A vehicle has an internal combustion engine, an accessory, and a system having first and second belts extending between a drive assembly rotatably connected to a crankshaft of the engine and a driven assembly rotatably connected to a driveshaft of the accessory. One of the drive and driven assemblies comprises a mechanism with a shaft supporting first and second pulleys, with the first and second pulleys associated with the first and second belts, respectively. The first pulley is selectively engaged with the shaft in response to an engine speed being below a threshold value, and the second pulley is selectively engaged with the shaft in response to the engine speed being above the threshold value.

A power transmission device PT includes a clutch input part 120, a clutch output part 130, a start clutch 110 which can connect the clutch input part 120 and the clutch output part 130 to each other, and an electric motor MG having a rotor MGa. The clutch input part 120, the clutch output part 130, and the start clutch 110 are arranged in the rotor MGa. The power transmission device PT includes a switching mechanism 140 which is switchable between an output side correction state in which the rotor MGa and the clutch output part 130 are connected to each other and an input side connection state in which the rotor MGa and the clutch input part 120 are connected to each other.

Overrunning clutch units are disclosed. In one example, the overrunning clutch unit may include inner and outer rings that can be rotated relative to each other. Clamping members may transmit a torque between the two rings in one peripheral direction, the clamping members being arranged between the rings. A first bearing device may be configured to support the two rings, wherein the first bearing device is arranged between the rings at a first axial side of the clamping members. A second bearing device may be configured to support the two rings, wherein the second bearing device is arranged at a second, opposing, axial side of the clamping members so that a tilting of the inner ring relative to the outer ring is prevented.

A one-way clutch includes one or more annular members and one or more annular elastic bodies. The annular member is attached to a side plate of an outer race in the axial outer side of a seal member and includes a facing surface that faces an outer circumferential surface of an inner race with a gap and a recess formed in the facing surface. The annular elastic body is fitted into the outer circumferential surface of the inner surface corresponding to the recess so as to be in close contact therewith.

To provide a cam clutch capable of preventing unwanted jamming of cams and switchable between operation modes with little force, thereby allowing size reduction. The cam clutch includes an inner race, an outer race, a plurality of cams, and a biasing means biasing the plurality of cams. The plurality of cams include first cams and second cams that have different engaging directions. The cam clutch further includes a frictional resistance generating means for generating friction resistance between a component adapted to tilt the first cams or second cams in the engaging direction, and the inner race and/or outer race when the first cams and second cams are simultaneously lifted off and separated from the raceways of the inner race and/or outer race during switching of operation modes.

A clutch includes a rotatable inputting member, a rotatable outputting member, a stationary member, and a contact member. The outputting member includes an output contact portion. The contact member is positioned between the outputting member and the stationary member and includes an arcuate first contact surface and a second contact surface. When the input torque for rotating the inputting member is inputted, the outputting member and the contact member rotate in contact with the inputting member. When a reverse input torque for rotating the outputting member is inputted, the outputting member is spaced from the inputting member, and the output contact portion of the outputting member urges the first contact surface against the stationary member by urging the second contact surface of the contact member thereby to prevent rotation of the outputting member.

A power transmission device PT includes a clutch input part 120, a clutch output part 130, a start clutch 110 which can connect the clutch input part 120 and the clutch output part 130 to each other, and an electric motor MG having a rotor MGa. The clutch input part 120, the clutch output part 130, and the start clutch 110 are arranged in the rotor MGa. The power transmission device PT includes a switching mechanism 140 which is switchable between an output side correction state in which the rotor MGa and the clutch output part 130 are connected to each other and an input side connection state in which the rotor MGa and the clutch input part 120 are connected to each other.

The steering device includes first and second motors for steering which have common electric characteristics; first and second current sensors detecting first and second current values in the first and second motor, respectively; and abnormality diagnosis units. The abnormality diagnosis units make an abnormality diagnosis indicating that the steering device is abnormal when difference between the first and second current values exceeds a predetermined threshold value. When some abnormality occurs in the current detecting units for detecting the magnitudes of a current flowing through the steering motor, an abnormality diagnosis is rapidly made by comparing the difference with the predetermined value.