Patent ID: 8388183
Filing Date: 2013-03-05
Classification: F21K,F21V,F21Y

Abstract:
1. A lamp comprising: a light source including a semiconductor light-emitting device; a base through which electric power is received; a lighting circuit including a circuit device which generates electric power for causing said light source to emit light, using the electric power received through said base; an inner casing which is a tubular portion made of resin for housing said lighting circuit; and an outer casing which is a tubular portion for housing said inner casing, wherein said outer casing is a cylindrical portion having an inverse circular truncated cone shape and having an inner diameter and an outer diameter both decreasing toward said base, wherein said inner casing has a protrusion on an outer circumferential surface of said inner casing, said protrusion directly abutting an inner circumferential surface of said outer casing, and said protrusion positionally corresponding to a circuit device which is predetermined as generating a large amount of heat from among circuit devices included in said lighting circuit, and said protrusion has a linear structure extending in a circumferential direction of the outer circumferential surface of said inner casing.