Magnetic ignition system for motor-driven chain saws

摘要

The invention relates to a magnetic ignition system for a small spark-ignition motor, in particular for the motor of a chain saw. A magnet wheel 1 with a permanent magnet rotating with the crankshaft 2 of the motor runs past a charging armature 16 with a charging coil 15 and induces a voltage which is fed to an energy store 12. At the time of ignition, the energy store is discharged by a pulse from an igniter 5 via the primary winding 11 of an ignition transformer 10 whose secondary winding 9 is connected to the spark plug 8. In order to provide sufficient ignition energy even at low speeds, provision is made according to the invention for the permanent magnet of the magnet wheel 1 to be located opposite the charging armature 16 in a position of the crank shaft between about 80 DEG KW after OT up to about 80 DEG KW before OT. <IMAGE>