| 摘要 |
To counteract the phase error in the signal from an rpm transducer of an engine test stand or analyzer at varying engine speeds, the signal processor of the invention receives the transducer signal whose amplitude varies with frequency and generates therefrom an output signal of constant amplitude. This signal is supplied to a threshold switch which includes circuitry for integrating periodic output signals and generating therefrom a control signal whose amplitude is proportional to the frequency of the input signal. This analog signal is used to alter the switching threshold of the threshold switch, thereby imparting to the output signal a frequency compensation which counteracts the inherent phase error and results in an output signal of constant phase with respect to the transducer signal. The apparatus of the invention is particularly useful for adjusting ignition timing, valve timing, etc. in internal combustion engines in which the input signal is derived from the crankshaft speed.
|
