| 摘要 |
PURPOSE:To enable to measure the rotating speed to nearly zero rotation from a low speed rotation by providing two sampling circuits. CONSTITUTION:The first counter for counting a pulse proportional to the rotating speed and the second counter for measuring the pulse interval are provided, the value of the first counter is divided by the value of the second counter to calculate the rotating speed. In this case, as shown in Fig. (a), it is immediately calculated by the next pulse after the first sampling time Ts is finished for the first sampling. Further, when next pulse does not exist, (e.g., low speed time), as shown in Fig. (b), the rotating speed is calculated immediately when the second sampling time Tl is finished for the second sampling. |
