Patent ID: 9623774
Date: 2017-04-18
CPC Classifications: B60N

Claim:
1. A vehicle seat reclining device comprising a lock mechanism, wherein the lock mechanism includes: a first member, which is fixed to one of a seat cushion component and a seat back component and has a guide groove; a second member, which is fixed to the other one of the seat cushion component and the seat back component, wherein the second member is rotationally supported by the first member and has inner teeth; a first pawl, which is guided by the guide groove of the first member to move in a radial direction and has outer teeth, which are selectively meshed with and separated from the inner teeth of the second member; a cam, which is rotationally arranged in the first member, wherein an urging member, which urges the cam in a direction in which the locking operation is performed, the vehicle seat reclining device comprises: a manipulating member, which rotates the cam in a direction in which the unlocking operation is performed against the urging force of the urging member when in a state of unlocking manipulation; a memory ring, which is rotationally arranged in an accommodating recess located in the second member to be coaxial with the inner teeth in an elastically contracted state, wherein an engaging projection, which is located in the accommodating recess of the second member to project inward in a radial direction; and a rotation permitting portion, which is located on an outer circumferential surface of the memory ring, and when the rotation permitting portion permits movement of the engaging projection, relative rotation of the second member and the memory ring is permitted in a predetermined rotation range.