GB2356491A

GB2356491A - Improved fittings

Info

Publication number: GB2356491A
Application number: GB9926508A
Authority: GB
Inventors: Paul Michael Boggia
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-11-10
Filing date: 1999-11-10
Publication date: 2001-05-23
Also published as: GB9926508D0

Abstract

When fixing an electrical fitting to a surface it is normal to firstly fit a mounting-box to the surface and subsequently, once wiring is completed, secure the front cover to the mounting-box. The fitting 10 comprises one or more elongate fixing means 11A,B securable at a first end to the mounting-box 12 , and having a second end passable through the front cover 15 in one direction only, and which once passed through secures the front cover 15 to the mounting-box 12. The or each end of the fixing means 11A,B can have a number of retaining means 22 integrally formed therewith and which to be in the form of a linear series of frustums of cones arranged end to base. The retaining means 22 may be formed from a resilient material.

Description

2356491 IMPROVED FITTINGS Field of the Invention The present invention

relates to fittings and particularly to electrical fittings such as light switches, sockets and the like. Background to the Invention When fixing an electrical fitting to a surface such as a wall it is usual to first fix a 10 mounting-box to the surface. The front cover, once the wiring is in place is then secured to the mounting-box. This is normally accomplished by means of screws, the shanks of which pass through the front cover to engage correspondingly threaded lugs present in the mounting-box. Even when this procedure passes without problem, it can be time consuming. 15 Moreover, the length of the fixing screw is such that a significant proportion of it is effectively not used, passing beyond the lug. This is not only a waste of materials but also a waste of the installer's time in fixing the screws into position. There are also additional problems using the above described system. Firstly, once one screw has been located and at least partially screwed into position, the second 20 one is then effectively being screwed "blind" into its current location. This brings the potential problems of locating the second screw into its lug. Moreover, a small inaccuracy can lead to cross-threading the screw, and damage to the lug itself A further problem arises due to the way work is normally organised, particularly in new building installations. Quite often the mounting-box is fitted to a wall as 25 part of the wiring installation. Plastering then takes place which can result in plaster accumulating in the threads of the lugs and the mounting-box. The thread must then be cleared prior to fixing the front cover.

Furthermore, the appropriately sized and shaped screwdriver needs to be to hand, which is quite often not the case when moving from location to location within a building or building site. Although each of the problems individually does not necessarily require a great deal of time to overcome, when a large number of fittings are being installed, the time loss can be significant.

1.

Difficulties can arise with conventional fittings, in that should the screws become lost or damaged, then new screws of the appropriate size and having the appropriate thread need to obtained.

Also, the positioning of the holes for screws in a replacement front cover may be such that the screws are not aligned with the lugs in the old mounting box which would then require a new mounting box to be installed.

Finally, a safety aspect arises with conventional fittings in that they are easily opened with a screwdriver which can be a particular danger to young children.

It is an object of the present invention to seek to alleviate the above disadvantages and to provide fittings which are safer and can be more conveniently installed In this application the term "mounting box" should be taken to include pattresses, joint boxes, back-boxes and the like.

Summary of the Invention

According to the present invention there is provided a fitting such as for an electric light switch, the fitting including a front cover or plate and a mountingbox or back-plate, adapted to receive and/or retain the front cover, the fitting further including one or more fixing means, comprising one or more elongate members, each having a first end securable to the mounting box and a second end 25 which in use is passed through an aperture in the front cover in one direction only, towards the in-use outer surface of the fitting, such that having passed through the front cover it acts to secure the front cover to the mounting-box.

The or each end of the first and second ends of the fixing means preferably has a number of retaining elements integrally formed therewith.

The retaining elements are preferably in the form of a linear series of frustums of cones arranged apex to base.

The retaining elements are preferably formed from a material which by virtue of is shape resiliently deforms in one direction but accumulates in compression when a force is applied in the opposition direction.

Alternatively, the retaining elements comprise a series of projections such as raised bands to allow the free ends to pass in one direction only through the front cover. The fixing means may be permanently attached to the mounting-box.

Preferably, the mounting-box comprises means to engage one or more retaining members of the fixing means.

The fixing means is preferably inelastic along at least part of its length.

Alternatively, the fixing means can be slightly extensible along any part of its length between the retaining members.

The front cover preferably comprises one or more apertures to allow passage of the fixing means.

The mounting-box and/or front cover advantageously comprises one or more guide lugs which engage corresponding recesses to assist in achieving the correct orientation of the mounting-box and front cover.

