GB2190802A

GB2190802A - Electrical accessory mounting box

Info

Publication number: GB2190802A
Application number: GB08711516A
Authority: GB
Inventors: Hugh Jonathon Gearing
Original assignee: Ranton & Co Ltd
Current assignee: Ranton & Co Ltd
Priority date: 1986-05-23
Filing date: 1987-05-15
Publication date: 1987-11-25
Anticipated expiration: 2007-05-15
Also published as: GB8711516D0; GB8624840D0; GB2190802B; GB8612666D0

Abstract

An electrical accessory mounting box comprising a base (12) with side-walls (14) thereabout, an open top (16), and an angled hole (22) for receiving an elongate fixing member (eg screw) operative at an acute angle to the base and out past a side-wall. Frangible attaching members (34) hold the box flush by temporary fixing (at 38) to normal accessory attachment provisions (30) before permanent fixing of the box by driving a fixing member through the hole (22). <IMAGE>

Description

SPECIFICATION Electrical accessory mounting box This invention relates to mounting boxes for mains electrical accessories.

Two basic types of such mounting boxes comprise one for surface fixing to carry an accessory proud of a mounting surface usually of a wall or ceiling, and another for so-called flush fixing where the box is inset and an accessory plate abuts a surrounding surface again usually of a wall or ceiling. Both types are usually provided with a screw holes or knock-outs for fixing through their base to said surface or to the bottom of a recess formed in a solid wall or a block installed in a hollow wall. A third type of mounting box specifically for hollow walls has extensible and retractable means for location relative to sheet or board, typically plasterboard, about a hole cut to take the main body of the box.

It is an object of this invention to make useful additional or alternative fixing provisions for mains electrical accessory mounting boxes.

According to this invention, an electrical accessory mounting box having a base with side-walling thereabout and an open top, is further provided with a formation affording location for fixing by an elongate member, usually a screw, even nail, or the like, directed at an acute angle to the base and out past the side-walling, for the purpose then of being able to engage into a surface extending alongside such side-walling and beyond the base (or into a surface behind the base but at said acute angle).

It is found convenient for the formation to direct a screw etc out of the box at or close to a corner between the base and the side walling, also for the acute angle to be up to about 60 degrees but not less than where extension of said direction just clears the free edge of the side walling, about 45 degrees (perhaps t 15 degrees) being well-suited to starting a screw off by tapping before driving in the usual way.

If desired, or required, of course, say by the depth of a substantially rectangular box relative to its width, e.g. or applies to narrow archetrave accessories, a preferred acute angle could require the formation to give the screw etc an exit part way up the side-walling.

It will be evident that boxes hereof are well adapted to fixing wherever there is timber alongside the box position and of greater depth than the box. Thus, fixing into hollow wall structures next to a frame member or a ceiling next to a joist or like member for flush fitting of electrical accessories is particularly advantageous.

However, for facilitating such fixing, particularly setting the open top of a box at or below the wall or ceiling surface and/or in countering any tendency for the box to be drawn down into the wall or ceiling by the action of its fixing screw, it is further preferred herein for boxes hereof to have associated therewith at least one member, conveniently two, by which entry of the box into the hollow wall or ceiling void is limited as the box is fixed in place. Such member or members may be of plate-like form and have holes whereby a normal accessory fixing screw or screws can hold it or them at a suitable position extending across the box and beyond its side-walling. Such members are disposable after use, and, for a box of moulded plastics material, may be formed as break-off items relative to the box proper.

Electrical accessory mounting boxes need to afford a hole for mains cable entry purposes.

Such a hole may comprise, or arise from, a piercable or knock-out formation in the base of the box or even one of the sides. Electrical wiring regulations are such that the outer sheathing of mains cable must extend into the mounting box, i.e. sheathing must not be stripped back to such an extent that the internal wires, even though usually insulated, are located outside the box. With boxes of minimal dimensions, such as boxes for architrave fixing as described hereinbefore, space requirements dictate accurate stripping or possible breach of the regulations. This problem is overcome by forming a tubular extension around said hole which extends away from the box, thus keeping box dimensions to the minimum, whilst minimising material content of the box.Thus, there is proposed an electrical accessory mounting box having a base with side-walling thereabout and an open top, said box having cable entry provisions thereto in the form of a hole in the base or side-walling which hole is surrounded by a tubular sleeve extending outwardly from the box.

Preferably, the hole is in the base, conveniently oval or eliptical in shape. It is preferred that the box be made as a plastics moulding and provided with fixing provisions and other features according to requirements such as described hereinbefore or more generally.

Specific implementation of this invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a top plan view; Figure 2 is a bottom plan view; Figure 3 is an end view; Figures 4 and 5 are sections on lines X-X and Y-Y of Figures 1 and 2, respectively; and Figures 6, 7 and 8 are respectively a bottom plan view, an end view and a section on line Z-Z of Figure 6 of an electrical accessory box having a tubular extension to the cable entry.

In the drawings, an electrical accessory box 10, comprises a base 12 and side-walling 14 extending to an open top 16. As shown, the box 10 is generally rectangular with opposite long sides 14A, 14B and short sides or ends 14C, 14D, but the invention is applicable to other shapes, though preferably with one side straight or flatted at the position of a formation 20 for facilitating fixing relative to a surface flanking the side-walling (14B) at that formation 20.

