PRESSURE SENSOR Russian patent published in 2012 - IPC G01L9/04 

FIELD: physics.

SUBSTANCE: pressure sensor has a housing, a diaphragm (1) with radius r₁, having a rigid centre (2) with radius r₂ and a thick peripheral base (3). Tensoresistors (R1-R8) are formed on the diaphragm in form of identical resistive tensoelements connected by low-resistance jumpers in a circular and radial direction. The tensoresistors (R1-R8) are connected in two bridge circuits. One of the bridge circuits lies on the perimetre of the thick peripheral base (3) and the other lies on the perimetre of the rigid centre (2). Tensoresistors (R1, R3) of the first bridge circuit, which are connected in a radial direction, lie opposite tensoresistors (R5, R7) of the second bridge circuit which are connected in a radial direction. Tensoresistors of the first bridge circuit (R2, R4), which are connected in a circular direction, lie opposite tensoresistors (R6, R8) of the second bridge circuit which are connected in a circular direction. The bridge circuits are connected by feed diagonals to common contact pads (4). Output diagonals are connected in anti-parallel manner. The size of the sides of the resistive tensoelements of radial and circular tensoresistors are equal. Through their vertices furthest from the centre of the diaphragm (1), tensoelements of the first bridge circuit touch the boundary surfaces of the diaphragm (1) and the peripheral base (3). Through their vertices furthest from the centre of the diaphragm (1), resistive tensoelements of the second bridge circuit touch the boundary surfaces of the diaphragm (1) and the rigid centre (2). Tensoresistors (R1-R8) are made from the same material in a single process.

EFFECT: high accuracy of measurement in the entire operating temperature range, including under the effect of thermal shock.

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