| 摘要 |
PURPOSE:To achieve a higher vibration-proof characteristic, by providing a judgement function to determine whether an output signal is a vortex signal or not by amplitude of a frequency. CONSTITUTION:A vortex signal from a stress detection sensor 1 is converted with a charge converter 11 into a voltage signal E11. One of resulting signals is applied to a Schmitt trigger circuit as input E13 via a filter circuit 12 and a first amplification circuit 13. When an input frequency of a circuit 14 is larger than a trigger level set, it is outputted as pulse signal P14. The other thus converted is turned with a rectification circuit 22 to a DC voltage signal E22 through a second amplification circuit 21. This signal E22 is compared with an output voltage E23 of an F/V converter 23 into which the signal P14 is input ted by a comparator 24. When the signal E22 is larger than the voltage E23, an output of the comparator 24 turns ON a switch of a gate circuit 15. When the switch of the circuit 15 is ON, the signal P14 is outputted as vortex fre quency signal while the signal P14 is cut off as noise when the switch thereof 15 is OFF. |
