Robin America EH72, Руководство по обслуживанию

Страница: 47 / 74

– 43 –
6. MAGNETO
OPERATION AND FUNCTION
The ignition system is pointless flywheel magneto with automatic advancing characteristic.
Being different from the breaker point type ignition system, this system is completely free from such troubles as
starting-up failure owing to dirty, burnt or corroded point surface.
The electronic automatic advancing ensures extremely easy starts and stable high performance at operating
speed by advancing the ignition timing to the most suitable point.
BASIC THEORY
(1) Revolution of the flywheel generates electricity on the primary side of the ignition coil, and the base current
I
1
flows to the power transistor. Current I
1
turns the power transistor "ON" and the electric current I
2
flows.
Low Speed
Ignition
Timing
Control Circuit
I
3
I
4
Signal Transistor
A
Automatic
Advancing
Control
Circuit
I
5
I
6
Signal Transistor
B
I
1
Resister
I
2
Power Transistor
Secondary Coil
Primary Coil
Spark plug
500 1000 2000 3000 (r.p.m.)
ENGINE REVOLUTION
IGNITION TIMING
STEP ADVANCING
ELECTRONIC ADVANCING FLYWHEEL
MAGNETO SYSTEM
(B.T.D.C.)
Fig. 6-1 (a)
Fig. 6-1 (b)