In automotive vehicles as well as other applications it is necessary to obtain a measurement of air pressure, manifold pressure or some other pressure. Commonly such sensors include a base, a diaphragm movable in response to pressure fluctuations, a sensor element on the diaphragm responsive to diaphragm stress, a compensator circuit for adjusting the output of the sensor element to obtain a pressure signal, a cover to enclose the diaphragm, and terminals extending through some part of the base or cover to supply power to the device and bring out the pressure signal. It is important, especially where the sensor apparatus is produced in high volume, to minimize the cost of the assembly while maintaining high quality.
It is known to mount a pressure sensor or other circuit on a base or housing which also incorporates terminals extending laterally from the circuit or normal to the plane of the circuit but laterally offset from the circuit. However an inline configuration is desired such that outer terminal blades are normal to and aligned with the circuit or diaphragm and they are on the same side of the base as the circuit or diaphragm. Then the base can be connected to the pressure source and the terminals will extend away from the source.
It has been proposed to use a flex circuit that is soldered to a DIP package compensation IC and uses adhesive and gold wire bond to attach to the sensing element. This requires special manufacturing processes and high cost of the flex circuit and packaged ICs. Another proposal uses a pin and socket interconnect. The sensing element is wire bonded to a circuit board that includes the socket portion of the interconnect. The pin, made by extending and forming the terminals on the connector, is manually mated to the socket. Automating this type would be costly and would present potential quality problems.
To maintain high quality and low cost, it is desirable to construct a pressure sensor apparatus which is readily assembled by automated processes and which avoids unnecessary component cost.
USPTO Backgrounds
USPTO Backgrounds