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:
Apr. 01, 2008
Filed:
Oct. 12, 2006
Leslie Edwin Chapman, Chatham, GB;
Rodney Dyason, Chatham, GB;
Leslie Edwin Chapman, Chatham, GB;
Rodney Dyason, Chatham, GB;
Delphi Technologies, Inc., Troy, MI (US);
Abstract
An advance arrangement for use in controlling timing of fuel delivery by a fuel pump for use in an engine comprises an advance piston () which is slidable within a first bore () and which cooperates, in use, with a cam arrangement of a fuel pump to adjust the timing of fuel delivery by the pump. A surface associated with the advance piston () is exposed to fuel pressure within a first control chamber (). The pressure of fuel within the first control chamber () is controlled by means of a servo piston () which is slidable within a further bore () provided in the advance piston (). The servo piston () is responsive to speed dependent fuel pressure variations within a servo control chamber (), thereby to permit adjustment of the timing in response to engine speed. A light load piston () is moveable relative to the advance piston () against the action of a light load control spring () in response to load dependent fuel pressure variations within a light load control chamber (), thereby to adjust the timing under light load conditions. The light load piston () is carried within a cold cranking sleeve () which is slidable within the first bore () against the action of a cold cranking control spring () in response to fuel pressure variations within a cold cranking control chamber (). Thus, the cranking control spring () acts, in use, to slide the cold cranking sleeve () a predetermined distance in the advance direction and fuel pressure variations within the control chamber () serve to slide the cold cranking sleeve () back in the retard direction.