Dog clutch

A dog clutch having protruding parts provided on one of a driving-side rotating body and a driven-side rotating body and recessed parts provided in the other of the driving-side rotating body and the driven-side rotating body, the protruding parts being adapted to be brought into meshing engagement with the recessed parts to thereby transmit a driving force from the driving-side rotating body to the driven-side rotating body via abutting engagement between side surfaces of the protruding parts and corresponding torque-receiving surfaces of the recessed parts, wherein:

• each of the recessed parts has a bottom face, a strip-shaped island part protruding from the bottom face and extending in a circumferential direction of the driving-side or driven-side rotating body, and groove parts between the island part and the torque-receiving surfaces, the island part receiving a tip surface of the protruding part when the protruding parts are brought into meshing engagement with the recessed parts, and the groove parts preventing top corners of each protruding part from interfering with base corners of a corresponding one of the recessed parts;
• the groove parts and the bottom face are formed by a forging die and have respective surfaces as forged;
• the island part has a cut surface, the cut surface being formed by cutting a top part of the island part after the island part has been formed by the forging die;
• the groove parts are formed so as to be deeper than the bottom face, and the cut surface is formed so as to be shallower than the bottom face;
• the torque-receiving surfaces include a first torque-receiving surface and a second torque-receiving surface that opposes the first torque-receiving surface, the island part extends between the first torque-receiving surface and the second torque-receiving surface so as to have a first end adjacent to the first torque-receiving surface and a second end adjacent to the second torque-receiving surface, and the groove parts include a first groove part disposed between the first end of the island part and the first torque-receiving surface, and a second groove part disposed between the second end of the island part and the second first torque-receiving surface;
• and
• the first groove part is disposed immediately adjacent to the first end of the island part and the first torque-receiving surface, and the second groove part is disposed immediately adjacent to the second end of the island part and the second torque-receiving surface.