of entrapped obstacles when the actual speed of the motor reaches to an entrapment judgment speed which is set lower than the target speed the control unit sets a threshold speed which is higher than the target speed and outputs an output duty to the motor for achieving the target speed by feedback control the control unit switches the output duty after the actual speed of the motor becomes higher than the threshold speed to an output by feedforward control based on the target speed application_number US 40826303 A description a preferred embodiments of the present invention will be explained referring to drawings 0021 fig1 shows a back door 10 of a vehicle which corresponds to an opening and closing member the back door 10 is hinged on a body 17 of the vehicle and is driven by a drive unit 13 so as to open and close a rear opening of the body 17 the drive unit 13 fixed to the body 17 and includes a motor 14 and a driving mechanism 15 unitary connected one another the driving mechanism 15 is connected to the back door 10 through door arms 11 12 when the motor 14 is operated by a control device 16.