4ELECTRONIC Ignition System | Subaru Robin Power Products R1300

5-4ELECTRONIC IGNITION SYSTEM

The electronic ignition system features a power transistor as the current control element. Therefore, the ignition system is an electronic contact point-free type that operates with the power transistor impulses 4 controlling the current. This system is also called TIC (transistor igniter circuit) and is virtually free of ignition failure which generally results from contamination of the contact points, a typical problem with contact type ignition systems.

Becausethis ignition systemhas no contact points, it is not affected by moisture, oil, dust, or other contaminants. As a result, this electronic ignition system ensures sure and positive ignition with reduced maintenance.

The TIC mechanism consists of a transistor-incorporated ignition coil and a permanent magneto built-in flywheel which is press-fitted on the rotor shaft of the generator.

Fig. 5-9

(1)When the permanent magneto built-in flywheel start rotating, power is generated in the primary coil of the ignition coil and current flows to theresistor @ .

From the resistor, current flows the power transistor. With this current, the power transistor turns on, releasing current a.This stagecorresponds to theclosing of contact points.

(2)As the flywheel comes to thepoint of ignition, timing detecting circuit is activated while the current

@is flowing through the circuit.

When the ignition timing detecting circuit is activated, the signal transmitter transistor actuates with current @ flowing. When current@ starts flowing,current @ flowing through the power transistor is cut quickly. As a result, high voltage is produced in the secondary coil and this voltage is applied simultaneously to the spark plug which ignites forignition. This stagecorresponds to the opening of contact points.

- 11 -