Hitachi, Ltd.

Naoki Sumiya

Shigeru Yumiyama

Atsushi Saeki

Akira Toba

Rikio Goto

Norikazu Sanuga

Between a relay terminal of a direct current motor and a contact terminal of an electromagnetic switch, there is provided a fuse which is melted to cut off an electric current upon reaching a predetermined temperature. By properly setting the predetermined temperature at which the fuse melts, it is possible to make the fuse heated to a high temperature and melted in a relatively short time to cut off the electric current in the event of, for example, a continuous operative condition caused due to such a failure as fusion adhesion of a movable contact point with a B-terminal and an M-terminal or fusion adhesion of a contact point mechanism outside a starter, or an overcurrent supply condition caused upon a rotor being locked.

Starter equipped with current interruption mechanism

In a permanent magnet field starter motor, a ring shaped enlarged portion is formed at an end of a yoke and has an inner diameter Da which is larger than an inner diameter of the yoke. The inner diameter Da of the enlarged portion is at least as large as an outer diameter Db of a brush member holder plate which is inserted to an inner side of the enlarged portion, so that the radial position between the yoke and the brush member holder plate is directly aligned. A cut-out groove is formed on the yoke for inserting a bush member. The bush member is inserted into the cut-out groove, so that a thrust direction position of an outside portion lead wire, a lead terminal, and a lead wire is determined. A projection formed on the brush member holder plate has a width Wb which is at least as large as the width Wa of the cut-out groove. By inserting projection into the cut-out groove, the circumferential position between the yoke and the brush member holder plate is aligned.

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Hitachinaka, Japan

Naoki Sumiya