公开(公告)号：US10145391B2

公开(公告)日：2018-12-04

申请号：US15120773

申请日：2014-12-16

Applicant: KYB Corporation

Inventor： Shunsuke Fukuda ,  Nobuyoshi Yoshida

IPC: F15B11/17 ,  F15B11/02 ,  E02F9/22 ,  F16K11/07 ,  F16K15/02 ,  F16K31/122

Abstract: A fluid pressure control device for a construction machine includes a first circuit system connected to the first pump; a second circuit system connected to the second pump; a switching valve having a normal position, a straight traveling position and a merging position where the working fluid of the branch section is merged into the second neutral passage; and an open/close mechanism configured to open/close the first neutral passage. In a case where at least one of the control valves, on which merging is required, on the downstream of the second traveling control valve is switched to a position other than the neutral position, by closing the first neutral passage by the open/close mechanism and switching the switching valve to the merging position, the working fluid of the first pump is merged into the working fluid of the second pump.