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:
Nov. 11, 2003
Filed:
Jan. 28, 2002
Gladys L. Evans, Dubuque, IA (US);
Judson P. Clark, Dubuque, IA (US);
Glenn Owen Scheer, Durango, IA (US);
William Michael Walter, Galena, IL (US);
William Daniel Robinson, Epworth, IA (US);
David William Stubben, Dubuque, IA (US);
Alfred Sigmund Smemo, Dubuque, IA (US);
Deere & Company, Moline, IL (US);
Abstract
A dual path hydrostatic drive system having an electronic auxiliary drive auxiliary drive controller controlling the hydraulic output of left and right variable displacement pumps in response to the speed of the main drive wheels and a speed ratio signal from a speed ratio input control. In addition, the auxiliary drive auxiliary drive controller controls the outputs of the pumps within three basic boundary conditions; a hydraulic pressure boundary condition, a motor speed boundary condition and a power boundary condition. A clutch mode activation switch has two positions for signaling the auxiliary drive auxiliary drive controller to operate in a first mode in which the auxiliary drive system is shut down upon activation of the main clutch or a second mode where the auxiliary drive controller attempts to mirror the operation of the main drive wheels.