Document Type and Number:
Japanese Patent JPS5030117
Kind Code:
A
Abstract:
The invention relates to a valve assembly for hydraulic systems which has the excess pressure relief function of opening when the upstream pressure exceeds the downstream pressure by a predetermined amount and the refilling function of opening when the downstream pressure exceeds the upstream pressure by a predetermined amount. Both functions involve forms of spring load valves and although one such valve is entirely contained within the other, the flow cross sections are substantially the same or at least have the same order of magnitude. The valve assembly includes an axially movable valve body which forms four pressure chambers with the casing and has four pressure faces to effect axial biasing of the valve body when subjected to fluid pressure in the pressure chambers. Restrictors are used to obtain desired pressures in two of the pressure chambers.
Application Number:
JP4209174A
Publication Date:
March 26, 1975
Filing Date:
April 15, 1974
Export Citation:
International Classes:
F15B7/06; F16K17/196; F15B11/00; F15B13/00; F15B21/04; (IPC1-7): F15B7/06