METHOD FOR DISCRIMITATING THE STROKE OF SINGLE CYLINDER ENGINE OF FOUR STROKE

摘要

A method for discriminating the stroke of a single-cylinder four-stroke engine mounted with an electronic ignition system and a fuel injecting system is provided to electronically control fuel-injection and ignition time at the right time by discriminating the strokes of the engine with a crank shaft rotation sensor and to repress unburned gas emitted to the air and generated in igniting and injecting the fuel for every 2-stroke. A method for discriminating the stroke of a single-cylinder four-stroke engine mounted with an electronic ignition system(600) and a fuel injecting system(500) is composed of a crank shaft-saw tooth detecting steps for detecting a saw tooth(210) passing a rotation signal generator(300) at first in an initial driving stage of a crank shaft(100); a timer operating step for driving a timer for measuring an effective saw tooth at the same time as the saw tooth detecting step of the crank shaft; an effective saw tooth detecting step for detecting the number of effective saw teeth passing through the rotation signal generator; and a missing tooth detecting step for measuring the rotation time before forming a missing tooth region(220) from a signal detected by the effective saw tooth detecting step. The discriminating method detects the missing tooth of a signal disc plate(200) for the initial rotation, measures the time for every rotation of 180 degrees of the crank shaft till measuring a second missing tooth, and discriminates the stroke by comparing two rotation speeds for every rotation of 180 degrees of the crank shaft.