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. 09, 2008
Filed:
May. 22, 2007
Martin P Hardy, Gillingham, GB;
Christopher a Goat, North Meadow Offham, GB;
Michael P Cooke, Gillingham, GB;
Andrew John Hargreaves, Boughton Under Blean, GB;
Jean-francois Berlemont, Bascharage, LU;
Martin P Hardy, Gillingham, GB;
Christopher A Goat, North Meadow Offham, GB;
Michael P Cooke, Gillingham, GB;
Andrew John Hargreaves, Boughton Under Blean, GB;
Jean-Francois Berlemont, Bascharage, LU;
Delphi Technologies, Inc., Troy, MI (US);
Abstract
A method of operating a fuel injector including a piezoelectric actuator having a stack of piezoelectric elements, comprises applying a discharge current (I) to the actuator for a discharge period so to discharge the stack from a first differential voltage level across the stack to a second, lower differential voltage level across the stack so as to initiate an injection event, and applying a charge current (I) to the actuator for a charge period (Tto T') so as to charge the stack from the second differential voltage level to a third differential voltage level so as to terminate the injection event. The method includes determining at least one engine parameter (e.g. common rail pressure) of the injection event prior to applying the charge current (I) to the actuator and selecting the third differential voltage level in dependence on the at least one engine parameter.