JP2009076377A5 - - Google Patents

Claims (3)

An LED light source, a heat sink for mounting the LED light source and dissipating heat generated when the LED light source is turned on, and a light emitted from the LED light source disposed so as to cover the LED light source The LED lamp unit includes a reflector that reflects toward the projector and a projection lens that irradiates the reflected light from the reflector while converging the reflected light forward , and the LED lamp unit is on the heat sink side of the LED lamp unit. The LED lamp unit is mounted on a vehicle with the upper side facing up . The LED lamp unit includes a shutter that forms a cut-off line between the reflector and the projection lens by blocking a part of the reflected light from the reflector, and the heat sink and the shutter are arranged on the projection lens. Located on different sides with respect to the plane including the optical axis, the reflector is composed of three reflector areas, a first reflector area, a second reflector area, and a third reflector area having an inner peripheral surface as a reflection surface. The first reflector region covers the LED light source so that the vicinity of the LED light source is the position of the first focal point, and the inner periphery is an elliptical surface having the vicinity of the upper end of the shutter being the second focal point position. A long axis including a first focal point and a second focal point is located substantially collinear with an irradiation axis of the lamp unit, and the second reflector region An ellipsoidal surface having the vicinity of the LED light source as the first focal position so as to cover the LED light source, and the position near the first focal point on the inner peripheral surface of the third reflector region as the second focal position. The third reflector region has a first focal point position in the vicinity of the second focal point on the inner peripheral surface of the second reflector region, and a second region in the vicinity of the upper end portion of the shutter. The LED lamp unit according to claim 1, wherein the LED lamp unit has an inner peripheral surface composed of an elliptical surface serving as a focal point . In the heat sink, a base portion on which the LED light source is placed and a plurality of fin portions are integrated, and the base portion and the LED light source placed on the base portion face rearward with respect to the irradiation axis of the LED lamp unit. The fin portion of the heat sink has both lateral ends extending substantially perpendicular to the base portion, and the tip portion of the fin portion on the side facing the base portion is substantially the same as the base portion. The length of the fin part located back is long with respect to the length of the fin part located in front, extending in parallel and divided into two, The claim 1 or 2 characterized by the above-mentioned. The LED lamp unit according to Item.