An object is to enhance direct-current insulating performance of a gas-blast circuit breaker. The gas-blast circuit breaker includes: a pair of main contacts disposed in a gas tank to face each other and configured to operate for opening and closing a circuit; a pair of arc contacts disposed to face each other and configured to operate for opening and closing the circuit, the arc contacts being disposed coaxially with the main contacts at locations close to the centers of the main contacts, respectively; and an elastic electrically conductive material disposed on an outer surface of an insulating nozzle facing an inner surface of one of the main contacts.

There is provided a gas circuit breaker that can spray arc-extinguishing gas to arcs while preventing a spraying velocity from being reduced and can efficiently and more surely extinguish the arcs that have been generated in a scatteredly around electrodes. A gas circuit breaker 1 includes an insulation nozzle 23 that guides arc-extinguishing gas to an arc between the first arc contactor 21 and a second arc contactor 41 when a trigger electrode 31 becomes an opened state relative to a first arc contactor 21. A second arc contactor 41 has an opening 41a for spraying the arc-extinguishing gas, and the opening 41a is closed by the trigger electrode 31 in the first half of a current breaking action, and is opened by separation of the trigger electrode in the latter half of the current breaking action. An opening area of a first exhaust port 41b formed between the second arc contactor 41 and the insulation nozzle 23 for exhausting the arc-extinguishing gas is 0.2 times or more and two times or less of an opening area of the opening 41a of the second arc contactor.

A gas-insulated low- or medium-voltage switch for system voltages within 1 to 52 kV and for up to 2000 A rated current includes first and second contacts being movable in relation to each other along an axis of the switch and defining a quenching region in which an arc is formed during a current breaking operation; and an arc-extinguishing system for extinguishing the arc during the current breaking operation. The arc-extinguishing system may include a pressurization system with a puffer chamber, and a nozzle system connecting the pressurization system with the quenching region, the nozzle system having a nozzle at its outlet for blowing the pressurized quenching gas onto the arc formed in the quenching region during the current breaking operation; and a swirling device configured for generating a subsonic swirl flow of a quenching gas onto the quenching region during the current breaking operation, wherein the swirling device is arranged at an entrance of the nozzle system. The arc-extinguishing system further includes a swirling device configured for generating a subsonic swirl flow of a quenching gas onto the quenching region during the current breaking operation, wherein the swirling device is arranged at an entrance of the nozzle system.

A gas-insulated high-voltage switching device which includes an arcing contact arrangement having a first arcing zone member and a second arcing zone member that are movable relative to one another along an axis. An auxiliary nozzle surrounds at least a part of a second arcing contact unit and has an auxiliary nozzle throat having an axial extension and allowing passage at least of an end of the first arcing contact unit. A main nozzle throat has an axial extension sideways of the auxiliary nozzle throat and allows passage at least of the end of the first arcing contact unit. A cross-sectional area of the main nozzle throat is substantially decreasing in the direction away from the auxiliary nozzle throat so as to form a substantially converging duct for the flow of an arc-extinguishing gas.

In order to solve the above-described problems, a gas circuit breaker of the present invention has an insulating nozzle disposed so as to cover an inner surface of a coupling member such that an end surface of the coupling member and an end surface of the insulating nozzle form one surface (the end surface of the coupling member is flush with the end surface of the insulating nozzle), in order to suppress contact between a high-temperature and high-pressure gas generated by an arc and the coupling member coupling the insulating nozzle and a driving rod.

A nozzle with an electric arc-blast having a median part of a first dielectric material and two end parts. The nozzle includes an insert of a second dielectric material, chosen from among: a composite material including a fluorocarbon polymer matrix and inorganic filler A chosen from among a sulfur, a ceramic and an oxide (SiO2, TiO2, Al2CoO4, ZnO, BaTiO3 and P2O5), in a percentage weight ranging between 0.1% and 10%, and/or at least one inorganic filler B (a graphite, a mica, a glass and a fluoride), in a percentage weight ranging between 5% and 50%, and a ceramic material including compound(s) (a carbide, a boride and an oxide).

An interrupter unit for a circuit breaker has two electrically conductive arcing contact pieces, which can be moved relative to one another along a switching path. An insulating nozzle has a nozzle channel through which the switching path runs. A heating volume is connected to the nozzle channel. A separating housing divides the heating volume into a cold gas region and a hot gas region. A cold gas duct runs through a nozzle channel end section of the nozzle channel and is connected to the cold gas region. A hot gas duct runs through the nozzle channel end section and is connected to the hot gas region.

A circuit breaker, comprising an enclosure comprising: at least two arcing contacts that are movable axially relative to each other, between an open position of the circuit breaker in which the arcing contacts are separated from each other and a closed position of the circuit breaker in which the arcing contacts are in contact with each other; and a gas inlet configured to blow an arc-control gas in order to interrupt an electric arc that is likely to form during movement of the arcing contacts from the closed position to the open position of the circuit breaker, wherein the arc-control gas comprises at least 80% of carbon dioxide; wherein the enclosure further comprises an adsorbing material, which adsorbs carbon monoxide that forms after ionization of the carbon dioxide during arcing, said adsorber being a metal-organic framework comprising nickel and/or iron.

A gas circuit breaker includes: a fixed arc contact extending along an operating axis; a moving arc contact allowed to move to a position where the moving arc contact contacts the fixed arc contact and a position where the moving arc contact is separated from the fixed arc contact; a frame forming a puffer chamber around the moving arc contact; a nozzle having a cylindrical shape centered on the operating axis, the nozzle being fixed to the frame and projecting in a direction toward the fixed arc contact from the moving arc contact; and an arc extinction assisting portion provided on an inner surface of the nozzle and made of an ablation material. The nozzle and the arc extinction assisting portion are provided with a fall-off preventing portion to prevent the arc extinction assisting portion from falling off the nozzle.

The present invention relates to a device for interrupting non-short circuit currents only, and in particular relates to a disconnector, more particularly high voltage disconnector, or to an earthing switch, more particularly make-proof earthing switch, and further relates to a low voltage circuit breaker. The device comprises at least two contacts movable in relation to each other between a closed state and an open state and defining an arcing region, in which an arc is generated during a current interrupting operation and in which an arc-quenching medium comprising an organofluorine compound is present. According to the application, a counter-arcing component is allocated to the arcing region, the counter-arcing component being designed for counteracting the generation of an arc and/or being designed for supporting the extinction of an arc.