a clutch mechanism is provided between a driving rotor and a driven rotor the clutch mechanism selects from a state for transmitting rotational force and a state for discontinuing the transmission of rotational force the holder permits the rolling a holder supports rolling bodies such that the rolling bodies are switched between a transmitting position and a disconnecting position when held at the transmitting position the rolling bodies are engaged with both of the driving rotor and the driven rotor so that rotational force of the driving rotor is transmitted to the driven rotor when held at the disconnecting position the rolling bodies are disengaged from the driving rotor so that the transmission of rotational force from the driven rotor to the driving rotor is discontinued when external rotational force is applied to the driven rotor the holder sets the rolling bodies to the disconnecting position application_number US 18443302 A description an actuator 1 used in a power assisted vehicle door according a first embodiment of the present invention will now be described with reference to fig1 to 4 b the actuator 1 is located in the door the cross sectional view of fig1 is a view taken perpendicular to the extending direction of the actuator 1 the actuator 1 includes a rack 2 which moves linearly along the extending direction of the actuator 1 the distal end of the rack 2 is coupled to the vehicle body at a part displaced from the axis of the hinge by which the door is supported that is the actuator 1 moves the rack 2 linearly to.