GB2176886A

GB2176886A - Construction of electrical devices

Info

Publication number: GB2176886A
Application number: GB8515821A
Authority: GB
Inventors: Geoffrey Williams; Bromley Dixon
Original assignee: TRIDENT LIGHTING Ltd
Current assignee: TRIDENT LIGHTING Ltd
Priority date: 1985-06-21
Filing date: 1985-06-21
Publication date: 1987-01-07
Also published as: GB8515821D0; GB2176886B

Abstract

An electrical device, for example a lamp (32) comprises a tubular part (39) through which an electrical cable (46) may pass to a bulb holder (42) mounted on one end of the tubular part (39). The other end (40) of the tubular part (39) is flattened and is secured in a quick and simple manner by means of a rivet (41) to a plate (38). An aperture (47) is provided in the tubular part (39) adjacent the flattened end (40) to allow the cable (46) to enter the tubular part (39). A cover (48), through which the tubular part (39) passes, encloses the plate (38) which is mounted on a support tube (33). <IMAGE>

Description

SPECIFICATION Construction of electrical devices This invention relates to the construction of electrical devices, and in particular to the construction of such devices in which an electrical appliance is mounted on an arm along which an electrical cable is passed.

Conventionally such an arm is formed of a tube whereby the electrical cable can pass along the tube and be hidden from view. In addition the tube affords protection for the cable against damage, thereby reducing the risk of short circuiting and/or the receiving of shocks from the appliance by anyone touching it. In order to attach the tube to the appliance and/or to a mounting device it is conventional to pass a screw-threaded end of the tube through a plate or wall-like member of the appliance or mounting device and provide either a nut on either side of that member, or a nut on one side and a shoulder or abutment on the tube at the other side of that member against which that member is located. However the provision of the screw-thread on the tube and the subsequent assembly of the various parts are time consuming and costly steps in the production of the device concerned.

In an attempt to overcome these problems it has been proposed to deform at least two adjacent parts of the plate-like member to opposed sides of the plate to provide a collar formation thereby. The arm is then inserted through the collar portion and secured by a grub-screw. This method of construction has only alleviated the abovementioned problems to a limited extent, and it is an object of the present invention to provide a method of construction which reduces to a greater extent than has been possible heretofore the abovementioned problems.

The invention provides an electrical device having a tubular part along which an electrical cable may pass, and a plate-like part of the device to which the tubular part is secured, wherein an end of said tubular part is flattened, said flattened end is secured to said plate-like part in face-to-face disposition and an aperture is provided in said tubular part adjacent said flattened end through which an electrical cable may pass from the exterior to the interior of said tubular part.

The flattened end may be secured to said plate like member by passing securing means thereth rough. Said securing means may comprise at least one rivet.

The electrical device may be a lighting unit com prising a lamp part and a mounting part, and hav ing a tubular part through which an electrical cable may pass, said tubular part extending between said lamp part and said mounting part.

Embodiments of electrical devices constructed in accordance with the invention will now be described with reference to the accompanying draw ings in which: Figure 1 is a perspective view of part of an electrical device incorporating the invention, Figure 2 is a side elevation of one embodiment, and Figure 3 is a sectional, exploded elevation of a second embodiment.

Referring now to Figure 1 there is shown a part of an electrical appliance 10 which comprises a tube 11 along which an electrical cable 12 passes.

The end 13 of the tube 11 is flattened and is secured to a plate 14 by means of a rivet 15 passing through the double-walled flattened end 13 and the plate 14. Adjacent the flattened end 13 is an aperture 16 in the tube 11 through which aperture 16 the cable 12 passes into the interior of the tube 11.

The aperture 16 is created by forming a slit in the tube 11 transversely of its axis around substantially half of its perimeter a short distance from the end of the tube 11. The tube part 13 between the end of the tube and the slit is then flattened, the remainder of the tube 11 remaining in its original configuration, e.g. circular. The plate 14 and the flattened end 13 of tube 11 are then drilled and rivetted together.

Referring now to Figure 2 there is shown an electrical appliance in the form of a lamp 20 adapted for mounting on a wall 21. The lamp 20 comprises a mounting plate 22 which is secured to the wall 21 by screws 23 and has a hole 24 therethrough, through which an electrical cable 25 passes after emerging from being embedded in the wall 21. A tube 26 is secured to the plate 22 by means of a rivet 27 passing through the plate 22 and the flattened end 28 of the tube 26 in the manner described in relation to Figure 1. The tube 26 forms an arm on the end of which is a bulb holder 29 by means of which a bulb and lamp-shade (not shown) are mounted in conventional manner. The electrical cable 25 enters the tube 26 through the aperture 30 and passes along the tube 26 to the bulb holder 29. A cover 31 is provided, secured to the plate 22 and through which the tube 26 passes.

