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. 06, 2003
Filed:
Jun. 11, 2001
Paul Skupinski, Farmington Hills, MI (US);
David Morganroth, Gaines, MI (US);
Marek L. Wilmanowicz, Pinckney, MI (US);
Sheryl Page, Ann Arbor, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
An improved powertrain control minimizes output torque disturbances due to garage shifting. Under certain predefined conditions, garage shifts to the forward or Drive range are carried out by initially commanding a shift to an upper forward gear ratio having a relatively low torque advantage, and then commanding a shift from the upper forward gear ratio to a lower forward ratio that is ordinarily used to launch the vehicle. The shift from the upper gear ratio to the lower gear ratio is initiated when the initial shift is substantially complete or when a predetermined period of time has elapsed since shift initiation. Engine management controls are also used to reduce the transmission input torque during garage shifts to both forward and reverse ranges.