contra-propeller(整流板) Control hydraulic(控制液压) 还有相关的词语也可以参考，也许有用：)~ 液压驱动泵medium 液压泵 fluid clutch 液压回路Hydraulic circuitv 进油和回油节流调速Flow control valves in inlet and outlet lines 双缸顺序控制Sequence control with two cylinders 快进回路Rapid-traverse feed circuit 差动回路Differential circuit 分流阀Flow divider 位移-步骤图Displacement-step diagram 电液压系统 Electrohydraulics
