GB2400885A

GB2400885A - Lighting apparatus

Info

Publication number: GB2400885A
Application number: GB0309071A
Authority: GB
Inventors: Terry Michael Payne
Original assignee: Monodraught Ltd
Current assignee: Monodraught Ltd
Priority date: 2003-04-22
Filing date: 2003-04-22
Publication date: 2004-10-27
Anticipated expiration: 2023-04-22
Also published as: GB2400885B; GB0309071D0

Abstract

A lighting apparatus 10 conveys daylight from a rectangular skylight 18 in a roof 12 of a building to a circular opening in ceiling 15 of a room 14 in the building. The apparatus 10 includes an elongate hollow internally reflective tubular part 30 of circular cross section having first and second open ends and a hollow internally reflective adaptor part 40 having a first open end 42 for connection to or merging into the first open end of the tubular part 30 and a second open end 45 which is rectangular for location adjacent a frame of the skylight 18. The second open end of the tubular part 30 may connect to a diffuser 38 located in the ceiling 15 of the room 14.

Description

1 2400885

LIGHTING APPARATUS

The present invention relates to lighting arrangements for use with skylights.

Skylights are commonly used in existing or new buildings where more light is required than is received through windows or glazed doors. A skylight generally includes a rectangular frame, usually made of either wood or metal, mounted within the roof structure of a building in order to lie generally flush with the roof structure. A clear sheet material, typically glass, is used to cover the opening in the roof, the clear sheet material being mounted within the frame.

According to the invention, there is provided a lighting apparatus for conveying daylight from a rectangular skylight in a roof of a building to a room in the building, the lighting apparatus being for location in a cavity between the roof and a ceiling of the room and including: an elongate hollow, internally reflective tubular part of circular cross section having a mirror-finish interior; and a hollow, internally reflective adaptor part having a mirror-finish interior and including a first open end which is substantially circular or oval, for connecting to or merging into the tubular part, and a second open end which is substantially rectangular, for location adjacent to a frame of the skylight.

Preferably substantially an entire inner surface of the tubular part and the adaptor part have a mirror-finish, such that at least 90% of available light is reflected. Most preferably about 96% of the available light is reflected.

Where the term "skylight" is used it is intended to cover any window or other opening in a roof through which light may enter the building.

It is possible that the lighting arrangement could be used to convey light to a wall of a room, for example a sloping wall, and the term "ceiling" is intended to cover this situation.

The adaptor part may include a flange at its first end, the flange being adapted to connect to an end of the tubular part. The flange may be substantially cylindrical or substantially frustoconical.

Alternatively the adaptor part and the tubular part may be formed as a unitary component.

The adaptor part preferably includes a rectangular flange at its second end, the flange being adapted to extend substantially to a sheet of transparent material of the skylight. The flange is preferably adapted for connection to the frame of the skylight and is preferably shaped and sized to fit inside and adjacent to the frame of the skylight, abutting the sheet of transparent material.

Preferably the flange includes an outer edge which abuts the sheet of transparent material in use. Preferably the flange is internally reflective substantially to its outer edge.

The adaptor part preferably includes a continuous wall extending between its two ends, the cross sectional shape of the wall gradually changing from substantially circular or oval at its first end to substantially rectangular at its second end. The wall may flare outwardly from its first to its second end, the angle of the flare being between 20 and 50 .

Preferably an entire internal surface of the adaptor part is internally reflective.

The tubular part may be substantially cylindrical or may be frustoconical or include a frustoconical section. The tubular part may be substantially straight or may include bends. Preferably the entire internal surface of the tubular part is internally reflective.

The tubular part preferably includes a first circular open end which is adapted to connect to or merge into the first end of the adaptor part. The tubular part preferably includes a second circular open end which is adapted to connect to a diffuser located within the ceiling of the room.

According to the invention there is further provided a lighting apparatus according to any of the preceding paragraphs, the lighting apparatus further including a skylight comprising a substantially rectangular frame and at least one sheet of substantially transparent or translucent material located within the frame. The skylight is preferably adapted for location in a roof of a building, preferably substantially flush with the roof. The frame may be l O square. The skylight may include a central glazing bar.

