GB2243960A - Building block for electrical fitting - Google Patents

Abstract

A building block (1) suitable for building into a wall or partition, in which a recess (2) is preformed. The recess (2) is of a standard size to receive standard sized electrical fittings such as sockets or switches which are secured into the recess by means (3) provided in the recess. Channels (5) may be provided in a surface of the block to receive cables extending from cable runs beyond the block and into the recess (2). The means for securing the electrical fittings are preferably formed as a metal frame in which are screw holes (3), the frame being moulded into the area (11, 12) around the recess. Preferably this area (11, 12) stands proud of the front surface (13) of the block. The frame includes knockouts for the cables. <IMAGE>

Description

A BUILDING BLOCK The present invention relates to a building bloc for mounting an electrical fitting.

During construction or modification of a building where electrical fittings such as sockets or switches have to be mounted, the normal practice is to complete the brick or blockwork, then cut recesses for the fittings and chase out where necessary runs for cables. This is expensive and is frequently done with a high degree of inaccuracy.

Metal mounting boxes for flush mounting have to be inserted in the recesses and the gap between the recess walls and box walls fitted flush with mortar at the same time rechecking the accuracy of alignment of the box.

According to the present invention there is provided a building block having a recess adapted to receive an electrical fitting at least two walls being provided with means for receiving screws or other fixing means provided for securing or being a part of the electrical fitting.

The building block of the invention having a preformed suitable recess need only be built in and aligned in a wall or partition in the same action as other blocs so that the recess is correctly aligned as the wall is built. When the wall is finished the normal steps of fixing cable runs in place, rendering the wall and plastering the render is carried out so that the switches and sockets can be simply fixed into the recess. The result is accurate and saves time.

Preferably the recess has moulded into it a screw receiving metal frame such as a panel mounting metal frame sold by MK Electric Ltd. under their list number 2200 Z1C or 2202 ZIC. These plates have threaded screw holes already formed at the correct standard locations for switches and sockets. Advantageously the immediate area around the recess or perimeter of the recess is formed as a surround to stand proud of or raised from the surrounding surface of the block so that render and plaster can be wiped up to the recess and then levelled with the exposed edges of the recess. This surround may be re-formed integrally with the block or be separate. In the case of a separate surround this is provided with the means for receiving screws or other fitting means.Cable channels can also be formed in the surface of the block up to or immediately adjacent the recess with, if required break away terminations in the channels which enable access for cable to the interior of the recess from the run. The block may have intrusions or frogs in the surfaces which are to be mortared into the wall so as to assist bonding with other wall blocks. The block may also have further holes or recesses particularly in the face opposite the entry into the recess and may be hollow so as to reduce the volume of the block material.

Suitably the block is a modular size equal or a common fraction of the size of a standard building block. The material of this block ought to be suitable for keying with the mortar used for known blockwork.

Embodiments of the invention will now be described with reference to the accompanying drawings in which: Figure 1 is a perspective view of a building block according to a first embodiment of the invention and Figure 2 is a cross section of the block of Fig. 1 taken at AA.

Figure 3 is a cross section of a second embodiment of a building block according to the invention and, and Figure 3A is a cross-section of a surround for fitting into the block of Fig. 3.

In Figures 1 and 2 the drawings a building block 1 formed of a plastics resin is provided with a recess 2 of a size approximately 75 x 135 mm suitable to take a two gang socket. However, this size can be 75 x 75 mm for a single gang socket or switch or any other standard size.

Threaded holes 3 are provided at standard spacings around the inside of the recess in a metal frame 10, suitably a panel mounting frame made by MK Electric Ltd. under list No. 2202 ZIC (for a double gang recess).

The perimeter 4 of the recess has a flat raised surface 11 around it extending to a sloped portion 12 which ramps down to a front surface 13 of the block. The sloped portion and raised surface together act to assist in wiping and or levelling render and plaster finish with surface 11.

Wiring channels 5 are formed in surface 13 and these terminate at 15 short of the recess but which are provided with weakened areas so they can be broken to run cables or wiring into the recess.

Slots or frogs 6 are provided in sides 16 to provide keys for mortar to join the block to other wall or building blocks. Lightening holes 7 are provided in the rear wall 17 if required. The block itself is formed with a hollow 18 providing a suitable material is used for the block.

In Figures 3 and 3A a second embodiment is shown in which a building block 21 is formed of concrete or breeze. The block is of a similar shape and size to block 1 with frogs 26 in sides 36 but is solid. Wiring channels 25 are also provided in front surface 33, but these terminate openly in open recess 22 moulded in front surface 33. A separate surround 40 for the recess is formed of plastics material having a perimeter 24 with a flat raised surface 31 around it extending to a sloped portion 32 which ramps down to the front surface 33 of the block in a similar manner and for the same pupose as perimeter 4 of block 1. The surround 40 has moulded into it a metal frame 30 in which threaded holes 23 are provided as in the first embodiment. The surround has walls 41 in which are flexible sprags 42 which spring outwards into the walls 43 of recess 22. The surround 4U also has a base 44. Weakened portions 45 in the walls 41 of the surround align with channels 25 and these portions can be broken out to enable cables in a selected channel 25 to enter the interior of the recess 22 within surround 40.

Claims (9)

1. A building bloc having a recess adapted to receive an electrical fitting, at least two walls being provided with means for receiving screws or other fixing means provided for securing or being a part of the electrical fitting.

2. A block as claimed in claim 1 wherein an immediate area around the recess or perimeter of the reccess is formed as a surround to stand proud of the surrounding surface of the block.

3. A block as claimed in claim 1 wherein a screw receiving metal frame is moulded into the block so that the frame extends around a perimeter of the recess.

4. A block as claimed in claim 2 wherein the surround is formed separately from the block wherein the means for receiving screws or fixing means is a part of or is attached to the surround.

5. A block as claimed in any one of claims 1 to 4 wherein cable channels are formed in a surface of the block up to or immediately adjacent the recess.

6. A block as claimed in claim 5 wherein the channels terminate adjacent the recess in portion which are arranged to be broken away to enable a cable to run from a said channel into the recess.

7. A block as claimed in any one of claims 1 to 5 wherein the block has intrusions in side surfaces to receive material for bonding to adjacent blocks.

8. A building block substantially as described with reference to Figures 1 and 2 of the accompanying drawings.

9. A building block substantially as described with reference to Figures 3 and 4 of the accompanying drawings.