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:
Jan. 29, 2008
Filed:
Feb. 14, 2004
Jy-jen F. Sah, West Bloomfield, MI (US);
Todd M Steinmetz, Indianapolis, IN (US);
Jy-Jen F. Sah, West Bloomfield, MI (US);
Todd M Steinmetz, Indianapolis, IN (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A shift control for an electrically variable transmission shifts between modes through a neutral mode wherein the output is decoupled from the transmission. Normally, shifts between modes are accomplished synchronously through a duration of fixed-ratio operation. Extreme driving conditions may invoke shifts through neutral mode. Ratio violations characterized by one mode being active in a preferred input/output ratio range for another mode are handled by a shift through neutral. Similarly, rapid acceleration and deceleration conditions likely to result in undesirable engine speeds if synchronous shifting is employed are handled by a shift through neutral.