GB2597516A

GB2597516A - Pattress box

Info

Publication number: GB2597516A
Application number: GB2011540.8A
Authority: GB
Inventors: Longfellow Richard; Westcarr Ashley
Original assignee: Trade Secrets International Ltd
Current assignee: Trade Secrets International Ltd
Priority date: 2020-07-24
Filing date: 2020-07-24
Publication date: 2022-02-02
Anticipated expiration: 2040-07-24
Also published as: GB202011540D0; GB2597516B

Abstract

A pattress box comprises a base 1, an open face 6 surrounded by an outwardly directed flange 5 extending in a plane parallel to the plane of the base 1, and an opposed pair of side walls 2. Each side wall has an aperture 7 opening through the base 5 for receiving a respective slider 30. Each slider 30 has a main portion 31 for sliding engagement with the aperture 7, a tab 34 projecting from a first face of the main portion 31 through said aperture 7 to extend parallel to the flange 5 in use, and a projection 35 from the opposite face of the main portion 31 providing a screw threaded socket engageable by a screw which in turn bears on the base 1 of the box, whereby rotation of the screw causes movement of the tab 34 towards or away from the flange 5.

Description

PATTRESS BOX

Field of the Invention

This invention relates to a pattress box for use in mounting an electrical device such as a socket or switch in a plasterboard wall.

Background to the Invention

The internal walls of buildings are typically constructed by creating a timber framework and then attaching plasterboard to the external faces of the wall. The plasterboard walls are then usually finished with a skim of plaster. Any electrical wiring is conveniently installed before the plasterboarding is attached and apertures are created corresponding to the locations where electrical de- vices such as switches and power sockets are to be installed at a later stage. For convenience in the later installation stage, a pattress box is inserted in the aperture in the plasterboard and the cable ends located in the box temporarily until the plaster skim has been completed and the electrical devices are in-stalled.

A known type of pattress box which has found widespread use is in the form of a moulded plastic box having a flange around which sits against the plasterboard external surface with the remainder of the box pushed into the aperture cut in the plasterboard. Snap-in sliders are provided in apertures in op-posed sides of the box, the sliders having threaded sockets engageable by the fixing screws used to attach the electrical device so that, as the screws are tightened, the sliders engage the rear face of the plasterboard (i.e. internal to the timber framework), thereby locking the pattress box in place.

A problem with this arrangement is that the pattress box is not fixed in position until the electrical device is screwed in place, and so there is a risk that the finished plaster (and any paint layer thereon) can be damaged around the pattress box during the final electrical fix, which involves drawing the electrical cables out of the box, trimming them and attaching them to the electrical device. This often requires calling the plasterer and painter back for remedial work around the switches and sockets and the like after the electricians have finished -2 -their work. This adds to the cost and may delay completion of the construction project.

Summary of the Invention

According to the invention, a pattress box comprises a base, an open face surrounded by an outwardly-directed flange extending in a plane parallel to the plane of the base, an opposed pair of side walls extending between the base and the flange, each side wall having an aperture therein for receiving a respective slider, said aperture opening through the base, each slider having a main portion for sliding engagement with the aperture, a tab projecting from a first face of the main portion through said aperture to extend parallel to the flange, in use, and a projection from the opposite face of the main portion providing a screw threaded socket engageable by a screw which in turn bears on the base of the box, whereby rotation of the screw causes movement of the tab towards or away from the flange.

Preferably, a further projection from the opposite face provides a second screw-threaded socket engageable by a fixing screw of an electrical device. The further projection is preferably in the form of a tube engageable with a cut-out in the base opening from said aperture, engagement of the tube with the cut-out serving to guide and locate the slider in the aperture.

The box may comprise a further spaced pair of walls extend from the base to the flange at right-angles to and connecting the side walls. Each of said further walls preferably mounts a screw-threaded socket engageable by a fixing screw of an electrical device.

Each slider is preferably formed as an integral plastic moulding and the 25 or each threaded socket may be formed from a hexagonal threaded nut secured in said moulding.

The main portion of each slider may be provided with a pair of offset larger sections for engagement with inner surfaces of the side walls whereby the main portion slides in the plane of the side wall or parallel thereto.

The pattress box of the present invention is simple to install and reduces the need for remedial work to the plastering and painting after the final electrical installation. -3 -

Brief Description of the Drawings

In the drawings, which illustrate an exemplary embodiment of the inven-tion: Figure 1 is a perspective view of the pattress box from the front; Figure 2 is a perspective view of the pattress box from the rear; Figure 3 is a front elevation of one of the sliders engageable with the pat-tress box, in use; Figure 4 is a rear elevation of the slider of Figure 3; and Figure 5 is a side elevation of the slider.

Detailed Description of the Illustrated Embodiment

Referring to Figures 1 and 2, the pattress box illustrated is for a typical single-gang electrical socket or switch and is thus square in plan, but it will be appreciated that rectangular boxes may be provided for double-or multiple-gang sockets or the like. The box is formed as a plastics injection moulding with a base 1, two opposed side walls 2 upstanding from the base, two opposed end walls 3 upstanding from the base and extending between the side walls 2, and a flange 5 extending around the open face 6 of the box outwardly of the walls 2 and 3. In use, the box is inserted into an opening cut into a plasterboard sheet in a wall so that the flange rests against the plasterboard around the opening.

