LIGHTING DEVICE

Abstract

The invention relates to a lighting device kit of parts comprising a lamp (3) and a lamp shade (5). The lamp (3) of the lighting device comprises a light source (11) and a heat sink area (13) comprising a main heat dissipating surface (15). The lamp shade (5) of the lighting device comprises a shade structure (17) conjoined via a thermal path part with a cooling structure (21) comprising a main surface (24). In a mounted position of the lamp shade (5) and the lamp (3), the main surface (24) of the cooling structure (21) adjoins the main heat dissipating surface (15) of the heat sink area (13). The invention further relates to a lamp and a lamp shade of said lighting device kit of parts.

Claims

1. A lighting device kit of parts forming a lighting device comprising: a lamp comprising a light source and a heat sink area comprising a main heat dissipating surface; a lamp shade comprising a shade structure conjoined via a thermal path with a cooling structure comprising a main surface; in a mounted position of the lamp shade and the lamp, the main surface of the cooling structure adjoins the main heat dissipating surface of the heat sink area, and the light source is arranged around the heat dissipating surface, wherein the cooling structure comprises two fins with mutually opposed main surfaces, said fins having a respective contour of a respective main surface alike a contour of a respective main heat dissipating surface and adjoin the respective main heat dissipating surface on either side of the heat sink area.

2. A lighting device kit of parts as claimed in claim 1, characterized in that the thermal path has a cross-sectional width Wp which is at least 25% of the largest cross-sectional width Ws of the main surface of the cooling structure.

3. A lighting device kit of parts as claimed in claim 1, characterized in that the cooling structure is in one piece with the lamp shade.

4. (canceled)

5. (canceled)

6. A lighting device kit of parts as claimed in claim 1, characterized in that the cooling structure abuts with its main surface with resilient/press force against the main heat dissipating surface of the heat sink area.

7. A lighting device kit of parts as claimed in claim 1, characterized in that the heat sink area is clamped by the two fins.

8. A lighting device kit of parts as claimed in claim 1, characterized in that the cooling structure and the heat sink area have a similar shape.

9. A lighting device kit of parts as claimed in claim 1, characterized in that the cooling structure is surrounded by the lamp shade structure.

10. A lighting device kit of parts as claimed in claim 1, characterized in that the light source is concentrically arranged around the heat sink area.

11. A lighting device kit of parts as claimed in claim 1, characterized in that the lamp shade is made in two similar halves.

12. A lighting device kit of parts as claimed in claim 1, characterized in that the lamp and lamp shade are mutually shiftable along a lamp axis.

13. A lighting device kit of parts as claimed in claim 1, characterized in that the surface of lamp shade facing the light source has a reflectivity of at least 80%, preferably at least 90%.

14. (canceled)

15. A lamp shade having all the characteristics of the lamp shade of the lighting device kit of parts as claimed in claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The invention will now be further elucidated by means of the schematic drawings in which:

[0017] FIG. 1 shows an exploded view of a first embodiment of the lighting device kit of parts according to the invention;

[0018] FIG. 2 shows a cross section of the assembled lamp of FIG. 1;

[0019] FIG. 3A-B shows a cross section of a lamp shade respectively a side view of a lamp of the lighting device kit of parts according to the invention;

[0020] FIG. 4 shows a cross sectional view of lamp shade of a second embodiment of the lighting device kit of parts according to the invention;

[0021] FIG. 5 shows a cross sectional view of lamp shade of a third embodiment of the lighting device kit of parts according to the invention;

[0022] FIG. 6 shows a cross sectional view of a fourth embodiment of an assembled lamp.

[0023] As illustrated in the figures, the sizes of parts may be exaggerated for illustrative purposes and, thus, are provided to illustrate the general structures of embodiments of the present invention. Like reference numerals refer to like elements throughout.

