DIFFERENTIAL PRESSURE SENSOR AND METHOD OF MANUFACTURING THE SAME

摘要

An industrial machine such as a civil engineering machine and a construction machine, comprising a hydraulic system in a driving system thereof, wherein conditions of pressure in respective portions of the hydraulic system are detected as differential pressure information. A diaphragm whose front and rear surfaces serve as pressure receiving surfaces and a distortion detecting portion formed on one of the pressure receiving surfaces comprise a detecting portion. Pressure medium is introduced onto the two pressure receiving surfaces. Particularly, a sheet member is provided between the pressure receiving surface having the distortion detecting portion and the pressure medium, and, this simplified construction achieves a satisfactory protection. As a sheet member fitting structure, two supporting members for clamping the diaphragm from opposite sides to fix are prepared, and, these supporting members are worked into desired forms, to thereby form a space for housing a signal lead-out-connection portion which is separated from the pressure medium. An electrical wiring portion is also protected in non-contact with the pressure medium.