Clutch device and motor unit

A clutch device comprising:

• an input disk to be rotated by drive force from an input side;
• an output disk configured to transmit rotation of the input disk to an output side;
• and
• a biasing member configured to press the input disk and the output disk against each other,
• wherein the input disk and the output disk are provided so as to contact or separate from each other in an axial direction, and at opposing surfaces thereof, respectively have tooth portions engageable with or disengageable from each other in association with contact or separation of the input disk and the output disk,
• at each tooth portion, recessed and raised portions extending in a radial direction are alternately provided in a circumferential direction,
• each of the recessed and raised portions is formed in such a curved surface that a width in the circumferential direction continuously expands toward an outside in the radial direction,
• engagement force in the axial direction is greater on an inside of the tooth portions in the radial direction than on the outside in a state in which the tooth portions of the input disk and the output disk are fitted in each other by pressing by the biasing member, and
• the input disk receives the pressing force from the biasing member through an intermediate member having a higher stiffness than that of the input disk.