GB2237434A - Intruder alarm external sounder housing - Google Patents

Abstract

A housing comprising of a backplate 9 that incorporates a means of attaching a module containing the sounder(s) and associated electronics, the means being lugs 10 and a threaded hankbrush 11. A cover 1 that is secured at the top of the housing by the integral return lip 14, and is secured to the bottom of the backplate by two high security bolts 7, these bolts being screwed through the lid into the fixings in the backplate 12. The cover has two recesses 2 to accommodate the heads of the high security bolts 7 so that they are not exposed to the threat of attack. Behind the front louvres 3 on the inside of the cover there is a unique reverse louvre baffle 5. This is a physical barrier against the injection of cavity filling foam. The shape of the cover is a truncated pyramid with the sides inclined by 15 DEG so that the housing is not vulnerable to lasso attacks. <IMAGE>

Description

INTRUDER ALARM EXTERNAL SOUNDER HOUSING The invention relates to an external housing for intruder alarm sounders The external sounder housing is the only indication to the public and the criminal fraternity alike that a property is protected by an effective alaml system. The external sounder housing performs the function of a visible deterrent and audible warning. It is one of the main means by which someone not involved in the industry can gauge the quality and standing of an alarm company and it's installations.

Intruder alarm external sounder housings can be seen almost everywhere. The) come in a wide range of shapes and sizes, and are made in a variety of materials, such as polycarbonate, plastic and metal.

Every external sounder housing has one shortcoming or another, examples of these might be the shape that is inviting to an intruder to lasso it to gain access to it, or even to pull it off the stricture it is attached to. Another shortcoming could be the vents or louvres that let the sound out. They could, in fact, invite the penetration of objects to interfere with the internal workings of the sounder. Also, the vents are an open door for the injection of cavity filling foam vThich, when it comes into contact with air, expands and then sets very rapidly.The injection of foani into the sounder housing nvill seriously damage the internal working of the sounder to the point where they might be completely muffled or not function at all.

Housings made of plastic, polycarbonate or moulded PVC are increasingly coming tinder attack due to there comparative softness and vulnerability to heat (blow torches, etc), and shalt knives.

Another area for consideration is the fixing of the housing lid to the baekplate or box. Thins is of extreme importance - for instance if ordinary slotted screws are used then tamEzexitlg becomes easy, or if the fixings are protruding from the lid then they become vulnerable to being sax n off with a backsaw or even chiselled off with a hammer and cold chisel.

The reason for this invention is to design an external sounder housing that incorporates a number of features to deter any tampering such as lasso and foam attacks, unauthorised access into the housing and leverage from the structure to which it is attached, resulting in the sounder being silenced by an intruder.

According to the present invention there is provided an external sounder housing comprising of a 2mm zintec steel backplate (A) that is rawlbolted and screwed to masonry. The cover (B) is manufactured from 1.2mm galvanised zintec steel, incorporating eight louvres for maximum sound output and a unique reverse louvre on the inside for physical protection against the injection of foam. The corners of the cover are seam welded for improved strength and the sides are inclined by 150 to be less vulnerable to lasso attempts. The cover is galvanised prior to a powder coat finish offering maximum durability.

The housing cover is attached to the backplate by hooking the return lip of the cover over the top of the backplate, then pull the cover down whilst closing the cover bottom against the bottom of the backplate, whereupon the two high security fixings are secured until their heads are in the recesses provided and the fixings are tightened to the required torque.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings, on which: Figure 1/11 shows a front view of the housing cover.

Figure 2/11 shows a side elevation of the housing cover viewed from the right.

Figure 3/11 shows a top view of the housing cover viewed from above.

Figure 4/11 shows a side elevation of the housing cover viewed from the left.

Figure 5/11 shows a view of the inside of the cover from behind.

Figure 6/11 shows a view of the cross section through the housing cover.

Figure 7/11 shows a front view of the backplate.

Figure 8/11 shows a view of the backplate from the right hand side.

Figure 9/11 shows views of the cover fixing bolts.

Figure 10/11 shows views of the fixing bolt plastic washer.

Figure 11/11 shows a view of the "lid to backplatel' fixing method.

FIGURES 1. Front view.

2. Side elevation viewed from right hand side.

3. Top view.

4. Side elevation viewed from left hand side.

5. View of inside of cover from behind.

6. Cross section of cover.

7. Front view of backplate.

8. Side view of backplate from right hand side.

9. Views of cover fixing bolts.

10. View of cover fixing bolt plastic washer.

11. View of lid to backplate fixing via bolt and washer.

Referring to the drawings 1111 to 11/11, the external sounder housing comprises of a 2mm zintec steel backplate 9. The backplate incorporates two lugs 10 and a threaded hankbush 11 for the attachment of a sounder module. The backplate also has two threaded hankbushes 12 for the securing of the lid fixing bolts 7. The holes in the backplate 13 are for fixing the backplate to the structure of the building.

The cover of truncated pyramid design 1, the sides of which are inclined 4 by 150 to deter lassoing. It incorporates eight louvres 3 for maximum sound output, and a unique reverse louvre 5 that chokes cavity filling type foam and stops it getting into the sounder module if it is injected into the sounder housing via the front louvres 3.

The cover incorporates recessed high security fixings, the function of the recess 2 being to deter chiselling off or hacksawing off of the heads of the cover fixing bolts to remove the cover and gain access to the sounder module The cover fixings themselves 7 are of PIN hexagon design for maximum security against tampering. The cover fixings have a plastic top hat type washer 8 to insulate the screw from the lid.

The top of the cover 1 is secured to the backplate by hooking the lip of the cover 14 over the top of the backplate.

Claims (5)

1. An external intruder alarm sounder housing comprising of a backplate and a cover. The cover incorporates eight louvres for maximum sound output and a unique reverse louvre.

The shape of the cover is a truncated pyramid with the sides inclined at 150. The cover fixing locations are recessed so that the heads of the cover fixing bolts are not exposed

2. An external intruder alarm sounder housing as stated in Claim 1 wherein the backplate is so designed that the cover can be secured to it by hooking on the top of the cover over the backplate, then the bottom of the cover is then closed down to the bottom of the backplate.

3. An external intruder alarm sounder housing as stated in Claim 1 and in Claim 2 where the cover fixing bolts are of a pattern that is of high security PIN hexagon type.

4. An external intruder alarm sounder housing as stated in Claim 1 where the reverse louvre is so arranged in design and location as to let the maximum sound out, but no let cavity type filling foam in.

5. An external intruder alarm sounder housing as described herein with references to the accompanying drawings 1/11 to 11/11.