GB2092289A

GB2092289A - Improvements in or Relating to Lighting Fittings

Info

Publication number: GB2092289A
Application number: GB8101460A
Authority: GB
Original assignee: PME LIGHTING Ltd
Current assignee: PME LIGHTING Ltd
Priority date: 1981-01-17
Filing date: 1981-01-17
Publication date: 1982-08-11

Abstract

A shroud 7 for a lighting fitting comprises an outer member 23 and an inner member 24 having an aperture receiving a terminal mounting 15 of the fitting which is internally threaded for receiving the threaded end 9 of a fluorescent lamp 18, or is shaped for forming a bayonet connection with a lamp. The fitting may comprise a batten lampholder 12, 14 for securing to a ceiling 10. Threaded spacer 25 can be provided and threaded conical member 26 may hold the shroud in place. The inner member 7 could be longitudinally adjustable in relation to the outer member 23. <IMAGE>

Description

SPECIFICATION Improvements in or Relating to Lighting Fittings This invention relates to lighting fittings.

According to this invention a shroud for a lighting fitting comprises an outer member for enclosing the fitting, and an inner member for supporting the shroud on the fitting.

The outer member may be an open-ended cylinder; the cylinder may be outwardly flared at one end.

The inner member may define an aperture for receiving a terminal mounting of the lighting fitting.

The aperture may have an internal screwthread for engaging an external screw-thread on the terminal mounting.

The terminal mounting may have an internal screw-thread for engagement with a screwconnection at one end of a fluorescent lamp.

Alternatively the terminal mounting has internal formations for example slots cooperable with projections on a lamp to form a bayonet connection.

The inner member may be axially adjustable in relation to the outer member.

The lighting fitting may be a batten lampholder.

The invention also includes in combination a shroud as defined above and a lighting fitting. The invention also includes such a combination with a lamp in the fitting, the shroud covering also one end portion of the lamp.

The invention may be performed in various ways and one specific embodiment with possible modifications will now be described by way of example with reference to the accompanying diagrammatic drawings, in which: Fig. 1 is a part-section in a central vertical plane of one embodiment; Fig. 2 is a plan view on a larger scale of a modified light fitting shroud; and Fig. 3 is a part view similar to Fig. 1 of another arrangement.

Referring to Fig. 1, a ceiling 10 or other support has secured to it by countersunk screws 11 a batten lampholder having a circular plastics base 12 providing a mounting for electrical terminals shown schematically at 1 3.

The side of base 12 is provided with a screwthread which is in threaded engagement with screw-thread on a hollow conical support element 14 having an aperture which slidably receives a terminal holder 1 5 having hollow cylindrical part 1 6 the lower part of which is screw-threaded both internally and externally to form an Edison screw fitting. The internal thread can receive the externally threaded end 1 7 of a fluorescent electric lamp 18, for example an 18 watt 220v 50 Hz bulb reference SL-18 of Philips Electronic and Associated Industries Limited of London. This lamp has an internai fluorescent bulb 19 in a housing comprising an opaque conical end part 20 and a translucent or transparent generally cylindrical part 21 which may be externally fluted, as shown at 22.

An opaque lighting fitting shroud 7 is openended and has a generally cylindrical part 23 and includes an internal cross-member 24 defining an aperture having an internal thread received on the external thread 9. An internally threaded annular spacer 25 is interposed between the crossmember 24 and the support element 14.

A further conical member 26 is internally screw-threaded at one end and serves to hold the cross-member against the spacer ring 25.

The shroud 7 at its lower end 27 is substantially flush with the junction between parts 20, 21 and at its upper end is, optionally, flared outwardly at 28 and engages the ceiling 1 0. The outer diameter of the cylindrical part 23 is substantially the same as that of the part 21.

The mounting 15, which may be largely of plastics, includes electrical terminals shown schematically at 29 and the electric supply is through cables 30, 31.

The end 1 7 includes conical tip portion 32 and makes contact with the terminals in the mounting 1 5 in the usual way.

The shroud 7 can be associated with different sizes of batten lampholder by omitting the spacer 25 or having more than one spacer. The conical part 26 can be replaced by a ring similar to spacer ring 25.

The aperture 8 in the cross member need not be internally threaded but could be plain as shown in Fig. 2.

The cross-member 24 can take several forms; for example it may have four arms as shown at 24, 24a in Fig. 2.

In a further modification the cross-member 24 is axially adjustable in relation to the cylindrical part 23. For example the cross-member could be in threaded engagement with screw threads on the inner surface of the part 23. Alternatively the cross-member could be in sliding engagement with a friction fit in axial grooves in the part 23.

It will be appreciated that the batten lampholder can be used with a conventional tungsten filament bayonet-connection-light bulb by removing the terminal mounting 1 5 and replacing it with a bayonet type terminal mounting.

This is illustrated in Fig. 3 in which the lamp 1 8a has a neck 30 provided with opposed projections 31 detachably cooperable in slot formations in the holder part 16, conical part 26 being replaced by ring 26a.

It will also be appreciated that the shroud 7 may be sized to be usable with a plurality of conventional bayonet-type batten holders, possibly with the use of spacers 25, with the bayonet-type terminal mounting being replaced by a screw-thread terminal mounting such as mounting 1 5.

The shroud 7, as the batten holder, is made of electrically insulating material, for example a suitable plastics.

Claims

1. A shroud for a lighting fitting comprising an outer member for enclosing the fitting, and an inner member for supporting the shroud on the fitting.

2. A shroud as claimed in claim 1, in which the outer member is open-ended.

3. A shroud as claimed in claim 2, in which the outer member is cylindrical.

4. A shroud as claimed in claim 3, in which the outer member is outwardly flared at one end.

5. A shroud as claimed in any preceding claim, in which the inner member defines an aperture for receiving a terminal mounting of the lighting fitting.

6. A shroud as claimed in claim 5, in which the aperture is internally screw-threaded for engaging an external screw-thread on the terminal mounting.

7. A shroud as claimed in any preceding claim, in which the inner member is longitudinally adjustable in relation to the outer member.

8. A shroud for a lighting fitting substantially as hereinbefore described with reference to and as shown in Fig. 1, or Fig. 2, or Fig. 3, of the accompanying drawings.

9. In combination -- a shroud as claimed in any preceding claim and a lighting fitting.

10. A combination as claimed in claim 9, in which a terminal mounting of the lighting fitting has an internal screw-thread for engagement with a screw-connection at one end of a fluorescent lamp.

11. A combination as claimed in claim 9, in which a terminal mounting of the lighting fitting has internal formations co-operable with projections on a lamp to form a bayonet connection.

12. A combination as claimed in any of claims 9-11, in which the lighting fitting comprises a batten lampholder.

13. A combination of a shroud and a lighting fitting substantially as hereinbefore described with reference to and as shown in Fig. 1 of the accompanying drawings.

14. A combination as claimed in any of claims 9-1 3, including a lamp in the lighting fitting, the shroud covering one end portion of the lamp.