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. 10, 2020
Filed:
Feb. 19, 2018
Ford Global Technologies, Llc, Dearborn, MI (US);
Timothy Fedullo, Northville, MI (US);
Ford Global Technologies, LLC, Dearborn, MI (US);
Abstract
A hydraulically controlled park system disengages a parking pawl in response to engagement of particular shift elements. When the vehicle is one a grade, greater force may be required to dis-engage the pawl, potentially leading to a failure to dis-engage. The controller avoids this failure by engaging an uphill gear ratio and controlling the transmission input torque to transfer load from the parking pawl to the gearing prior to engaging the shift elements that dis-engage the pawl. Following dis-engagement of the parking pawl, the transmission is in a tie-up condition in which the output shaft is held stationary by shift elements. The controller transitions from this tie-up condition to the selected gear ratio by releasing shift elements.