mechanical arrangement piston engines the main bits and pieces that make up the piston engine

Mechanical ArrangementMechanical Arrangement

Piston EnginesPiston Engines

The main bits and pieces that make up the piston engineThe main bits and pieces that make up the piston engine

Mechanical Arrangement - BasicsMechanical Arrangement - Basics

Mechanical Arrangement - BasicsMechanical Arrangement - Basics

A

B

Hand force in direction ‘A’ gives rotational

force on nut

Leg force in direction ‘B’ gives rotational

force on pedal/crank propels bicycle along

Mechanical Arrangement - BasicsMechanical Arrangement - Basics

Cylinder

Piston

Connecting Rod

Crank Shaft

‘Big-end’

Gudgeon Pin Main

Bearings

Offset Bearing

Counter Balance Weight

Mechanical Arrangement - BasicsMechanical Arrangement - Basics

11

2233

44Pistons

Crankshaft

Rear

Front

Flywheel attachment

flange

Timing Belt and Water Pump

driving pulley location

Main Bearings

Mechanical Arrangement – Main PartsMechanical Arrangement – Main Parts

Sump (Oil Tank)

‘Rocker Box’ Cover

Cylinder Block

Flywheel

Valve Gear

Crankshaft and Pistons

Exploded View of the Engine

Cylinder Head Assembly

Timing Shaft

Mechanical Arrangement – Valve GearMechanical Arrangement – Valve Gear

Valve Operation

The Inlet Valve needs to be open to allow fuel/air mixture

in

The Exhaust Valve needs to be open to allow burnt gases

out

Inlet Valve Exhaust Valve

Mechanical Arrangement – Valve GearMechanical Arrangement – Valve Gear

Rocker

Rocker Shaft

Closing spring

Valve Seat

Push Rod

Cam Shaft

Inlet Valve Closed Inlet Valve Open

Valve Lift

Push Rod Mechanism

Overhead Cam -No Rocker

Overhead Cam and Rocker Push Rod

Mechanism

Mechanical Arrangement – Valve GearMechanical Arrangement – Valve Gear

Mechanical Arrangement – Valve GearMechanical Arrangement – Valve Gear

Modern Engines use a toothed rubber belt to drive the cam shafts

Cam Drive Mechanism

Crankshaft and

Pistons

Twin Cam System

Chain Tensioners

Put it all together

Mechanical ArrangementMechanical Arrangement

How does it work?