Abstract: An actuator 1 is disclosed including a stationary member 15, a rotational member 17 disposed for rotating capability with respect to the stationary member 15, a movable member 19 disposed for movements with respect to the rotational member 17, a drive power source 25 rotating the rotational member 17, and a converting mechanism disposed between the rotational member 17 and the movable member 19 to convert rotation of the rotational member to an operating force for an operative unit.

Abstract: An actuator for engagement and disengagement operation of a power transmission device is provided with a first plate being fixed, a second plate being movable in a direction of the engagement and disengagement operation so as to be engaged with the first plate, a third plate disposed opposite to the second plate with respect to the first plate, the third plate being rotatably engaged with the second plate, a drive unit engageable with the third plate so as to rotate the third plate, a cam mechanism converting a rotation of the third plate to a movement of the second plate in the direction of the engagement and disengagement operation and a retaining device restricting a relative rotation range of the third plate with respect to the drive unit. The second plate moved by the cam mechanism drives the power transmission device in the direction of the engagement and disengagement operation so as to intermit a power transmission thereof.

Abstract: An actuator for engagement and disengagement operation of a power transmission device is provided with a first plate being fixed, a second plate being movable in a direction of the engagement and disengagement operation so as to be engaged with the first plate, a third plate disposed opposite to the second plate with respect to the first plate, the third plate being rotatably engaged with the second plate, a drive unit engageable with the third plate so as to rotate the third plate, a cam mechanism converting a rotation of the third plate to a movement of the second plate in the direction of the engagement and disengagement operation and a retaining device restricting a relative rotation range of the third plate with respect to the drive unit. The second plate moved by the cam mechanism drives the power transmission device in the direction of the engagement and disengagement operation so as to intermit a power transmission thereof.

Abstract: An actuator 1 is disclosed including a stationary member 15, a rotational member 17 disposed for rotating capability with respect to the stationary member 15, a movable member 19 disposed for movements with respect to the rotational member 17, a drive power source 25 rotating the rotational member 17, and a converting mechanism disposed between the rotational member 17 and the movable member 19 to convert rotation of the rotational member to an operating force for an operative unit.

Abstract: An electromagnetic wet clutch system includes operation members configured to magnetically work. The system includes a set of clutch plates configured to engage by the operation members. The set of clutch plates includes first plates with first sides. Respective one of the first sides is configured to contact respective one of the operation members. At least one of the first sides is boundary-lubricative.