The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 01, 2000
Filed:
Jun. 26, 1998
Robert Wayne Baughman, Mt. Clemens, MI (US);
David Joseph Chapman, Sterling Heights, MI (US);
Michael Antonio Ciavaglia, Dearborn, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
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.