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:
May. 03, 1994
Filed:
May. 19, 1992
Todd R Berger, Plymouth, MI (US);
Tsunlock A Yu, Saline, MI (US);
Scott B Pollack, Livonia, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
In a neutral to drive shift timing control mechanism, a flow control arrangement is utilized in an electro-hydraulic control system for controlling a clutch fill period of a neutral to drive shift sequence. The hydraulic control system provides a pressure pulse of predetermined time which opens a valve to permit fluid flow to bypass an accumulator feed orifice to pressurize the clutch apply cylinder and piston to a value substantially equal to the piston return spring force without providing excess flow to the accumulator. The clutch apply pressure is then permitted to increase at a more normal rate which is controlled by the accumulator. The engagement time is determined so that the pulse time can be adjusted if the neutral to drive shift is not within a predetermined time range.