Abstract: A nut includes a circulation passage such that balls are circulated through the circulation passage from a first axial end part of rolling raceway to a second axial end part of the rolling raceway. The nut includes a nut body, and end members connected to the opposite axial ends of the nut body. The nut body includes a first member and a second member. The first member includes a second spiral groove on the inner periphery of the first member and a passage having a groove shape opened radially outwardly, the passage being formed on the outer periphery of the first member such that the passage constitutes part of the circulation passage. The second member is placed radially outwardly from the first member and closes the passage from its radially outer side.

Abstract: An actuator includes a motor, a first gear coupled to the motor, a second gear that meshes with the first gear, and a clutch. The clutch includes an outer ring and an inner ring. A plurality of wedge spaces are formed along a circumferential direction between an inner peripheral surface portion of the outer ring and an outer peripheral surface portion of the inner ring. The clutch further includes rolling elements provided in the wedge spaces. While a radial load is not applied to the outer ring, each rolling element does not engage with the outer peripheral surface portion or the inner peripheral surface portion, so that a clearance is generated. While the radial load is applied to the outer ring, each rolling element engages with the outer peripheral surface portion and the inner peripheral surface portion without the clearance.

Abstract: A one-way clutch includes an inner ring, an outer ring, a plurality of rollers, an annular cage that holds the rollers, and springs that bias the rollers toward a first side in a circumferential direction. The inner ring has a rib portion located on a first side in an axial direction and protruding outward in a radial direction. The cage has a pair of annular portions provided on the first side and a second side in the axial direction with respect to the rollers and a plurality of cage bars. One of the annular portions on the first side in the axial direction has an abutting contact surface that comes into abutting contact with the rib portion in the axial direction.

Abstract: A clutch device includes a shaft member, an outer rotor provided on a radially outer side of the shaft member, a clutch module configured to selectively switch between a free state where the shaft member and the outer rotor are allowed to rotate relatively and a lock state where the shaft member and the outer rotor are not allowed to rotate relatively, a coil spring configured to absorb a rotational fluctuation between the shaft member and the outer rotor in the lock state, and a bearing configured to support the shaft member and the outer rotor to rotate relatively is in the free state, and the clutch module is provided on the radially outer side of the shaft member, and the coil spring configured to absorb the rotational fluctuation is provided further radially outwards than the clutch module.

Abstract: An actuator includes a motor, a first gear coupled to the motor, a second gear that meshes with the first gear, and a clutch. The clutch includes an outer ring and an inner ring. A plurality of wedge spaces are formed along a circumferential direction between an inner peripheral surface portion of the outer ring and an outer peripheral surface portion of the inner ring. The clutch further includes rolling elements provided in the wedge spaces. While a radial load is not applied to the outer ring, each rolling element does not engage with the outer peripheral surface portion or the inner peripheral surface portion, so that a clearance is generated. While the radial load is applied to the outer ring, each rolling element engages with the outer peripheral surface portion and the inner peripheral surface portion without the clearance.

Abstract: Displacement of a switching member in a first direction causes rolling elements of each pair to come out of engagement with an outer peripheral portion or an inner peripheral portion and form clearances therewith, resulting in an OFF state of a driving force transmission apparatus. Displacement of the switching member in a second direction causes a downstream one of the rolling elements of each pair in the direction of rotation to come into zero clearance engagement with the outer peripheral portion and the inner peripheral portion, with a clearance formed between an upstream one of the rolling elements of each pair and the outer peripheral portion or the inner peripheral portion, resulting in an ON state of the driving force transmission apparatus.

Abstract: A one-way clutch includes an inner ring, an outer ring, a plurality of rollers, an annular cage that holds the rollers, and springs that bias the rollers toward a first side in a circumferential direction. The inner ring has a rib portion located on a first side in an axial direction and protruding outward in a radial direction. The cage has a pair of annular portions provided on the first side and a second side in the axial direction with respect to the rollers and a plurality of cage bars. One of the annular portions on the first side in the axial direction has an abutting contact surface that comes into abutting contact with the rib portion in the axial direction.

Abstract: Displacement of a switching member in a first direction causes rolling elements of each pair to come out of engagement with an outer peripheral portion or an inner peripheral portion and form clearances therewith, resulting in an OFF state of a driving force transmission apparatus. Displacement of the switching member in a second direction causes a downstream one of the rolling elements of each pair in the direction of rotation to come into zero clearance engagement with the outer peripheral portion and the inner peripheral portion, with a clearance formed between an upstream one of the rolling elements of each pair and the outer peripheral portion or the inner peripheral portion, resulting in an ON state of the driving force transmission apparatus.

