Patent · US Expired

Hydraulic system with priority control

US4147034A · kind A · utility

8Cited by
4References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 19, 1978
Grant dateApr 3, 1979
Priority date
Expiry dateApr 19, 1998

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF15B2211/78
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A hydraulic system including a pressure and flow compensated pump, a source of pilot fluid under pressure, a plurality of hydraulic circuits each including a work performing device, a plurality of controls, one for each circuit, each including a pilot operated flow valve for connecting the associated work performing device to the pump and an operator positioned valve connected to the pilot source for selectively directing pilot fluid to the corresponding flow valve, the work performing devices and the flow valves being connected in parallel. The system further includes a supply margin valve having pressure responsive surfaces respectively connected to the pump and to the work performing devices for providing a control signal to the pump to cause the same to supply fluid at a pressure equal to the pressure required by the work performing devices plus a predetermined margin and a first demand margin valve having pressure responsive surfaces respectively connected to the pump and to the work performing devices for decreasing the pressure of pilot fluid directed to some, but not all, of the operator positioned valves when the predetermined margin is not met. There is further included a…

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