According to the invention there is also provided a method of securing a front cover or plate to a mounting-box or plate of a fitting, the method including:

passing fixing means, secured to the mounting-box, through an aperture in the fixing means the front cover, being of a composition and shape such that the fixing means can be passed through in one direction only, positioning the front cover in the required position in relation to the mounting box-, tensioning the fixing means by a force applied by hand or with a hand tool such as pliers, so that the fixing means act to hold the front cover in the required position.

According to a further aspect of the invention there is provided fixing means, for use in securing the mounting box of an electric fitting to the front cover or plate, the fixing means comprising one or more elongate members the elongate members being provided with retaining members at each of their ends.

Brief Description of the Drawing

The present invention will now be described more particularly with reference to the accompanying drawings which show, by way of example only, two embodiments of electrical fittings according to the invention. In the drawings:

Figure I is a cross-sectional plan view taken through a first embodiment of fitting- Figure 2 is an enlarged sectional detail of the fitting shown in Figure I Figures 3a and 3b are a perspective and a sectional plan view of the first embodiment of fittings showing a mounting-box together with a fixing strap before and after insertion in a fixing lug respectively-, Figure 4 is a perspective view of a mounting box of the second embodiment of 20 fitting-, Figure 5 is a perspective view of a front cover for use with either embodiment of fitting, for use as a mains or light switch-, Figure 6 is a perspective view of a modification for aligning a mountingbox with the front plate or cover of a fitting; and Figure 7 illustrates how a fixing strap is trimmed after the fitting Is secured.

Figure 8 is a side view of further example of a fixing strap.

Detailed Description of the Preferred Embodiments

Figure I shows a section through a fitting generally referenced 10. The fitting comprises straps I IA, B (here illustrated diagrammatically) which as shown here have not yet been trimmed to their required size. The fitting comprises a mounting-box 12. In use the mounting-box 12, is fixed by means of screws (not illustrated) to the wall 13. The mounting-box 12 has two lugs 16A, B each having a hole when fixing the front plate 15 to the mounting-box 12 the straps I I A, B pass through the holes in the lugs 16A, B. Each of the straps I I A, B then passes through a side wall 14A, B of front plate 15.

In Figure 2, the strap 21 has at one of its ends a series of retainers 22, each in the form of A frustum of a cone, the end retainer 23 having a rounded end. The retainers 22 and 23 are formed from resilient material which allows them to be pushed through the hole 24 in the lug 25. The diameter of the base of the cone in the retainers 22, 23, is greater than that of the hole 24 in the lug 25. This together with the shape of the retainers 22 and 23 is however such that once they have been pushed through the hole 24, they cannot be removed without breaking. Section 26 of the strap 21 is made of inelastic material. At the other end of the strap 21 is a further series of retainers 27. The individual members of the series are formed from resilient material and have the shape of a frustum of a cone. The retainers 27 are pushed through the hole 28 of the inside wall 29 of the front plate 30. As with the retainers 22, the retainers 27 are prevented from going back through the hole 28 due to their shape. Once the retainers are in place therefore, the front plate 30 is held in position against mounting-box 12.

The process of positioning the retainers 22 in the lug 25 of the mountingbox 12 is again illustrated in Figures 3a and 3b.

Figure 4 shows a further example of a mounting-box 12, in which retainers are passed through a hole 41 into an enclosed space within the mountingbox 12. The retainers are thus prevented from interfering with, or from being contaminated with material from inside the mounting-box 12.

Figure 5 shows an embodiment of a front cover 51 for use in, for example, a light switch. In use, the strap is pulled through the hole 52, and the section retained after cutting, which protruded from the hole 52, sits in the rebate 53 formed in the front cover 5 1.

Figure 6 illustrates guide members 61A, B added to the surface 62 of the mounting-box 63. In use, the surface 62 is placed in contact with a front cover (not illustrated in Figure 6). The front cover comprises complementary recesses into which the guide members 61 A, B sit. These therefore facilitate positioning of the front cover and the mounting-box 63 to their correct relative orientation.

Figure 7 illustrates the method by which the strap is attached. In this illustration the strap 71 is permanently fixed to the lug 72 of the mounting-box 63. The front piece 74 is then positioned against the surface 75 and the strap 71 then pulled through the hole 76 in the front piece 74. Tension is then applied either by hand or with the aid of a tool such as pliers to the strap 71 along its length, and the retainers cut along line 77. When this tension is released, the resilience of the retainers 78 ensures that they then pull in a direction back towards the mounting box 63, thus holding the mounting-box 63 and the front piece 74 together.

The invention as described above, therefore means that fittings such as socket boxes or light switches can be quickly assembled without the need for using screw fittings.

The fittings according to the present invention provide an improvement aesthetically, as there are no screws visible, but more importantly they provide improvements from a safety perspective should the inside of the assembled fitting became live, then there are no metal parts, such as screws, to conduct the electricity to the outside.

