Patent · US Expired

Flow control system

US5460001A · kind A · utility

14Cited by
6References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 7, 1994
Grant dateOct 24, 1995
Priority date
Expiry dateNov 7, 2014

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF15B2211/50536
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A flow control system is arranged in a hydraulic circuit provided with a variable displacement hydraulic pump, plural actuators and a pump controller. The pump controller controls the displacement of the pump so that a delivery pressure becomes higher by a predetermined value than a maximum load pressure of the plural actuators, whereby the flow rate of pressure oil to the actuators is controlled. The system includes plural valve units connected between the pump and the actuators. Each valve unit has an operating and correcting variable restrictors. The system also includes pressure compensation valves, which are each arranged on an upstream side of a restrictor group consisting of the operating and correcting variable restrictors. The opening of the pressure compensation valve is independently set by an opening drive force set based on a downstream pressure of the restrictor group, an opening drive force set by a pressure-difference setting device and a closing drive force set based on an upstream pressure of the restrictor group so that the upstream pressure becomes higher by a predetermined pressure than the downstream pressure of the restrictor group.

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