| 摘要 |
A method of and an apparatus for converting a first series of pulses into a second series of pulses having a frequency proportional to the frequency of the first series. The method and apparatus are particularly useful for providing a series of equally spaced pulses representative of the speed of a rotating gear in revolutions per minute (RPM). A proximity detector provides a pulse as each tooth of the gear traverses the face of the proximity detector and a sample period is formed by the passing of several teeth. A series of pulses is counted by a counter for the length of the sample period. The number of pulses at the end of the sample period is stored in a latch. A programmed divider counts down from the count in the latch to zero at a reference frequency and an output pulse is provided each time the programmed divider reaches zero. The programmed divider is reset to the count in the latch upon the occurrence of each output pulse. In a specific application, the number of output pulses from the counter is made equal to the number of pulses that would be generated by a gear having sixty teeth and rotating at the same speed for convenient display of RPM on a digital counter with a one-second time base.
|
