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:
Jul. 04, 1989
Filed:
Jun. 16, 1988
Jon R Patton, Coffeyville, KS (US);
Robert W Harris, Coffeyville, KS (US);
Cooper Industries, Inc., Houston, TX (US);
Abstract
A control system for a multi-speed powershift gear transmission having multiple hydraulically actuated speed range clutches and directional clutches includes a control valve module having solenoid operated valves for conducting pressure fluid to a selected one of the speed range clutches and a selected one of the directional clutches. A pressure regulator valve is in circuit with the directional clutch control valves and is acted on by pilot pressure fluid controlled by a proportional solenoid type control valve wherein the pressure rate of rise in the directional clutches may be selectively controlled in accordance with the particular shift condition initiated and based on a previous transmission operating condition. The control unit provides for a predetermined pressure rate of rise signal to the pressure regulator valve based on the selected shift condition and the previous operating condition of the transmission.