GB2231608A

GB2231608A - Security bar assembly

Info

Publication number: GB2231608A
Application number: GB8911474A
Authority: GB
Inventors: Roy Stanley Cosford
Original assignee: INDEPENDENT MOTOR FACTORS Ltd
Current assignee: INDEPENDENT MOTOR FACTORS Ltd
Priority date: 1989-05-18
Filing date: 1989-05-18
Publication date: 1990-11-21
Also published as: GB8911474D0

Abstract

A security bar assembly, for protecting window openings against unauthorised access comprises an outer tube (10) and a rod member (12) of circular cross-section captive within the tube and extending along all or substantially all of the length of the tube (10). The member (12) is freely rotatable relative to the tube portion, for example end portions being carried by bearings (22). Opposite end portions of the tube (10) are preferably secured to mounting means for example a header rail (14) by which the assembly may be attached to wall portions bounding an opening across which the security bars are to extend. If desired, the bearing means (22) may be carried in recesses in the header rail (14) so that the bearing region of the bar assembly is less susceptible to attack. <IMAGE>

Description

SECURITY BAR ASSEMBLY This invention is concerned with security bar assemblies and especially with security bar assemblies intended to be positioned across openings, for example windows, in walls to prevent unauthorised entry or exit.

It is well known to mount solid bars secured to walls around regions to be protected, for example window openings, to prevent unauthorised passage through the openings. The bars are commonly made of solid steel of a suitable thickness and hardness in order to resist cutting through the bars. However, it has been found that, even if the bars are made of extremely hard and expensive forms of steel and are of considerable cross-sectional area, bars may be sawn through with relatively little difficulty using a common hacksaw or the like. Thus, the additional security provided by the use of the known security bars is relatively small even if relatively expensive materials are used.

One of the various objects of the present invention is to provide an improved security bar assembly.

In one aspect the invention may be considered to provide a security bar assembly comprising a tube portion and a member of circular or substantially circular crosssection captive within the tube portion and extending along all, or substantially all, of the length of the tube portion, the member being freely rotatable relative to the tube portion.

There now follows a detailed description to be read with reference to the accompanying drawings of two security bar assemblies embodying the invention. It will be realised that these assemblies have been selected for description to illustrate the invention by way of example.

In the accompanying drawings: Figure 1 is a view, partially in section and with parts broken away, showing a first security bar assembly embodying the invention; Figure 2 is a view, partially in section and with parts broken away showing a second security bar assembly embodying the invention; and Figure 3a and 3b are views with parts broken away showing a modified assembly embodying the invention.

The first security bar embodying the invention, shown in Figure 1, comprises a tube portion provided by a tube 10 and a rod member 12 accommodated within the tube 10 and extending along all or substantially all of the tube 10.

The rod member 12 is of circular or substantially circular cross-section and is captive within the tube 10.

The tube 10 is secured to mounting means, namely a header rail 14 by welds 16.

Bearing means 22 is accommodated within the tube 10 and a portion thereof is secured to the header rail 14 by a weld 20. The rod member 12 is secured to a further portion of the bearing means 22 which is freely rotatable relative to the portion of the bearing means 22 fixed to the header rail 14 by the weld 20 and also relative to the tube 10.

The tube 10 is made of any suitable material for example steel and is preferably relatively rigid and strong militating against bending of the tube 10 in a direction transverse to its lengthwise axis. Preferably the tube 10 is also relatively resistant to cutting by means of a hacksaw or the like, although the primary resistance to attack by means of a hacksaw is afforded by the inner rod member 12. The rod member 12 is made of a strong and hard material, for example a good quality steel material, the rod member 12 may, for example, be made of good quality stainless steel and may if desired be chromeplated; chrome plating gives a hard and slippery surface finish.

Although the rod member 12 shown in the first illustrative security bar assembly is a solid member, if desired the rod member 12 may be itself tubular.

The header rail 14 is also made of strong attackresistant material for example steel and is adapted to be attached to wall portions defining a region to be protected, for example wall portions defining a window opening, across which the tube 10, and rod member 12 within the tube 10 extend. For a larger window opening, a plurality of parallel tubes 10 may be provided and these may be reinforced against bending by one or more reinforcement members extending transversely to the lengthwise axis of the tubes 10 and secured to each of the tubes 10. The header rail 14 is built into the wall portion during construction so that its removal would be difficult.

