| 摘要 |
Provided is a vehicle seat reclining device capable of performing the angle adjustment of a seatback smoothly. The device has an internal gear 12 formed on a gear plate 1 secured to a lower arm, an external gear formed on an upper arm 2 to be meshed with the internal gear and being fewer by at least one tooth than the internal gear, wedge members 7a, 7b frictionally engageable with the gear plate or the upper arm and frictionally disengageable therefrom, a spring 9 arranged between the wedge members and urging the wedge members in a direction for friction engagement with either one of the gear plate and the upper arm, a drive shaft 6 for pushing and rotating either one of the wedge members in a direction to release the friction engagement, and a ring member 75a arranged between either one of the gear plate and the upper arm and the wedge members to be relatively rotatable for rotating together with the wedge members relative to the other of the gear plate and the upper arm during rotation of the drive shaft. |
