Abstract: A speed reducer is configured to reduce a rotational speed of rotation generated by torque received from a drive device and output the torque of the rotation of the reduced rotational speed. A drive cam has a plurality of drive cam grooves formed at one end surface of the drive cam and is rotated by the torque outputted from the speed reducer. A driven cam has a plurality of driven cam grooves formed at one end surface of the driven cam while each of the plurality of rolling elements is clamped between a corresponding one of the plurality of drive cam grooves and a corresponding one of the plurality of driven cam grooves. At least a part of each of the plurality of drive cam grooves overlaps with the speed reducer in the axial direction.

Abstract: A planetary gear has: a first planetary gear annular surface formed at one axial end of the planetary gear and a second planetary gear annular surface formed at another axial end of the planetary gear. A sun gear has a sun gear annular surface that is opposed to the first planetary gear annular surface. A second ring gear has an output-side annular surface that is opposed to the second planetary gear annular surface. A relative movement of a carrier subassembly relative to a housing in an axial direction is limited when the first planetary gear annular surface abuts against the sun gear annular surface or when the second planetary gear annular surface abuts against the output-side annular surface.

Abstract: A normal-time drive cam groove extends from a drive cam specific point, which is defined as a specific point of the drive cam, toward one side in a circumferential direction of the drive cam. A groove bottom at the normal-time drive cam groove is sloped relative to one end surface of the drive cam such that a depth of the groove bottom continuously decreases from the drive cam specific point toward the one side in the circumferential direction of the drive cam. An emergency-time drive cam groove extends from the drive cam specific point toward another side in the circumferential direction of the drive cam.

Abstract: At a drive cam slope groove, a groove bottom is sloped relative to one end surface of a drive cam such that a depth of the groove bottom continuously decreases from one side toward other side in a circumferential direction. At a drive cam planar groove, the groove bottom is parallel to the one end surface of the drive cam. A drive cam connection groove has: one end connected to an end of the drive cam slope groove located on the other side in the circumferential direction of the drive cam; and the other end connected to an end of the drive cam planar groove located on the one side in the circumferential direction. A slope angle of the groove bottom relative to the one end surface of the drive cam continuously changes from the one end to the other end of the drive cam connection groove.

Abstract: A rotational translation unit includes a rotation portion that rotates relative to a housing upon receiving an input of torque output from a speed reducer, and a translation portion that moves relative to the housing in an axial direction according to rotation of the rotation portion relative to the housing. A clutch is provided between a first transmission portion and a second transmission portion that are rotatable relative to the housing, and the clutch allows transmission of the torque between the first transmission portion and the second transmission portion in an engaged state of the clutch, and interrupts the transmission of the torque between the first transmission portion and the second transmission portion in a disengaged state of the clutch. A return spring is capable of urging the rotational translation unit in a direction away from the clutch relative to the housing.

Abstract: Torque of a prime mover is input into a sun gear. A planetary gear revolves in a circumferential direction of the sun gear while rotating and meshing with the sun gear. A carrier has an annular shape, rotatably supports the planetary gear, and is rotatable relative to the sun gear. A first ring gear is fixed to a housing, and meshes with the planetary gear. A second ring gear meshes with the planetary gear, is different from the first ring gear in number of teeth of a tooth portion, and outputs torque to a rotation portion. At least a part of the sun gear in an axial direction is located radially inward of the carrier. At least a part of the first ring gear and at least a part of the second ring gear in the axial direction are located radially outward of the carrier.

Abstract: A prime mover includes a stator fixed to a housing, and a rotor rotatable relative to the stator. The prime mover outputs torque from the rotor by being supplied with electric power. A speed reducer reduces the torque of the prime mover and outputs the reduced torque. The speed reducer includes a sun gear to which the torque from the rotor is input, and a planetary gear that revolves in a circumferential direction of the sun gear while rotating in a state of meshing with the sun gear. The rotor and the sun gear are formed separately, and are disposed coaxially so as to be integrally rotatable.

Abstract: A sun gear of a speed reducer is provided coaxially with and integrally rotatably with a rotor of a prime mover. Multiple planetary gears are disposed in a circumferential direction of the sun gear, and are capable of revolving in the circumferential direction of the sun gear while rotating in a state of meshing with the sun gear. A carrier rotatably supports the planetary gears, and is rotatable relative to the sun gear. A first ring gear is fixed to a housing, and has a first ring gear tooth portion capable of meshing with the planetary gears. A second ring gear is rotatable integrally with a rotation portion, and has a second ring gear tooth portion capable of meshing with the planetary gears. The second ring gear tooth portion is different in number of teeth from the first ring gear tooth portion.

Abstract: A state changing unit is capable of contacting a clutch, and being configured to receive a force along the axial direction from a translation portion and change a state of the clutch to an engaged state or a disengaged state according to a position of the translation portion in an axial direction relative to a housing. A fixed end is non-rotatable relative to the housing. A return spring is disposed on a side of the fixed end opposite to the clutch, and capable of urging the translation portion in a direction away from the clutch with respect to the fixed end.

Abstract: A prime mover includes a stator that is provided in a housing and a rotor that is provided rotatably relative to the stator, and is capable of outputting a torque from the rotor by being supplied with electric power. A bearing portion includes multiple bearing rolling bodies that roll in a circumferential direction of the rotor and rotatably support the rotor, and a lubricant that lubricates a periphery of the bearing rolling bodies. One bearing portion that rotatably supports the rotor is provided. A speed reducer includes an input unit that is provided rotatably integrally with and coaxially with the rotor and that receives the torque from the rotor.

