Reclining apparatus

A reclining apparatus comprising:

• a bottomed cylindrical first member formed with inner teeth on an inner cylindrical surface along the circumferential direction and having an opened surface on one of the surfaces;
• a second member stacked on the side of the opened surface of the first member and provided so as to be capable of rotating relative to the first member in the circumferential direction;
• a pole provided on the second member so as to be capable of moving and formed with outer teeth capable of engaging the inner teeth;
• a rotation cam arranged on the side of a center axis of the relative rotation with respect to the pole and configured to move the pole to a locked position where the outer teeth of the pole engage the inner teeth of the first member;
• an urging member configured to urge the rotation cam so as to position the pole at the locked position;
• an unlock retaining mechanism including an ark-like guide extending along the circumferential direction formed on the first member on the inner cylindrical surface on the side of a bottom portion with respect to the inner teeth thereof and an abutting portion configured to retain the pole in an unlocked position when abutting against the ark-like guide;
• a spacer provided on the bottom portion of the first member and configured to restrict the pole from moving to the bottom portion of the first member, wherein
• the rotation cam is formed with a through hole having a center at a center of rotation thereof, and
• the spacer is formed with a cylindrical portion to be fitted in the through hole of the rotation cam.