Torque transmission joint and electric-powered power steering apparatus

A torque transmission joint comprising:

• a combined body;
• and
• a couple of end transmission members,
• the combined body comprising:
• an intermediate transmission member having an intermediate uneven section with concave portions and convex portions alternately arranged in a circumferential direction;
• and
• a couple of elastic members made of elastic material, the elastic members respectively assembled to the intermediate transmission member at both sides in an axial direction of the combined body and respectively having elastic slits provided at a plurality of positions in the circumferential direction that are in a same phase with the concave portions of the intermediate uneven section, and every space in the circumferential direction of both side edges in the circumferential direction of the elastic slits being made smaller than every space in the circumferential direction of both side edges in the circumferential direction of the concave portions of the intermediate uneven section;
• the couple of end transmission members respectively inserted and arranged in both side sections in the axial direction of the combined body and the couple of end transmission members respectively having an end uneven section with concave portions and convex portions alternately arranged in the circumferential direction;
• and
• at each of the both side sections in the axial direction of the combined body, the convex portions of the end uneven section engaging with the elastic slits as well as engaging with the concave portions of the intermediate uneven section with a gap intervening in the circumferential direction therebetween;
• and
• in at least one of the both side sections in the axial direction of the combined body, the intermediate transmission member having a concave portion in the circumferential direction that is opened in the axial direction and extends in the circumferential direction, and one elastic member of the couple of elastic members having a convex portion in the circumferential direction that protrudes in the axial direction and extends in the circumferential direction, and the convex portion in the circumferential direction contacting to at least one circumferential surface of both circumferential surfaces in a radial direction of an inner surface of the concave portions in the circumferential direction elastically.