DETAILED DESCRIPTION

[0024] FIG. 1 shows an exploded view of a first embodiment of the lighting device kit of parts 1 of the invention. The kit of parts comprises a lamp 3 and a lamp shade 5, which are housed inside a housing 7 by means of a fastening element 9, for example an optical plate or fastening ring 9. The lamp comprises a light source 11 and a heat sink area 13 comprising a main heat dissipating surface 15. The light source is a plurality of LEDs, in the figure arranged in a ring and enveloped by a circular, hollow tube 25 at the periphery 16 of main heat dissipating surface. The lamp shade, which is made into two similar halves 6a, 6b, comprises a shade structure 17 conjoined via a thermal path 19 with a cooling structure 21 comprising a main surface 23. The cooling structure is embodied as a fin which has a contour alike the contour of the main heat dissipating surface of the lamp. The lamp has an E27 socket 27, but the socket could have any suitable shape for mounting and electrical contacting with a respective fitting, for example a bayonet socket or a G53 socket.

[0025] FIG. 2 shows a cross section of the assembled lighting device kit of parts 1 of FIG. 1 in a direction transverse to the main heat dissipating surface 15 of the lamp 3, in which a lamp shade axis 39 of the lamp shade 5 coincides with a lamp axis 45 of the lamp. As shown, in a mounted position of the lamp shade 5 and the lamp, the main surface 23 of the cooling structure 21 adjoins the main heat dissipating surfaces 15 of the heat sink area 13. The cooling structure, i.e. two fins, rests on both sides with its main surfaces with resilient force against said heat dissipating surfaces and hence the lamp shade is mounted with clamping force onto the lamp. The cross section clearly shows the hollow tube structure 25 which surrounds the light source 11, i.e. LEDs 26 in the figure, and which forms an integral part with a socket 27 of the lamp. The socket of the lamp comprises an E27 Edison base 29 by which it can be fitted into an E27 lamp fitting, and it comprises a socket housing 31 in which lamp electronics 33 for driving the LEDs is housed. Because the socket housing, and hence the lamp electronics, is arranged outside the lamp shade, the lamp electronics are even better shielded from the heat generated by the LEDs light source during operation.

[0026] The lamp is surrounded by the housing 7 having an insertion opening 51 and a height H, the lamp is attached to said housing via the lamp socket and via a rim 35 of the lamp shade. Said rim of the lamp shade forms a border of a light emission window 37 of the lamp via which light from the lighting device kit of parts 1 is (to be) issued to the exterior. Said light emission window is closed by a light transmitting plate 9, which light transmitting plate optionally can be provided with an optical structure on its main face facing the light source, for example meso-optical structure, to redistribute the light before being issued by the lighting device kit of parts. The lighting device kit of parts as shown in FIG. 2 is particularly suitable as a recessed lighting device for being built in into (false) ceilings.

[0027] FIG. 3A-B shows a cross section of a lamp shade 5 respectively a side view of a lamp 3 of the lighting device kit of parts according to the invention. The lamp shade in FIG. 3A comprises a circumferential lamp shade structure 17 around a virtual lighting lamp shade axis 39, and comprises a cooling structure 21 of two similar halves 22a, 22b, i.e. with two main surfaces 24a, 24b which extend mutually parallel along the lamp shade axis. Each main surface is connected to the lamps shade via a respective thermal path part 20a, 20b. The lamp shade structure, the thermal path parts and the cooling structure are made in one, integral piece from thermal conductive material, in the figure made of aluminum metal. The thermal path has a cross-sectional width Wp transverse to the lamp shade axis which is about 40% of the largest cross-sectional width Ws transverse to the lamp shade axis of the main surface (only a half width of Wp and Ws is shown). The relatively large width of the thermal path enables a good heat transfer from the cooling structure to the shade structure, hence enabling the shade structure to function simultaneously as a lamp shade and cooling part. The lamp shade has a circumferential rim 35 which forms a border of a light emission window 37 of the lamp shade, and via which the lamp shade is attached to a housing 7 by means of an fastening element 9, in the figure an optical plate, or alternatively a fastening ring, which fastening element extends essentially transverse to the lamp shade axis.

