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:
Dec. 22, 1981
Filed:
Mar. 27, 1980
Frederic W Pollman, Ames, IA (US);
Sundstrand Corporation, Rockford, IL (US);
Abstract
A three-mode, hydromechanical transmission including a pair of hydraulic displacement units forming a hydrostatic transmission and having a first, low-speed hydrostatic mode and a second and third intermediate and high speed hydromechanical modes. In one embodiment, a pair of planetary gear sets are related to form a four-element differential and are associated with an input shaft and the hydrostatic transmission and brake and clutch means. The hydrostatic transmission drives an output shaft through a connection to one of the planetary gear sets, with the brake means engaged. A first clutch means in a drive train from the input shaft to one planetary gear set effects the second mode of operation with the brake disengaged and a second clutch means in a parallel drive train to another element of the planetary gear sets effects the third mode of operation, with the brake and first clutch means disengaged. In another embodiment, three planetary gear sets are utilized to provide the same three modes of operation, with an extended third mode and with the brake means connected to an element in at least two of the planetary gear sets and with one of said drive trains also being connected to an element in more than one of the planetary gear sets.