Abstract: An insulation rod cover is fitted to an end portion of a puffer shaft and the insulation rod cover is fitted to a circuit-breaker side coupling pin coupling between a puffer shaft and an insulation rod, thereby allowing the insulation rod cover to be held at a joint between the puffer shaft and the insulation rod. In a first half of a circuit-breaking operation, the insulation rod cover is positioned in the exhaust cylinder and the exhaust of the hot gas from the puffer shaft is suppressed to increase the pressure of an extinguishing gas to be sprayed onto the arc. In a last half of the circuit-breaking operation, the insulation rod cover is positioned in a guard cylinder to promote the exhaust of the hot gas from the puffer shaft as well as to suppress the flow of the hot gas into the insulation cylinder.

Abstract: An insulation rod cover is fitted to an end portion of a puffer shaft and the insulation rod cover is fitted to a circuit-breaker side coupling pin coupling between a puffer shaft and an insulation rod, thereby allowing the insulation rod cover to be held at a joint between the puffer shaft and the insulation rod. In a first half of a circuit-breaking operation, the insulation rod cover is positioned in the exhaust cylinder and the exhaust of the hot gas from the puffer shaft is suppressed to increase the pressure of an extinguishing gas to be sprayed onto the arc. In a last half of the circuit-breaking operation, the insulation rod cover is positioned in a guard cylinder to promote the exhaust of the hot gas from the puffer shaft as well as to suppress the flow of the hot gas into the insulation cylinder.

Abstract: A puffer-type gas circuit-breaker having improved interruption performance and dielectric performance, comprising: a partition wall provided in a stationary cylinder on the moving side of the circuit-breaker to form an intra-stationary cylinder space, a mechanical puffer chamber provided adjacent to one flange of the partition wall and a hot gas exhaust chamber provided on the same side as another flange of the partition wall, wherein the stationary cylinder has gas inlet holes communicated with the intra-stationary cylinder space and formed on one side relative to a virtual plane that bisects the stationary cylinder in a radial direction, gas outlet holes communicated with the intra-stationary cylinder space, and hot gas exhaust openings communicated with the hot gas exhaust chamber, further communicated with the puffer shaft flow hole after an arc is generated and formed in radial directions of the stationary cylinder and on the other side relative to the virtual plane.

Abstract: In a gas circuit breaker with a parallel capacitor, an interrupting unit is provided inside a sealed vessel filled with an insulating gas; the interrupting unit includes fixed and movable parts. A high-voltage conductor is coupled to the movable part, and an interrupting-unit side insulating rod for moving the movable part is linked with a mover as part of an electric actuator inside an operation device case. A capacitor is electrically coupled to the interrupting unit in parallel inside the sealed vessel. A movable contact is electrically coupled to the capacitor, and the movable contact is linked with a capacitor-side insulating rod. The interrupting-unit side insulating rod or mover has an engaging part inside the case, the capacitor-side insulating rod has a retaining part located on a side of the engaging part, and the retaining part is linked with the sealed vessel by use of a closing-spring.

Abstract: 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.

Abstract: This puffer type gas circuit breaker has: a stationary-side main contact 2 and a movable-side main contact 3, which are provided on the same axis inside a vessel 1 filled with an insulating gas; a stationary-side arcing contact 4; a movable-side arcing contact 5; a puffer cylinder 6; a puffer shaft 7 having a puffer chamber-side exhaust hole 7a and an operation rod-side exhaust hole 7b; a pressure-activated valve 15 for closing the operation rod-side exhaust hole 7b; a puffer piston 9; a flow control section 11 having an opening part 11a; and an insulating nozzle 12. When the interruption operation is completed, a predetermined space is formed inside a puffer chamber 10, the puffer chamber-side exhaust hole 7a and the opening part 11a are connected together, and the operation rod-side exhaust hole 7b is closed by the pressure-activated valve 15.

Abstract: A gas circuit breaker includes a circuit-breaking portion provided within a tank. The tank is filled with insulating gas and disposed in an upright position. The circuit-breaking portion is connected to a bus through a main circuit conductor. The circuit-breaking portion has an operation unit disposed outside the tank. The operation unit is an electric linear motor operation unit composed of a driving portion and a driving energy storage portion. The driving portion is adjacent to the tank. The driving energy storage portion is separated from the driving portion. The driving energy storage portion and the driving portion are electrically connected.

