Transcript Ignition Systems

Objectives

Understand the function of small engine
ignition systems
Electricity


Electricity is important to
the ignition system for
igniting the spark
Terms
 Electricity: Movement of
electrons from one atom to
another
 Conductor: Any material
that allows good electron
flow and conducts
electricity
○ Ex: Copper wire
 Insulator: material to keep
the electricity from
escaping the conductor
○ Ex: Plastic wire coating
Electricity
Circuit: Path that allows
electrical current flow
 Ground Circuit: allows
wires to make a
complete circuit

Magnetism and Induction
Used to generate
electricity in the magneto
 Magnets are attached to
the flywheel for this
purpose
 Magnets are attached
using adhesive, screws
or recessed in the
flywheel

Magnetism
Induction


Transfer of electricity
from one conductor to
another without touching.
This is used in the
magneto coils to charge
one another
The magneto: 2 Parts
Armature


Thin metal strips that
receive the magnetic
energy
Come in 2 leg and three
leg varieties
 2 leg is common in small
engines
Coil

Set of 2 copper wire coils
 Primary and Secondary
Winding

Primary Winding
 Is provided low voltage
electricity form the magnets

Secondary winding
 Develops High voltage
though induction of primary
winding
 This winding is what
produced the electricity for
the spark plug
Breaker points
Used to trigger the primary
circuit mechanically
 Usually mounted below
flywheel

 Small metal contacts
Usually used in older
engine models
 More modern engines use
a Electronic Trigger system

 In our engines we use the
magnetron