摘要 |
A flush-mounted sensor measures the pressure of a fluid at a given point of a fluid system such as a container or conduit. A sensor head edge-mounts an isolating diaphragm responsive to the pressure of the fluid. The isolating diaphragm has a small diameter in comparison with the dimensions of the fluid system, is adjacent to the fluid in the system to reduce the dead volume of fluid adjacent the diaphragm and may be formed of a material that is compatible with the fluid. A drive rod mechanically couples the isolating diaphragm to a second diaphragm of a variable capacitor assembly, preferbly one of the center-mounted type where the diaphragm is one plate of the capacitor. The second diaphragm is also edge-mounted and produces a counterforce acting on the side of the isolating diaphragm opposite the side adjacent the fluid. The force of the fluid pressure acting on the isolating diaphragm is transmitted by the drive rod to the second diaphragm where changes in the capacitance correspond to changes in the pressure.
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