PROBLEM TO BE SOLVED: To provide a pressure sensor capable of preventing liquid in a gas phase section leaked from a liquid phase section from reaching a pressure detection sensor.SOLUTION: The pressure detector comprises: a case C connectable to a liquid flow passage； and a diaphragm member M which is mounted within the case C, partitions a liquid phase section S1 into which a liquid for the flow passage can be filled and a gas phase section S2 into which a gas can be filled, and is displaceable according to the pressure of the liquid filled in the liquid phase section S1； the pressure detector detecting the pressure of the gas phase section S2 by a pressure detection sensor P to detect the pressure of the liquid in the flow passage. The pressure detector further has a hydrophobic membrane B installed between the gas phase section S2 and the pressure detection sensor P that permits passage of the gas but obstructs passage of the liquid.SELECTED DRAWING: Figure 4COPYRIGHT: (C)2020,JPO&INPIT【課題】気相部に漏れた液相部の液体が圧力検出センサに至るのを防止することができる圧力検出器を提供する。【解決手段】液体の流路に接続可能なケースＣと、ケースＣ内に取り付けられ、流路の液体を充填し得る液相部Ｓ１と、気体を充填し得る気相部Ｓ２とを区画するとともに、液相部Ｓ１に充填された液体の圧力に応じて変位可能な膜部材Ｍとを具備し、気相部Ｓ２の圧力を圧力検出センサＰで検出することにより流路における液体の圧力を検出する圧力検出器において、気相部Ｓ２と圧力検出センサＰとの間には、気体の通過を許容しつつ液体の通過を遮断する疎水性膜Ｂが取り付けられたものである。【選択図】図４
