Lighting device

Patent metadata

Field	Value
Publication number	US-2016154171-A1
Application number	US-201514943393-A
Country	US
Kind code	A1
Filing date	Nov 17, 2015
Priority date	Nov 28, 2014
Publication date	Jun 2, 2016
Grant date	—

Abstract

A lighting device according to one embodiment includes a light guide member, at least one light source and a substrate on which the light source is mounted. The light guide member includes a first surface facing an outside of the lighting device, a second surface opposite to the first surface, and a side surface extending from an end of the first surface to an end of the second surface. The light guide member also includes a diffusion portion. The light source faces a side surface of the light guide member. The casing includes a thermal dissipation portion formed of a metal and extending along the second surface of the light guide member. The casing supports the substrate and is thermally connected to the light source.

First claim

What is claimed is:

1 . A lighting device comprising:
a light guide member including a first surface facing an outside of the lighting device, a second surface opposite to the first surface, and at least one side surface extending from an end of the first surface to an end of the second surface, the light guide member also including a diffusion portion; at least one light source facing the at least one side surface of the light guide member; a substrate on which the light source is mounted; and a casing including a thermal dissipation portion which is formed of a metal and extends along the second surface of the light guide member, the casing supporting the substrate and being thermally connected to the light source.

2 . The lighting device of claim 1 , wherein
the light guide member is formed to be polygonal; and the at least one light source includes a plurality of light sources, and the at least one side surface of the light guide member includes a plurality of side surfaces, the plurality of light sources being arranged along the plurality of side surfaces.

3 . The lighting device of claim 2 , wherein the diffusion portion is formed to be circular on a central portion of the polygonal light guide member.

4 . The lighting device of claim 1 , wherein the thermal dissipation portion includes an inclined portion extending along the second surface of the light guide member and gradually outward thickened toward a central portion of the light guide member.

5 . The lighting device of claim 4 , wherein the inclined portion includes a reflective surface permitted to reflect light received from the light source to the outside of the lighting device.

6 . The lighting device of claim 4 , wherein the light guide member includes a portion gradually thinned toward the central portion of the light guide member, the portion gradually thinned being formed by inclining the second surface toward the first surface along an outline of the inclined portion.

7 . The lighting device of claim 4 , wherein
the light guide member includes an opening formed therethrough from the second surface to the first surface; and the inclined portion is inserted in the opening of the light guide member, and exposed to the outside of the lighting device through the opening.

8 . The lighting device of claim 7 , wherein the diffusion portion is provided on an inner peripheral surface of the opening of the light guide member, and the inner peripheral surface gradually inclines such that an inner diameter of the diffusion portion gradually increases from the second surface to the first surface.

9 . The lighting device of claim 1 , wherein
the light guide member includes an opening formed therethrough from the second surface to the first surface; and the casing includes a through hole formed therein and opening in the opening of the light guide member to cause an interior of the casing to communicate with the outside of the lighting device.

10 . The lighting device of claim 9 , wherein a side surface of the casing includes an air hole formed therein to discharge, to an outside of the casing, air flowing from the outside of the lighting device into the casing via the through hole.

11 . The lighting device of claim 9 , further comprising:
a power supply circuit housed in the casing; and a connector included in the power supply circuit and connected to a detachable wire, wherein the connector is permitted to be exposed to the outside of the lighting device via the through hole.

12 . The lighting device of claim 1 , wherein the light guide member is formed like a bowl and also faces the side surface of the casing.

13 . A lighting device comprising:
at least one light source; a substrate provided with the light source; a light-transmitting member including a first surface facing an outside of the lighting device, a second surface opposite to the first surface, and an opening formed therethrough from the second surface to the first surface, and configured to transmit light received from the at least one light source, the light-transmitting member being provided with a diffusion portion; and a casing supporting the substrate and including a through hole which communicates with the opening of the light-transmitting member and causes an interior of the casing to communicate with an outside of the lighting device.

14 . The lighting device of claim 13 , wherein an air hole enabling air flowing from the outside of the lighting device into the casing via the through hole to flow to the outside of the lighting device is formed in a side surface of the casing.

15 . The lighting device of claim 13 , further comprising:
a power supply circuit housed in the casing; and a connector included in the power supply circuit and connected to a detachable wire, wherein the connector is permitted to be exposed to the outside of the lighting device via the through hole.

16 . A lighting device comprising:
at least one light source; a substrate provided with the light source; a light-transmitting member including a first surface facing an outside of the lighting device, a second surface opposite to the first surface, and configured to transmit light received from the at least one light source, the light-transmitting member being provided with a diffusion portion; a casing supporting the substrate; and an inclined portion provided in the casing and permitted to reflect light received from the at least one light source to the outside of the lighting device, the inclined portion being gradually outward thickened toward a center of the casing along the second surface of the light-transmitting member.

17 . The lighting device of claim 16 , wherein
the light-transmitting member includes an opening formed therethrough from the second surface to the first surface; and the diffusion portion is provided on an inner peripheral surface of the opening of the light-transmitting member, the inner peripheral surface inclining such that an inner diameter of the inner peripheral surface gradually increases from the second surface to the first surface.

18 . The lighting device of claim 17 , wherein the inner peripheral surface inclines within a range of from not less than 70° to less than 90° with respect to the second surface.

Assignees

• Toshiba Kk

Inventors

• Kato Mitsuaki
• Hayashihara Hiromichi
• Ohno Hiroshi
• Takamatsu Tomonao

Classifications

• F21V5/00

  Refractors for light sources (characterised by cooling arrangements F21V29/504) · CPC title

• F21K9/61

  using light guides · CPC title

• F21V29/83

  the elements having apertures, ducts or channels, e.g. heat radiation holes · CPC title

• F21S8/026

  intended to be recessed in a ceiling or like overhead structure, e.g. suspended ceiling · CPC title

• G02B6/0051

  Diffusing sheet or layer · CPC title