Vacuum circuit interrupter

A vacuum interrupter for electric power having a vacuum vessel into which a pair of electrode holders each having an electrode contact brazed to the end thereof are in contact with each other when the device is closed and are separated from each other when the device is open. The vacuum vessel comprises: (a) an insulating envelope made of ceramic or crystallized glass having a metallized layer at each end thereof; (b) a first metallic end plate made of copper to the periphery of which one metallized layer of the insulating envelope is brazed; (c) a second metallic end plate made of copper to the periphery of which the other metallized layer of the insulating envelope is brazed; (d) an arc shielding member located within the insulating envelope so as to surround the pair of electrode contacts and be brazed to the second metallic end plate at one end thereof; and (e) a bellows located within the arc shielding member brazed to the electrode holder at one end thereof and to the second metallic end plate at the other end thereof. Both the first and second metallic end plates are made of copper, and are annealed during the brazing operation so that they are easily deformed plastically, whereby thermal stress generated between the end plates and the insulating envelope is absorbed into these plastically deformable end plates and the insulating envelope and brazed joints are not destroyed.