Abstract: The present invention relates to a 3-position rotational actuator which obtains three stable points by two pairs of field poles, in which the magnetic flux to a rotor due to one pair of field poles of a stator for maintaining the rotor at the first stable point is substantially equal to the magnetic flux to the rotor due to the other pair of field poles of the stator for rotating the rotor from the first stable point. The magnetic flux density of the other pair of field poles of the stator applied to the rotor is set to be smaller than the magnetic flux density of the one pair of field poles of the stator. Therefore, the detention torque can be maintained to the same degree and the drive torque can be improved.

Abstract: An accumulator has a piston axially slidably disposed in a cylinder mounted in a casing, the cylinder and the piston jointly defining a reservoir communicating with an inlet/outlet port in the casing. A piston rod axially movably disposed in the casing has an end slidably fitted in the cylindrical hole of the piston. The piston rod is normally urged by a spring to force the piston into the reservoir. The accumulator also includes a switch mechanism for detecting the position of the piston in the cylinder. The switch mechanism may comprise a reed switch, a light-sensitive switch, a pressure-sensitive switch, or a pushbutton switch.

Abstract: A torque transmission system has driving and driven pulley units around which an endless V-belt extends. Each pulley unit has a stationary pulley part rotatable with a shaft and a movable pulley part disposed to define with the stationary pulley part a circumferentially continuous groove for receiving the V-belt. The movable pulley parts of the pulley units are axially resiliently biased so that the radii of the circle along which the V-belt engages the driving and driven pulley units are varied to change the speed-change ratio of the transmission system. The movable pulley part of the driven pulley unit is axially shifted by the action of fly weights held between a stationary plate fixed to the shaft and a holder fixed to the movable pulley part.

Abstract: In combination with a belt tensioner which includes an idler pulley to be radially displaced under control of an actuator for applying an tensioning force on an endless belt of the drive system for the vehicle accessories, an electric control apparatus comprises a microcomputer for calculating the actual tensioning force on the belt related to radial displacement of the idler pulley and for calculating drive power necessary for driving the vehicle accessories to calculate total drive torque of the vehicle accessories in relation to rotational speed of a prime mover of the vehicle. The microcomputer also calculates an optimum tensioning force based on a desired relationship between the optimum tensioning force and the total drive torque in consideration with the maximum efficiency of power transmission of the belt such that it generates a control signal when the calculated actual tensioning force is different from the calculated optimum tensioning force.

Abstract: A torque transmission belt means comprises a metallic ring which extends around a driving pulley and a driven pulley and a plurality of blocks made of hard material, which are linked up by the ring so as to be shiftably engaged therewith. Each block is provided with a concave portion in the front surface or the rear surface in the moving direction of the ring and an elastic member is fixed to the front surface or the rear surface of a back plate portion of each block, which forms a bottom of the concave portion so that each elastic member is contacted with the back plate portion of the adjacent block. Since each block is contacted with the adjacent blocks through the elastic members, the torque transmission belt means silently operates.

Abstract: A torque transmission belt means comprises a ring having excellent bending and tensile strength which is extended around pulleys positioned in the driving side and the driven side and a series of blocks composed of main blocks made of non-compressive material having high strength and secondary blocks made of elastic material, which are alternately arranged along the ring so as to be shiftably engaged therewith.

Abstract: A torque transmission system has driving and driven pulley units around which an endless V-belt extends. Each pulley unit has a stationary pulley part rotatable with a shaft and a movable pulley part disposed to define with the stationary pulley part a circumferentially continuous groove for receiving the V-belt. The movable pulley parts of the pulley units are axially resiliently biased so that the radii of the circle along which the V-belt engages the driving and driven pulley units are varied to change the speed-change ratio of the transmission system. The movable pulley part of the driven pulley unit is axially shifted by the action of fly weights held between a stationary plate fixed to the shaft and a holder fixed to the movable pulley part.

Abstract: A torque transmission system has driving and driven pulley units drivingly connected by an endless V-belt. Each of the driving and driven pulley units includes a stationary pulley rotatable with a shaft and a movable pulley disposed to define with the stationary pulley a circumferential continuous groove for receiving the V-belt. The movable pulleys of the driving and driven pulley units are axially resiliently biased so that the radii of the circles along which the V-belt engages the driving and driven pulley units are varied to change the speed-change ratio of the transmission system. The movable pulley of the driven pulley unit is axially shifted by fly weights. The driving and driven pulley units are provided with cam mechanisms each comprising a cam member and a follower member. When the load on the driven pulley unit is suddenly varied, the cam mechanisms are operative to keep constant the rotational speed of the driven pulley unit irrespective of variations in the load on the driven pulley unit.

Abstract: A pressurized fluid-operated power transmission device, is typically shown being shaft driven from an automotive engine as the drive for the compressor of a cooler and a fan is provided with a centrifugal governor and valving for limiting output rotational speed of the power transmission device. In one embodiment a noise-preventing back-flow check valve is provided.

Abstract: A torque transmission belt means which is extended between a driving pulley and a driven pulley for transmitting a driving force from the driving pulley to the driven pulley.The torque transmission belt means comprises a plurality of ring-shaped metallic strips which are superimposed on each other, and two kinds of blocks which are arranged along the metallic strips so as to be shiftably engaged therewith.Only one kind of blocks are contacted with said pulleys and the other kind of blocks are bevelled on opposed surfaces facing to the direction of the movement so that they can tilt with respect to one kind of blocks when they are entrained around the pulleys.