Abstract: A driving force transmission device includes an inner ring; an outer ring; a roller pair constituted by a first roller and a second roller; an elastic member; a first cage including a first pressing portion; a second cage including a second pressing portion; a first guide member; a second guide member; and an electromagnetic clutch including an armature connected to the first and second guide members. Along with rotation of the first cage toward the circumferential second side, the first pressing portion presses the first roller toward the circumferential second side. Along with rotation of the second cage toward the circumferential first side, the second pressing portion presses the second roller toward the circumferential first side.

Abstract: An ECU acquires a steering torque detected by a torque sensor (step S1). The ECU drives an electromagnet of a solenoid actuator (step S2). The ECU drives a steering operation motor in accordance with the direction of the detected steering torque acquired in step S1 to apply, to an output shaft of a clutch, a torque acting in such a direction that a torque being exerted on a clutch mechanism is reduced (step S3). When a predetermined time has elapsed since driving of the steering operation motor in step S3 (step S4: YES), the ECU 40 reverses a driving direction of the steering operation motor to apply, to the output shaft of the clutch, a torque acting in a direction opposite to the direction of the last torque applied (step S5).

Abstract: A driving force transmission device includes: a clutch unit that connects and disconnects input and output shafts to and from each other; an annular electromagnet disposed so that it can rotate relative to a shaft body portion included in the input shaft; a rotor that faces one side in the axial direction of the electromagnet; an armature that faces one side in the axial direction of the rotor, that is disposed so that it can move in the axial direction, and that moves in the axial direction to engage and disengage the clutch unit; an internally threaded portion that is formed on the inner periphery of the rotor and engages with an externally threaded portion formed on the outer periphery of the shaft body portion; and a second elastic member that elastically presses the rotor screw-fitted on the outer periphery of the shaft body portion toward the electromagnet.

Abstract: An ECU acquires a steering torque detected by a torque sensor (step S1). The ECU drives an electromagnet of a solenoid actuator (step S2). The ECU drives a steering operation motor in accordance with the direction of the detected steering torque acquired in step S1 to apply, to an output shaft of a clutch, a torque acting in such a direction that a torque being exerted on a clutch mechanism is reduced (step S3). When a predetermined time has elapsed since driving of the steering operation motor in step S3 (step S4: YES), the ECU 40 reverses a driving direction of the steering operation motor to apply, to the output shaft of the clutch, a torque acting in a direction opposite to the direction of the last torque applied (step S5).

Abstract: A driving force transmission device includes an inner ring; an outer ring; a roller pair constituted by a first roller and a second roller; an elastic member; a first cage including a first pressing portion; a second cage including a second pressing portion; a first guide member; a second guide member; and an electromagnetic clutch including an armature connected to the first and second guide members. Along with rotation of the first cage toward the circumferential second side, the first pressing portion presses the first roller toward the circumferential second side. Along with rotation of the second cage toward the circumferential first side, the second pressing portion presses the second roller toward the circumferential first side.

Abstract: A rotation adjusting mechanism is provided in a power transmission path from a pulley to a rotation shaft and includes an elastic member and a clutch mechanism. The elastic member reduces a minute change in rotation generated in at least one of the pulley and the rotating shaft by its elastic deformation. The clutch mechanism is provided in an intermediate position of the power transmission path from the elastic member to the rotating shaft and configured to interrupt the power transmission from the pulley to the rotating shaft when a rotation speed of the pulley lowers below a rotation speed of the rotating shaft by a predetermined value or greater.

Abstract: A length of each pocket of a cage in a circumferential direction is smaller than the sum of an outer diameter of a roller and a free length of a coil spring. The cage can rotate relative to an inner ring having cam surfaces in accordance with revolution of the rollers in an overload-applied condition, and the cage can not rotate in a direction opposite to a direction of revolution of the rollers in the overload-applied condition.

Abstract: A rotation adjusting mechanism is provided in a power transmission path from a pulley to a rotation shaft and includes an elastic member and a clutch mechanism. The elastic member reduces a minute change in rotation generated in at least one of the pulley and the rotating shaft by its elastic deformation. The clutch mechanism is provided in an intermediate position of the power transmission path from the elastic member to the rotating shaft and configured to interrupt the power transmission from the pulley to the rotating shaft when a rotation speed of the pulley lowers below a rotation speed of the rotating shaft by a predetermined value or greater.

Abstract: A length of each pocket of a cage in a circumferential direction is smaller than the sum of an outer diameter of a roller and a free length of a coil spring. The cage can rotate relative to an inner ring having cam surfaces in accordance with revolution of the rollers in an overload-applied condition, and the cage can not rotate in a direction opposite to a direction of revolution of the rollers in the overload-applied condition.