Abstract: After a door is super-locked by an electric motor, the door cannot be unlocked by a manual control knob for passenger's safety and for burglarproof. The door-lock unit and other components including the electric motor and a door-lock unit are protected from a violent force applied on the knob or some other components even if an inappropriate attempt to open the door in such occasion. In the actuator, an output lever which is connected to the door-lock unit rotatably disposed on an input lever which is connected to the knob. A clutch lever is connected to the torque transmitting mechanism and is rotatably disposed on the output lever. When the door is super-locked, the output lever is retained by a stopper, and only the clutch lever is rotated counterclockwise so that the clutch arm disengages from the input lever. As a result, even if the knob is drawn forcibly to unlock the door, only the input lever is rotated as the knob is moved and no violent force is applied on the door-lock unit or the electric motor.

Abstract: An overload safety device is provided for use on a feed mechanism to control the feed of such devices as a headstock, tool rest, or rotary table. The overload safety device includes a mounting means for maintaining a feed screw in a fixed position with respect to an axis of rotation of the screw and for permitting the screw to move a predetermined distance along the axis in response to a load placed thereon. The safety device further includes control means responsive to the movement of the screw for producing a control signal when the movement of the screw exceeds the predetermined distance, thus indicating an overload condition.