HIGH PRESSURE DISCHARGE LAMP, LIGHTING DEVICE, AND VEHICLE HEADLIGHT

摘要

PROBLEM TO BE SOLVED: To provide a small high pressure discharge lamp in which the insulation between a high potential side and a low potential side is assured for excellent starting property.

SOLUTION: The high pressure discharge lamp assures insulation between a high potential side and a low potential side of the high pressure discharge lamp where a mouthpiece is attached to one end of a bulb and a lamp socket to which the lamp is attached/detached, using a packing 4 of electrically- insulating material which can elastically deform. The socket comprises a receiving surface 57 around a tubular insulating wall 55 in which a high voltage side feeding terminal 25 is disposed. A receiving surface cover 4b of the packing 4 is pressed and held by the receiving surface 57 at the tip surface of an engaging cylinder of the mouthpiece. Multiple projections 58 are provided to the receiving surface 57 for tight contacting to the receiving surface cover 4b as well as for a longer creepage distance. The projections 58 comprise one end 58a on the tubular insulation wall 55 and the other end 58b circumferentially dislocated against one end, and are so formed as to cross the radial direction whose center is the tubular insulation wall 55.

COPYRIGHT: (C)2004,JPO