| 摘要 |
PURPOSE:To measure the amount of strain and the temperature at the same time by utilizing the fact that the temperature coefficient of the bridge impedance is large when a constant voltage is impressed to a bridge circuit of a semiconductor strain gauge. CONSTITUTION:A temperature compensating resistor 6 is connected to a bridge circuit 10 of semiconductor strain gauges 1-4, to which a constant voltage is impressed. At the same time, a contact point of the strain gauges 3, 4 is earthed. When the circuit 10 is attached to a pressure sensitive film or the like and the pressure sensitive film bends in accordance with the fluid pressure, the potential difference of contact points between strain gauges 2, 3 and strain gauges 1, 4 is changed. Therefore, the pressure is detected from the outputs of a strain amount measuring device 12. Since the strain gauges 1-4 are made of semiconductors, the temperature coefficient of the bridge impedance is large, and the output of the circuit 10 is changed corresponding to the change of the temperature. Accordingly, the temperature can be detected by taking the output change by means of a temperature measuring device 13. |
