Patent ID: 7874622

Claim:
A vehicle seat reclining device comprising: a first arm adapted to be fixed to one of a seat cushion side and a seat back side of a vehicle seat; a second arm adapted to be fixed to the other of the seat cushion side and the seat back side of the vehicle seat and relatively rotatably supported by the first arm; an internal toothed portion provided in an inner space formed between the first arm and the second arm, the internal toothed portion being formed at the second arm; a pawl provided in the inner space and movably supported by the first arm, the pawl having an external toothed portion engaging with or disengaging from the internal toothed portion in response to the movement of the pawl; a first cam groove formed at a first opposing surface of the pawl opposing to the first arm; a pawl control member rotatably provided in the inner space between the first arm and the first opposing surface and having at least a first projection inserted into the first cam groove, thereby controlling the movement of the pawl by the engagement between the first cam groove and the first projection in response to the rotation of the pawl control member; a second projection formed at a second opposing surface of the pawl opposing to the second arm; and, a second cam groove formed at a second arm side, into which the second projection is inserted and having a restricting portion for restricting the movement of the pawl in a direction to be engaged with the internal toothed portion by the engagement with the second projection and a non-restricting portion provided consecutively from both ends of the restricting portion for allowing the movement of the pawl in the direction to be engaged with the internal toothed portion without engaging with the second projection, wherein the pawl control member includes a release plate provided in the inner space and rotatably disposed between the first arm and the first opposing surface, the release plate including the first projection inserted into the first cam groove and moving the pawl in response to the rotation thereof by the engagement between the first cam groove and the first projection, and a cam rotatably provided in the inner space, fixed to the release plate for unitary rotation therewith and pressing the pawl to be in contact with the internal toothed portion.