GB2257847A

GB2257847A - Lid for electrical outlet boxes.

Info

Publication number: GB2257847A
Application number: GB9113425A
Authority: GB
Inventors: Alan Christopher Penfield; Derek Graham Mccarty; Michael Jones; Alan Robert Pond
Original assignee: MK Electric Ltd
Current assignee: Novar ED&S Ltd
Priority date: 1991-06-20
Filing date: 1991-06-20
Publication date: 1993-01-20
Anticipated expiration: 2011-06-20
Also published as: GB2257847B; GB9113425D0

Abstract

An electrical outlet box for raised floors is formed as a metal box in which electrical sockets (20) or switches can be mounted in the bottom; the box has a lid assembly (12) which is vertically adjustable relative the box by means of a pawl and ratchet arrangement (63). This arrangement enables rapid adjustment of the vertical distance between the lid and box so that different thicknesses of floor covering can be allowed for. The pawl bars (60) are spring-urged and held in place by a snap fit. Pawl release is effected by a handle on the pawl. <IMAGE>

Description

OUTLET BOXES The present invention relates to electrical outlet boxes for raised floors.

Outlet boxes for raised floors commonly comprise a metal box with suitable means to mount the box to a floor panel. The box has an open bottom into which several metal containers are fixed. Electrical sockets and/or switches are mounted in turn in the containers. The box is arranged to accept in its top a lid assembly which includes a main lid in which are cable outlet lids and a peripheral flange which extends around the assembly.

After mounting the box to the floor panel carpet is laid over the floor panel and around the box, the lid assembly is located over the box so that the peripheral flange seats on top of the carpet. Outlet boxes constructed with this arrangement in mind are shown in EP 0343754 Al, GB 2194975A and GB 1583946.

In order to allow for different thicknesses of carpet and floor panel material it is known to adjust the box height relative the floor panel and the lid assembly relative the outlet box. In GB 2194975 the fixture to and adjustment relative to the floor panel is by means of an angular section bracket screwed at each end to opposed vertical sides of the box with adjustment enabled by providing three holes at each end of a vertical web of the bracket.

In order to adjust the height of the bracket relative the box, the two screws are removed and reinserted in upper or lower pairs of holes. The carpet is then laid and the lid assembly is inserted in the box and is screwed down so that a flange around the assembly seat on top of the carpet. This is time consuming and furthermore as the carpet compresses during use the screws work loose. A further disadvantage is that during fitting the box which has no bottom tends to distort so that screw receiving brackets in the box misalign with the screws in the lid assembly causing further fitting difficulties.

Accordingly an electrical outlet box for raised floors according to the invention comprises a metal box with a means for lid assembly adjusting the height of the lid assembly relative to the box, the box being adapted to have mounted in the bottom thereof electrical sockets and/or switches, the box having means for adjustably securing the box to a floor panel characterised in that the means for adjusting the height of the lid assembly relative to the box comprises a pawl and ratchet arrangement between at least one side of the box and the lid assembly.

The advantage of the arrangement according to the invention is that the pawl and ratchet height adjustment arrangement enables the lid assembly to be quickly adjusted for height and furthermore the lid assembly can be quickly removed to take the box out and further as the carpet compresses during use the lid assembly is simply pushed further down into the box. The lid assembly which is generally rigid can easily be securely fitted into the box which is somewhat flexible.

Preferably the pawl and ratchet arrangment comprises at least one and preferably four ratchet means on the box sides. Preferably two ratchet means are on one side whilst two are on the other box side. Preferably there are two pawls on each side mounted to a simple pawl bar with a handle to pull the pawls out of engagement with corresponding ratchet means.

In a preferred embodiment the pawl bar is provided with a spring towards each end so that any lack of parallelism between the lid assembly and box may be taken up by the springs. Preferably the or each pawl is a ratchet with teeth facing opposite directions to teeth of the ratchet means.

An embodiment of the invention will now be described with reference to the accompaning drawings in which: Figure 1 is a perspective view of an outlet box according to the invention, Figure 2 is a perspective view of a lid assembly for the box of Fig. 1, Figure 3 is a cross section of the box of Fig. 1 with the lid assembly mounted in the top of the box, Figure 3A is an enlarged cross section of area A of Fig. 3 showing a pawl and ratchet arrangement, taken at CC of Fig. 4, Figure 4 is a cross section of a pawl bar for adjustably securing the lid assembly of Fig. 2 to the box of Fig. 1.

Figure 5 is an elevation of pawl bar of Fig. 4 seen from inside the lid assembly, Figure 6 is a plan view of the pawl bar of Fig. 4 seen from above, Figure 7 is an elevation of the pawl bar of Fig. 4 in a direction looking from the outside of the box into the centre of the box, and Fig. 8 is a cross section of the bar of Fig. 6 taken at BB.

