GB2376063A

GB2376063A - Lamp with reflector and gear housing

Info

Publication number: GB2376063A
Application number: GB0212373A
Authority: GB
Inventors: Norman James Poole
Original assignee: HILCLARE Ltd
Current assignee: HILCLARE Ltd
Priority date: 2001-05-29
Filing date: 2002-05-29
Publication date: 2002-12-04
Also published as: GB0112909D0; GB0212373D0

Abstract

A lamp comprising a gear or ballast housing 1 connected to a housing 2 for the light source (19, figure 3), the light source housing also functioning as a reflector. The gear may comprise an inductor, capacitor and starter for use with a flourescent tube. Preferably, an aluminium bracket 21, 22 is present on top of each housing for suspension of the lamp from a ceiling. Both housings are formed by folding single sheets of metal and the source housing is strengthened by a V-shaped channel 13 along its spine. It is closed by an end piece 3 secured by tabs 8 through holes 9. A diffuser may be mounted on a lip 10 on the source housing and secured by a bracket 6 with tabs 11 that engage more holes 12 in the source housing. The gear housing is strengthened by a cross bracket 4. The lamp is lightweight and conducts heat effectively, maintaining the source and gear at a lower temperature to run more efficiently.

Description

A LUMINAIRE.

The present invention relates to a luminaire and particularly, but not exclusively, to a luminaire suitable for medium and high powered horizontal discharge lamps.

Luminaires containing horizontally mounted medium and high powered discharge lamps are generally referred to as"Low Bays". These luminaires comprise a"gear pack"containing a heavy inductor used to stabilise the discharge, a capacitor and starter components, a lamp with socket, an aluminium reflector and a steel case. In some luminaires, the cavity containing the lamp and reflector is contained by a glass or plastic surface permitting the passage of light, referred to generally as a diffuser although this can be clear with no distortion. The inductor can weigh several kilos and in order to secure this weight safely a usual construction uses a steel case to hold all the components. This is a time consuming process and results in a heavy and expensive construction. An object of the invention is to mitigate these disadvantages.

According to the invention, there is provided a luminaire comprising a first housing for housing the lamp of the luminaire and second housing, connected to the first housing, for housing the gear of the luminaire in which the first housing also acts as a reflector to direct the light from the lamp.

In a preferred embodiment of the invention, the luminaire is adapted for use with horizontally mounted discharge lamps. Advantageously,

means are provided on the second housing for supporting the luminaire towards or at one end. Means are provided for supporting the luminaire at or towards the other end on the first housing. The first housing is formed at its lower edge to accommodate a diffuser. Preferably the formation comprises a ledge and preferably the diffuser is made from glass or plastics. Preferably the first housing is made from a first part of substantially semi-cylindrical shape and a second part of substantially semi-circular shape closing off the end of the first part remote from the second, gear, housing. Both parts are advantageously made from metal, preferably aluminium. The first housing is advantageously made from a flat sheet of metal, folded to present specific angles to a lamp running along the axis of the reflector to provide a predetermined distribution of light.

In order that the invention may be more clearly understood one embodiment thereof will now be described, by way of example, with reference to the accompanying drawings, in which :Figure 1 is an exploded view of a luminaire omitting electrical components, Figure 2 shows a luminaire of figure 1 assembled with electrical components, and Figure 3 is a cross-section through the luminaire of figure 2.

Referring to figure 1, the luminaire comprises a gear housing 1, an anodised aluminium reflector 2, and an end cap reflector 3. The gear

housing 1, is formed by bending a single steel sheet, which has been punched and cropped to the appropriate shape and is secured by two self tapping screws. All electrical components including cable and lamp holder are secured to this housing. The stability of the housing is enhanced by two brackets, 4 (only one of which is shown in Figure 1) secured between the sides of the housing one each just below supporting steel lugs 7.

