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. 01, 1985
Filed:
Jul. 14, 1983
Lucien B Shuler, Bettendorf, IA (US);
Caterpillar Tractor Co., Peoria, IL (US);
Abstract
Hydrostatic transmissions are commonly employed in the drive train of earthmoving and industrial vehicles. It is difficult to stop some such vehicles at a precise location on a slope due to the presence of a delay valve included in the controls for delaying application of a friction brake until the vehicle has been stopped by the hydrostatic transmission. In the present control system, a manual control valve (74) is moved to a first operative position and a hand control lever (25) is manipulated in combination therewith to reduce the displacement of a variable displacement pump (12) to establish a minimum drive condition sufficient to hold the vehicle motionless. Thereafter the manual control valve (74) can be moved to a second operative position to apply a friction brake (18) while the transmission maintains the vehicle motionless. In order to start the vehicle from the stopped position on a slope without unwanted roll, the transmission is either maintained at the minimum drive condition while the vehicle is stopped or the control lever (25) is manipulated to reestablish the minimum drive condition such that when the friction brake (18 ) is released by returning the control valve (74) to the first operative position, no undesired vehicle motion will occur. Normal vehicle motion may then resume by further manipulation of the control lever (25) and/or the manual control valve (74).