US Patent 9222296 Linear drive actuator for a movable vehicle panel

An apparatus for opening and closing a deck lid of a vehicle body includes a jack-screw type drive unit having two elongated relatively rotatable drive elements which are threadably engaged for controlled bi-directional displacement. An electric motor engages the rotatable drive element. A first mounting device pivotally connects the rotatable drive element to a relatively fixed point on the vehicle. A second mounting device pivotally connects the non-rotatable drive element to the deck lid, or vice versa. The motor is energized to affect bi-directional control of the drive unit while enabling low back-drive effort. A concentric spring counters loading due to the weight of the deck lid.