摘要 |
A solid state measurand sensor is described in which the pressure sensor element is protected from the measurand by a combination of a pressure transfer medium and a thin covering membrane. A method is described for forming the diaphragm in situ. The diaphragm material is selected from a group of materials which includes fluorosilicone, so as to substantially avoid entrapment of air or formation of voids in the pressure transfer medium such as would degrade the performance of the sensor. The pressure transfer medium is gel-like material such as dimethyl silicone and equivalents. Alternatively, the gel may be fluorosilicone and the diaphragm may be dimethyl silicone. The membrane material is chosen to be substantially impermeable to the ambients or process media being measured and also flexible, is to be poured and cured in place on the assembly during fabrication.
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