Vehicle liftgate counter balance system

摘要

The counter balance system for a vehicle liftgate includes a pair of gas cylinders in combination with a torsion rod. The gas cylinders urge the liftgate toward an open position but due to a short moment arm do not exert sufficient force to open the liftgate until the liftgate has pivoted about one third of the distance from the closed position toward the open position. The torsion rod also urges the liftgate toward an open position. Maximum force is exerted by the torsion rod when the liftgate is closed. As the liftgate moves toward an open position, the force exerted by the torsion rod decreases until the liftgate is midway between closed and open. The torque rod does not exert any force on the liftgate during the last portion of its movement to an open position.