Abstract: In a gas circuit breaker with a parallel capacitor, an interrupting unit is provided inside a sealed vessel filled with an insulating gas; the interrupting unit includes fixed and movable parts. A high-voltage conductor is coupled to the movable part, and an interrupting-unit side insulating rod for moving the movable part is linked with a mover as part of an electric actuator inside an operation device case. A capacitor is electrically coupled to the interrupting unit in parallel inside the sealed vessel. A movable contact is electrically coupled to the capacitor, and the movable contact is linked with a capacitor-side insulating rod. The interrupting-unit side insulating rod or mover has an engaging part inside the case, the capacitor-side insulating rod has a retaining part located on a side of the engaging part, and the retaining part is linked with the sealed vessel by use of a closing-spring.

Abstract: A three-phase circuit-breaker includes: three circuit-breaking portion tanks that each have a circuit-breaking portion therein and are filled with insulating gas; an operation unit that opens and closes the circuit-breaking portion; and a driving mechanism that transmits driving force of the operation unit to the circuit-breaking portion. The operation unit is composed of a drive motor and a control power unit that outputs an opening/closing command to the drive motor. The drive motor is provided in the vicinity of the driving mechanism. The control power unit is disposed at a place different from the drive motor. The drive motor and the control power unit are electrically connected.

Abstract: A dielectric gas produced at the time of current interruption is exhausted into an exhaust structure 1 through an opening 8 formed on a fixed-side support member 6 combined with a fixed arcing contact 4. The exhaust structure 1 has an enlarged portion with a gas flow cross section formed at least before a position at 1/2 of the overall length of the exhaust structure 1 that is uniformly enlarged toward the rear of the exhaust structure 1 with respect to the joint between the exhaust tube 1 and the fixed-side support member 6. As a result, the gas is immediately exhausted into the exhaust structure 1 and the interelectrode insulation recovery performance is ensured.

Abstract: A puffer type gas breaker is provided, in which high-temperature gas, heated by an electric arc produced immediately after a large current is broken, is quickly discharged to enhance inter-pole dielectric performance. A fixing portion for fixing an arc contact is provided in a cylindrical exhaust pipe for exhausting the high-temperature gas heated by an electric arc produced between poles immediately after a large current is broken. A rectifying member or members is provided in the fixing portion of the cylindrical exhaust pipe. An exhaust port or ports is formed in the fixing portion of the cylindrical exhaust pipe, and a shield is disposed around the outer periphery of the exhaust port or ports.

Abstract: A transformer station includes a plurality of power transmission lines receiving electric power, a bus bar connected to the power transmission lines, a transformer connected to the bus bar to transform voltage of the electric power supplied from the bus bar, and breakers between one of the power transmission lines and the bus bar and between the transformer and the bus bar. The breakers are aligned along an imaginary line extending substantially parallel to the bus bar.

Abstract: A circuit breaker with parallel resistor which can satisfy contradictory requirements to induce a preliminary discharge at the time of closing action and to maintain a high interelectrode insulation at the time of interrupting action has been provided in a simple and compact size. The circuit breaker of the invention includes movable unit 41 and stationary unit 31 both on the side of main contact S1, and movable unit 21 and stationary unit 11 both on the side of resistance closing contact S2, wherein the movable unit 21 on the side of the resistance closing contact S1 comprises shield 23 which is adapted either to move lagging behind the movement of movable electrode 22 or to open at its front side during closing action of the circuit breaker such that a preliminary discharge is readily generated between the movable electrode 22 and the stationary electrode 23 in precedence to the main contact.

Abstract: A first puffer chamber is formed by a puffer cylinder having a substantially cylindrical flange portion and a shaft portion, and a fixedly disposed piston. The piston is formed in a cylindrical shape sealed with respect to an external space, and is constituted to be accommodated in the flange portion of the puffer cylinder at the circuit breaking position of the circuit breaking unit. The internal space of the piston is constituted as a second puffer chamber which is designed to communicate with the first puffer chamber. The gas accumulated in the second puffer chamber is continuously blown out toward between the electrodes, thereby prolonging an effective interruptable arc time span without increasing the size of the circuit interrupting unit and operating unit.

