STARTING SYSTEM Function: Bring the engine to cranking r.p.m. (200rpm) so the engine can draw fuel and air and ignite that fuel and air.

STARTING SYSTEMSTARTING SYSTEM

Function: Bring the engine to Function: Bring the engine to cranking r.p.m. (200rpm) so cranking r.p.m. (200rpm) so the engine can draw fuel and the engine can draw fuel and air and ignite that fuel and air.air and ignite that fuel and air.

Starter Principles VideoStarter Principles Video

Construction (PARTS)Construction (PARTS)

• CasingCasing• Drive housingDrive housing• End capEnd cap• ArmatureArmature• BrushesBrushes• DriveDrive• BushingsBushings• SolenoidSolenoid• Drive forkDrive fork• Return springReturn spring

Construction VideoConstruction Video

Parts Pole shoe typeParts Pole shoe type

• Four pole shoesFour pole shoes• Four field windingsFour field windings• Fords movable pole shoeFords movable pole shoe

– One pole shoe is moveableOne pole shoe is moveable– Contact discContact disc– Return springReturn spring– PlungerPlunger

Pole shoe VideoPole shoe Video

SOLENOIDSSOLENOIDS

• Types:Types:– Positive engagementPositive engagement– Solenoid ActuatedSolenoid Actuated

• Function: Function: • Engage starter drive*Engage starter drive*• Supply current to starterSupply current to starter• Disengage the current and driveDisengage the current and drive

**not on moveable pole shoe typenot on moveable pole shoe type

ConstructionConstruction

• Pull in windings(large)Pull in windings(large)• Hold in windingsHold in windings• PlungerPlunger• Return springReturn spring• Contact discContact disc

Solenoid VideoSolenoid Video

Wind typesWind types

• SeriesSeries• Shunt (parallel)Shunt (parallel)• Compound (series/parallel)Compound (series/parallel)

Starter drivesStarter drives

• Function:Function:– Provide for a positive engagement Provide for a positive engagement

with the ring gear.with the ring gear.– Protect the armature from prolonged Protect the armature from prolonged

engagement.engagement.

Starter Drive VideoStarter Drive Video

Starter Armature Starter Armature

• Function: Is the moving part of a Function: Is the moving part of a starter motor. The armature uses starter motor. The armature uses an EMF to push and pull itself an EMF to push and pull itself

CommutatorCommutator

Purpose: The commutator is on the Purpose: The commutator is on the armature, it is used to switch the armature, it is used to switch the current paths though the armature current paths though the armature windings so that the armature windings so that the armature always bends the “Lines of Flux” always bends the “Lines of Flux” (carrot in front of the donkey)(carrot in front of the donkey)

CommutationCommutation