Patent · US Expired

Hydrostatic drive system

US5931078A · kind A · utility

9Cited by
4References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 18, 1997
Grant dateAug 3, 1999
Priority date
Expiry dateApr 18, 2017

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF15B2211/75
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A hydrostatic drive system has a demand-responsive pump and at least one hydraulic circuit or consumer connected to it. Each consumer can be actuated by a directional control valve which acts as a throttle in intermediate positions. For the distribution of the delivery flow independently of the load, a pressure-maintaining valve is located upstream of the directional control valve. The pressure-maintaining valve can be controlled by a differential signal formed from a load pressure signal and a delivery pressure signal. The load pressure signal to the pressure-maintaining valve of the consumer can be changed by the output signal of a pressure reducing valve. One control surface of the pressure-maintaining valve can be pressurized with the output-side pressure of the pressure reducing valve which is located in a load pressure line. The output pressure of the pressure reducing valve can be adjusted by a spring and a variable control pressure.

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