Patent ID: 8886428

Claim:
An unlocking controller of an irreversible rotary transmission system that comprises an input shaft that inputs torque from an actuator, an output shaft that outputs torque from the input shaft, and an irreversible rotation transmission element arranged between the input shaft and the output shaft; the irreversible rotation transmission element enacts driving control of the actuator so that, when torque is transmitted from the input shaft to the output shaft, the torque becomes greater than unlocking torque, so that the irreversible rotation transmission element is a lock released state that allows transmission of the torque; in a transmission-off state where the torque is not transmitted from the input shaft to the output shaft, the irreversible rotation transmission element is locked by a load torque of the output shaft, so that transmission of the load torque of the output shaft to the input shaft is prohibited; the unlocking controller comprising: an input shaft rotation direction determination section that determines whether an input shaft rotational direction is the same as, or opposite to, a direction of the load torque of the output shaft; and an unlocking torque setting section that based on to a determination result of the input shaft rotation direction determination section conducts an unlocking torque control that sets the unlocking torque a higher value when the input shaft rotational direction and the direction of the load torque of the output shaft are the same as while the lock is released, than when the input shaft rotational direction is opposite to the direction of the load torque of the output shaft.