US 11,815,107 B2
Fluid control device
Michihiro Niwa, Kyoto (JP)
Assigned to SHIMADZU CORPORATION, Kyoto (JP)
Appl. No. 17/293,906
Filed by SHIMADZU CORPORATION, Kyoto (JP)
PCT Filed Nov. 14, 2018, PCT No. PCT/JP2018/042158
§ 371(c)(1), (2) Date Jul. 16, 2021,
PCT Pub. No. WO2020/100236, PCT Pub. Date May 22, 2020.
Prior Publication US 2022/0003249 A1, Jan. 6, 2022
Int. Cl. F15B 11/16 (2006.01); B66F 9/22 (2006.01)
CPC F15B 11/163 (2013.01) [B66F 9/22 (2013.01); F15B 2211/30555 (2013.01); F15B 2211/3111 (2013.01); F15B 2211/6054 (2013.01); F15B 2211/6055 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A fluid control device of a closed center circuit type having a configuration in which a plurality of fluid control valves are arranged in a row, the fluid control valves each including a body having a port connected to an actuator, a flowrate adjusting member configured to adjust a flowrate of a hydraulic fluid passing through a flow path formed in the body, and a pressure compensation valve, the fluid control device comprising:
a main relief valve corresponding to a pressure of a hydraulic fluid supplied to a fluid control valve having a maximum load pressure among the plurality of fluid control valves;
a secondary relief valve corresponding to a pressure of a hydraulic fluid supplied to a plurality of fluid control valves other than the fluid control valve having the maximum load pressure among the plurality of fluid control valves;
a first passage connecting a load handling line of the fluid control valve having the maximum load pressure among the plurality of fluid control valves, the main relief valve, and the pressure compensation valves in the plurality of respective fluid control valves;
a second passage connecting load handling lines of the plurality of fluid control valves other than the fluid control valve having the maximum load pressure among the plurality of fluid control valves and the secondary relief valve;
check valves disposed in respective passages connecting the load handling lines of the plurality of fluid control valves other than the fluid control valve having the maximum load pressure among the plurality of fluid control valves and the second passage; and
a passage switching unit configured to send a hydraulic fluid having a higher pressure out of the hydraulic fluid in the load handling line of the fluid control valve having the maximum load pressure among the plurality of fluid control valves and the hydraulic fluid in the second passage to the main relief valve and the pressure compensation valves in the plurality of respective fluid control valves through the first passage.