Abstract: In an engine which starts using a recoil starter, ignition chance during inertia rotation is not missed. If the engine 42 is rotated by the recoil starter 41, output of a power generator which is directly connected to the engine 42 is increased, and a CPU 27 is reset at timing t0. At timing t1, if pulse P1 is input from a revolution number sensor 29 to the CPU 27, the CPU 27 outputs first ignition instructions when predetermined time T1 is elapsed (t2). At timing t3, second pulse P2 is input. At that time point, since the CPU 27 is normally operated, ignition timing is obtained from an ignition timing map 30 in accordance with the revolution number calculated by a time interval between the pulses P1 and P2, and the ignition instructions are output at timing t4 in accordance with the ignition timing. Thereafter, the ignition timing is determined using the ignition timing map 30.

Abstract: In an engine of a working machine having no governor mechanism, the engine revolution speed is controlled such that the revolution speed can stably be maintained irrespective of the variation in load without adjusting the throttle opening to exploit the full potential of the engine. Since an engine 1 does not have the governor mechanism, an operator adjusts the throttle opening and controls the engine revolution speed. A map in which ignition timing (amount of angle of lead) is set by means of functions of the engine revolution speed is stored in an ignition timing map 30. The map 30 is set such that the engine revolution speed is equal to or higher than a value to be controlled (e.g. 7000 rpm), and the ignition timing is lagged as compared with a case in which the engine revolution speed is lower than the value to be controlled.

Abstract: In an engine of a working machine having no governor mechanism, the engine revolution speed is controlled such that the revolution speed can stably be maintained irrespective of the variation in load without adjusting the throttle opening to exploit the full potential of the engine. Since an engine 1 does not have the governor mechanism, an operator adjusts the throttle opening and controls the engine revolution speed. A map in which ignition timing (amount of angle of lead) is set by means of functions of the engine revolution speed is stored in an ignition timing map 30. The map 30 is set such that the engine revolution speed is equal to or higher than a value to be controlled (e.g. 7000 rpm), and the ignition timing is lagged as compared with a case in which the engine revolution speed is lower than the value to be controlled.

Abstract: In an engine which starts using a recoil starter, ignition chance during inertia rotation is not missed. If the engine 42 is rotated by the recoil starter 41, output of a power generator which is directly connected to the engine 42 is increased, and a CPU 27 is reset at timing t0. At timing t1, if pulse P1 is input from a revolution number sensor 29 to the CPU 27, the CPU 27 outputs first ignition instructions when predetermined time T1 is elapsed (t2). At timing t3, second pulse P2 is input. At that time point, since the CPU 27 is normally operated, ignition timing is obtained from an ignition timing map 30 in accordance with the revolution number calculated by a time interval between the pulses P1 and P2, and the ignition instructions are output at timing t4 in accordance with the ignition timing. Thereafter, the ignition timing is determined using the ignition timing map 30.