Control apparatus for general-purpose internal combustion engine

A control apparatus for a general-purpose internal combustion engine having an output shaft connected via a centrifugal clutch to a load device, the control apparatus comprising a manual starter, a carburetor having a throttle valve for opening and closing an intake passage, and a stepping motor for controlling opening and closing of the throttle valve, in which the internal combustion engine is started from a full-open position of the throttle valve and, after the start of the engine, the stepping motor is activated so as to close the throttle valve from the full-open position, wherein

• the control apparatus further comprises:
• a generator as a power supply of the engine, the generator including a main generator coil for supplying power to the stepping motor, and an auxiliary generator coil for supplying power to an ignition device of the engine, the auxiliary generator coil being a separate coil from the main generator coil;
• and
• ignition timing control means for, when starting the engine by the manual starter, detecting that an engine speed of the engine is equal to or more than a predetermined engine speed which is equal to or less than a connecting rotation speed of the centrifugal clutch, and retarding an ignition timing of the engine so as to suppress increase in the engine speed of the engine to less than the connecting rotation speed of the centrifugal clutch, and also for restoring the ignition timing to its normal timing after a lapse of a predetermined time from start of retarding the ignition timing,
• wherein the control apparatus further comprises an electronic control unit configured to receive the power from the main generator coil to control the stepping motor, and
• after the lapse of the predetermined time from the start of retarding the ignition timing, an output voltage from the main generator coil rises sufficiently to place the electronic control unit in an operating state to control the stepping motor.