Patent attributes
A vehicle seat reclining device includes a lock mechanism. The lock mechanism includes first and second members, which are rotational relative each other, first pawls, and a cam, which moves the first pawls in the radial direction and unlocks or locks the same. The vehicle seat reclining device includes a memory ring, which integrally rotates with the first member or the second member through engagement, partial engagement, or disengagement from the first pawls, an engaging projection, which is located in an accommodating recess of the second member and protrudes radially inward, and a rotation permitting section located on the outer circumferential surface of the memory ring. When the rotation permitting section allows the engaging projection to move, relative rotation within a predetermined rotation range is permitted between the second member and the memory ring.
