Method and apparatus for adjusting fuel injection timing.

摘要

A method and apparatus for improving the output torque response of a crankcase scavenged, two-stroke engine 10 to a change in throttle position TP by adjusting the conventional timing of cylinder fuel injection FIT as a function of the position of the throttle 22 and the time rate of change in the throttle position TPF. Preferably, throttle position TP is measured with a potentiometer 44 connected to the engine air intake throttle 22, and then filtered with a filter 56 having a first order lag characteristic. Injection timing FIT is advanced based upon a first predetermined schedule as a function of the measured throttle position TP. The difference DIFF between the measured and filtered throttle positions represents an indication of the time rate of change of throttle position and is employed to advance or retard timing in accordance with the second predetermined schedule, depending upon whether the difference is positive or negative, respectively. As a result, a substantially linear relationship is established between the output torque of the engine 10 and the position of the throttle 22 over its entire range of movement, and the amount of time required for the engine 10 to respond to abrupt changes in throttle is reduced.