公开(公告)号：US20180282974A1

公开(公告)日：2018-10-04

申请号：US15762641

申请日：2016-09-21

Applicant: KYB Corporation

Inventor： Shunsuke KUBO ,  Jun KIMURA

IPC: E02F9/22 ,  F15B13/02

Abstract: A fluid pressure control device includes a switching valve configured to switch an operation of an operate check valve, a relief valve configured to open when a pressure in a load-side pressure chamber reaches a predetermined pressure, and a relief discharge passage configured to lead a relief fluid discharged from the relief valve to a tank. The switching valve includes a piston giving thrust to a spool upon receipt of a pilot pressure on a back surface, a drain chamber defined by the spool and the piston, and a drain passage allowing the drain chamber and a spring chamber to communicate with the relief discharge passage. The relief fluid discharged from the relief valve is discharged to the tank through the relief discharge passage and does not operate the switching valve.