GB2119181A - Adaptor unit for an electrical accessory mounting box - Google Patents

Abstract

An adaptor unit for attachment to an electrical accessory mounting box (not shown) comprises a frame 50 having securement formations 81, 82 for affixing the frame to switch or outlet retainers of an electrical accessory mounting box. The frame has also location-facilitating means 61, 62, 63, 64 and 70, 72 respectively for providing positive location of the frame within an aperture in an apertured sheet or board. <IMAGE>

Description

SPECIFICATION Electrical accessory mount The invention relates to boxes for so-called flush mounting of electrical accessories such as switches and outlets.

The invention arises from our previous proposals in patent applications nos. 8136260 and 8136261 to provide advantageous mounting boxes capable, inter alia, of ready fitment to plasterboard or the like. Those prior proposals included provision of outwardly extending wall parts locatingly to engage in indentations of sides of holes into which the boxes were to be fitted; and also anchor parts movable substantially only parallel to the box base, or about an axis substantially perpendicular to the box base, in extending and retracting to and from protrusion through sides of the box. Those proposals are particularly well adapted to embodiment via suitable stamped metal blanks subsequently folded to shape.

Either or both of the above proposals provide substantial advantages by their ease of installation and we now propose extension of such advantages to existing or similarly conventional mounting boxes by way of attachments to said existing boxes to provide such extending and/or movable parts.

We find it particularly advantageous to do so as a frame-like adaptor, preferably generally resembling a box as previously proposed but minus base and having lugs to affix to the normal switch or outlet retainers, namely screw posts or lugs, of the existing or similarly boxes. Then, of course all said attachments for each existing box are connected together as a single unit.

One such preferred embodiment has a frame that overfits the open top of an existing or similarly conventional box with at least marginal exterior overlap on the walls of the existing box below any movable anchor parts of the adaptor unit.

Practical implementation of the invention will now be described, by way of example, with reference to the accompanying drawings in which Figs. 1 and 2 show perspective views of adaptor frames hereof.

In Fig. 1 the adaptor frame is referenced 50 and is rectangular with four walls 51, 52, 53, 54 shown with bends at corners 55, 56, 57 and secured by a spot-welded tab 59 at corner 58, actually shown in a joggled end 60 of the wall 51 to ensure a flush interior best suited to fitting over and about the open top of a standard mounting box (not shown).

Interlocking tabs could, of course, be used instead of the spot-welded tab 59.

Above the bends 55 to 58 upward sloped cuts of the original blank ensure that, at bending, parts 61, 62, 63, 64 project from ends of the walls 51 to 54, respectively, having been turned out of the other ends of the walls 52, 53, 54, 51 respectively, as indicated at 65 to 68.

One opposing pair of the walls (51 and 53) carry movable parts 70, 71 in the form of swivelling lugs having hooked end portions (see 72) housed in slots 73, 74 through the walls 51, 53 for hinging purposes. The parts 70, 71 also have anchoring ears 75, 76 movable from retraction to extension through holes 77, 78 in the side walls 51, 53. The parts 70, 71 further have, between their hooked end portions and anchoring ears, bent-over screw locator formations 79, 80.

Centrally of the other opposing pair of the walls (52 and 54) are securement formations as inward lugs 81, 82 with screw locator formations, conveniently actually clearance holes 83, 84 for screws to secure the adaptor frame 50 to an existing electrical accessory mounting box having threaded anchoring screw locator formations registering with the holes 83, 84.

It will be apparent that the interior dimensions of the bottom part of the frame 50 should accommodate the exterior dimensions of existing or similarly conventional accessory mounting boxes with any desired clearance, or as necessary to ensure accommodation of a desired range or variety of existing or similarly conventional mounting boxes. Moreover, the height X of the undersides of the lugs 81, 82 above the bottom of the frame 50 should be at least equal'to the height Y of the bottoms of the slots 73, 74 also above the bottom of the frame 50 to allow easy operation of the anchor parts 70,71.

Good initial location of a box fitted with a frame adaptor 50 is achievable by way of the blade-like projecting parts 61 to 64 on lightly tapping the box-adaptor combination home into a not-too-oversize accommodation hole, say in board such as plasterboard. Anchorage into or behind sides of such an accommodation hole is further readily achieved by swivelling the lugs 70, 71 from retraction to extension whereat they are securely maintained by screwing down the electrical accessory concerned.

It will be appreciated that all but X of the height of the adaptor frame 50 will be above the normal height of the associated accessory mounting box. At least for hollow wall constructions, typically of stud and board form, such increased height will rarely, if ever, produce problems. However, and perhaps particularly for use on solid walls, the proposed adaptor 50 could lead to making accessory boxes that are shallower than hitherto normal, and such, at least in combination with our adaptor frames or equivalent, are considered properly to be within the scope of this invention.

