Abstract: To provide a gas circuit breaker designed to achieve further improvement in interruption performance for a small to medium current. The gas circuit breaker according to the present invention includes: an operation mechanism 1; a heat puffer chamber 19; a machine puffer chamber 32; a release valve 34; a movable main contact 5 and movable arc contact 11; a stationary main contact 6 and stationary arc contact 12; a movable-side leading conductor 14; and a stationary-side leading conductor 15, and features: a separation cylinder 21 for radially partitioning the heat puffer chamber 19; an inner circumferential flow path 24 formed on an inner circumferential side of the separation cylinder 21; and a check valve 22 for opening or closing a communication hole 23.

Abstract: There is provided a gas circuit breaker that includes: a puffer shaft connected to one of a pair of arcing contacts, a puffer cylinder that is coaxially provided on an outer circumference of the puffer shaft, an insulating nozzle that is fixed to the puffer cylinder on a breaker side, an insulating rod that connects the puffer shaft and an operating device to each other, a shaft guide that is provided on an outer circumference of the puffer shaft and the insulating rod, and an exhaust guide that is provided on an outer circumference of the shaft guide, in which hot gas is discharged into a gas tank through a shaft exhaust hole of the puffer shaft, between the puffer shaft and the shaft guide, and a conductor exhaust hole of a movable side exhaust conductor in the middle of interrupting operation, the shaft exhaust hole of the puffer shaft communicates with a shaft guide exhaust hole of the shaft guide in a region near a current zero point before the termination of the interrupting operation, and thus an exhau

Abstract: Realized is a shape of a grooved cam that maximizes break performance by appropriately setting an electrode operation, with a minimum weight increase.

Abstract: A symptom of malfunction regarding operating characteristics of a switch should be detected exactly. A switch operating characteristic monitoring device is comprised of a current sensor that measures a close command current of a switch, an auxiliary switch that outputs signals from at least two or more auxiliary contacts with reference to positions of a contactor, a measurement unit that measures signals from the current sensor and the auxiliary switch, a diagnosis unit that judges whether or not a malfunction occurs, and a display unit that displays a malfunction when a malfunction has been determined. A threshold is obtained in advance from multiple results of an opening/closing test performed beforehand. A calculation is made for characteristic times which are obtained from the close command current and signals from the auxiliary switch during actual operation of a circuit breaker. If a deviation is found by comparison with a threshold, a malfunction is determined.

Abstract: Provided is a lubricant for a gas insulated switchgear, with which properties of a base oil such as heat resistance, evaporation loss, fluidity under a low temperature, and chemical stability (oxidation resistance and HF resistance) are balanced at a level higher than the conventional level, and long service life and high reliability of the gas insulated switchgear are achieved. A lubricant for a gas insulated switchgear according to the present invention, contains: a base oil containing a polyalphaolefin having a kinematic viscosity at 40° C. of 50 mm2/s or more; and a thickener containing bisamides.

Abstract: 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.

Abstract: 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.

Abstract: The invention provides a switchgear that is capable of increasing a degree of freedom of a position of a moving arcing contact in a circuit breaker, does not require dimension management of components and a mechanism for adjusting a position of the moving arcing contact, and is capable of simplifying fabrication of components and assembly of devices and reducing cost.

Abstract: 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.

Abstract: 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.

Abstract: A gas leak detection device includes a learning section, which has a correlation between a gas temperature inside gas pressure containers and a surface temperature of the gas pressure containers in a learning period corresponding to a current value flowing in the conductor, to make database, and a diagnosis section, which extracts a gas temperature corresponding to the measured current value and the surface temperature from the learning section in a diagnosis period, corrects a gas pressure value corresponding to an arbitrary surface temperature to a gas pressure value of a reference temperature using the extracted gas temperature, and detects a leak of the insulating gas based on the corrected gas pressure value.

Abstract: A gas circuit breaker is configured by comprising a tank filled with arc extinguishing gas, a pair of fixed side arc contact and moving side arc contact in the tank, a puffer chamber formed with a puffer cylinder including the moving side arc contact at its end and a fixed piston, and an insulating nozzle, attached to the end of the puffer cylinder, surrounding the moving side arc contact, that forms a flow channel to guide arc extinguishing gas from the puffer chamber to the contacts. A puffer cylinder 104 has a cylindrical member 104a at a breaker side end, an end of the insulating nozzle 101 is provided in the cylindrical member 104a. And the gas circuit breaker is configured by further comprising a hollow moving side main contact 102 at a breaker side end of the cylindrical member 104a, a pressing metal fitting 103 to engage an insulating nozzle 101 in the hollow part of the moving side main contact 102.

