| 摘要 |
PURPOSE:To enhance reliability and reproducibility, by welding a plate shaped metal diaphragm which receives fluid pressures from two points in a system to one of members forming pressure chambers, with the welding width similar to the magnitude of the thickness of the diaphragm being provided, and compressing the diaphragm with the other member. CONSTITUTION:A sensor part 100 enclosing a semiconductor pressure difference sensor 101 is communicated to a pressure receiving part 1, with high and low pressure chambers 9 and 10, overload protection chambers 5 and 6, and pressure introducing paths 105 and 106, and high and low sealing parts are formed. Non-compressible silicon oil is filled in the inside. The peripheral parts of the high and low pressure sealing diaphragms 7 and 8 are welded to main bodies 2 and 3. The volumes of the overload protection chambers 5 and 6 are larger than those of the pressure receiving chambers 9 and 10. A diaphragm 4 is not seated by the excessive pressure. The peripheral part of corrosion resisting rolled metal of the central diaphragm 4 is welded to the main body 2, with the welding width similar to the magnitude of the thickness of diaphragm being provided, and compressed by the main body 3. The pressure of the fluid through fluid introducing holes compresses the diaphragm 7 and 8, and the pressure difference is sensed by the sensor 101. In this constitution, the transmitting device characterized by stable zero point and excellent reproducilibity can be formed. |