Referring now to Figure 3 there is shown a lamp 32 of the suspended type. The lamp 32 comprises an outwardly screw threaded support tube 33 on the bottom end of which is a retaining nut 34 and on the top end of which is a second retaining nut 35. A ring 36 is retained by the nut 35 so that the lamp 32 may be suspended from the ceiling by means of a cord, chain, hook or the like. The support tube 33 passes through a central aperture 37 in a circular plate 38. A number of arms 39 are secured to plate 38 adjacent the periphery thereof with equi-angular relative disposition, in the embodiment shown three such arms 39 are provided at 120 spacing around the plate 38. Each arm 39 is formed of a tube having one end 40 thereof flattened and secured to the plate 38 by means of a rivet 41 in the manner previously described.At the outermost end of each arm 39 is a bulb holder 42.

A mid-portion of the support tube 33 is deformed and an aperture 43 is provided therein to enable a main electrical cable 44 to pass downwardly through the upper part of support tube 33 and out of the aperture 43. Connectors 45 are provided to connect the main cable 44 to three subsidiary electrical cables 46, each of which passes along a respective tubular arm 39 to the respective bulb holder 42, the cables 46 entering the arms 39 through apertures 47 adjacent the flattened ends 40 of the arms 39. Upper and lower cover members 48 are retained on the support tube 33 by the retaining nuts 34, 35 to enclose the plate 38, connectors 45 and arm ends 40, semi-circular recesses 49 being provided around the peripheries of each cover member 48 to provide apertures for the arms 39 to pass through on assembly of the lamp 32.

The construction of the electrical devices 20,32, whereby the tubular arms 26,39 are secured to a plate 22,38 in the manner herein described in relation to and as illustrated in Figures 1 to 3, may be employed at the other end of arms 26,39 if desired.

For example in the event that a lamp shade of metal or other rigid material is used, to which a bulb holder is connected, the arms 26,39 may be secured directly to the lampshade in the manner in which they are secured to the plates 22,38.

By means of the invention electrical devices may be constructed in a simple and quick manner, thereby reducing manufacturing costs. Alternative embodiments will be readily apparent to persons skilled in the art. For example instead of rivets being used, bolts or spot welding may be used to secure the tubes to the plate.

Claims

1. An electrical device having a tubular part along which an electrical cable may pass, and a plate-like part to which said tubular part is secured, wherein an end of said tubular part is flattened, said flattened end is secured to said plate-like part in face to face disposition, and an aperture is provided in said tubular part adjacent said flattened end through which said electrical cable may pass from the exterior to the interior of said tubular part.

2. An electrical device according to claim 1 wherein said flattened end is secured to said platelike part by passing securing means therethrough.

3. An electrical device according to claim 2 wherein said securing means comprises at least one rivet.

4. An electrical device according to any one of claims 1 to 3 being a lighting unit comprising a lamp part, and a mounting part comprising said plate-like member, wherein said tubular part extends between said lamp part and said plate-like member of said mounting part.

5. An electrical device according to claim 4 wherein said mounting part is adapted to be secured to a wall.

6. An electrical device according to claim 5 comprising a cover attached to said mounting part and through which said tubular part passes.

7. An electrical device according to claim 4 wherein said mounting part comprises a support tube, said plate-like member being mounted on said support tube.

8. An electrical device according to claim 7 comprising a plurality of tubular parts secured to said plate-like member equi-angularly spaced therearound and along each of which a respective electrical cable may pass to a respective lamp part mounted on the end of each tubular part remote from said plate-like member.

9. An electrical device according to claim 7 or claim 8 wherein said support tube is adapted to be dependably attached to a ceiling or roof.

10. An electrical device according to claim 9 wherein said support tube has a nut retained thereon, said nut having a ring secured thereto whereby said device may be suspended from a ceiling or roof by means of a cord, chain or hook.

11. An electrical device according to any one of claims 7 to 10 comprising a cover retained on said support tube and within which cover said plate-like member is disposed.

12. An electrical device substantially as hereinbefore described with reference to and as illustrated in Figures 1, 2 or 3 of the accompanying drawings.