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:
Sep. 16, 2003
Filed:
Nov. 06, 2001
Mark Duquette, Andover, CT (US);
Kenneth Klopfer, East Hartland, CT (US);
Stanadyne Corporation, Windsor, CT (US);
Abstract
A hydraulically actuated servo piston and hydraulic advance piston are integrated into the cam follower of a unit pump or injector to provide variable advance for an injection event produced by the pump or injector. The servo piston is nested in the advance piston with fluid passageways in the advance piston selectively opened or closed by movement of the servo piston. The full pressure of a hydraulic pump is available to the advance piston for powering the advance function, while stepwise reduced levels of hydraulic pressure from the same hydraulic pump are applied to control movement of the servo piston. A damping orifice restricts flow of hydraulic fluid to and from the servo piston.