| 摘要 |
PURPOSE:To obtain a transmitter which is not damaged by an excessive pressure without providing a protective mechanism especially, by using two pieces of hydrostatic pressure sensors of the same kind. CONSTITUTION:A low pressure chamber 3 and a high pressure chamber 4 are formed on both sides of a partition of a columnar body 5, and the inside of both the chambers is filled with an incompressive fluid such as an Si oil, etc. Seal diaphragms 1, 2 are welded to both end faces of the body 5. Hydrostatic pressure sensors 6, 7 are constituted of a semiconductor material having a hydrostatic pressure sensitivity. By hermetic sealing parts 8, 9, lead wires 61, 71 which is connected to the hydrostatic sensors 6, 7 are fetched to the outside of the body 5. A temperature detecting element 10 detects a temperature of the sensors 6, 7, and a lead wire 101 fetches this electric signal. Also, a pressure of a fluid to be measured is led to the chambers 3, 4, and a signal corresponding to a differential pressure of the chambers 3, 4 is obtained by calculating a variation of a resistance of the sensors 6, 7. Also, even if excessive pressures PH, PL are impressed to a transmitter, an external force which gives a damage is not applied at all to the sensors 6, 7 since the chambers 3, 4 are surrounded by a solid wall of the body 5. |
