Abstract: A casing is capable of preventing loosening of screws. A first attachment part of a first casing is fixed to a third surface of a block using a first screw. A second attachment part of a second casing is fixed to a fourth surface of the block using a second screw. Both upper surfaces of the first and the second casing are fixed using a third screw. The first and second screws are arranged on each side in a direction intersecting a longitudinal direction of the first and second casings, and the third screw is arranged on one side in the direction intersecting the longitudinal direction of the first casing.

Abstract: A pressure sensor that can prevent application of excessive stress on a port and detect fluid differential pressure accurately. A base includes a sensor that detects a pressure difference between a first fluid and a second fluid. A first port is attached to the base and has a first flow path through which the first fluid is introduced. A second port is attached to the base and has a second flow path through which the second fluid is introduced. The outer diameter of the first port is equal to the outer diameter of the second port, and the diameter of the first flow path is smaller than the diameter of the second flow path.

Abstract: Embodiments provide a pressure sensor capable of surely filling inside of a housing in which an adjustment member is provided with insulating liquid. A base includes a first flow path to be filled with a first fluid and a first recess communicating with the first flow path. A first diaphragm seals the first recess. A sensor unit is provided in the first recess. An adjustment member is arranged around the sensor unit in the first recess, communicates with the first flow path, and includes a hole introducing the first fluid in the first flow path into the first recess. The first diaphragm includes a plurality of grooves arranged concentrically, and the hole is opposed to one of the plurality of grooves.