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:
Aug. 28, 2012
Filed:
Jan. 25, 2010
Andrew L. Mitchell, Indianapolis, IN (US);
Jeffrey K. Runde, Fishers, IN (US);
Brett R. Caldwell, New Palestine, IN (US);
Andrew L. Mitchell, Indianapolis, IN (US);
Jeffrey K. Runde, Fishers, IN (US);
Brett R. Caldwell, New Palestine, IN (US);
GM Global Technology Operations LLC, Detroit, MI (US);
Abstract
An improved downshift control for an automatic transmission optimized for sequential shifting achieves a non-sequential fifth gear to third gear downshift by reducing the main pressure of the transmission hydraulic control system, allowing a offgoing clutch to slip, disengaging the offgoing clutch, using torque reduction to control engine speed, engaging the oncoming clutch, increasing the main pressure of the transmission hydraulic control system and using torque reduction to synchronize the transmission input speed with the third gear transmission output speed.