Lamp having outer shell to radiate heat of light source

• US 9,772,098 B2
• Filed: 08/03/2012
• Issued: 09/26/2017
• Est. Priority Date: 04/08/2005
• Status: Expired due to Fees

• Current Assignee: Toshiba Lighting & Technology Corporation (Toshiba Corporation)
• Original Assignee: Toshiba Lighting & Technology Corporation (Toshiba Corporation)
• Inventors: Osawa, Shigeru, Morikawa, Kazuto
• Primary Examiner(s): Husar, Stephen F
• Application Number:
  US13/566,612
• Publication Number:
  US 20120300477A1
• Time in Patent Office: 1,880 Days
• Field of Search: 36231101, 362240, 36224901, 36224902, 362227, 362 88, 362218, 362363, 362264, 362265, 362373, 362543, 362544, 362294, 36224905, 362646, 313311, 31331811, 313 44- 46
• CPC Class Codes: F21K 9/23 Retrofit light sources for lighting devices with a single fitting for each light source, e.g. for substitution of incandescent lamps with bayonet or threaded fittings
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21K 9/238 Arrangement or mounting of circuit elements integrated in the light source
• CPC Class Codes: F21V 17/101 permanently, e.g. welding, gluing or riveting
• CPC Class Codes: F21V 23/002 Arrangements of cables or conductors inside a lighting device, e.g. means for guiding along parts of the housing or in a pivoting arm
• CPC Class Codes: F21V 23/006 the substrate being distinct from the light source holder
• CPC Class Codes: F21V 29/507 of means for protecting lighting devices from damage, e.g. housings
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/713 in direct thermal and mechanical contact of each other to form a single system
• CPC Class Codes: F21V 29/773 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 29/83 the elements having apertures, ducts or channels, e.g. heat radiation holes
• CPC Class Codes: F21V 29/89 Metals
• CPC Class Codes: F21V 3/00 Globes; Bowls; Cover glasses with refracting properties F21V5/00; with reflecting properties F21V7/00; characterised by cooling arrangements F21V29/506
• CPC Class Codes: F21V 9/08 for producing coloured light, e.g. monochromatic; for reducing intensity of light with provision for controlling the colour F21V9/40
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H05B 45/30 Driver circuits
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

According to one or more arrangements, a lighting device such as a lamp may include a cover a device body. The device body may have a projection having a support surface at one end and an attachment portion to which the cover is configured to attach. In one or more examples, while the cover is configured to attach to the attachment portion, the cover may be configured to cover the supporting surface of the projection. The cover portion may include a translucent cover portion in some configurations. Additionally or alternatively, the supporting surface of the projection portion may be disposed closer to a center of the cover portion than the attachment portion. In one example, the projection portion may be disposed closer to the cover portion center by a distance equal to a height of the projection portion.

Claims

1. A lighting device comprising:

a cover portion; and

a device body made of metal and having;

a peripheral wall comprising a heat radiating surface, the heat radiating surface being provided outside the device body;

an end wall integrally formed with the peripheral wall, the end wall comprising a light source support at an end, wherein the cover portion is configured to cover the light source support when the cover portion is assembled with the device body;

a light source provided on the light source support, the light source comprising a wiring board on which a light-emitting element is mounted, the wiring board being fixed to the light source support by a screw to be in tight contact with the light source support and thermally connected to the light source support;

an attachment portion to which the cover portion is configured to attach, the attachment portion including a recess configured to receive one end of the cover portion, the recess being provided in the end wall to circularly surround the light source support;

a receptacle defined by a space enclosed with the peripheral wall and the end wall, the receptacle located closer to a center of the device body than the recess;

a connecting member made of resin and connected to an end portion of the peripheral wall on an opening side of the receptacle; and

a lighting circuit disposed in a receptacle space defined by the receptacle and the connecting member,

wherein the peripheral wall between the receptacle and the heat radiating surface has a thickness which increases as a distance from an opening side of the receptacle to the end wall increases.

2. The lighting device of claim 1, wherein the cover portion includes a translucent cover portion.

3. The lighting device of claim 1, wherein the wiring board includes a substrate and a thermal diffusion layer stacked on the substrate, the thermal diffusion layer being interposed between the substrate and the light source support.

4. The lighting device of claim 1, wherein the screw is screwed into the light source support through a center of the wiring board.

5. The lighting device of claim 1, wherein the receptacle is positioned inside the heat radiating surface.

6. The lighting device of claim 1, wherein the device body comprises a heat conduction path extending from the light source support to the heat radiating surface.

7. The lighting device of claim 6, wherein the heat conduction path includes a portion passing between the recess and the receptacle.

8. The lighting device of claim 1, wherein the device body includes a projection projecting from the light source support to the cover portion, the projection comprising a flat supporting surface at an end, and the wiring board being fixed to the projection by the screw in tight contact with the flat supporting surface.

9. The lighting device of claim 1, wherein:

the heat radiating surface tapers from the end wall to the connecting member; and

the recess has a depth which is greater than a thickness of the end wall and provided with an adhesive to secure an end of the cover portion, and

wherein the receptacle is smaller in diameter than the recess.

10. The lighting device of claim 9, wherein the end wall is connected to an end of the peripheral wall via a narrow portion arranged at the end of the peripheral wall and between a bottom of the recess and the receptacle, wherein the end of the peripheral wall wider than the narrow portion.

11. The lighting device of claim 10, wherein the lighting circuit comprises a wiring board, which includes a first surface mounted with a circuit component and a second surface opposite to the first surface, the lighting circuit being disposed in the receptacle space such that the first surface and the second surface face an inner circumference of the peripheral wall, and a distance between the first surface and the inner circumference is greater than a distance between the second surface and the inner circumference.