Abstract: A vacuum-capacitor-type instrument voltage transformer (1) is equipped with a main capacitor (2) and an insulating tube (3) that accommodates the main capacitor (2). A voltage dividing capacitor (4) is connected to the main capacitor (2) in series. The main capacitor (2) is equipped with a plurality of vacuum capacitors (2a) to (2c) that are connected in series. A high-voltage-side electrode (6) is provided on a high-voltage side of the insulating tube (3), and a ground-side electrode (7) is provided on its low-voltage side. The high-voltage-side electrode (6) is equipped with a high-voltage shield (8). Electrostatic capacity of the vacuum capacitor (for example, the vacuum capacitor (2a)) disposed on the high-voltage side is set to be greater than electrostatic capacity of the vacuum capacitor (for example, the vacuum capacitor (2b)) disposed on the low-voltage side.

Abstract: A vacuum-capacitor-type instrument voltage transformer (1) is equipped with a main capacitor (2) and an insulating tube (3) that accommodates the main capacitor (2). A voltage dividing capacitor (4) is connected to the main capacitor (2) in series. The main capacitor (2) is equipped with a plurality of vacuum capacitors (2a) to (2c) that are connected in series. A high-voltage-side electrode (6) is provided on a high-voltage side of the insulating tube (3), and a ground-side electrode (7) is provided on its low-voltage side. The high-voltage-side electrode (6) is equipped with a high-voltage shield (8). Electrostatic capacity of the vacuum capacitor (for example, the vacuum capacitor (2a)) disposed on the high-voltage side is set to be greater than electrostatic capacity of the vacuum capacitor (for example, the vacuum capacitor (2b)) disposed on the low-voltage side.

Abstract: In a vacuum chamber (1), an emitter (3) and a target (7) are opposed to each other. A guard electrode (5) is disposed around an outer circumference of an electron generating portion (31) of the emitter (3). A supporting part (4) supports the emitter (3) movably in an end-to-end direction of the vacuum chamber (1). Reforming treatment is performed on the guard electrode (5) by operating the supporting part (4), moving the emitter (3) to an open end (21) side (non-discharge position) and applying a voltage to repeatedly effect discharge on the guard electrode (5) in a state where field emission from the electron generation portion (31) is suppressed. After the reforming treatment, the supporting part (4) is again operated. The emitter (3) is moved to an open end (22) side (discharge position) and placed in a state where field emission from the electron generation portion (31) is allowed.

Abstract: In a vacuum chamber (1), an emitter (3) and a target (7) are opposed to each other. A guard electrode (5) is disposed around an outer circumference of an electron generating portion (31) of the emitter (3). A supporting part (4) supports the emitter (3) movably in an end-to-end direction of the vacuum chamber (1). Reforming treatment is performed on the guard electrode (5) by operating the supporting part (4), moving the emitter (3) to an open end (21) side (non-discharge position) and applying a voltage to repeatedly effect discharge on the guard electrode (5) in a state where field emission from the electron generation portion (31) is suppressed. After the reforming treatment, the supporting part (4) is again operated. The emitter (3) is moved to an open end (22) side (discharge position) and placed in a state where field emission from the electron generation portion (31) is allowed.

Abstract: [Task] The present invention aims to provide a vacuum capacitor instrument voltage transformer by which current and voltage can be much precisely measured. [Means for achieving task] The means is so made that a main capacitor portion 8 and a voltage dividing capacitor portion 10 are installed in a earthed vacuum vessel, a main ground circuit 30 is provided through which a leak current I2 flows from an outer surface of the primary line-path side vacuum vessel to the earth E, and a voltage dividing ground circuit 31 is provided through which a leak current I11 flows to the earth E through a voltage dividing insulating cylindrical member 11 that is disposed between an earthed portion and each of the main capacitor portion and the voltage dividing capacitor portion.

