Patent ID: 7201447

Claim:
A seat reclining device in which a seat belt is fixed to a seat back at one side comprising: a pair of upper arms mounted on the seat back; a pair of lower arms fixed to a seat cushion at both sides, with the upper arms being rotatable relative to the lower arms; a pair of locking mechanisms restricting a rotation of the upper arms relative to the lower arms; a connecting mechanism unlocking both locking mechanisms; an operation handle provided at one locking mechanism; the other locking mechanism being unlocked in response to operation of the operation handle through the connecting mechanism, under the condition that the operation handle is operated to unlock one locking mechanism, the one locking mechanism, the operation handle, the connecting mechanism and the other locking mechanism are engageable with each other to operate together, and under the condition that the one side of the seat back fixed to the seat belt is more deformed by tension of the seat belt than the other side of the seat back, any engagement among the one locking mechanism, the operation handle, the connecting mechanism and the other locking mechanism is disengaged so that the one locking mechanism cannot operate together with the other locking mechanism.