Patent ID: 8366197

Claim:
An angle adjustment apparatus for a vehicle seat, the apparatus angle-adjustably connecting a first seat member and a second seat member of the vehicle seat, the apparatus comprising: a first member attached to the first seat member; a second member attached to the second seat member and rotatably mounted to the first member; a lock member axially movably provided between the first member and the second member; a movement mechanism axially moving the lock member relative to the first member; and a mount member regulating the first member and the second member from being axially disengaged, the mount member comprising: a ring main body covering external peripheral surfaces of the first member and the second member; a first overhang projecting from the ring main body toward the first member, and regulating the first member from being disengaged from the second member; and a second overhang projectin from the ring main body toward the second member, and regulating the second member from being disengaged from the first member, wherein the first member has first teeth on a surface facing the lock member, the lock member has second teeth and a rotation regulation portion, the second teeth being engagable with the first teeth at a position radially external to a rotation center of the first member and the second member, the rotation regulation portion being engaged with the second member and regulating the lock member from being axially rotated relative to the second member, the movement mechanism has an input member and a drive member, the input member being provided at the rotation center of the first member and the second member, and being regulated from being axially moved relative to one of the first member and the second member, the drive member being provided between an external peripheral surface of the input member and the lock member, and being regulated from being axially moved relative to the lock member, a first engagement portion is provided to the external peripheral surface of the input member, a second engagement portion engaged with the first engagement portion is provided to the drive member, and at least one of the first engagement portion and the second engagement portion extends axially and circumferentially from one of the external peripheral surface of the input member and the drive member, respectively.