Abstract: The invention provides a switchgear that is capable of increasing a degree of freedom of a position of a moving arcing contact in a circuit breaker, does not require dimension management of components and a mechanism for adjusting a position of the moving arcing contact, and is capable of simplifying fabrication of components and assembly of devices and reducing cost.

Abstract: A circuit breaker (33) formed with a sealed tank (4) having a breaker section and an operating mechanism (2) is laterally arranged in a lengthwise direction and is fixed to a frame (1), and above the circuit breaker, main bus containers (11, 12) are provided, substantially orthogonally to an axial direction of the circuit breaker (33). Operating mechanism-side working space (B) and breaker section-side working space (C) are provided respectively above the operating mechanism (2) and the sealed tank (4), and a hand hole (5) is provided on an upper surface of the sealed tank (4). A connecting pin (24) is provided in a link mechanism connecting the operating mechanism (2) and the movable contact (7), and an operating mechanism-side working hole for accessibility to the connecting pin (24) from the operating mechanism-side working space (B) is provided.

Abstract: 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.

Abstract: A pair of arcing contacts 3 and 5 facing each other are placed in a tank 1 to perform opening and closing operation, and a puffer cylinder 7 is coaxially provided on the circumference of one arcing contact 5. A puffer chamber 9 is comprised of the puffer cylinder 7, a fixed piston 6, and a hollow rod 8. An insulating nozzle 4 forming a space communicating with the puffer chamber 9 is provided. An exhaust tube 2 for exhausting and cooling hot gas discharged from an arc produced in the insulating nozzle 4 is provided on the circumference of the other arcing contact 3. A structure 11 for temporarily reducing the flow path area is provided on the inner circumferential surface at short of the end portion of the exhaust tube 2.

Abstract: A gas circuit breaker is configured by comprising a tank filled with arc extinguishing gas, a pair of fixed side arc contact and moving side arc contact in the tank, a puffer chamber formed with a puffer cylinder including the moving side arc contact at its end and a fixed piston, and an insulating nozzle, attached to the end of the puffer cylinder, surrounding the moving side arc contact, that forms a flow channel to guide arc extinguishing gas from the puffer chamber to the contacts. A puffer cylinder 104 has a cylindrical member 104a at a breaker side end, an end of the insulating nozzle 101 is provided in the cylindrical member 104a. And the gas circuit breaker is configured by further comprising a hollow moving side main contact 102 at a breaker side end of the cylindrical member 104a, a pressing metal fitting 103 to engage an insulating nozzle 101 in the hollow part of the moving side main contact 102.

Abstract: A circuit breaker (33) formed with a sealed tank (4) having a breaker section and an operating mechanism (2) is laterally arranged in a lengthwise direction and is fixed to a frame (1), and above the circuit breaker, main bus containers (11, 12) are provided, substantially orthogonally to an axial direction of the circuit breaker (33). Operating mechanism-side working space (B) and breaker section-side working space (C) are provided respectively above the operating mechanism (2) and the sealed tank (4), and a hand hole (5) is provided on an upper surface of the sealed tank (4). A connecting pin (24) is provided in a link mechanism connecting the operating mechanism (2) and the movable contact (7), and an operating mechanism-side working hole for accessibility to the connecting pin (24) from the operating mechanism-side working space (B) is provided.

Abstract: A pair of arcing contacts 3 and 5 facing each other are placed in a tank 1 to perform opening and closing operation, and a puffer cylinder 7 is coaxially provided on the circumference of one arcing contact 5. A puffer chamber 9 is comprised of the puffer cylinder 7, a fixed piston 6, and a hollow rod 8. An insulating nozzle 4 forming a space communicating with the puffer chamber 9 is provided. An exhaust tube 2 for exhausting and cooling hot gas discharged from an arc produced in the insulating nozzle 4 is provided on the circumference of the other arcing contact 3. A structure 11 for temporarily reducing the flow path area is provided on the inner circumferential surface at short of the end portion of the exhaust tube 2.

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.