be jammed owing to the pressure under which the friction material is held within the hollow outer casing of the device. The activities of the perpetrator will, accordingly, be curtailed and the equipment will be retained and no longer available for use.

The staggered arrangement of the parallel friction bodies and their associated springs in the present invention ensures that there is no gap along the length thereof where a cutting tool might penetrate the device only at a position where a spring means is located, and thereby be able to cut right through to the other side. In the event that a spring is first encountered by a cutting tool, the tool will soon after reach a friction body extending parallel thereto and at that point its progress will be stopped.

In a further advantageous development of the present invention, at least some of the bodies of friction material are enclosed within an envelope of non-friction material. This ensures adequate ability of the parallel friction bodies to slide relative to each other in order to trap any cutting tool which penetrates the outer element in which the friction bodies are housed.

In practical embodiments each body of friction material may suitably be wrapped in a sheet of flexible plastics material or placed inside a bag of flexible plastics material.

However, there are other possibilities for providing the said envelope of non-friction material. For example, each body of friction material may have a surface layer, such as a surface coating, of non-friction material. Alternatively, each body of friction material may be individually packed into a rigid or semi-rigid hollow casing of plastics material, P112173081 prior to arrangement within the outer element. Yet another possibility is that the friction bodies are not individually enveloped in non-friction material, but aligned first bodies and first spring means are enclosed within a common envelope of non-friction material, and aligned second bodies and second spring means are, optionally, also enclosed within a respective common envelope of non-friction material. Such envelopes may be wrappings or bags of flexible plastics material, or casings of rigid or semi-rigid material.

The invention will be described further, by way of example, with reference to the accompanying drawing, in which: Figure 1 is a perspective view of an embodiment of a device in accordance with the invention, with internal detail shown schematically in broken outline; and Figure 2 is a perspective view of an individual friction block from the embodiment shown infigurel.

As shown, a preferred practical embodiment lOaf the device of the invention comprises a steel box section housing 12 of elongate form inside which there are a plurality of blocks 14 of friction material, as used for making brake blocks, and a plurality of heavy duty helical springs 16. The box section housing 12 is of rectangular cross-section.

Typically, it may be approximately 20 mm x 60 mm and from 0.5 to I m in length. The individual blocks of friction material may then be approximately 20mm x 20mm in cross section. Of course these dimensions are only by way of example.

The blocks 14 and the springs 16 are packed into the hollow casing 12 in an arrangement of three substantially parallel rows, in which the respective blocks and springs are designated by the suffixes a, b, c. Thus, in the top row, two blocks 14a (first blocks) of friction material extend in alignment, that is to say coaxially, and are separated by a first spring 16a. In the middle row, two blocks 14b (second blocks) of friction material extend in alignment, but substantially parallel with the first blocks 14a, and are separated by a second spring 16b. In the bottom row, two blocks 14c (third blocks) of friction material also extend in alignment, but substantially parallel with the second blocks 14b, and are separated by a third spring 16c. Each of the springs 16a, b, c are held under compression and exert spring pressure on the friction blocks with which they are in line. This may be accomplished by use of a hydraulic ram to compress the contents of the housing 12 towards a closed end (not shown) of the housing before the P1 12173601 remaining open end 13 of the housing is closed off. In this respect, the ends of the housing 12 may be closed off by respective end caps, or by a series of discrete end stops 15, as shown in figure 1, or by any other suitable means, such as transverse bolts.

The respective ends may be closed off in different manner to each other.

As shown, an important feature is that the friction blocks 14a, b, c, and the springs 16a, b, c in the respective rows are staggered relative to each other so that the springs 16 in each row do not coincide in their position along the housing 12. Instead, each spring 16 is overlapped by, that is to say it lies adjacent and side-by-side with a region of a respective friction block 14 in the other two rows.

This arrangement ensures that the device is highly effective in blocking operation of a cutting machine irrespective of the position at which the cutting machine initially penetrates. If the cutting machine penetrates the device at a location where a friction block 14 is extending, it will be immobilised immediately by the force of the spring pressure exerted on that block, If the cutting machine penetrates in the region of a spring 16, the immediate blocking of same is likely to be less effective, but the machine will soon encounter the overlapping friction block of the adjacent row and be effectively immobilised by same. Accordingly, with this side-by-side, staggered arrangement where the extent of each spring 16 is fully overlapped by the extent of a friction block 14 in the adjacent substantially parallel row, there is no position along the length of the device where it can be less effective.

Each of the friction blocks 14 is wrapped in non-friction material, for example a flexible polythene sheet 18, as shown in figure 2. This ensures that the respective blocks 14a, b, c in the parallel rows are able to slide sufficiently relative to blocks in adjacent rows in order to effectively immobilise any cutting tool in the manner described. Without such a non-friction layer between the friction blocks in adjacent rows there is a risk that they may inhibit movement of each other. The wrapping of the friction blocks also facilitates initial assembly of the blocks 14 into the box section housing 12.

The device 10 can be mounted, for example, inside a security cabinet, adjacent the interior surface of the cabinet, or onto a wall by means of double-sided adhesive tape, shown schematically at 19 in figure 1.

P112173GB1 Even use of a torch style cutting machine which acts by burning through sheet material will be blocked as the type of friction matenal used for the blocks inside devices of the invention is not itself flammable or meltable by this type of cutter.

The foregoing embodiment is only illustrative and many variations are possible in other embodiments of the invention. Several possibilities for enveloping the friction blocks in a non-friction layer have been mentioned prior to the description of the illustrated embodiment. Other details may also vary. For example, the hollow element housing the blocks and springs may be in the form of a cylindrical tube and the blocks themselves may be of cylindrical form. The springs may be compound leaf springs instead of helical springs, or any other type as previously mentioned. The number of parallel rows of blocks and springs, and the number in each row may vary from the illustrated embodiment. The device may be mounted for use in any suitable manner, or by any suitable means or even built in to the cladding of a building structure.

Claims

P112173G81

CLAIMS

1. A security device comprising a plurality of bodies of friction material mounted under pressure of spring means inside an elongate hollow element, characterised in that the bodies are arranged inside the hollow element such that a first body extends substantially parallel to a second body, in that separate spring means are associated with each of the first and second bodies to hold them under respective spring bias in their parallel disposition, and in that the positions of the respective bodies and spring means are offset from each other such that the spnng means providing bias to the first body is positioned to overlap and lie adjacent to a region of the second body, while the spring means providing bias to the second body is positioned to overlap and lie adjacent to a region of the first body.

2. A device according to claim I comprising a plurality of first bodies of friction material arranged in alignment with first spring means there between and a plurality of second bodies of friction material arranged in alignment with second spring means there between, said first bodies and first spring means extending substantially parallel to said second bodies and second spring means.

3. A device according to claim 1 or 2 wherein each body of friction material is enclosed within a respective envelope of non- friction material.

4. A device according to claim 3 wherein each body of friction material is wrapped in a sheet of flexible plastics material.

5. A device according to claim 3 wherein each body of friction material has a surface layer of non-friction material.

6. A device according to claim 2 wherein aligned first bodies and first spring means are enclosed within an envelope of non-friction matenal.

7. A device according to claim 6 wherein aligned second bodies and second spring means are also enclosed within a respective envelope of non-friction material.

8. A device according to any preceding claim wherein the hollow element is in the form of a box section steel housing.

P112173G81 9. A device according to any preceding claim wherein each body of friction material is in the form of a block of brake pad material.

10. A security device substantially as hereinbefore described with reference to and as illustrated by figure 1 of the accompanying drawing.