The side walls 2 each contain an essentially rectangular aperture 7 which extends through to the base to form a rectangular slot 8, which in turn opens into a part-circular cut-out 9. The box is provided with conventional punch-out cable inlets 11.

The apertures 7 each receive a slider 30, as may be seen from Figures 3, 4 and 5. The sliders are of generally conventional form, having a main, es-sentially planar, portion 31 which is dimensioned to fit within the aperture 7 and pass through the slot 8. The main portion 31 has a larger section 32 at one end which serves to hold the slider within the box, preventing it from sliding out and being lost.

A central tubular projection 33 extends along the internal face of the main portion 31 and has a hexagonal formation within it at on end in which is retained a hexagonal threaded nut (not shown). This may be secured by means of adhe- -4 -sive or may be moulded in position. The central tubular projection 33 passes through the part-circular cut-out 9, in use, helping to guide and locate the slider. Because the larger section 32 is offset slightly from the plane of the main portion 31, the main portion 31 can move in or parallel to the plane of the side wall 2, ensuring that the thread in the projection 33 remains correctly aligned for subsequent insertion of the fixing screw for the socket or switch at the final electrical installation stage, regardless of the thickness of the plasterboard. This is especially important where a double thickness of the plasterboard is used; with some conventional pattress boxes, the slider becomes deflected away from the side of the box when it moves further away from the flange 5, preventing inser-tion of the fixing screw. It is therefore necessary for the person installing that type of conventional box to cut away a portion of the internal layer of the plasterboard to permit correct operation of the slider. This is difficult to achieve through the limited opening provided for the box in the plasterboard.

The opposite face of the main portion 31 is provided with a projecting tab 34 which is of a width such that it just passes through the aperture 7 when the slider is inserted into the box after the box has been positioned in the opening in the plasterboard. The tab is configured to engage the reverse side of the plasterboard to that engaged by the flange 5.

The internal face of the main portion 31 is also provided with a shorter tubular projection 35 located next to the projection 33 adjacent to the larger section 32 and having therein a hexagonal cross-section 36 to retain therein a hexagonal threaded nut (not shown) into which a screw may be inserted. The screw passes through the nut to engage the base of the box, in use, further rotation of the screw then driving the slider away from the base and so bringing the tab 34 into engagement with the reverse face of the plasterboard clamping the plasterboard between the tab 34 and the flange 5 so that, when both sliders are so positioned the box is held firmly in the opening and so will not be subject to movement, with consequent damage to the plaster and paintwork finish around it, when the electrical switch or socket, for example, is connected to the wires within the box. -5 -

The box shown in Figures 1 and 2 is further provided with mouldings 12 on the end walls 3 in which captured threaded nuts (not shown) permit attachment of the electrical devices instead of using the projections 33 on the sliders. This may be desirable, for example, where the box is installed close to a portion of the timber framework in the wall, preventing the insertion of the slider. In such a circumstance, the box can be installed after rotation through 90 degrees, with the sliders at the top and bottom instead of the sides, and with the switch or socket connected in the conventional orientation by screwing into the nuts within the mouldings 12. -6 -

Claims

CLAIMS1. A pattress box comprising a base, an open face surrounded by an outwardly-directed flange extending in a plane parallel to the plane of the base, an opposed pair of side walls extending between the base and the flange, each side wall having an aperture therein for receiving a respective slider, said aper-ture opening through the base, each slider having a main portion for sliding engagement with the aperture, a tab projecting from a first face of the main portion through said aperture to extend parallel to the flange, in use, and a projection from the opposite face of the main portion providing a screw threaded socket engageable by a screw which in turn bears on the base of the box, whereby rotation of the screw causes movement of the tab towards or away from the flange.
2. A pattress box according to Claim 1, wherein a further projection from the opposite face provides a second screw-threaded socket engageable by a fixing screw of an electrical device.
3. A pattress box according to Claim 2, wherein the further projection is in the form of a tube engageable with a cut-out in the base opening from said aperture, engagement of the tube with the cut-out serving to guide and locate the slider in the aperture.
4. A pattress box according to Claim 1, 2 or 3, wherein a further spaced pair of walls extend from the base to the flange at right-angles to and connecting the side walls.
5. A pattress box according to Claim 4, each of said further walls mounts a screw-threaded socket engageable by a fixing screw of an electrical 25 device.
6. A pattress box according to any preceding claim, wherein each slider is formed as an integral plastic moulding and the or each threaded socket is formed from a hexagonal threaded nut secured in said moulding.
7. A pattress box according to any preceding claim, wherein the main portion of each slider has a pair of offset larger sections for engagement with inner surfaces of the side walls whereby the main portion slides in the plane of the side wall or parallel thereto.