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:
Apr. 08, 2014
Filed:
Jul. 27, 2009
David W. Wright, Howell, MI (US);
Philippe Ramet, Strasbourg, FR;
Morgan Postic, Osthouse, FR;
GM Global Technology Operations LLC, Detroit, MI (US);
Abstract
A method is provided for improving shift quality in an automatic transmission. In many automatic transmissions, the shift quality during lift foot upshifts is unsatisfying. Generally, two types of complaints concerning shift quality are known: harsh feel right after the shift order and bump at the synchronization of the shift. In order to provide an automatic transmission which overcomes these two problems, a first and a second positive torque requests are initiated on upshift coasts. This measure improves the global shift feel by controlling the engine toque level at shift order and at synchronization: the engine torque level at the beginning of the gear shift is smoothly decreased to reduce the initial bump and is controlled at the synchronization to reduce the amplitude of underlap when the clutch capacity is rising.