Kabushiki Kaisha Meidensha

Kabushiki Kaisha Gemvac

Gemvac

Junichi Warabi

Shinzo Sakuma

Yukio Kobari

Yutaka Kashimoto

Hidemi Kawaguchi

Yoshiyuki Kashiwagi

Hifumi Yanagisawa

Masayuki Kano

Eiji Umeya

Katsuaki Senba

A vacuum interrupter, an envelope of which includes a pair of electrical lead rods of copper or copper-based alloy, one lead rod being brazed vacuum-tight to one end plate via a first tubular sealing member fitted onto one rod, and a bellows surrounding another lead rod, an outer end of the bellows being joined vacuum-tight to another end plate and an inner end of the bellows being brazed vacuum-tight to the other lead rod via a second tubular sealing member fitted onto the other lead rod. Each sealing member is made of an iron-based alloy and has an inner wall including a groove retaining solid brazing metal and two vacuum-tight brazing surfaces opposing each rod across a small clearance. The molten brazing metal permetates through the clearance due to wetablility and capillary action without erodingly diffusing into the opposing surfaces of the lead rods and the first and second sealing members.

Vacuum interrupter

A vacuum interrupter has a hollow metallic cylinder, insulating end plates made of inorganic insulating material and connected to the opposite ends of the metallic cylinder, stationary and movable lead rods which extend into the metallic cylinder through the insulating end plates and which support separable electrical contacts, a bellows connecting the movable lead rod to the corresponding insulating end plate, and auxiliary sealing members which connect the metallic cylinder to both the insulating end plates by means of brazing. At least one of each pair of members to be brazed has a groove for solid brazing material which is closed from the vacuum chamber of the interrupter. The vacuum interrupter facilitates arrangement of the solid brazing material in a temporary assembly step and greatly reduces the amount of vaporized brazing material dispersed into the vacuum chamber of the interrupter in a vacuum brazing step. Thus, the interrupter is provided with improved dielectric strength.

A vacuum circuit interrupter includes a cylinder made of a metal relatively easy to deform plastically, and first and second insulating disks closing the ends of the metallic cylinder to form therewith an evacuated envelope. A stationary rod enters the envelope through the first disk in such a manner as to provide a seal therewith. A movable conductive rod movably enters the envelope through the second disk. A bellows is fixed at its one end to the movable rod and at its other end to the second disk in such a manner as to provide a seal about the movable rod to allow for movement thereof without impairing the vacuum inside the envelope. Stationary and movable electrodes are connected to the stationary and movable rods respectively in such a manner as to engage and disengage with each other according to the movement of the movable rod.

Vacuum circuit interrupter

An evacuated envelope includes a cylindrical housing made of a metallic material, disc-shaped upper and lower end plates made of ceramic and stationary and movable contact rods. The envelope of the vacuum interrupter is manufactured by brazing the end plates to the housing by using a sealing member made of a hermetically deformable metallic material which deforms by thermal stress generated during a cooling process after hermetic brazing. Sealing means of the envelope is provided with surface-to-surface sealing between the seal member and the cylindrical metallic housing or the disc-shaped end plate in order to enhance the sealing performance. The envelope is hermetically sealed by deforming the sealing member after brazing the sealing member to the housing in order to further enhance the sealing performance. The sealing member further comprises a stress absorbing means provided with a curved portion for absorbing thermal and mechanical stress.

A vacuum interrupter comprises a vacuum vessel 3, a pair of electrodes 4, 5 disposed within the vacuum vessel 3 so that one is in contact with the other or away therefrom, and a bellows 17 for allowing a movable electrode 5 to be movable with an air-tight relationship. The vacuum interrupter further comprises an auxiliary member 21 disposed between the bellows 17 and the vacuum vessel 3, thereby making it easy to effect the positioning of the bellows 17 and a brazing material. The auxiliary member 21 further serves as a member for absorbing and relaxing an impact appearing at the bellows when the vacuum interrupter is placed in an operational condition.

The invention provides a vacuum interrupter in which an evacuated envelope includes a cylindrical housing made of a metallic material, disc-shaped upper and lower end plates made of inorganic insulating material and stationary and movable contact rods. The envelope of the vacuum interrupter is manufactured by brazing the end plates to the housing by using a sealing member made of a plastically deformable metallic material which is deformed by thermal stress generated during a cooling process after hermetic brazing. The coefficient of the housing differs from that of the upper and lower end plates. According to the present invention, the sealing performance can be enhanced, even when the thermal coefficient of the housing differs from those of the end plates, since the sealing member is used.

A vacuum circuit interrupter includes an evacuated envelope composed of a plastically deformable metallic cylinder and first and second insulating disks closing the opposite ends of the cylinder. Stationary and movable conductive rods project coaxially through the first and second disks respectively. Stationary and movable electrodes are connected to the stationary and movable rods in such a manner as to engage with each other when the movable rod moves toward the stationary rod and disengage with each other when the movable rod moves away from the stationary rod. A bellows surrounds the movable rod inside the envelope and is fixed at its one end to the movable rod and at its other end to the second disk in such a manner as to provide a seal about the movable rod to allow for movement thereof without impairing the vacuum inside the envelope. A first conductive shield surrounds the stationary rod inside the envelope. The first shield is fixed to the first disk in such a manner as to be isolated electrically from the stationary rod and the metallic cylinder. A second conductive shield surrounds the bellows. The second shield is fixed to the second disk in such a manner as to be isolated electrically from the movable rod and the metallic cylinder.

A vacuum interrupter has a bell-shaped metal casing made of copper or stainless steel with a copper, ring-shaped stress reduction member sandwiched between an open end of the casing and the outer periphery of a ceramic insulation disk. Since copper is plastically deformable, thermal stress generated during cooling down to room temperature following brazing of the metal casing to the ceramic insulation disk is substantially reduced, resulting in increased brazing strength so that the wall thickness of the casing can be increased. Further, since copper and stainless steel are not ferromagnetic materials, it is possible to reduce eddy currents and magnetostrictive vibration in the casing.

A vacuum interrupter envelope including a housing made of non magnetic metallic material with end plates fabricated from insulating material in the form of a ceramic or crystallized glass. Auxiliary sealing members are made of metallic material which are deformable in response to thermal stress at high temperture.

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.

A vacuum power interrupter is constituted by a vacuum vessel (21) consisting of a bell shaped metal casing (20) having substantially the same coefficient of thermal expansion as that of ceramic, and an insulating circular end plate (19, 19a), having a circular bore (24) in the center thereof, hermetically brazed to the opening end of the casing. The vacuum power interrupter comprises stationary and movable contact rods (38, 35), each having an electrical contact (22, 23) on the one end thereof, aligned in the axial direction of the vacuum vessel so that the latter is movable relative to the former, an arc-shield member (30) disposed within the vacuum vessel so as to surround electrical contacts, and a bellows (33) having one end hermetically brazed to the one end of the movable contact rod, and the other end hermetically brazed to the inner circumferential surface of the insulating end plate through an annular extended portion of the arc-shield member.

Vacuum power interrupter

An arc-shield supporting structure of a vacuum power interrupter is disclosed which comprises a hollow cylindrical supporting means having a turnover end portion embedded in the inner wall of the insulating envelope, and a connecting means one end of which is fitted over the supporting means while the other end of which is fixed to the arc-shield member.

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Shizuoka, Japan

Junichi Warabi