DETECTION CIRCUIT OF DIFFERENTIAL PRESSURE SENSOR

• Main Author: SAKAMOTO YUKIO
• Format: Patent
• Language: English
• Published: 05.04.1994
• Edition: 5
• Subjects: MEASURING; MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER,MECHANICAL EFFICIENCY, OR FLUID PRESSURE; PHYSICS; TESTING

PURPOSE:To adjust the offset of the output of the detection circuit of a differential pressure sensor by a simple adjusting work. CONSTITUTION:A detection circuit is constituted so that pressure detecting bridge circuits 1, 2 containing strain gauges 1a-1d, 2a-2d are respectively provided to two strain generation parts 5A, 5B and the output signals of those two bridge circuits are inputted to a differential amplifier circuit 19 to take the differential pressure signal corresponding to the difference between the pressures acting on the respective bridge circuits. Offset adjusting variable resistor elements 10a-10d of which each one terminal is set to be output terminal of the bridge circuits 1, 2 are provided to two output terminal parts of the bridge circuits 1, 2 and the resistance values of the respective variable resistor elements are adjusted to remove offset contained in the final differential pressure signals. Two variable resistor elements provided to each of the bridge circuits are constituted of a variable resistance element having a large initial resistance value and a large resistance value variable range and a variable resistance element having a relatively small initial resistance value and a small resistance value variable range.