According to the invention there is further provided a lighting apparatus according to any of the preceding paragraphs, the lighting apparatus further including a diffuser for diffusing light into the room. The diffuser is preferably adapted to attach to the ceiling, adjacent to an end of the tubular part. The diffuser may be generally dome shaped, a centre of the dome extending into the room in use.

An embodiment of the invention will be described for the purpose of illustration only with reference to the accompanying drawings in which: Fig. 1 is a perspective view illustrating a lighting apparatus according to the invention; Fig. 2 is a sectional view illustrating a lighting apparatus according to the invention; and Figs. 3A to 3C are plan and side views respectively of a part of a lighting apparatus according to the invention.

Referring initially to Figs. 1 and 2, a lighting apparatus 10 is illustrated, for conveying daylight from a sloping roof 12 of a buliding to a room 14 below.

A roof cavity 16 is located between the roof 12 and a ceiling 15 of the room 14.

A rectangular skylight 18 is located within the sloping roof 12. The skylight 18 includes an inner frame 20 which locates within the roof structure and an outer malleable weatherproof flashing 22 installed in accordance with normal building practice. The skylight 18 includes two sheets of transparent material in the form of inner and outer panes of glass 26, 28 thereby forming a double glazed skylight. The skylight 18 may further include a central glazing bar 29 for aesthetic reasons. As an alternative, the skylight could be square, with no central bar.

JO The lighting apparatus 10 is located within the roof cavity 16, and includes an internally reflective tubular part in the form of a light pipe 30. The light pipe 30 is generally cylindrical and may have a diameter of around 0.2m, but could be up to 1.5m in diameter.. The light pipe 30 includes a straight section 32 and an angled section 34 in which it changes direction by about l 5 30 or as may be necessary to suit the roof slope, and is manufactured, over its entire inner surface, in a highly reflective and mirror-finish material.

The light pipe 30 includes a first end 36 which terminates approximately flush with the ceiling 15 of the room 14. A generally circular and shallowly domed diffuser member 38 may be incorporated and lies generally flush with the ceiling 15 and acts to diffuse light carried by the light pipe into the room 14.

An opposite end 39 of the light pipe 30, remote from the ceiling 15, is connected to an adaptor part 40 of the lighting apparatus 10. The light pipe may be formed integrally with the adaptor part 40 or formed separately and connected thereto.

The adaptor part 40 is manufactured from a highly reflective material over its entire Inner surface, being a mirror-finish material, which forms part of a path for light to travel from the skylight 18 to the diffuser member 38 and therefore into the room 14. The adaptor part 40 serves to capture and reflect light entering the skylight and to channel the light down the light pipe 30.

Referring also to Figs. 3A to 3C the adaptor part 40 includes a first open end 42 which is substantially circular when viewed end on. It is this end which merges into or is connected to the light pipe 30. In the illustrated embodiment, a cylindrical flange 43 about 50 mm deep is located at the open end 42.

An opposite open end 45 of the adaptor part 40 is rectangular when viewed end-on, and is provided with a flange 44, again about 50 mm deep.

The flange 44 is rectangular shaped, including straight sides 47 at right angles to one another, such that it may fit just inside and adjacent to the inner frame of the skylight. The flange 44 also consists of the highly reflective, mirror- finish material, all over its internal surface 46 such that in use the reflective material extends right up to the inner pane of glass 26.

The open end 45 may have dimensions of between 0.3 and 0.6 m by between 0. 3 and 0.6 m, depending upon the size and shape of the skylight.

Between the generally cylindrical flange 43 which connects the adaptor part 40 to the light pipe 30 and the generally rectangular flange 44 which connects the adaptor part 40 to the inner frame 20 of the skylight 18, is a mid part 48 of the adaptor part. The shape of this mid part 48 is illustrated most clearly in Figs. 3A to 3C. It is this mid part which gradually changes from a circular cross section to a rectangular cross section.

The mid part 48 comprises a shaped wall which includes planar triangular parts 50, the bases of the triangles corresponding to the respective sides 47 of the rectangular flange 44. Between the planar triangles 50 are profiled corner pieces 52 which are shaped such that they allow one planar triangle 50 to merge smoothly into the adjacent planar triangle which lies at right angles to it. The profiled corner pieces themselves merge smoothly into the cylindrical flange 43.

The mid part 48 may flare outwardly at an angle of around 40 to 50 .

