Patent · US Expired

Failsafe electrohydraulic control system for variable displacement pump

US4823552A · kind A · utility

86Cited by
27References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 29, 1987
Grant dateApr 25, 1989
Priority date
Expiry dateApr 29, 2007

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF04B49/065
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

An electrohydraulic system for control of a variable output pump includes a microprocessor-based controller receiving inputs from condition sensors coupled to the pump and command inputs from a remote master controller. The controller supplies outputs to an electrohydraulic valve for metering hydraulic fluid to a pump control port and thereby controlling pump operation in any one of a number of preselected and prestored pump control modes. A hydromechanical valve is connected in parallel with the electrohydraulic valve for controlling pump operation in the event of electrical malfunction or failure. Circuitry connected between the pump condition sensors and the control computer prevents aliasing errors due to mismatch between the computer sampling frequency and pump speed. A pump torque sensor measures pump input shaft torque.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.