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:
Mar. 31, 2009
Filed:
Aug. 29, 2006
Kevin L. Kluemper, Monrovia, IN (US);
John P. Kresse, Martinsville, IN (US);
Kevin L. Kluemper, Monrovia, IN (US);
John P. Kresse, Martinsville, IN (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A method of releasing a lockup clutch for a fluid coupling assembly disposed between an engine and an automatically shiftable transmission during a negative engine torque mode of operation is provided. The method includes the steps of: A) determining a current engine torque value prior to commanding the engine to ramp to a target engine torque value; B) commanding the engine to a target engine torque value wherein the target engine torque value is one of a zero and near zero value; C) holding the engine at the target engine torque value; and D) releasing or disengaging the lockup clutch when the engine is operating at the target engine torque value. A powertrain is also provided having a controller sufficiently configured to operate according to the method of the present invention.