FLUID PRESSURE ACTUATOR

To provide a fluid pressure actuator by which a drive operator can safely perform a drive operation without causing an erroneous operation even in an operation under a severe environment not allowing an easy approach of a person.SOLUTION: A fluid pressure actuator AC is provided with: a conversion part 3 having a conversion unit 3U which comprises a conversion piston 32 (displacement body) arranged so as to be displaceable in a conversion pressure chamber 310 formed in a conversion cylinder 31 (conversion unit main body), and in which the conversion piston 32 is displaced according to a quantity which is supplied when either of working oil FL1 (drive-side working fluid) and working water FL2 (driven-side working fluid) is supplied to the conversion pressure chamber 310, and the other of the working oil FL1 (drive-side working fluid) and the working water FL2 (driven-side working fluid) is discharged from the conversion pressure chamber 310; and displacement detection means 4 for measuring a displacement amount of the conversion piston 32.SELECTED DRAWING: Figure 1 【課題】人が近づくことの困難な過酷な環境下での運用であっても、誤作動することなく、運転作業者が安全に運転操作を行うことができる流体圧アクチュエータを提供する。【解決手段】変換シリンダ３１（変換ユニット本体）内部に形成される変換圧力室３１０内を変位可能に配置された変換ピストン３２（変位体）を具備し、作動油ＦＬ１（駆動側作動流体）と作動水ＦＬ２（従動側作動流体）とのどちらか一方が変換圧力室３１０に供給された際に、供給された量に応じて変換ピストン３２が変位し、作動油ＦＬ１（駆動側作動流体）と作動水ＦＬ２（従動側作動流体）との他方が変換圧力室３１０から排出される変換ユニット３Ｕを具備する変換部３と、変換ピストン３２の変位量を計測する変位検出手段４と、を流体圧アクチュエータＡＣに設ける。【選択図】図１