Hitachi, Ltd.

Katsumi Kuroda

Yoshitaka Kojima

Yoshimi Hakamata

Katsuhiro Komuro

Yukio Kurosawa

Noboru Baba

Toru Tanimizu

Ryo Hiraga

Tooru Tanimizu

Shigeru Kikuchi

Hitoshi Okabe

Shunkichi Endoo

Disclosed is a vacuum circuit breaker including a small-sized electrode structure capable of reducing deformation with age thereby enhancing the reliability and a vacuum bulb and a vacuum bulb electrode used for the breaker. In the vacuum circuit breaker, each of a fixed electrode and a movable side electrode includes an arc electrode made from particles of a refractory metal material, a high conductive metal material and a low melting point metal; an electrode supporting portion, made from the high conductive metal material, for supporting the arc electrode; a back conductor having a diameter smaller than the electrode supporting portion; and an external side connecting portion having a diameter larger than that of the back conductor. The arc electrode is integrated with the electrode supporting portion, back conductor, and external side connecting portion by the high conductive metal material, preferably, by melting of the highly conductive metal material.

Vacuum circuit breaker, and vacuum bulb and vacuum bulb electrode used therefor

A vacuum switch having a fixed side electrode unit and a movable side electrode unit mounted in a vacuum vessel. Each electrode unit includes an arc electrode, an arc electrode supporting member for supporting the arc electrode, a coil electrode and a conducting rod. Joining portions between the arc electrode and the arc electrode supporting member, the coil electrode and the conducting rod are integrally and directly formed metallurgically by solid phase diffusion using a hot isostatic process. A vacuum circuit breaker may be constructed incorporating the vacuum switch.

Vacuum circuit breaker with improved contact assembly

Growing community of inventors

Hitachi, Japan

Katsumi Kuroda