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:
Feb. 23, 1993
Filed:
Sep. 14, 1990
Bak G Sankpal, Rochester, MI (US);
John F Carnago, Trenton, MI (US);
Ford Motor Company, Dearborn, MI (US);
Abstract
To reduce shift bump and increase smoothness during shifts, pressure into an on-coming clutch of an automatic transmission is electronically controlled using a turbine speed adaptive strategy. Because of the change in engine speed that accompanies this torque flow path transition, such shifts include a torque phase and an inertia phase. To make the shift smooth, the torque phase is completed quickly by boosting pressure at the beginning of the shift. Just before the torque phase is commpleted, the pressure is lowered so the inertia phase bump is reduced. The end of the torque phase is predicted by monitoring the turbine speed rise since the start of the shift and comparing it with a value which is derived from an adaptive table. During the inertia phase, the pressure is ramped up to complete the shift quickly and smoothly. Ignition spark timing is reduced in the inertia phase to further improve shift feel.