Abstract: A vehicle includes: an engine; a first electric motor capable of inputting or outputting power; a power split mechanism including a sun gear, a ring gear and a planetary carrier rotatably revolvably supporting pinion gears meshing with the sun and ring gears. The planetary carrier, the sun gear and the ring gear are respectively coupled to an engine output shaft, a first electric motor rotary shaft and a drive wheel. The vehicle further includes a second electric motor capable of inputting or outputting power to or from the drive wheel; and a control device setting an engine operation range determined by a limit value of a rotation speed of the pinion gears. To increase durability of the pinion gears the limit value is higher at a high engine rotation and low vehicle speed side than at a low engine rotation and high vehicle speed side. Engine operation is controlled on the basis of the set engine operation range.

Abstract: A vehicle includes: an engine; a first electric motor capable of inputting or outputting power; a power split mechanism including a sun gear, a ring gear and a planetary carrier rotatably revolvably supporting pinion gears meshing with the sun and ring gears. The planetary carrier, the sun gear and the ring gear are respectively coupled to an engine output shaft, a first electric motor rotary shaft and a drive wheel. The vehicle further includes a second electric motor capable of inputting or outputting power to or from the drive wheel; and a control device setting an engine operation range determined by a limit value of a rotation speed of the pinion gears. To increase durability of the pinion gears the limit value is higher at a high engine rotation and low vehicle speed side than at a low engine rotation and high vehicle speed side. Engine operation is controlled on the basis of the set engine operation range.

Abstract: A bi-directional clutch comprises an outer ring, an inner ring and a roller. The roller is retained by a retainer and is positioned between the outer ring and the inner ring. The outer ring has a cam surface, so that the roller forms a wedge that contacts the outer ring and the inner ring.

Abstract: A bi-directional clutch comprises an outer ring, an inner ring and a roller. The roller is retained by a retainer and is positioned between the outer ring and the inner ring. The outer ring has a cam surface, so that the roller forms a wedge that contacts the outer ring and the inner ring.

Abstract: A two-way differential clutch is provided which can prevent the resilient ring for biasing a friction plate from expanding radially outwardly and getting out of the mounting position due to centrifugal force during high-speed rotation. Two retainers having different diameters are mounted between a rotary shaft and an input gear. The large-diameter retainer is fixed to the input gear. Sprags are mounted in pockets formed in the large-diameter retainer and the small-diameter retainer. A flange and a ring groove are formed at one end of the small-diameter retainer. A friction plate arranged on one side of the flange is pressed against the flange by a resilient ring mounted in the ring groove. A restricting portion for restricting the amount of radial expansion of the resilient ring is formed on the friction plate to prevent the resilient ring from radially expanding too much due to centrifugal force during high-speed rotation.

Abstract: In a bidirectional differential clutch in which a rotation of the input gear is transmitted to the rotational shaft through the sprags only when the input gear rotates faster than the rotational shaft, a play in a rotational direction is provided between the rotational shaft and an output gear. With this structure, even when the rotational direction of the input gear is switched from the normal direction to the reverse direction, the sprags can excellently incline so that the bidirectional differential clutch can be rotated in the reverse direction.

Abstract: A two-way differential clutch having sprags. It includes a mechanism that permits the sprags to be inclined instantly in the opposite direction when the rotating direction of an input gear changes over. Two cages having different diameters are mounted between the cylindrical inner surface of an input gear and the cylindrical outer surface of a rotary shaft. The large-diameter cage is fixed to the input gear while the small-diameter cage is rotatably mounted on the rotary shaft. Sprags are received in pockets formed in both cages. A friction plate is rotatably mounted on the small-diameter cage near its end. It is pressed by a resilient member against a flange of the small-diameter cage. The friction plate is nonrotatably coupled to a gear case through a rotation stopper. With this arrangement, it is possible to create a large rotating speed difference between the large-diameter cage and the small-diameter cage when the rotating direction of the input gear changes over.