A gas-insulated switchgear comprising bushings mounted to and passing through a vessel wall of the hermetic vessel, each having an outer end connected to an insulated bus conductor at the outside of the hermetic vessel and an inner end connected to the electric device within the hermetic vessel Each of the bushings has a central axis that is perpendicular to the common axis of the electric device and spaced apart from each other in the direction of extension of the common axis and shifted by a predetermined angle with respect to each other about the common axis The flat bushing mounting vessel walls are tilted from inside to outside relative to other portion of the wall

Gas insulated switchgear

A power switch module designed to be mounted in gas-filled containers of gas-insulated switchgear is provided, wherein each vacuum switch tube of the power switch has a corresponding rectilinearly movable actuating rod leading into the gas-filled container through a bellows-type seal. The power switch module includes two insulating support devices arranged symmetrically on a partition, between which the corresponding vacuum switch tubes supported by a pole support device and a pole head device. Such power switch modules are used in gas-insulated switchgears.

Vacuum switch assembly including housing insulating support

A gas circuit breaker comprising: a sealed tank; two breaking sections disposed in the sealed tank; a bracket to support movable parts of the breaking sections while enabling switching operation of the movable parts; an insulation cylinder to support the bracket through an electric field relaxation shield; an insulated operating rod disposed in the insulation cylinder movably in the axial direction and an end thereof is connected to an actuator; and a link mechanism connected to other end of the insulated rod and transmits drive force from the actuator to the movable parts of the breaking sections, wherein the electric field relaxation shield is provided with out-side groove and in-side groove on the insulation cylinder respectively, and the out-side groove and in-side groove are formed openings at the link mechanism side respectively, and end of the in-side groove is extended to near the outer surrounding of the insulated operating rod.

Gas circuit breaker

The invention provides a method for performing electroless nickel plating on the surface of aluminum nitride ceramic, belonging to the ceramic thin-film metallization field The method comprises the following specific steps: 1) polishing the surface of aluminum nitride with a machinery; coarsening the aluminum nitride substrate with mixed acid or alkali, completely cleaning away the residual acid or alkali; 3) sensitizing the coarsened substrate in stannous chloride solution, activating in palladium chloride solution or performing activation without palladium; 4) weighting a certain amount of nickel sulphate, sodium hypophosphite, sodium citrate, sodium acetate, lactic acid, thiourea and sodium dodecyl sulfate in sequence to prepare a chemical plating solution; and 5) adjusting the pH value of the solution to 40-60 with acid or alkali, heating the solution to 70-95 DEG C, and placing the prepared substrate in the solution to perform electroless nickel plating The invention is characterized in that the electroless nickel plating can be performed on the surface of the aluminum nitride ceramic substrate which is difficult to plate; and a certain amount of surfactant is added so that the plating becomes denser and smoother, the binding force between the plating and the substrate is increased, and the solderability of the plating is better

Method for performing electroless nickel plating on surface of aluminum nitride ceramic

A vacuum switch 1 includes a grounded vacuum vessel 2. The reliability of monitoring and measuring the vacuum pressure is improved by providing a vacuum pressure measuring terminal 30 at a side plane of the vacuum vessel 2 such that a main circuit 13 and the measuring terminal 30 are electrically separated from each other.

Vacuum insulated switching apparatus

A gas-insulated switchgear in which a vacuum switch main contact assembly constituted by a fixed contact element and a movable contact element is enclosed in a vacuum tank The vacuum switch has a movable terminal fixed at its one end to the movable contact element and is led out from the vacuum tank through a bellows The vacuum switch is enclosed in a gas tank filled with an insulating gas having gas pressure not less than the atmospheric pressure The main contact assembly of the vacuum switch is operated so as to perform electrical connection and disconnection functions, through a transmission mechanism, by a driver provided outside of the gas tank A driving rod transmits an operating force of the driver to the movable terminal of the vacuum switch The driving rod is led out from the gas tank through another bellows mounted to the gas tank

Gas-insulated switchgear including a vacuum switch, operating mechanism and plural bellows

An improved vacuum valve including an insulating container and an arc shield held in the insulating container, wherein a protrusion is formed on either the outer cylindrical surface of the arc shield or on the inner surface of the container A detecting electrode is set confronted with the outer surface of the insulating container with an air gap therebetween, and is grounded through a current sensor The current sensor detects a discharge current which is induced through the protrusion when the degree of vacuum of the vacuum valve is reduced, to output a detection signal In response to the detection signal, a signal processing unit outputs an alarm signal indicating the reduction in the degree of vacuum of the vacuum valve Thus, while the vacuum valve is in operation, its vacuum reduction can be positively detected with the vacuum valve maintained unchanged in reliability

Method and apparatus for detecting a reduction in the degree of vacuum of a vacuum valve while in operation

The method involves maintaining a function protection shield (4) at the same potential as a movable (3) and a stationary (2) electrode and detecting a discharge current induced by a bulge (10) in the outer surface of the shield or in the inner surface of an insulating container (5) when the degree of vacuum is reduced. The discharge current is detected by a current sensor (14) and used as a measure of the reduction in the degree of vacuum of the vacuum switching valve (1). USE/ADVANTAGE - For use with valve in vacuum overload circuit or vacuum protection switch. Enables reduction in degree of vacuum of valve to be determined during operation without degrading reliability of valve.

Detecting reduction in degree of vacuum of vacuum switching valve - determining discharge current caused by bulge, e.g. in protective shield, whilst holding shield at same potential as electrodes

PURPOSE:To provide a display device that can be used in common even when the rated current of a main circuit differs by detecting the first converter output current for activating the overcurrent relay of a circuit breaker by a second converter, and whereby displaying the detection result. CONSTITUTION:A first converter 4A is interposed on a main circuit 2A, and the overcurrent relay 5 of a circuit breaker 1 is activated through the converter 4A. The output current of the converter 4A is detected by the second converter 70 of a current display device 60, and is displayed by a display part 90 through a converter 9. In this structure, the display device of a circuit breaker that can be used in common even when the rated current of the main circuit differs, is thus provided.

Method and device of displaying electric capacity of circuit breaker

PURPOSE:To detect the vacuum leak of a vacuum valve in use without reducing the reliability of the vacuum valve itself. CONSTITUTION:A projection 10 is formed on the outer circumferential surface of the arc shield 4 of a vacuum valve 1, and a detecting electrode 11 is arranged on the outside of an insulating vessel 5 through an air gap G. The detecting electrode 11 is earthed through a current sensor 14, which detects a discharge current generated in the projection 10 when the vacuum valve 1 has a vacuum leak, and a signal processing device 15 notifies of the vacuum leak of the vacuum valve 1.

Toshio Kobayashi

Papers

Gas-insulated switchgear including a vacuum switch, operating mechanism and plural bellows

Method and apparatus for detecting a reduction in the degree of vacuum of a vacuum valve while in operation

Detecting reduction in degree of vacuum of vacuum switching valve - determining discharge current caused by bulge, e.g. in protective shield, whilst holding shield at same potential as electrodes

Method and device of displaying electric capacity of circuit breaker

Method and device for detecting vacuum leak of vacuum valve