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:
Oct. 04, 1994
Filed:
Aug. 31, 1992
Martin R Dadel, Plainfield, IN (US);
Bradley L McCafferty, Zionsville, IN (US);
Phillip F McCauley, Zionsville, IN (US);
General Motors Corporation, Detroit, MI (US);
Abstract
An electronically controlled hydrodynamic retarder interconnects with the output shaft of a vehicle transmission to selectively apply a braking torque thereto. The retarder includes a solenoid valve, the operating duty cycle of which controls the retarder capacity and resultant braking torque. A control unit, interconnecting the transmission and the retarder, regulates the duty cycle of the solenoid valve to regulate the retarder operation as a function of excessive deceleration or overheating, while also regulating such operation during downshift to assure efficient, effective, and comfortable operation of the transmission/retarder. The retarder is adaptive to accommodate variations resulting from age, wear, and the like.