It will be understood that in the first illustrative bar assembly the rod member 12 is supported at the opposite end to that shown in Figure 1 by a similar bearing means and header rail (not shown), parallel to the header rail 14 to which the opposite end of the tube 10 is likewise secured by welds (not shown). However, if desired, the mounting means for the tube 10 at its opposite ends may be provided by different means, for example individual mounting brackets may be provided at one end of the tube whilst a continuous header rail 14 is provided at the other end of the tube.

The second illustrative security bar assembly shown in Figure 2 is in many respects generally similar to that shown in Figure 1 except as hereinafter described. Like numbers represent like parts. The second illustrative security bar assembly likewise comprises a tube 10 and a rod member 12 captive within the tube 10. The tube 10 is secured to a header rail 14 by welds 16 at one end portion.

However, the second illustrative assembly does not include bearing means but rather a loose bush 24 received within the tube 10 and receiving in a loose fit an end portion of the rod member 12 so that the rod member 12 is freely rotatable relative to the tube 10.

The end of the tube 10 is closed by the header rail and an end portion of the bush 24, so that the rod member 12 is captive.

The various parts of the second illustrative assembly are made of similar material to those corresponding parts of the first illustrative assembly.

The security bars of both of the illustrative assemblies look, externally, very similar to known security bars. However, should an attempt be made to saw through the bars of the illustrative assembly using a hacksaw, whilst this may cut relatively easily through the tube 10, when the blade strikes the inner rod member, the blade tends to slip on the hard material of the rod member 12. Should a slight purchase on the rod member 12 be gained by the hacksaw blade, the rod member 12 merely spins in the bearing means 22 or bush 24. Thus, it is extremely difficult to cut through the inner rod member 12.

The bearing means 22 shown in the first illustrative assembly may comprise ball or roller bearings but this construction would tend to be more expensive than that shown in Figure 2 merely using loose bushings to support the member 12 for free rotation.

In a further embodiment the bearing means 22 or bushes 24 may be omitted entirely, provided that sufficient clearance is left for the rod member to rotate freely.

If desired the bearing means 22 or bushes 24 may be mounted in recesses in the header rails and the end portions of the rod member 12 may be thus supported in the recesses to further reduced susceptibility to attack.

As bending the the tube portions could cause the miner rod members to jam preventing them rotating freely and thus making them more readily cut, the inner rod member may be articulated or made effectively flexible.

For example, by making the rod member up from a plurality of relatively short cylindrical parts 12a with ball bearings 15 interposed between the ends of adjacent short parts 12a providing a moveable buckle, the rod member will move with the tube 10 if this is bent yet will still rotate freely if an attempt is made to cut through using a hacksaw (see Figures 3a and 3b).

The illustrative assemblies are much more resistant to attack by hacksaw blades than previously known security bar assemblies.

Claims

1. A security bar assembly comprising a tube portion and a member of circular or substantially circular crosssection captive within the tube portion and extending along all, or substantially all, of the length of the tube portion, the member being freely rotatable relative to the tube portion.

2. An assembly according to Claim 1 comprising mounting means to which opposite end portions of the tube portion are secured and which are adapted to attach the assembly to wall portions bounding a region across which the tube portion is to extend.

3. An assembly according to Claim 1 wherein the mounting means comprises two spaced mounting members, the end portions of the tube portion being welded to the mounting members.

4. An assembly according to Claim 3 wherein the mounting members are parallel, or substantially parallel bars, the assembly comprising a plurality of parallel or substantially parallel tube portions with a freely rotatable captive member in each tube portion.

5. An assembly according to any one of the preceding claims comprising bushes at opposite end portions of the tube portion, receiving opposite end portions of a captive member for free rotation.

6. An assembly according to any one of Claims 1 to 4 comprising bearing means mounted at opposite end portions of the tube portion adapted to mount a captive member for free rotation in the tube portion.

7. An assembly according to any one of the preceding claims wherein the captive member has a coating of a hard wear-resistant material.

8. An assembly according to any one of Claims 2 to 7 wherein the end portions of the captive member are received in recesses in the mounting means for free rotation.

9. A security bar assembly constructed arranged and adapted to operate substantially as hereinbefore described with reference to the accompanying drawings.