DUTY RATIO MEASURING SYSTEM FOR VARIABLE FREQUENCY PULSES

摘要

In a system for measuring the duration ratio of pulses of variable frequency, particularly in electronically controlled fuel-injection systems for internal-combustion engines, there are derived clock pulses to the frequency of which a predetermined multiple of the frequency of the pulses (input pulses) corresponds. The duration ratio is then determined by counting the clock pulses during each one pulse. For duration ratios of 0% and 100%, corresponding values are delivered independently of the counting.