| 摘要 |
PURPOSE:To prevent such an inoperative state of measurement that the output signal of a speedometer stays near zero to be kept from following the flow velocity of powder by providing a first comparison circuit and a circuit means which is controlled to apply a specified voltage signal to an integrated value signal. CONSTITUTION:This apparatus is provided with a circuit means (diode D, resistance R4 or negative potential Vn) which is controlled to add a voltage signal of a specified magnitude to an integrated value signal V0 when the signal V0 is less than the first set voltage V1 with a first comparison circuit 21 and a time limiting circuit 14 adapted to start a delay action of a delay circuit 9 for an upstream signal when a specified time passes after the power source of a correlation type speed indicator is closed. The output signal of the circuit 9 is zero before the power source is closed to the circuit 9 with a circuit 14 even when the power source is closed to the speed indicator while the movement of a moving body is in such a condition as to output a larger detection signal from upstream or downstream detectors 8a and 8b. Thus, the output signal of a multiplication circuit 11 will not be a positive potential thereby by no means disabling the measurement with the speed indicator when the power source is closed. |
