Seat back reclining mechanism

摘要

A seat back reclining mechanism for a vehicle seat includes an upper and lower brackets respectively secured to the seat back and the seat cushion. A reduction gear mechanism is provided between the upper and lower brackets for a stepless adjustment of the reclining angle. An actuating knob is located at one side of the seat cushion for the convenience of operation. A belt-sprocket type motion transmitting mechanism is provided between the actuating knob and the reduction gear mechanism for transmitting a rotation of the knob to the gear mechanism. In order to prevent the seat back from being inclined under the load applied by the passenger, a constraining device is provided for preventing the motion transmitting mechanism from transmitting the force from the reduction gear mechanism.