Abstract: A switching mechanism for use e.g. in a circuit breaker of an underground electric substation has a movable rod which causes opening and closing of an electrical contact and a hydraulic operating system. The hydraulic operating system uses a hydraulic fluid which has a high flammability temperature or is incombustible. Thus, even if such fluid leaks from the hydraulic operating system, the risk of fire or explosion is minimized. The hydraulic operating system may have a sealed tank for the fluid, preferably with a variable volume expansion chamber. In a further development, the hydraulic operating system and possibly parts of the movable rod, is enclosed in a casing which is sealed and is filled with a gas which does not support combustion therein. Thus, the risk of fire or explosion is further reduced. The casing may have a variable volume expansion chamber.

Abstract: A gas blast circuit breaker comprises an insulation nozzle for blowing extinguishing gas to an arc generated between a stationary contact and a movable contact. The nozzle has a throat section into and out of which one of the two contacts is movable and a divergent section provided downstream of the throat section. A slanting surface for increasing a reflectivity of energy intensity of the arc is formed on the divergent section of the nozzle. The nozzle is formed of a fluoroplastic material and boron nitride powder of not more than 15 vol. % is added as a filler.

Abstract: A puffer type gas circuit breaker includes arc extinguishing gas filled in the interior of the gas circuit breaker, fixed contact, a movable contact disposed in an opposed relationship with respect to the fixed contact so as to come into contact therewith, a fixed piston and a drive shaft slidably extends through the fixed piston, and drives the movable contact toward and away from the fixed contact. A puffer cylinder is slidably fitted on the fixed piston, with the puffer cylinder cooperating with the fixed piston to define a puffer chamber, within the puffer cylinder. An outer cylinder is mounted on an outer periphery of the puffer cylinder to form a thermal puffer chamber outside the puffer cylinder. A cover covers an outer surface of the movable contact, with a first insulating nozzle surrounding the cover to form a first gas flow passage for guiding the arc extinguishing gas from the puffer chamber to an arc generating portion.

Abstract: A gas circuit breaker comprising a pair of contactors separable from each other, an insulating nozzle surrounding the contact portions of the contactors so as to guide a flow of gas, and a puffer chamber for compressing the gas in conjunction with a separating operation of the contact portions so as to supply the gas, guided by the insulating nozzle from the puffer chamber through exhaust passage passing through a hollow portion of the movable one of the contactors located within the insulating nozzle. The exhaust passages are formed between the puffer chamber and one of the contactors.

Abstract: An interrupter including a gas pressurizer for pressurizing a gas to flow toward a forward end of at least one contact of the interrupter, and a first orifice forming a first space with the forward end of the at least one contact for passing the gas pressurized by the gas pressurizer when a flow of electric current is interrupted. A second orifice forms a second space with the at least one contact for passing the gas which passed through the first orifice, with a chamber being formed between the first and second orifices. The chamber has an inner diameter greater than an inner diameter of the first and second orifices. At least one pressurized gas passage is provided through which a portion of the pressurized gas is supplied to the chamber without passing the first orifice so that the pressurized gas supplied to the chamber through the pressurized gas passage flows to the first space formed by the forward end of the at least one contact and the first orifice.

Abstract: A gas circuit breaker comprising: a pair of contactors having separable contact portions, a nozzle arranged to surround the contact portions of the contactors so as to guide a flow of a gas; a puffer chamber for compressing the gas in response to a circuit breaking action and for supplying the compressed gas into the nozzle; and an exhaust passage in one of the contactors which is adjacent to the nozzle, the gas supplied from the puffer chamber being discharged through the exhaust passage. The exhaust passage includes a first passage formed in the one of the contactors so as to extend in the axial direction thereof and second passages communicating with and branching from the first passage and extending radially with respect to the axis of the one of the contactors at positions between gas discharging holes which are provided in the puffer chamber at a predetermined circumferential spacing.