| 摘要 |
PURPOSE:To take an accurate measurement from a low-speed range to a high- speed range by converting the AC signal of a magnetic sensor into a pulse signal, differentiating this pulse signal by a differentiation circuit, and switching and controlling the cutoff frequency of the differentiation circuit to a proper value. CONSTITUTION:The magnetic sensor 12 detects the passage of a body to be detected magnetically and outputs the AC signal every time it passes. This pulse signal generating circuit 14 is provided with the differentiation circuit 40 and a bidirectional variable resistance circuit 50 and the cutoff frequency of the differentiation circuit 40 is switched and controlled automatically to a proper value according to the frequency of the basic wave of the AC signal. The output of the differentiation circuit 40 is outputted to a pulse generating circuit 80 through a clamping circuit 60 and a low-pass filter 70. The pulse signal from the pulse generating circuit 80 is outputted to a speed arithmetic circuit.
|
