| 摘要 |
<p>To monitor the rotation of a disc with normal marks and a reference mark, respective pulses P are produced upon passage of the marks, a first stored value being increased at a steady rate during the spaces between pulses and decreased during the pulses themselves, and a second stored value being increased at a lower steady rate throughout a whole cycle, whereby a comparison of the two stored values at the end of the cycle depends upon the time between the pulses and thus serves to distinguish between the passage of a normal mark and the passage of a reference mark. The stored value may be the charge on a capacitor (C1, C2) or the content of a counter. The disc may be attached to the camshaft of the engine of a motor vehicle and the results of the comparison may be used to determine the point of ignition and the point of fuel injection.</p> |
