Patent attributes
A pressure sensor (30) for harsh environments such as vehicle tires, formed from a chamber (58) partially defined by a flexible membrane (50), the chamber (58) containing a fluid at a reference pressure. In use, the flexible membrane (50) deflects from any pressure difference between the reference pressure and the fluid pressure. The membrane (50) being at least partially formed from conductive material so that associated circuitry (34) converts the deflection of the flexible membrane (50) into an output signal indicative of the fluid pressure. The flexible membrane is less than 3 microns thick to allow the use of a high yield strength membrane material. A thinner membrane also allows the area of the membrane to be reduced. Reducing the area of the membrane reduces the power consumption and the overall size of the sensor. A high yield strength material is better able to withstand the extreme conditions within the tire and a compact design can be installed in restricted spaces such as the valve stem.