Abstract: A vacuum capacitor includes a fixed electrode, a movable electrode, a movable electrode shaft, a magnetic flux receiving unit, a magnetic flux generating unit and a capacitance control unit. The fixed electrode is formed from a plurality of electrode members in a vacuum casing. The movable electrode is formed from a plurality of electrode members arranged in gaps formed between the electrode members of the fixed electrode in the vacuum casing. The movable electrode shaft supports the movable electrode. Capacitance appearing between the movable electrode and the fixed electrode is varied by rotation of the movable electrode shaft. The magnetic flux receiving unit rotates the movable electrode shaft in the vacuum casing. The magnetic flux generating unit is located outside the vacuum casing and rotates the magnetic flux receiving unit by magnetic attraction. The capacitance control unit rotates the magnetic flux generating unit.

Abstract: A vacuum capacitor includes a fixed electrode, a movable electrode, a movable electrode shaft, a magnetic flux receiving unit, a magnetic flux generating unit and a capacitance control unit. A plurality of electrode members in a vacuum casing form the fixed electrode. The fixed electrode is divided into a plurality of fixed electrodes, and each fixed electrode is lead outside the vacuum casing and electrically connected to each other in series. A plurality of electrode members arranged in gaps between the electrode members of the fixed electrode form the movable electrode. Rotating the movable electrode shaft, which supports the movable electrode, varies capacitance between the movable electrode and the fixed electrode. The magnetic flux receiving unit rotates the movable electrode shaft. The magnetic flux generating unit, located outside the vacuum casing, rotates the magnetic flux receiving unit by magnetic attraction. The capacitance control unit rotates the magnetic flux generating unit.

Abstract: [Task] The present invention aims to provide a vacuum capacitor instrument voltage transformer by which current and voltage can be much precisely measured. [Means for Achieving Task] The means is so made that a main capacitor portion 8 and a voltage dividing capacitor portion 10 are installed in a earthed vacuum vessel, a main ground circuit 30 is provided through which a leak current I2 flows from an outer surface of the primary line-path side vacuum vessel to the earth E, and a voltage dividing ground circuit 31 is provided through which a leak current I11 flows to the earth E through a voltage dividing insulating cylindrical member 11 that is disposed between an earthed portion and each of the main capacitor portion and the voltage dividing capacitor portion.

Abstract: [Object] An object of the present invention is to provide a vacuum capacitor, a vacuum state of a vacuum chamber of which is maintained without bellows etc., and whose capacitance is easily adjustable, and a decrease of life of which is lessened. [Means to Solve] A fixed electrode 4 is formed by arranging a plurality of flat electrode members 5 in layers at a certain distance in an axial direction of a vacuum chamber 1b in the vacuum chamber 1b.

Abstract: [Object] An object of the present invention is to provide a vacuum capacitor, a vacuum state of a vacuum chamber of which is maintained without bellows etc., and whose capacitance is easily adjustable, and a decrease of life of which is lessened. [Means to solve] A fixed electrode 4 is formed by arranging a plurality of flat electrode members 5 in layers at a certain distance in an axial direction of a vacuum chamber 1b in the vacuum chamber 1b.

Abstract: An attraction coil, a repulsion coil and a plunger are disposed in a magnetic path of an electromagnetic device. An starting flux generating section is disposed between the attraction coil and the repulsion coil in the magnetic path. A magnetic flux of the starting flux generating section is repulsed magnetically by a magnetic flux of the repulsion coil at a part of the magnetic path to start the plunger. The plunger is attracted to one of first and second magnetic path parts by electromagnetic forces generated from magnetic fluxes of the attraction coil and the repulsion coil.

Abstract: A vacuum capacitor includes a vacuum vessel, stationary and movable electrodes arranged in the vacuum vessel, and a bellows which follows the movable electrode to maintain the hermeticity of the inside of the vacuum vessel and which serves as a current path, wherein the bellows is formed of a conduction high-strength heat resisting alloy.

