WO1999039131A1

WO1999039131A1 - Luminaires

Info

Publication number: WO1999039131A1
Application number: PCT/GB1999/000266
Authority: WO
Inventors: Michael Rollin Burn
Original assignee: Light Years Ahead Ipr Limited
Priority date: 1998-01-31
Filing date: 1999-01-26
Publication date: 1999-08-05
Also published as: AU2288999A; GB9802013D0

Abstract

There is disclosed a luminaire comprising a hollow extrusion (11) having as one wall a parabolic reflecting wall (12) and a second wall (13) extending arcuately behind the parabolic wall (12) from one edge thereof (12a) to the other (12b) and having a flexible reflective insert (14) on the parabolic wall sprung between edgewise lips (12c) thereof and having outside the lips recesses (15) for mounting a diffuser panel (16), the extrusion (11) having end caps (17) including journals (18) on endwise mounting brackets (19) including sockets (21) for a tubular lamp.

Description

LUMINAIRES

This invention relates to luminaires.

Luminaires are made in a wide variety of styles suitable for different types and wattages of lamp and adapted for different kinds of mounting in different locations. Generally speaking, fluorescent lighting, for indoors, is that the most efficient, running effectively cold and generating little heat - which is usually wasted energy - as compared to incandescent lamps.

However, conventional arrangements for fluorescent luminaires are themselves wasteful of energy because much of the light emitted by the fluorescent tube is absorbed by the material of the luminaire instead of providing the desired illumination. The energy saving in offices, shops, factories and other large spaces could be substantial if all the light output were used efficiently.

Many luminaires are, moreover, complex in construction and tube replacement is problematical, especially when the fixture is located in the ceiling or high up on a wall.

Most luminaires are single purpose - downlighters, uplighters, for example - so that one establishment with different lighting requirements for different areas may have a range of different luminaires.

The present invention provides a luminaire that is highly efficient in terms of useful light output, is simple in construction - and facilitates easy tube change - and is also versatile so that one design can serve many different lighting requirements. The invention comprises a luminaire comprising a hollow extrusion having as one wall a parabolic reflecting wall and a second wall extending arcuately behind the parabolic wall from one edge thereof to the other and having a flexible reflective insert on the parabolic wall sprung between edgewise lips thereof and having outside the lips recesses for mounting a diffuser panel or a lensed refractor system, the extrusion having end caps including journals on endwise mounting brackets including sockets for a tubular lamp.

The extrusion may have internal rigidifying webs between the parabolic wall and the second wall, and may house electrical equipment powering the lamp. The extrusion may be electrically shielding and may be of extrudable metal such as aluminium, which will effectively attenuate RF transmissions from electronic controllers for fluorescent tubes. The use of electronic drivers is itself energy-efficient and can be arranged to give instant power-up instead of the customary delay associated with conventional ballast and starter arrangements.

The parabolic wall may be a single parabola, the luminaire throwing a narrow angle beam, or two side-by-side parabolas, throwing a wide beam. Such narrow beam/wide beam extrusions and different extrusion lengths are all that is required to provide a range of highly-efficient 'universal' luminaires - all essentially to the same design and therefore able to constitute a comprehensive uniform lighting arrangement satisfying all the different requirements of a complex space.

The journal arrangement enables the luminaire to be used as an uplighter or a downlighter, or a wall wash unit and even standard, table and desk lamps. Embodiments of luminaires according to the invention will now be described with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of a ceiling mounted luminaire;

Figure 2 is a cross-section of a first aluminium extrusion for the luminaire of Figure 1;

Figure 3 is a cross-section of a second aluminium extrusion; and

Figure 4 is a view of a bracket showing how the extrusion and other components mounted therein.

The drawings illustrate luminaires comprising a hollow extrusion 11 having as one wall a parabolic reflecting wall 12 and a second wall 13 extending arcuately behind the parabolic wall 12 from one edge 12a thereof to the other 12b and having a flexible reflective insert 14 on the parabolic wall 12 sprung between edgewise lips 12c thereof and having outside the lips recesses 15 for mounting a lensed refractor system 16, the extrusion 11 having end caps 17 including journals 18 on endwise mounting brackets 19 including sockets 21 for a tubular lamp, not shown.

The refractor system 16 is preferably of clear, fluted plastic, and may itself be extruded. Clear plastic absorbs less light further improving the overall efficiency of the luminaire over conventional diffusers, which could, however, be used if full optical efficiency is not required.

The extrusion 11 has rigidifying webs 22 between the parabolic wall 12 and the second wall 13. - 4 -

The extrusion 11 houses electrical equipment such as electronic fluorescent tube drivers which generate RF radiation which can interfere with communications and computing equipment - the aluminium extrusion serves effectively to attenuate such RF radiation to an acceptably low level.

The parabolic wall of Figure 2 is a single parabola, in cross-section, which - with the tubular lamps in the focal position indicated in broken line at 23 - throws a narrow angle beam.

The parabolic wall of Figure 3 is formed of two side-by-side parabolas, the luminaire throwing a wide-angle beam. The centre lines of the two parabolas are divergent.

Figures 4 shows to greater detail one of the brackets 19, which have inlet grommets 25 for the electric cable. The journals 18 are made relatively stiff so that the luminaire can be adjusted and left in any desired angular position on the brackets, and include sealing arrangements against ingress of moisture.

For short luminaires such for example as desk, table and wall lighting, there may be provided only one mounting bracket holding the luminaire cantilever fashion. A modified end cap, or one with a plug in place of the journal, could be used at the free end.

Claims

1. A luminaire comprising a hollow extrusion having as one wall a parabolic reflecting wall and a second wall extending arcuately behind the parabolic wall from one edge thereof to the other and having a flexible reflective insert on the parabolic wall sprung between edgewise lips thereof and having outside the lips recesses for mounting a diffuser panel, the extrusion having end caps including journals on endwise mounting brackets including sockets for a tubular lamp.

2. A luminaire according to claim 1, in which the extrusion has internal rigidifying webs between the parabolic wall and the second wall.

3. A luminaire according to claim 1 or claim 2, the extrusion housing electrical equipment powering the lamp.

4. A luminaire according to any one of claims 1 to 3, the extrusion being electrically shielding.

5. A luminaire according to any one of claims 1 to 4, being of extrudable metal such as aluminium.

6. A luminaire according to any one of claims 1 to 5, of which the parabolic wall is a single parabola, the luminaire throwing a narrow angle beam.

7. A luminaire according to any one of claims 1 to 5, of which the parabolic wall is formed of two side-by-side parabolas, the luminaire throwing a wide angle beam. - 6 -

8. A luminaire according to any one of claims 1 to 7, of which the end caps comprise assemblies of moulded components.

9. A luminaire according to any one of claims 1 to 8, in which the end caps seal against ingress of moisture.