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. 26, 2004
Filed:
Feb. 10, 2003
Scott N. Schuh, Fort Ransom, ND (US);
Clark Equipment Company, Woodcliff Lake, NJ (US);
Abstract
A vehicle, such as a loader, has an operator-controlled hydrostatic drive that includes hydrostatic motors to drive wheels. The speed of the motors is proportional to an operator input provided to a controller that regulates the flow of hydraulic fluid from a pressure source to the motors. The regulation of fluid under pressure to the motors is achieved by utilizing electrical displacement control pumps that provide fluid flow in proportion to an input signal. The motors are fixed displacement motors, and when the wheels overrun as the vehicle rolls down an incline, the motors will act as pumps. The movement of the wheels is sensed to provide a signal to the controller to adjust one or both of the control pumps to provide a balancing counter pressure at the work port of the motor to insure that the vehicle will not creep or roll when it should be stopped.