There is thus provided a lighting arrangement which conveys light from the roof of a building to a room extremely effectively. The apparatus captures the same amount of daylight as a conventional skylight but intensifies and reflects the captured daylight down into the light pipe and therefore to the room. This provides significantly more light to the room than is provided by a conventional tubular light pipe or by a skylight. Tubular light pipes are limited by the size of the dome on the roof surface and conventional roof lights and skylights include a frame or lining below the glass surface (to the inside of the glass), this frame or lining usually being made of wood or aluminium. The inventors have appreciated that this lining absorbs some of the light captured by the skylight and can result in 20% less light being reflected into the room or space below than would be the case without the frame. In the above described preferred embodiment of the present invention, the mirror finish lining is taken right to the underside of the glass and this element of loss of light is therefore eliminated. The lighting arrangement is also suitable for use with listed buildings and in conservation areas, as it can lie flush with a roof rather than being provided with a bulbous dome.

Various modifications may be made to the above described embodiment without departing from the scope of the invention. In particular, the shapes of the components may be modified. For example a square skylight could be used, resulting in a square flange 45 being required. In addition, a thermal liner may be provided for the roof light to minimise the possibility of condensation forming internally.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

1. A lighting apparatus for conveying daylight from a rectangular skylight In a roof of a building to a room in the building, the lighting apparatus being for location in a cavity between the roof and a ceiling of the room and including: an elongate hollow, internally reflective tubular part of circular cross section having a mirror-finish interior; and a hollow, internally reflective adaptor part having a mirror-finish interior and including a first open end which is substantially circular or oval, for connecting to or merging into the tubular part, and a second open end which is substantially rectangular, for location adjacent to a frame of the skylight.

2 A lighting apparatus according to claim 1, wherein substantially an entire inner surface of the tubular part and the adaptor part have a mirror finish, such that at least 90% of available light is reflected.

3. A lighting apparatus according to claim 2, wherein about 96% of the available light is reflected.

4. A lighting apparatus according to any preceding claim, wherein the adaptor part includes a flange at its first end, the flange being adapted to connect to an end of the tubular part.

5. A lighting apparatus according to any of claims 1 to 3, wherein the adaptor part and the tubular part are formed as a unitary component.

6 A lighting apparatus according to any preceding claim, wherein the adaptor part includes a rectangular flange at its second end, the flange being adapted to extend substantially to a sheet of transparent material of the skylight.

7. A lighting apparatus according to claim 6, wherein the flange is adapted for connection to the frame of the skylight and is shaped and sized to fit inside and adjacent to the frame of the skylight, abutting the sheet of transparent material.

8. A lighting apparatus according to claim 6 or claim 7, wherein the flange includes an outer edge which abuts the sheet of transparent material in use.

9. A lighting apparatus according to any of claims 6 to 8, wherein the flange is internally reflective substantially to its outer edge.

10. A lighting apparatus according to any preceding claim, wherein the adaptor part includes a continuous wall extending between its two ends, the cross sectional shape of the wall gradually changing from substantially circular or oval at its first end to substantially rectangular at its second end.

11. A lighting apparatus according to claim 10, wherein the wall flares outwardly from its first to its second end, the angle of the flare being between 20 and 50 .

12. A lighting apparatus according to any preceding claim, wherein an entire internal surface of the adaptor part is internally reflective.

13. A lighting apparatus according to any preceding claim, wherein the entire internal surface of the tubular part is internally reflective.

14. A lighting apparatus according to any preceding claim, wherein the tubular part includes a first circular open end which is adapted to connect to or merge into the first end of the adaptor part and a second circular open end which Is adapted to connect to a diffuser located within the ceiling of the room.

15. A lighting apparatus according to any preceding claim, wherein the lighting apparatus further including a skylight comprising a substantially rectangular frame and at least one sheet of substantially transparent or translucent material located within the frame

16. A lighting apparatus according to claim 15, wherein the skylight is adapted for location in a roof of a building, substantially flush with the roof.

The frame may be square The skylight may include a central glazing bar.

17. A lighting apparatus according to any preceding claim, wherein the lighting apparatus further including a diffuser for diffusing light into the room, the diffuser being adapted to attach to the ceiling, adjacent to an end of the tubular part.

l O

18. A lighting apparatus substantially as herein described with reference to the accompanying drawings.