In Figure 1 there is shown an electrical outlet box 10 for raised floors. The box has a lid assembly generally shown at 12 in Fig. 2, the box 10 has an open top 11 into which the lid assembly is fitted and which is retained by ratchet arrangements 14 as shown in Fig. 3. The box has an open bottom into which are fitted modular containers 18 in which are mounted electrical sockets 20, and/or switches (not shown). The box 10 has a means for adjustably securing the box to a floor panel 22 which comprises at least one and preferably two brackets 24 adjustably clamped to a side 26 of the box by a central clamping means or pan head screw 28 which is received by an indented threaded hole 30 in the side and preferably both sides 26 of the box.

The lid assembly comprises a lid frame or surround 52, a hinged lid 53 in which are hinged cable openings 54 for cable shown as a broken line 55 from a plug 56 in one of several sockets 20. A handle 59 us for opening the lid.

The ratchet arrangement 14 comprises two pawl bars 60 each with a first vertical row of teeth 62 and a second vertical row of teeth 63 towards each end of the bar.

Teeth 62 and 63 are each sprung by one pair of coil springs 65 onto a ratchet means formed by two horizontally spaced toothed ratchet surfaces 67 and 68 on each opposed side 70 of the box. The toothed surfaces 67, 68 can either be provided by forming portions of sides 70 by punching or else by attaching already formed toothed elements to the sides 70.

Springs 65 are each held between the pawl bar 60 and the frame 52 by means of a recess 57 in the frame and a protrusion 58 on the pawl bar. The pawl bar 60 is held in a recess 59 in the frame by means of a pair of hooked arms 61 engaging with inner sides of recess 64 of the frame through which handle 72 protrudes.

The teeth formed like saw teeth on toothed surfaces 67, 68 on box sides 70 face those of a similar form on bars 60 so that the scope of opposed teeth are in opposite directions in the sense that the box teeth slope downwards and the bar teeth slope upwards. This ensures that when frame 52 is pushed into box 10, the engaging teeth allow entry but prevent the frame escaping from the box. To remove the frame from the box it is merely necessary to pull centrally mounted handle 72 towrds the box centre to release the engagement of the teeth.

It will be appreciated that if side 70 of box 10 is not quite parallel to the opposed side 74 of frame 52, then the laterally separated spring 65 takes up any divergence in parallelism to ensure both sets of teeth 67, 62 and 68,63 fully engage to hold the frame 52 securely in box 10.

Details of the bracket arrangement 24 will be described in copending patent application number S}l3+ filed on the same date as the present application.

Claims

1. An electrical outlet box for raised floors comprising a metal box with a lid assembly, means for adjusting the height of the lid assembly relative to the box, the box being adapted to have mounted in the bottom thereof electrical sockets and/or switches, the box having means for adjustably securing the box to a floor panel characterised in that the means for adjusting the height of the lid assembly relative to the box comprises a pawl and ratchet arrangement between at least one side of the box and the lid assembly.

2. An outlet box as claimed in claim 1 wherein the pawl and ratchet arrangement comprises at least one and preferably four ratchet means on the sides of the box.

3. An outlet box as claimed in claim 1 or 2 wherein two ratchet means are one one side of the box and two ratchet means are on the other side of the box.

4. An outlet box as claimed in any one of claims 1 to 3 wherein there are a pair of pawl means on each side, each pair mounted to a single pawl bar having a handle to pull the pawl means out of engagement with corresponding ratchet means.

5. An outlet box as claimed in claim 4 wherein each pawl bar is provided with a spring towards each end of the bar to urge the pawl means into engagement with the ratchet means.

6. An outlet box as claimed in any one of claims 1 to 5 wherein the pawl and ratchet arrangement includes a pawl means comprising a plurality of teeth extending from a pawl bar

7. An outlet box as claimed in any one of claims 1 to 6 wherein the means for adjustably securing the box to a floor panel comprises at least one bracket adjustably clamped to a side of the box by a central clamping means, a protrusion and recess arrangement between the bracket and box side either side of the clamping means such that the protrusion and recess arrangment enables location of the bracket relative to the box side at several vertical positions.

8. An outlet box as claimed in claim 7 wherein the clamping means is a single screw inserted through a vertical slot in the bracket and received by a threaded portion of the box side or a nut locked to the box side.

9. An outlet box as claimed in claim 7 or 8 wherein the protrusion and recess arrangment is a protrusion from the bracket either side of a central vertical slot for the clamping means and a plurality of vertically spaced recesses which may be apertures in the box wall either side of the clamping means.

10. An electrical outlet box for raised floors substantially as described with regard to the accompanying drawings.