The fitting can be quickly disassembled in the event of repairs or simply to change the front cover for a different design. This can be achieved by simply cutting off the resilient means from the outside. Once any work has been done then the front cover can be fixed in position again by using a new strap.

In addition to the configuration of the retainers shown in Figure 2, usually known as a "fir tree" a number of other modifications can be made without departing from the scope of the invention.

Firstly as illustrated in Figure 8, the ends can be in the form of a flat strip 81, having ridges 82 transverse to its longitudinal length. The strip is then passed through a suitably sized and proportioned hole in the mounting-box or front cover, and as with the "fir tree" of Figure 2, the shape and material of construction would prevent the end piece from being pulled back through the hole, once it is in.

Alternatively the retainers could be in the form of barbs or spines, which allow passage of the retainer in one direction through a hole, but which are forced apart from each other should an attempt be made to pull them back through the hole.

The barbs or spines are so designed to resist being forced apart, and therefore motion in the reverse direction is opposed.

The guides shown in Figure 6, can also be made such that they form a pushfit connection with the section of the fitting to which they are to be joined. In this manner the parts of the fitting are further stabilised against relative motion.

The front cover as illustrated could also comprise a cover for the rebate. This not only improves the appearance of the fitting, but also improves the safety by reducing access of for example small children, to the fitting.

The straps and fixing means used will usually be of limited elasticity along the connection between any retainers or point where the strap is attached to the mounting-box. Any elasticity will be sufficient to allow the retainers to be pulled out, cut and then be pulled back by tension in the rest of the strap, the tension being sufficient to hold the front cover and the mounting-box together.

The above described straps are such that they can be used within existing back boxes as well as those designed particularly to receive the retaining means of the straps. With existing mounting-boxes the retaining means could be passed through the threaded holes which would normally engage the threaded portion of a screw.

It will of course be understood that the invention is not limited to the specific details described herein, which are given by way of example only, and that various modifications and alterations are possible within the scope of the invention.

Claims

Claims

A fitting of the type used, for example with an electric light switch, the fitting comprising:

a front cover or plate-, a mounting box or back plate, adapted to receive and/or retain the front cover; and at least one elongate fixing member having a first end suitable for anchoring either to the mounting box or front cover and a second end which in use is passed through a retaining aperture in, respectively, the front cover or mounting box the second end comprising retaining elements to secure the front cover or plate to the mounting box or back plate.
2. A fitting according to Claim 1, wherein the first end of the fixing member has a number of retaining elements integrally formed therewith.
3. A fitting according to either Claim I or Claim 2, wherein the or each retaining element is in the form of a linear series of fi-ustums of cones arranged apex to base.
4. A fitting according to any preceding claim, wherein the or each retaining element is formed from a material which by virtue of its shape resiliently deforms in one direction but accumulates in compression when a force is applied in the opposite direction.
5. A fitting according to either Claim I or Claim 2, wherein the or each retaining element comprises a series of projections such as raised bands to allow the free ends to pass in one direction only through the retaining aperture in the front cover or mounting box.
6. A fitting according to any preceding claim, wherein the first end of the fixing member is bifurcated.
7. A fitting according to any preceding claim, wherein the second end of the fixing member is bifurcated.
8. A fitting according to any preceding claim, wherein the mounting box comprises means to engage one or more retaining elements of the fixing member.
9. A fitting according to any preceding claim, wherein the fixing member is inelastic along at least part of its length.
10. A fitting according to any of Claims I to 8, wherein the fixing member is slightly extensible along any part of its length between the retaining elements.
11. A fitting according to any preceding claim, wherein the front cover comprises one or more apertures to allow passage of the fixing member.
12. A fitting according to any preceding claim, wherein the mounting box and/or front cover comprises one or more guide lugs which engage corresponding recesses to assist in achieving the correct orientation of the mounting-box and front cover.
13. A method of securing a front cover or plate to a mounting box or plate of a fitting, the method including:

passing fixing member, secured to the mounting-box or the front cover, through an aperture in, respectively, the front cover or mounting box, the fixing member being of a composition and shape such that the fixing means can be passed through in one direction only, positioning the front cover in the required position in relation to the mounting box; tensioning the fixing member by a force applied by hand or with a hand tool such as pliers, so that the fixing member act to hold the front cover in the required position.
14. A fitting substantially as herein described with reference to and as illustrated in the accompanying drawings.
15. A fixing means, for use in securing the mounting box of an electric fitting to the front cover or plate, the fixing means comprising one or more elongate members the or each elongate member being provided with I retaining elements at each of their ends.
16. A method of securing a front cover to a mounting plate of a fitting substantially as herein described with reference to the accompanying drawings.