Abstract: A method of making a capacitive pressure sensor preferably for a vehicle fuel system with a flexible diaphragm, spacer and rigid substrate disposed in opposed face-to-face relation in a housing and yieldably urged together by a spring clamp. Electrodes disposed on the immediately adjacent opposed faces of the diaphragm and substrate produce a signal indicative of and varying with changes in the pressure of fluid acting on the diaphragm to displace its central portion relative to the substrate. In operation, through sensor and control circuitry, the speed of a fuel pump is varied to vary and control the pressure of fuel supplied to an engine in response to varying engine operating loads and conditions. To control the flow of fuel, a check valve, pressure relief valve and vent valve may be provided in the housing.

Abstract: A capacitive pressure sensor preferably for a vehicle fuel system with a flexible diaphragm, spacer and rigid substrate disposed in opposed face-to-face relation in a housing and yieldably urged together by a spring clamp. Electrodes disposed on the immediately adjacent opposed faces of the diaphragm and substrate produce a signal indicative of and varying with changes in the pressure of fluid acting on the diaphragm to displace its central portion relative to the substrate. In operation, through sensor and control circuitry, the speed of a fuel pump is varied to vary and control the pressure of fuel supplied to an engine in response to varying engine operating loads and conditions. To control the flow of fuel, a check valve, pressure relief valve and vent valve may be provided in the housing.