Hitachi, Ltd.

Japan Ae Power Systems Corporation

Daisuke Ebisawa

Makoto Hirose

Hiroaki Hashimoto

Masahiko Ono

Hisashi Urasaki

Shinji Seto

Hideo Kawamoto

Kenichi Okubo

Masanao Terada

Hajime Urai

Yasuhide Takeda

Riichi Nagao

Masayuki Uchiyama

Atsuji Watanabe

A switchgear driving device has a rod coupled to a movable electrode; an operation piston connected to the rod; and an operation cylinder in which an operation piston slides. A main control valve controls the pressure of the hydraulic oil in the operation cylinder. A turning-on pressure accumulation piston slides inside a turning-on pressure accumulation chamber; and a turning-on pressure accumulation spring imparts a driving force to the turning-on pressure accumulation piston to pressurize the hydraulic oil within the turning-on pressure accumulation chamber. A turning-off pressure accumulation piston slides inside a turning-off pressure accumulation chamber. A turning-off pressure accumulation spring imparts a driving force to the turning-off pressure accumulation piston to pressurize the hydraulic oil in the turning-off pressure accumulation chamber. A spring case accommodates the turning-on pressure accumulation spring and the turning-off pressure accumulation spring, wherein the turning-off pressure accumulation spring is arranged inside the turning-on pressure accumulation spring.

Hydraulic drive for a switchgear

Disclosed is an abrasion resistant material having low cost and excellent abrasion resistance, a puffer cylinder, and a puffer type gas circuit breaker. The abrasion resistant material includes: a base material which is formed of pure aluminum or aluminum alloy and has an unevenness structure formed on its surface; and an aluminum hydrated oxide film which is formed on the surface of the base material, wherein a surface of the aluminum hydrated oxide film is provided with an unevenness structure which is finer than the unevenness structure of the base material.

Abrasion resistant material, puffer cylinder, and puffer type gas circuit breaker

To provide a gas circuit breaker having a space-saving and highly reliable double motion mechanism with high design freedom. In a double motion mechanism of the gas circuit breaker, a driven side movable pin is communicated with a lever driven side hole cut in the opposite side with respect to a rotation axis of a lever. A round hole through which a driving side movable pin is inserted and an elongate hole through which the driven side movable pin is inserted are cut in the outside of the lever. A position retaining member to suppress rotation of the driving side movable pin about two axes vertical to a pin axis is provided. The driving side movable pin is moved in respective grooved cams with an operation of the driving side rod, to rotate the lever, drive the driven side connecting rod in an opposite direction to the driving side connecting rod, and drive the driven side arcing contact in an opposite direction to the driving side arcing contact.

Gas circuit breaker

The present invention includes a wear-resistant material including: a base material formed of pure aluminum or an aluminum alloy having a projection, and a depression in a pit-like shape on a surface thereof; and a coat including a dehydrate of a hydrated oxide of aluminum, the coat being formed on a surface of the base material. Further, the present invention including a method for producing a wear-resistant material including the steps of: forming a hydrated oxide coat of aluminum on a surface of the base material by a chemical conversion coating; and heating the hydrated oxide coat. Further, the present invention also includes a puffer cylinder and a puffer-type gas circuit breaker applied to the above wear-resistant material.

Wear-resistant material, method for producing the same, puffer cylinder and puffer-type gas circuit breaker

The present invention includes a wear-resistant material including: a base material formed of pure aluminum or an aluminum alloy having a finely asperity structure on a surface thereof; and a coat including a hydrated oxide coat of aluminum, the coat being formed on the surface of the base material. Further, the present invention including a puffer cylinder including: a finely asperity structure on an inner-wall surface thereof; and a coat including a hydrated oxide coat of aluminum, the coat being formed on the inner-wall surface of the puffer cylinder. The present invention also includes a puffer-type gas circuit breaker includes the above puffer cylinder.

Wear-resistant material, puffer cylinder, and puffer-type gas circuit breaker

A circuit breaker () formed with a sealed tank () having a breaker section and an operating mechanism () is laterally arranged in a lengthwise direction and is fixed to a frame (), and above the circuit breaker, main bus containers () are provided, substantially orthogonally to an axial direction of the circuit breaker (). Operating mechanism-side working space (B) and breaker section-side working space (C) are provided respectively above the operating mechanism () and the sealed tank (), and a hand hole () is provided on an upper surface of the sealed tank (). A connecting pin () is provided in a link mechanism connecting the operating mechanism () and the movable contact (), and an operating mechanism-side working hole for accessibility to the connecting pin () from the operating mechanism-side working space (B) is provided.

Gas-insulated switchgear

Disclosed is a hydraulic operating apparatus for switch with which it is possible to constantly obtain a stable interrupting performance at the time of high-speed successive operations. Closing and interrupting pressure accumulators comprise closing and interrupting pressure accumulation pistons, and closing and interrupting pressure accumulation springs for biasing the closing and interrupting pressure accumulation pistons in pressure accumulation directions, respectively. The closing and interrupting pressure accumulation springs exert, on the closing and interrupting pressure accumulation pistons, forces corresponding to received pressures acting on the closing and interrupting pressure accumulation pistons from closing and interrupting pressure accumulation chambers in a steady state. The closing pressure accumulator and the interrupting pressure accumulator are independently constituted for closing and for interrupting, respectively.

Hydraulic operating apparatus for switch

In a hydraulic pressure actuating apparatus for a circuit breaker, contacts of the circuit breaker have a moving contact and a stationary contact for turning on/off current. A shaft, at an end portion of which is attached the moving contact, and at the other end of which is attached a piston, is received within a cylinder. A directional control valve exchanges oil pressure for actuating the piston. For changing over the directional control valve, pilot valves are provided. Each pilot valve has a pair of valve bodies, each opposing to each other, and springs. One of the valve bodies is able to stroke up to contact with the valve body of the other valve body, therefore giving no ill influences upon actuating time, even if drawback occurs in the pilot valves in the hydraulic pressure actuating apparatus for the circuit breaker.

Growing community of inventors

Tokyo, Japan

Daisuke Ebisawa