Patent ID: 6649856
Filing Date: 2003-11-18
Classification: C04B,H01B,H01H

Abstract:
A vacuum switch comprising:a metal and ceramic assembly having a tubular member made of ceramic, and a tubular arc shield made of metal, disposed inside the tubular member and soldered to the tubular member, the tubular member having on an outer circumferential surface a glaze layer, the glaze layer being made of a glaze comprising Si in an amount of 60 to 74% by weight when calculated in terms of SiO2 and Al in an amount of 16 to 30% by weight when calculated in terms of Al2O3; a pair of cover members for closing axial ends of the tubular member to define a shielded space; a stationary electrode extending through one of the cover members and having a stationary terminal portion outside the shielded space and a stationary switch contact portion disposed inside the shielded space; and a movable electrode extending through the other of the cover members and movable axially of the tubular member, the movable electrode having a movable terminal portion disposed outside the shielded space and a movable switch contact portion disposed inside the shielded space and movable toward and away from the stationary switch contact portion; the arc shield being disposed so as to surround the stationary switch contact portion and the movable switch contact portion.