Clutch device

A clutch device comprising:

• a housing;
• a prime mover provided in the housing and including a stator fixed to the housing, and a rotor rotatable relative to the stator, the prime mover being capable of outputting torque;
• a speed reducer configured to output the torque of the prime mover at a reduced speed;
• a rotational translation unit including a rotation portion that rotates relative to the housing upon receiving an input of the torque output from the speed reducer, and a translation portion that moves relative to the housing in an axial direction in accordance with rotation of the rotation portion relative to the housing;
• a clutch provided between a first transmission portion and a second transmission portion that are rotatable relative to the housing, the clutch being configured to allow transmission of torque between the first transmission portion and the second transmission portion in an engaged state of the clutch, and interrupt the transmission of torque between the first transmission portion and the second transmission portion in a disengaged state of the clutch;
• a state changing unit configured to receive a force along the axial direction from the translation portion and change a state of the clutch to the engaged state or the disengaged state according to a position of the translation portion in the axial direction relative to the housing;
• and
• a return spring configured to urge the rotational translation unit relative to the housing in a direction away from the clutch, wherein
• the return spring, the rotational translation unit and the housing are assembled integrally while an initial set load being applied to the return spring, and the rotational translation unit is sandwiched between the return spring and the housing while the return spring urging the rotational translation unit;
• and
• the stator and the rotor are each entirely housed in the housing, and the rotor and the rotation portion are coaxial.

A clutch device comprising:

• a housing;
• a prime mover provided in the housing and capable of outputting torque;
• a speed reducer configured to output the torque of the prime mover at a reduced speed;
• a rotational translation unit including a rotation portion that rotates relative to the housing upon receiving an input of the torque output from the speed reducer, and a translation portion that moves relative to the housing in an axial direction in accordance with rotation of the rotation portion relative to the housing;
• a clutch provided between a first transmission portion and a second transmission portion that are rotatable relative to the housing, the clutch being configured to allow transmission of torque between the first transmission portion and the second transmission portion in an engaged state of the clutch, and interrupt the transmission of torque between the first transmission portion and the second transmission portion in a disengaged state of the clutch;
• a state changing unit configured to receive a force along the axial direction from the translation portion and change a state of the clutch to the engaged state or the disengaged state according to a position of the translation portion in the axial direction relative to the housing;
• and
• a return spring configured to urge the rotational translation unit relative to the housing in a direction away from the clutch, wherein
• the housing has an acting surface on which an urging force of the return spring acts through the rotational translation unit,
• a surface of the housing opposite from the acting surface has a housing recess portion recessed toward the acting surface, and
• an end surface of an a flange in the axial direction is in contact with a bottom surface of the housing recess portion in a state where the housing is attached to the flange.