Abstract: A vacuum capacitor includes a vacuum vessel, stationary and movable electrodes arranged in the vacuum vessel, and a bellows which follows the movable electrode to maintain the hermeticity of the inside of the vacuum vessel and which serves as a current path, wherein the bellows is formed of a conduction high-strength heat resisting alloy.

Abstract: An attraction coil, a repulsion coil and a plunger are disposed in a magnetic path of an electromagnetic device. An starting flux generating section is disposed between the attraction coil and the repulsion coil in the magnetic path. A magnetic flux of the starting flux generating section is repulsed magnetically by a magnetic flux of the repulsion coil at a part of the magnetic path to start the plunger. The plunger is attracted to one of first and second magnetic path parts by electromagnetic forces generated from magnetic fluxes of the attraction coil and the repulsion coil.

Abstract: A vacuum switch comprises a first vacuum container containing therein a circuit breaker, a second vacuum container containing therein the first vacuum container and grounded, and a third vacuum container connected to the second vacuum container, containing therein a disconnecting switch and an earth device and grounded. The second and third vacuum containers are isolated in vacuum from the first vacuum container, and the second vacuum container is electrically insulated from the first vacuum container. The second vacuum container contains an insulator fixed to a conductor connected to the circuit breaker and a movable rod partially disposed out of the vacuum containers and operating the circuit breaker to open and close. The disconnecting switch, circuit breaker and the insulator are arranged in a line. A vacuum switchgear comprises the above-mentioned vacuum switches of the number corresponding to three phases and necessary components, each being contained in a metal box.

Abstract: A vacuum exhaust element of a vacuum switch has an ordinary withstand voltage because the vacuum vessel and power source element are grounded, therefore not requiring the high voltage to be taken into consideration. This way, the vacuum exhaust element is miniaturized and it is safe for a worker to touch the vacuum vessel and the vacuum exhaust element when performing maintenance and/or inspection.

Abstract: A vacuum switch comprises a first vacuum container containing therein a circuit breaker, a second vacuum container containing therein the first vacuum container and grounded, and a third vacuum container connected to the second vacuum container, containing therein a disconnecting switch and an earth device and grounded. The second and third vacuum containers are isolated in vacuum from the first vacuum container, and the second vacuum container is electrically insulated from the first vacuum container. The second vacuum container contains an insulator fixed to a conductor connected to the circuit breaker and a movable rod partially disposed out of the vacuum containers and operating the circuit breaker to open and close. The disconnecting switch, circuit breaker and the insulator are arranged in a line. A vacuum switchgear comprises the above-mentioned vacuum switches of the number corresponding to three phases and necessary components, each being contained in a metal box.

Abstract: The invention aims at providing a vacuum circuit-breaker, a vacuum bulb used therein and electrodes for the vacuum bulb, which can reduce the manufacturing cost while being of high performance and compact in size. The invention resides in a vacuum circuit-breaker, a vacuum bulb and electrodes for the vacuum bulb, which are characterized in that fixed and movable electrodes each comprise arc electrodes, whose entire surfaces, mutually facing each other, are made of an alloy containing a refractory metal and a highly conductive metal, and electrode rods of a highly conductive metal supporting the respective arc electrodes, and that each arc electrode and the mating electrode rod are integrally formed by means of solid-phase diffusion bonding.

Abstract: The invention aims at providing a vacuum circuit-breaker, a vacuum valve used therein and electrodes for the vacuum valve, which can reduce the manufacturing cost while being of high performance and compact in size. The invention resides in a vacuum circuit-breaker, a vacuum valve and electrodes for the vacuum valve, which are characterized in that fixed and movable electrodes each comprise arc electrodes, whose entire surfaces, mutually facing each other, are made of an alloy containing a refractory metal and a highly conductive metal, and electrode rods of a highly conductive metal supporting the respective arc electrodes, and that each arc electrode and the mating electrode rod are integrally formed by means of solid-phase diffusion bonding.

Abstract: An object of the present invention is to provide vacuum switch suitable for a distribution and transformation system compatible between structural simplicity and reliability and a vacuum switchgear using the vacuum switch.