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:
Aug. 29, 2000
Filed:
Feb. 13, 1998
Kerry G Geringer, Ames, IA (US);
Sauer Inc., Ames, IA (US);
Abstract
A ganged pumping apparatus includes first and second variable displacement open circuit pumps, each having a load sensing control and a servo actuator together for changing the fluid displacement of each pump respectively. The load sensing controls being adjusted so that the setting of the control on the second pump is lower than the setting of the control on the first pump. The servo actuator of the first pump having over-center capability, allowing the first pump to operate with negative fluid displacement, and the servo actuator of the second pump having a stop to limit minimum displacement to non-negative or zero displacement. A single pressure compensating pilot valve disposed in the first pump provides the pressure compensation function of both pumps. A pilot signal line interconnects the pressure compensating pilot valve, the load sensing controls, and a load such that the flow output of the pumps is combinable into a single output and functions as a single large displacement pump. A method of ganging and phasing the pumps is also disclosed.