Koito Manufacturing Company, Ltd.

Kunimasa Motiduki

Masakazu Nagasawa

Yukio Wakimizu

Masami Handa

An electrical discharge lamp device in which an ultraviolet filtering globe tightly encloses a sealed glass bulb of an arc tube containing a pair of oppositely disposed electrodes to thereby form a unitary body. The rear end part of the arc tube extending from the ultraviolet filtering globe is supported by an insulating base, and the forward end part of the arc tube is supported by a lead support extending forward from the insulating base. An extending part is formed on the front face of a base main body made of synthetic resin, and the rear part of the ultraviolet filtering globe is supported by the tubular extending part. In this construction, stress is not concentrated on the portion of the arc tube supported by the base main body of the arc tube, and hence the durability of the arc tube is improved.

Electrical discharge lamp with ultraviolet filtering globe having rear

An insulating base for a discharge lamp device which provides good insulation between a lead support connected to a front end lead of an arc tube and a lead disposed on the rear side of the arc tube. The insulating base includes a base main body formed of synthetic resin. The base main body is a disk-shaped injection molding which includes a lead support insertion hole in the form of a first longitudinal through hole for mounting a lead support supporting the front end portion of an arc tube and acting as a current path to a lead disposed on the front side of the arc tube, and a lead insertion hole in the form of a second longitudinal through hole for insertion of a lead disposed on the rear end side of the arc tube. The base main body is molded in such a manner that a separation wall area between the lead support insertion hole formed in the front surface of the base main body and the lead insertion hole faces molten resin injection gates provided in base main body molding metal molds, thereby preventing a weld portion from being produced in the separation wall area between the two holes.

Insulating base for discharge lamp device

A discharge lamp apparatus in which an insulating base for supporting a lead support base end portion maintains its dielectric strength over long periods of use, and which is simple to assemble. A lead support acting as a current path is projectingly provided on a front surface of a synthetic-resin insulating base, which is a lamp holder, a front end portion of an arc tube, which is a discharge lamp body, is supported by the lead support, a rear end portion of the arc tube is fixedly supported in an engagement concave portion formed in the insulating base, and the lead support is covered with a ceramic insulating cylindrical body. In accordance with the invention, a base end portion of the insulating cylindrical body is integrated with the insulating base through insert molding.

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Shizuoka, Japan

Kunimasa Motiduki