Abstract: A gas circuit breaker includes: a fixed arc contact disposed on an axis of motion, whose tip is directed to one side in a first direction that is parallel to the axis of motion; a movable arc contact that can reciprocate along the axis of motion between a position when in contact with the tip of the fixed arc contact and a position when separated from the tip of the fixed arc contact; and a first permanent magnet and a second permanent magnet as a permanent magnet whose magnetic poles are aligned in a second direction that is a direction perpendicular to the first direction. The fixed arc contact has a shape that is gradually widened in a direction away from the axis of motion from the tip toward another side in the first direction.

Abstract: A gas circuit breaker includes: a fixed arc contact disposed on an axis of motion, whose tip is directed to one side in a first direction that is parallel to the axis of motion; a movable arc contact that can reciprocate along the axis of motion between a position when in contact with the tip of the fixed arc contact and a position when separated from the tip of the fixed arc contact; and a first permanent magnet and a second permanent magnet as a permanent magnet whose magnetic poles are aligned in a second direction that is a direction perpendicular to the first direction. The fixed arc contact has a shape that is gradually widened in a direction away from the axis of motion from the tip toward another side in the first direction.

Abstract: 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.

Abstract: 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.

Abstract: Conventional cleaning sheets having brush parts provided on a surface of substratum sheet have been satisfactory in the trapping of dirt or dust at the brush parts but unsatisfactory in the trapping of dirt or dust at areas between brush parts where no brush is present. It is intended to provide a cleaning sheet with which any dirt or dust having sneaked through areas between brush parts and remaining untrapped can be trapped by brush parts provided in alternately positioning relationship adjacent to the brush parts, thereby attaining effective cleaning. The cleaning sheet comprises a sheet substratum and, disposed on at least one major surface thereof, multiple brush part lines each provided with multiple brush parts arranged intermittently along one direction of the sheet substratum, the multiple brush part lines arranged in a direction intersecting with the one direction, and that mutually adjacent brush part lines are provided so that the respective brush parts are alternately positioned.

Abstract: Conventional cleaning sheets having brush parts provided on a surface of substratum sheet have been satisfactory in the trapping of dirt or dust at the brush parts but unsatisfactory in the trapping of dirt or dust at areas between brush parts where no brush is present. It is intended to provide a cleaning sheet with which any dirt or dust having sneaked through areas between brush parts and remaining untrapped can be trapped by brush parts provided in alternately positioning relationship adjacent to the brush parts, thereby attaining effective cleaning. The cleaning sheet comprises a sheet substratum and, disposed on at least one major surface thereof, multiple brush part lines each provided with multiple brush parts arranged intermittently along one direction of the sheet substratum, the multiple brush part lines arranged in a direction intersecting with the one direction, and that mutually adjacent brush part lines are provided so that the respective brush parts are alternately positioned.