Abstract:
A switch 1 includes a ceramic cylindrical tube 3, first and second end caps 5 and 7 that cover the open end in an axial direction of the ceramic cylindrical tube 3, a movable electrode 9 which slides easily on first end cap 5 and a fixed electrode 11 attached to second end cap 7. The ceramic cylindrical tube 3 is a ceramic fired body that contains 45 to 65% by weight of alumina and 35 to 55% by weight of crystallized glass. First and second end caps 5 and 7 are attached to both ends in the axial direction of the ceramic cylindrical tube 3. A low temperature metallizing layer is formed on the ends thereof, and a plating layer is formed on top of the metallizing layer where first and second end caps 5 and 7 are brazed.
Abstract:
A metal-ceramic composite is provided in which a solder layer and a ceramic member are held in contact with each other at an annular area extending along an entire circumference of an axial end surface of the ceramic member and having an average width W (mm), and in which the average width W and an outer diameter D (mm) of the ceramic member satisfy D≧30 and (⅙)×D≧W≧(D/30)+2.6.
Abstract:
A low cost and highly reliable vacuum circuit interrupter and a method of manufacturing the same improve production efficiency and vacuum tight sealing property of the vacuum circuit interrupter. In the vacuum circuit interrupter, within a sealed vacuum vessel 100 a pair of separable conductors in center axial direction of the sealed vacuum vessel composed of a stationary conductor 3 and a movable conductor 5 are disposed. The sealed vacuum vessel 100 is sealed in vacuum tightness in such a manner that an upper end portion 1A of a hollow cylindrical insulation body 1 is sealed with a flexible member 6 generally called a bellows and a metal end plate 7 by joining a movable conductor side 6A of the bellows 6 to the movable conductor 5 so as to permit separation of the movable conductor 5 from the stationary conductor 3 while maintaining the vacuum sealed condition in the vacuum sealed vessel 100, and by joining one end of the metal end plate 7 with the upper end portion 1A of the hollow cylindrical insulation body 1 and the other end thereof with a metal end plate side 6B of the bellows 6. A lower end portion 1B of the hollow cylindrical insulation body 1 is sealed with the stationary conductor 3 by itself.
Abstract:
A vacuum discharge device comprising an insulating envelop having metallic layers formed by a metallizing process respectively on the opposite ends thereof, electrodes disposed within the insulating envelop, and sealing members brazed respectively to the metallic layers. The insulating envelop is a hollow, cylindrical ceramic member having a substantially uniform wall thickness between each wavy inner ridges, or each crest of wavy ridges. The inner creeping length and outer creeping length of the insulating evelop are greater than the distance between the sealing members or between the metallic layers.
Abstract:
A vacuum interrupter (10) has a metallic member (11, 13) for a vacuum envelope and an insulating member (12a, 12b) for the vacuum envelope, made of unglazed insulating ceramics. A pair of separable stationary and movable contacts (24, 29) contained in the vacuum envelope. A movable lead rod (16) is rigidly secured to a movable disc-shaped electrode (30) which has the movable contact (29), extending outwardly of the vacuum envelope. Bellows secured in a vacuum-tight manner to the rod (16) and to the vacuum envelope. An impervious insulating film is coated adhesively on atmospheric-side surfaces of the insulating member (12a, 12b) and of the vacuum-tightly connected portion and vicinity thereof between the insulating member (12a, 12b) and metallic member (11, 13) for the vacuum envelope. Consequently, the vacuum envelope of the interrupter (10) is free from adsorbing moisture and pollutant, thereby preventing insulating performance of the envelope from lowering, and highly improving reliablity of vacuum-tightness of the envelope.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
A vacuum type electric circuit interrupter comprises a glass envelope, stainless steel end plates, a pair of relatively movable studs with a contact on each within the envelope, and shielding means within the envelope. Each stud and its associated contact are integrally formed of an alloy comprising by weight 0.4 to 0.6 percent tellurium, 0.007 to 0.012 percent phosphorus and the balance O.F.H.C. copper (oxygen free high conductivity copper which is 99.95 percent pure copper). The integrally formed stud and contact are subjected to a treatment wherein it is: raised slowly to 500*C. and held there for approximately 1/2 hour; exposed to ultra-pure hydrogen and raised slowly to about 900*C.; exposed to a vacuum and raised to about 975*C. to effect brazing of components thereto; lowered to about 500*C. in the vacuum and held there to cause effusion of certain gases; and cooled in the vacuum prior to final assembly.