The anodised aluminium reflector 2 is bent from a single stamped sheet to present specific angles to the lamp to generate the appropriate beam width. Similar structures having different angles can be designed to give narrower beams of light. There is a v-bend 23 along the spine to improve rigidity and strengthen the structure. The v-bend also serves to reduce light reflected straight back onto the lamp thereby increasing efficiency and reducing lamp temperature. The lower edges of the reflector are bent to form a ledge 10 to support a glass or plastic diffuser if fitted. The gear housing 1, slides into the reflector 2 supported by the ledge 10 and is secured by a self-tapping screw through a hole 13 into a hole 14. A steel bracket 5 is secured to the top of the reflector 2 by means of bolts inserted through holes 15. This bracket 5 contains two holes 21 in its vertical surface for the attachment of chain used to suspend the fitting. A corresponding chain is attached to holes 22 in the lugs 7 of the gear housing 1. Alternatively for surface mounting, specific

brackets are fixed to the ceiling and these in turn are secured to the four mounting holes 21 and 22.

The end-cap reflector 3 is also formed from a single aluminium sheet and comprises six tabs 8. These tabs are pushed through corresponding slots 9 in the reflector body 2 and are bent to secure the end-cap reflector 3 in place.

If a diffuser 20 is fitted, then it is slid into the reflector 2, resting on the ledge 10, until it abuts the gear housing 1. An end bracket 6 made from steel angle is then fitted. This comprises a corresponding ledge 10 to hold the end of the diffuser. It is fixed to the reflector 2 by inserting tabs 11 through corresponding slots 12 and bending.

The lamp holder 16 is fastened to the end of the gear housing 1 by means of the holes 17 and is connected to electrical components (not shown) comprising a choke, capacitor and starter if fitted. These components are located in the gear housing 1. The back face of the gear housing 1 contains a hole 18 through which cable passes for connection to the electrical power supply.

Almost all the weight of the luminaire is contained within the gear housing and this weight is supported from the two steel lugs 7 which are an integral part of the housing. At the other end of the reflector 2, the luminaire is balanced by securing the steel bracket 5 containing the two holes 21 for the purpose of securing chain or other fixings. This bracket 5 bears only a small part of the weight of the luminaire as its centre of

mass, dominated by the weight of the choke in the gear housing, lies close to the lugs 7.

Figure 3 shows a cross-section of the reflector 2 with a lamp represented by a circle 19. The angles of the reflector shown in figure 3 are suitable for a luminaire giving a wide angular distribution of light. The angles can be modified to give a luminaire with narrower beam width.

The bends running longitudinally along the reflector body define these angles, and additionally give rigidity to the reflector. This minimises twisting and bending such that a mechanically sound luminaire can be built with a reflector using a relatively light gauge of aluminium sheet.

The edges of the reflector are bent to form an angular ledge 10 which are used to support the diffuser 20 if fitted.

With the above construction no steel case is required to house the reflector as with conventional construction as the reflector itself provides the housing and the number of parts is therefore reduced. This has two main advantages. First, there is a reduction in cost of both materials and assembly with no loss of performance. Second performance is actually increased as the lamp and control gear runs cooler without the conventional steel case due to the improved heat dissipation.

It will be appreciated that the above embodiment has been described by way of example only and that many variations are possible without departing from the scope of the invention.

Claims

CLAIMS 1. A luminaire comprising a first housing for housing the lamp of the luminaire and second housing, connected to the first housing, for housing the gear of the luminaire in which the first housing also acts as a reflector to direct the light from the lamp.
2. A luminaire as claimed in claim 1, in which means are provided on the second housing for supporting the luminaire towards or at one end.
3. A luminaire as claimed in claim 1 or 2, in which means are provided on the first housing for supporting the luminaire towards or at one end.
4. A luminaire as claimed in claim 1,2 or 3, in which the first housing is formed at its lower edge to accommodate a diffuser.
5. A luminaire as claimed in claim 4, in which the diffuser is made from glass or plastics.
6. A luminaire as claimed in any preceding claim, in which the first housing is made from a first part of substantially semi-cylindrical shape and a second part of substantially semi-circular shape closing off the end of the first part remote from the second housing.
7. A luminaire as claimed in claim 6, in which both parts are made of metal.
8. A luminaire as claimed in claim 7, in which the metal is aluminium.

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9. A luminaire as claimed in any preceding claim, in which the first housing comprises a flat sheet of metal folded to present specific angles to a lamp running along the axis of the reflector to provide a predetermined distribution of light.
10. A luminaire as claimed in claim 9, in which a v-bend is formed in the first housing along its spine.
11. A luminaire substantially as hereinbefore described with reference to the accompanying drawings.