| 摘要 |
A capacitive pressure sensor (10) includes a conductive diaphragm (20) positioned between two pneumatically separate chambers (60, 64). The diaphragm is supported at its periphery by a concave base member (30). An electrode assembly (40) establishes a substantially planar conductive surface (42a) opposite to, and spaced apart by a nominal gap from, the conductive diaphragm. The electrode assembly includes the conductive surface and a single support element (44) secured to, and extending through the base member. A glass dielectric (46) fixes the support element to a collar (48) which may be welded, brazed, or soldered to the base member. The glass dielectric provides both mechanical support and high quality electric insulation between the electrode and the housing. By prefabricating the electrode support element with the collar and securing the collar to the housing after the dielectric has cured, problems associated with thermal expansion are avoided and the dimension of the nominal gap may be precisely controlled at low cost.
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