Patent · US Expired

Load supporting hydraulic circuit with emergency automatic load restraint

US4417502A · kind A · utility

16Cited by
7References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 17, 1980
Grant dateNov 29, 1983
Priority date
Expiry dateNov 17, 2000

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF15B2211/8636
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A load supporting hydraulic system having main control valve provided with a load check valve and a vent valve; the load check valve, which has a hose connection to the main control valve, is operative to permit free flow of fluid from the control valve toward the load supporting chamber of the system and to block fluid flow from the load supporting chamber toward the control valve, whereas the vent valve is operative with the control valve to permit the load check valve to be opened by fluid pressure from the load supporting chamber to allow fluid flow therefrom thru the hose connection and control valve to drain. A cancelling valve is added to the system to override the vent valve upon failure of the hose connection and reblock fluid flow from the load supporting chamber toward the hose connection and control valve.

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