The formation 20 has a hole 22 from inside to outside of the box 10 and directed at an acute angle to the base 12 to guide a fixing screw at such direction and angle, shown exiting the box at its side walling (14B) close to the base 20, though it could clearly be differ entiy disposed if desired, say higher up the side-walling of a deeper box. As shown, for a box 10 moulded from plastics material, the formation 20 is conveniently a slope-topped boss with a countersink 24 for screw accommodation. A medial position along a side wall of a rectangular box 10 is convenient, actually shown substantially central of its length.

The box is also shown with accessory fixing screw retainer posts 30A, 30B upstanding at suitable spaced positions from its base 12, and same may, if desired, contain a tapped block, say at position 32 (Figure 5), to receive and hold an accessory fixing screw. For fixing of the box 10 in a hole in a hollow wall next to a frame member (not shown, but clearly to be adjacent to side wall 14B as illustrated), a member (34) may be temporarily associated with each accessory fixing screw in its post 30A, 30B, each such member (34) having a length greater than the width of the box 10 and being apertured (36) for passage of a fixing screw.Then each such member (34) can be arranged to extend beyond sides of the box 10 in or at a desired spacing from its open top 16, and so serve to locate the box at a desired inset position relative to a hole in a hollow wall or ceiling facing sheet (by abutment on the latter adjacent the hole). Thereafter, fixing of the box 10 to an adjacent surface, typically of a timber wall or ceiling frame member, is readily achieved by a screw through the hole 22. It is actually preferred for each member 34 to have its hole 36 in a post 38 to set a minimum position of a plate-like member 34 corresponding to flush fixing.

Two members 34A, 34B are shown, each to be associated via accessory screws with the posts 30A, 30B not necessarily respectively. As shown, those members 34A, 34B are snap-offs from the box 10, see thinnings 40A, 40B (Figures 3 and 4), and are disposable items after fixing the box 10 in place.

Lastly, we advert to a hole 42, which could be a piercable or knock-out formation in well known manner, in the base 12 for mains cable entry purposes; also alternative base fixings 44A, 44B shown as having knock-outs or piercable skins at 46A, 46B, and an earth block location 48 in a base thickening 50 adjacent to one of the accessory screw posts (30B in the illustration) but alternatively the other (30A) as shown dotted at 48'. Also proposed is a web 45 between the post 30A and the side wall 14B and having a slot 47 to receive the shank of a wood screw during carriage/storage.

Referring to Figures 6, 7 and 8 there is shown another embodiment of electrical accessory box having a tubular extension to the cable entry provisions. In the illustrated embodiment the box has other features common to Figures 1 to 5 described hereinabove the description of which is also relevant to this modified embodiment and like reference numerals have been employed to denote corresponding parts.

The modifications resides in the provision of a tubular sleeve 60 which extends from the base 12 of the box and surrounds the hole 42 therein. Thus, the sleeve extends outwardly from the box and mains wiring is led into the box by way of the sleeve. This enables wiring regulations regarding sheathing to be met more easily whilst allowing minimum dimensions for the box itself.

A web 62 is illustrated as extending from one side of the sleeve to the base of the box Thus aids reinforcement as well as being provided principally as a moulding convenience.

Also shown in the drawings of Figures 6 to 8, but equally applicable to the embodiment of Figures 1 to 5 are modified posts 38 which, as illustrated are slotted from the free end with a parallel or tapered slot 66 diverging to the free end, to hold a retaining screw parallel the the wings at least in carriage/storage of the box. Said screws being employed for the fitting of said wings on assembly and/or for the fitting of an accessory to the accessory box.

Claims

1. An electrical accessory mounting box comprising a base with side-walling thereabout and an open top, and further comprising a formation affording directional location for fixing by an elongate fixing member operative at an acute angle to the base and out past the side-walling.

2. An electrical accessory mounting box according to claim 1, wherein the formation affords a said acute angle of up to 60 degrees.

3. An electrical accessory mounting box according to claim 1 or claim 2, wherein the formation affords a said acute angle of about 45 degrees.

4. An electrical accessory mounting box according to any preceding claims, wherein the formation affords exit for said elongate fixing member at or close to a corner between the base and the side-walling.

5. An electrical accessory mounting box according to any preceding claim, comprising an associated member or members to serve in limiting entry of the box into a mounting hole therefor.

6. An electrical accessory mounting box according to claim 5, wherein the or each said member extends or can extend beyond the side-walling at the open end of the box.

7. An electrical accessory mounting box according to claim 5 or claim 6, wherein the or each member is temporarily affixable to the box by way of normal accessory attachment provision of the box.

8. An electrical accessory mounting box according to claim 7, wherein the or each member is so affixable by normal accessory mounting screws through a hole in that member.

9. An electrical accessory mounting box according to any one of claims 5 to 8, wherein the or each member is of plate-like form.

10. An electrical accessory mounting box according to any one of claims 5 to 9, wherein the or each member is removably associated with the box as supplied.

11. An electrical accessory mounting box according to any one of claims 5 to 10, wherein the or each member is removably associated with the box by way of break off formations.

12. An electrical accessory mounting box according to any preceding claim, further comprising cable entry provision associated with an insulated sleeve in fixed relation to and extending from the box.

13. An electrical accessory mounting box according to claim 12, wherein the sleeve so extends substantially at a right angle.

14. An electrical accessory mounting box according to claim 12, or claim 13, wherein the sleeve is about a hole in the base of the box.

15. An electrical accessory mounting box according to claims 12, 13 or 14, wherein the sleeve is formed integrally with the box.

16. An electrical accessory mounting box according to any one of claims 12 to 15, wherein the sleeve is of oval section.

1 7. An electrical accessory mounting box substantially as herein described with reference to and as shown in Figures 1 to 5 or Figures 6 to 8 of the accompanying drawings.