It should be clear that projecting parts such as 61 to 64 do not need to 'be at all four corners, nor do they need to be of straight tapered shape. Also, at least if only their location function is desired, such projecting parts do not need to be located above the height of an existing or similarly conventional box, see Fig. 2 where the only increase in height is the thickness of the lugs 81', 82' (at least for countersunk screws), see overlap height X', also lugs 85, 86 for accessory screw locators 79', 80'.

It is possible to use an incomplete frame adaptor say extending from say securing at 84 or 84' to include slots 73, 74 or lugs 85, 86. It is even possible to use only two corner parts, say one securing at 84 or 84' and the other at 83 or 83' and extending only to the slot 74 or the lug 86 and only to the slot 73 and the lug 85, respectively.

It is even feasible to dispense with using the accessory screw locators of existing or similarly conventional boxes solely, if at all for attachment of parts hereof. Thus, wall protruding parts could be screwed to sides of the box or interference fitted into holes therein or grippingly embrace over free edges thereof.

Swivelling lug carriers could be similarly dealt with, perhaps in combinations each with one or more wall protruding parts, and perhaps with clearance holes at 79, 80 to overfit screw locator formations of the box. There might have to be a relative inversion of the lugs themselves and adjustment of the height/relative heights of their bent over portions. However, swivelling lug carries would effectively be clamped in place at securement of the accessory to the box, i.e. sandwiched between them and coacting with or behind sides of the box accommodating hole.

Claims (14)

1. An adaptor unit for attachment to an electrical accessory mounting box comprising a frame having means for affixing said frame to switch or outlet retainers of an electrical accessory mounting box, and means for facilitating location relative to an apertured sheet or board.

2. An adaptor unit as claimed in claim 1, wherein said frame is adapted to overfit an open top of an electrical accessory mounting box with at least marginal exterior overlap on the walls of the mounting box below any said location-facilitating means carried by said frame.

3. An adaptor unit as claimed in claim 1 or 2, wherein said affixing means comprise inwardly directed securement formations on at least one of opposed pairs of side walls of the frame, said securement formations each having a screw locator formation to take an accessory fitting screw.

4. An adaptor unit as claimed in claim 1 or 2, wherein said location-facilitating means comprise a part or parts of said frame which extend outwardly from its side wall over at least part of the height of the side wall to engage an indentation or indentations of a side or sides of an aperture in said apertured sheet or board into which the frame is to be fitted thereby providing positive location relative to the aperture.

5. An adaptor unit as claimed in claim 4, wherein the part or parts are capable of at least partially forming corresponding indentations during initial fitting of said frame.

6. An adaptor unit as claimed in claim 4 or 5, wherein at least two such parts are spaced to be on opposing side wall portions of said frame.

7. An adaptor unit as claimed in claim 4, 5 or 6, of rectangular configuration, wherein at least two corners have one wall extend beyond the corner to present a said part.

8. An adaptor unit as claimed in claim 7, wherein the at least two corners are diametrically opposed relative to each other.

9. An adaptor unit as claimed in claim 7, wherein the said part is tapered with an upward slope.

1 0. An adaptor unit as claimed in claim 1 or 2, wherein said location-facilitating means comprise anchor parts movable about an axis substantially parallel to or coplanar with a side wall or walls of the frame in extending and retracting ears to and from catching protrusion through side walls of the frame.

11. An adaptor unit as claimed in claim 10, wherein a said anchor part is hinged to the side wall of the frame via interengagement of suitable formation of the frame at or adjacent its side wall and a portion of said anchor part.

1 2. An adaptor unit as claimed in claim 11, wherein said portion is an end portion spaced from the ear.

1 3. An adaptor unit as claimed in claim 10, 11 or 12, wherein said part further has a screw locator formation to take an accessory fitting screw, such screw locator formation being between the ear and said spaced end portion.

14. An adaptor unit as claimed in claim 1 3, wherein the parts are mounted to the frame at opposite sides thereof so that the screw fitting action is such as to aid said protrusion of the ears.

1 5. An adaptor unit as claimed in any one of claims 10 to 14, wherein said parts have bent-over end portions to cooperate with slots below the tops of the frame side walls for said hinging ear and any screw locator formation portions being bent over oppositely from top edges of said parts.

1 6. An adaptor unit as claimed in any one of the preceding claims of rectangular configuration with at least one corner secured by spot-welding of interlocking tabs.

1 7. An adaptor unit substantially as here it before described with reference to and as illustrated in the accompanying drawings.

1 8. The combination of an electrical accessory mounting box with an adaptor unit as claimed in any one of claims 1 to 17.