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. 28, 1976
Filed:
Mar. 27, 1975
James C Polak, Indianapolis, IN (US);
Phillip J Ross, Brownsburg, IN (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A hydromechanical transmission in which the first and second drive ranges are input-split drives. In one embodiment the transmission includes a hydrostatic portion comprised of two hydraulically interconnected, variable displacement, hydraulic pump-motor units and two planetary gear sets which are controlled by a brake and a clutch to provide the two ranges. In another embodiment a third planetary gear set and a second clutch are added to provide increased torque coverage in first range and also provide a third drive range. In both embodiments the speed ratio within the drive ranges is varied by controlling the displacement ratio between the pump-motor units. The shifting from one drive range to another occurs at synchronous speeds, thereby reducing the shift energy absorption required in the clutches and brakes.