The gas-circuit-breaker includes a container, opposing part, movable-part, and nozzle. An arc-extinguishing gas fills the container. The opposing-part is housed in the container and includes an opposing-arc-contact and an exhaust stack. The movable-part is housed in the container and includes a movable-arc-contact coming in contact with the opposing-arc-contact in a connected-state and separating from the opposing-arc-contact in an open-state; and a pressure-accumulation-part where an arc-extinguishing gas pressure increases. The nozzle is housed in the container and includes a space where arc-discharge occurs between the movable-arc-contact and the opposing-arc-contact. The nozzle includes a middle-part where the opposing-arc-contact is inserted and one or more jet-holes that eject, toward the space, partial arc-extinguishing gas flowing in from a flow-passage between the pressure-accumulation-part and the middle-part. The arc-extinguishing gas whose pressure increases in the pressure-accumulation-part flows into the space via the flow-passage and the jet-holes to extinguish the arc-discharge.

The present disclosure relates to switchgear. Various embodiments may include medium- or high-voltage switchgear with a gas-tight insulating space. For example, a switchgear may include: a gas-tight insulating space where an insulating gas is kept above atmospheric pressure and two switching contacts in the space. At least one of the contacts may movable with respect to a nozzle. The insulating gas may include a mixture of at least 90% by mass of nitrogen and oxygen or nitrogen and carbon dioxide. The nozzle may include a plastic with at least 65% by mass in total of the elements carbon, nitrogen, and oxygen.

A pair of fixed arc electrodes are arranged facing each other within a sealed container that is filled with arc-extinguishing gas 1. There are provided: a compression puffer chamber for accumulating pressurized gas that is obtained by elevating the pressure of the arc-extinguishing gas; and an insulated nozzle that directs the pressurized gas towards the arc discharge from the compression puffer chamber. A buffer chamber is provided, in which hot exhaust gas generated by the heat of the arc discharge is temporarily accumulated. A pressurized gas through-flow space is provided, communicating with the compression puffer chamber. In the pressurized gas through-flow space, an opening/closing section prevents inflow of hot exhaust gas by assuming a closed condition during the earlier half of the current interruption period, and in the latter half of the current interruption period the opening/closing section 41 is opened to allow flow of pressurized gas.

The invention relates to an electric arc-blast nozzle for a circuit breaker comprising a middle portion forming a throat defining internally an axial passage for interrupting an electric arc, and two end portions extending on either side of the middle portion and being designed to receive respective arcing contacts and that are movable axially relative to each other.

The middle portion and the two end portions are made of a same dielectric material obtained from a composition consisting of a fluorocarbon polymer matrix and of at least one oxide, the oxide(s) being present in a proportion by weight lying in the range 11% to 50%, relative to the total weight of the composition.

The invention also relates to a circuit breaker including such a nozzle.

The gas circuit breaker includes a sealed container filled with an arc-extinguishing gas, a pair of fixed arc electrodes arranged in the sealed container to be opposite to each other, a trigger electrode movably arranged between the fixed arc electrodes and generating an arc discharge according to movement, a pressurization chamber pressuring and increasing a pressure of the arc-extinguishing gas with pressurization means, and a pressure accumulation chamber in communication with the pressurization chamber and accumulating the pressurized arc-extinguishing gas. The trigger electrode switches the pressure accumulation chamber into a closed state or an open state. The pressure accumulation chamber is switched to the closed state in a first half of breaking of the electric current, and the pressure accumulation chamber is switched to the open state in a latter half of breaking of the electric current. The arc-extinguishing gas in the pressure accumulation chamber is guided to the arc discharge.

A gas-insulated high or medium voltage circuit breaker includes: a first arcing contact and a second arcing contact, whereby at least one is axially movable along a switching axis, thereby forming an arc between the first arcing contact and the second arcing contact in an arcing region, a buffer cylinder including a channel directed to the arcing region and/or a nozzle for blowing during the breaking operation an arc-extinguishing gas to the arcing region; a first enclosure associated to first arcing contact substantially sur-rounding the buffer cylinder and arranged slidable in respect to the buffer cylinder and/or a second enclosure substantially surrounding the nozzle and arranged slidable in respect to the nozzle; and a labyrinth structure provided in the first enclosure and/or in the buffer cylinder between the first enclosure and the buffer cylinder and/or in the second enclosure and/or in the nozzle between the second enclosure and the nozzle.

Gas-insulated high voltage puffer breaker comprising a puffer unit with a movable piston running in a puffer cylinder and delimiting a puffer volume. A piston and a first contact member are attached to a piston stem. A piston and a first contact member are attached to a piston stem. An electric arc is extinguishable in an arcing zone when the first contact member moves from a first position to a second position. The puffer volume is fluidly connected to a gas nozzle by a gas channel such that the puffer volume comprises the gas channel as well as a portion of the puffer cylinder. The gas channel is provided radially outside of the puffer cylinder between a puffer cylinder wall delimiting the puffer cylinder and a wall structure of the puffer unit.

A gas circuit breaker including a pair of main contacts is openable inside an insulating tank. A pair of arc contacts is arranged on the inner side of the main contacts, and a puffer cylinder has the main contacts and the arc contacts at an end. A puffer chamber is formed inside the puffer cylinder, and a puffer piston is provided on the inner periphery of the puffer cylinder. An insulating nozzle part is mounted on an end of the puffer cylinder to surround the arc contact. The insulating nozzle part includes a split nozzle base part and a split nozzle end part, and the split nozzle base part has a throat part.

Provided herein is an electric arc-blast nozzle for a circuit breaker comprising a median part internally defining an axial electric arc cut-off passage and formed with a first dielectric material, first and second end parts formed with the first dielectric material and extending on either side of the median part and being intended to receive first and second arc contacts being axially moveable in relation to each other. The nozzle further comprises a sheath that is disposed on the external surface of the first end part and on a portion of the external surface of the neck-forming median part, said portion having the same radial external section than the first end part, is formed with a second dielectric material different from the first dielectric material and is obtained from a second composition comprising a thermoplastic polymer chosen from either a polysulfone or a polyetherimide, but not comprising fibrous reinforcements.

A switching configuration includes a first switching contact set having a rated current contact piece and an arcing contact piece. The arcing contact piece and the rated current contact piece of the first switching contact set are movable relative to one another through a transmission mechanism. The arcing contact piece is supported by a support element on a contact carrier of the rated current contact piece. The transmission mechanism has a transmission mechanism chassis which is supported, particularly directly, on the contact carrier.