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:
Nov. 21, 1995
Filed:
Mar. 04, 1994
Gerald L Holbrook, Rochester Hills, MI (US);
Maurice B Leising, Clawson, MI (US);
David L Kwapis, Troy, MI (US);
Chrysler Corporation, Highland Park, MI (US);
Abstract
An electronic transmission coastdown shift control method in which the transmission controller has the capacity to predict timing of apply element application. The control method of the present invention improves the shift sequence by accurately prefilling the apply element. The transmission controller vents the release element when apply element application is imminent and controls the application of the oncoming element to achieve a controlled element exchange for a smooth coastdown shift. A duty cycle is then applied to complete the oncoming element application with a soft yet quick application and control the engagement of the oncoming element. The identification of the application point of the oncoming element enables the apply element fill volume to be learned during coastdown shifts. It also enables the calculation of a line pressure correction factor necessary in accurately predicting application of the apply element. Anticipation of a coastdown tip-in condition is also provided. When a tip-in condition is sensed, a more aggressive fast fill of the apply element is undertaken in order to handle an approaching input torque increase.