Abstract: A state changing unit is provided radially outward of a translation portion and movable in an axial direction relative to the translation portion. The state changing unit is in contact with or separated from the clutch. The state changing unit receives a force in the axial direction from the translation portion such that the state changing unit is pressed against the clutch. The state changing unit is capable of changing a state of the clutch to an engaged state or a disengaged state according to a position of the translation portion in the axial direction relative to the housing. A movement restriction portion is provided on the translation portion and located between the state changing unit and the clutch. The movement restriction portion contacts the state changing unit and restricts movement of the state changing unit relative to the translation portion toward the clutch.

Abstract: A prime mover includes a stator fixed to a housing, and a rotor rotatable relative to the stator. The prime mover is capable of outputting torque from the rotor by being supplied with electric power. A speed reducer is capable of reducing the torque of the prime mover and outputting the reduced torque. The speed reducer includes a sun gear rotatable integrally with the rotor, and planetary gears capable of revolving in a circumferential direction of the sun gear while rotating in a state of meshing with the sun gear. A gear width of the sun gear is set such that a length in the axial direction by which the sun gear and the planetary gear are overlapped is smaller than a gear width of the planetary gear.

Abstract: A first drive cam groove extends from a drive cam specific position to one side in a circumferential direction. A second drive cam groove extends from the drive cam specific position to the other side in the circumferential direction, and an inclination angle of a groove bottom with respect to one end surface of the drive cam main body is larger than that of the first drive cam groove. A first driven cam groove extends from a driven cam specific position to one side in a circumferential direction. A second driven cam groove extends from the driven cam specific position to the other side in the circumferential direction, and an inclination angle of a groove bottom with respect to one end surface of the driven cam main body is larger than that of the first driven cam groove.

Abstract: A clutch of a clutch device is provided between a first transmission portion and a second transmission portion that are rotatable relative to a housing. A state changing unit is configured to receive a force in an axial direction from a translation portion and change a state of the clutch to an engaged state or a non-engaged state according to a relative position in the axial direction of the translation portion with respect to the housing. An urging member is configured to urge the translation portion in a direction to switch the clutch from the engaged state to the non-engaged state. A retainer member is fixed directly to the housing and is configured to restrict an axial position of the urging member.

Abstract: A housing includes an accommodation space for a prime mover and a speed reducer. A rotational translation unit includes a rotation portion that rotates relative to the housing upon receiving torque outputted from the speed reducer, and a translation portion that moves relative to the housing in an axial direction according to rotation of the rotation portion. The accommodation space is between the rotation portion and the housing. A clutch in a clutch space allows or interrupts transmission of torque between a first transmission portion and a second transmission portion. The rotation portion is between the clutch space and the accommodation space. A sealing member has an annular shape in contact with the rotation portion, and maintains an air-tight or liquid-tight state between the accommodation space and the clutch space.

Abstract: A first drive cam groove extends from a drive cam specific position to one side in a circumferential direction. A second drive cam groove extends from the drive cam specific position to the other side in the circumferential direction, and an inclination angle of a groove bottom with respect to one end surface of the drive cam main body is larger than that of the first drive cam groove. A first driven cam groove extends from a driven cam specific position to one side in a circumferential direction. A second driven cam groove extends from the driven cam specific position to the other side in the circumferential direction, and an inclination angle of a groove bottom with respect to one end surface of the driven cam main body is larger than that of the first driven cam groove.

Abstract: A rotary actuator includes a housing, a motor, a speed reducer, and a rotational translation unit. The motor includes a stator that includes a coil and is fixed to the housing, and a rotor that is provided with a magnet and rotates when the coil is energized. The speed reducer decelerates and outputs a torque of the motor. The speed reducer is a planetary gear mechanism including a sun gear, multiple planetary gears, and a ring gear. At least one of projection region components, which are components constituting the speed reducer and are located in a magnet projection region obtained by projecting a magnet in an axial direction, is formed of a non-magnetic material.

Abstract: A prime mover includes a stator provided in a housing, a rotor provided to be rotatable relative to the stator, and a magnet provided in the rotor, and is operated by energization and capable of outputting a torque from the rotor. A magnet cover is provided to cover at least a part of the magnet. The speed reducer includes a sun gear, a planetary gear, a carrier, a first ring gear, and a second ring gear. The carrier is provided on a radially outer side of the sun gear and on a radially inner side of the first ring gear and the second ring gear to come into contact with the magnet cover or the rotation portion.

Abstract: A prime mover includes a stator fixed to a housing and a rotor provided rotatably relative to the stator, and is capable of outputting a torque from the rotor. A speed reducer includes a sun gear, multiple planetary gears, a carrier, a first ring gear, and a second ring gear. The sun gear receives the torque from the rotor. The rotor is provided on a radially inner side of the stator, and is connected to the sun gear to be rotatable integrally with the sun gear.

Abstract: A prime mover is provided in a housing, and can operate by energization and output a torque. A speed reducer can decelerate and output the torque of the prime mover. A rotational translation unit including a rotation portion that rotates relative to the housing when the torque output from the speed reducer is input, and a translation portion that moves relative to the housing in an axial direction when the rotation portion rotates relative to the housing and can change a state of a clutch to an engaged state or a non-engaged state. The speed reducer includes an output unit that outputs the decelerated torque of the prime mover to the rotation portion. The rotation portion is formed of a material different from that of the output unit separately, and is provided to be rotatable integrally with the output unit.