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:
May. 09, 2006
Filed:
Aug. 18, 2005
Zongxuan Sun, Troy, MI (US);
Rodney B. Rask, Grosse Pointe Woods, MI (US);
Zongxuan Sun, Troy, MI (US);
Rodney B. Rask, Grosse Pointe Woods, MI (US);
GM Global Technology Operations, Inc., Detroit, MI (US);
Abstract
Electro-hydraulic engine valve actuation system providing an actuator and an actuator control system. The actuator includes primary and secondary actuation chambers, defined by a piston, connected to the engine valve, and characterized by increasing and correspondingly decreasing chamber volumes, as the piston is urged away from neutral position. A fluid inlet is connected to a flow control valve. A control valve includes an actuator, and has flow states for controlling flow between two fluid inlets and a fluid outlet. The control valve includes first and second opposed, control chambers, each connected to the actuator. There is a spring in the second control chamber. The actuator of the flow control valve is controlled to a first and second state, and there is an electrically uncontrolled third flow state. There is a pair of temperature-compensated orifices which create internal feedback, with the control chambers, between the engine valve motion and the control valve position.