| 摘要 |
<p>PURPOSE:To eliminate a harmful influence caused by unnecessary secondary vibrations associated with vibrations produced in a granule detector so that the measuring accuracy of the detector can be improved by outputting signals only when the rise of the vibrations is detected. CONSTITUTION:Signals SI outputted from the granule detector 1 in accordance with the detection of granules are outputted and subjected filtration and half- wave rectification 2 and become signals S2. The signals S2 are compared 3 with a 1st reference value supplied from a clip circuit 4 and, as a result, a programmable uni-junction transistor 5 which is a switching element is turned on at the rising time of the signals S2. Then a PUT 5 is turned off after the capacitor C1 of a charge and discharge circuit 5 is quickly charged. The output signal S4 of the circuit 5 is compared 6 with a 2nd reference value decided by resistances R2 and R3 and, at the same time, superimposed upon the 1st reference value. Since an output signal S5 which detects the rise of vibrations produced in the detector 1 only is obtained from a comparator 6, the influence of secondary vibrations associated with the vibrations can be eliminated and the measuring accuracy of the detector 1 can be improved.</p> |
