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:
Sep. 03, 1991
Filed:
Apr. 30, 1990
David P Ganoung, Albuquerque, NM (US);
Other;
Abstract
A powertrain for passenger cars includes a high specific output engine coupled to an automatic transmission which is expanded from four to five forward speed ratios by a novel two-speed torque converter assembly within the transmission. Both of hydrodynamic action and an integral planetary gearset contribute to torque multiplication provided by the high-stall-speed torque converter when it is in its lower speed ratio, and engagement of a lockup clutch simultaneously deactivates both sources of torque multiplication to thereby establish a 100% efficient one-to-one speed ratio across the converter. Also included in the powertrain in a control system which secures high transmission efficiency early during vehicle acceleration by employing lockup of the torque converter as the first of the four upshifts for the five-speed transmission. Another control system utilizes a drive-by-wire type of engine throttle valve to implement an aggressive gearshift schedule and to limit engine intake air flow under stall conditions of the torque converter. These powertrain features exploit the fuel economy potential of modern high specific output engines and more effectively manage the characteristically peaky torque curve of such engines.