[0028] The lamp 3 has hollow tube structure 25 at the periphery 16 of the main heat dissipating surface 15, said tube structure surrounds the LEDs and forms an integral part with a socket 27 of the lamp, i.e. the light source is arranged around the heat dissipating surface of the heat sink area. As is shown in the figure, the light source and the heat sink area are concentrically arranged with the light source arranged around the heat dissipating surface, preferably the periphery of the heat dissipating surface is at least over 75% surrounded by the light source, in the figure for about 90%. The socket of the lamp comprises an E27 Edison base 29 with a first, extreme central electrical contact 41, and a second, circumferential electrical contact 43 with a spiral-shaped outer surface for electrically contacting an E27 fitting when mounted there into. The lamp has a virtual lamp axis 45 which extends through the first extreme, central electrical contact of the socket, with the second electrical contact around said lamp axis. Said lamp axis further extending essentially parallel to main heat dissipating surface of the heat sink area 13 and through a tip portion 47 of the light source 11 most remote from the lamp socket. In assembled position of the lamp and the lamp shade both the virtual axis of the lamp shade and the virtual axis of the lamp extend essentially parallel or even coincide.

[0029] FIG. 4 shows a cross sectional view of lamp shade 5 of a second embodiment of the lighting device kit of parts according to the invention. The cooling structure 21 of the lamp shade comprises a polygonal, in the figure an octagonal, main surface 23, which is adapted to snugly match with the main heat dissipating surface of the heat sink area of the lamp which thereto has an LEDs in an octagonal arrangement as the light source (not shown). Many other arrangements of the LEDs are envisaged, for example in a rectangular, hexagonal or two parallel line arrangement (either along or transverse to the axis of the lamp). The cooling structure of the lamp shade is connected to the lamp shade structure 17 via a thermal path 19 having a cross sectional width Wp which is about 25% of the largest cross-sectional width Ws of the main surface 23. The lamp shade structure and thermal path are made into one integral piece of aluminum metal to which the cooling structure, made of copper metal is, releasably fixed, for example via screws, thus enabling an exchange of the cooling structure, for example to adapt the cooling structure to an alternative lamp design.

[0030] FIG. 5 shows a cross sectional view of lamp shade 5 of a third embodiment of the lighting device kit of parts according to the invention in which the cooling structure 21 of the embodiment of FIG. 4 has been exchanged by an alternative cooling structure. The cooling structure of the lamp shade of the embodiment of FIG. 5 comprises a round, circular main surface 23, which is adapted to snugly match with the main heat dissipating surface of the lamp which thereto has an LEDs in a circular arrangement as the light source (not shown). In addition the cooling structure comprises an open slot 49 to enable accommodation of an additional central line arrangement of LEDs provided in the lamp along the lamp shade axis 39 (or lamp axis). Such an additional line of LEDs can be used for various purposes, for example to boost up the light output of the lamp or to be used as emergency lighting or for additional of extra color features or figurative features when directly viewed. The cooling structure of the lamp shade is connected to the lamp shade structure 17 via a thermal path 19 having a cross sectional width Wp which is about 30% of the largest cross-sectional width Ws of the main surface 23.

[0031] FIG. 6 shows a cross section of a fourth embodiment of an assembled lighting device kit of parts 1 of a lamp 3 and a lamp shade 5 in a direction transverse to the main heat dissipating surface 15 of the lamp 3, in which a lamp shade axis 39 of the lamp shade coincides with a lamp axis 45 of the lamp. The lamp shade and the lamp are mutually mounted by the lamp shade being slidebly clamped with its cooling structure onto the heat dissipating surface of the heat sink. The figure shows schematically the lamp shade in a first position and in a second position shifted along the axes over a distance ΔL with respect to the lamp. The two halves 22a,22b of the cooling structure 21 then not fully covering the main heat dissipating surface but being somewhat smaller thus enabling said shift of ΔL of the cooling structure over the main heat dissipating surface of the heat sink area 13 via a sliding connection. Thus adaptation of the height H.sub.LD by a distance ΔL of the lighting device along the lamp axis/lamp shade axis to the height H of the housing (not shown) is enabled.