Patent ID: 9062621
Filing Date: 2015-06-23
Classification: F02D,Y02T

Abstract:
1. A fuel control method for handheld engine operating machine, in an engine with a carburetor in which a solenoid valve which controls a fuel flow rate during engine operating time and an idle jet which keeps a fuel flow rate to a constant value during an engine idling time are provided in a fuel passage communicating to a carburetor measuring chamber and a throttle valve respectively, the fuel control method comprising steps of: carrying out a rotational speed detecting process of measuring a rotational speed of the engine during engine idling time after the engine is started up; carrying out an idle rotation adjusting process of making a rotational speed detected by the rotational speed detecting process equal to an initial value of rotational speed among initial values determined according to results obtained by previous idle rotation adjusting process at the latest driving time of the engine by controlling an ignition timing while comparing the detected rotational speed with the initial value of rotational speed as target value; and determining an adjusted valve opening (A.V.O.) which is an opening of the solenoid valve during engine operating time determined by a valve opening correction process of making an optimum air-fuel (A/F) ratio during engine operating time which is estimated from an idle ignition timing change (I.I.T.C.) which is a difference from the initial value of the ignition timing among the initial values obtained by the previous idle rotation adjusting process.