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INTRODUCTION TO I.C.E
Session 1 Course Introduction
Taught byChris Coles
Teacher IntroductionHealth & Safety,Risk AssessmentsGround RulesClass IntroductionsIce BreakerVARK Questionnaire
Aim
Build Basic Knowledge of
Internal Combustion Engines (I.C.E)
INTRODUCTION TO I.C.E
Session 4 Engine Components
Taught byChris Coles
Module Objectives
Present the:
Piston and Combustion Chamber. Engine Arrangements and Cylinder Configuration. Con-rod and Crankshaft. Intake and exhaust valves. Cam-shaft and configuration SOHC, DOHC. Auxiliary Gearing or Belt Drives.
Demonstrate and discuss the interaction of components of an I.C.E.
Combustion Chamber Cylindrical in shape known
as a Cylinder.
Pressurised Chamber.
Made for Combustion.
Directs Explosive Force to Piston.
Piston Head Fits inside Combustion
Chamber.
Explosive force acts on the Piston Head.
Produces LINEAR movement.
Friction creates heat.
Oil cooling by Scraper Rings.
Cylinder Configuration Straight (also known as Inline engines).
Single Bank of Cylinders.
Cylinder Configuration V Type (V6, V8, V12)
Two Banks of Cylinders < 180º
Cylinder Configuration O Type (Opposed Cylinders)
Two Banks of Cylinders = 180º
Cylinder Configuration W Type (W12)
Three Banks of Cylinders 90º
Cylinder Configuration
Straight V O
Cylinder Configuration Other less popular variations:
X – 4 Banks of Cylinders (1 Crankshaft). H – 4 Banks of Cylinders (2 Crankshaft). U – 2 Banks of Cylinders (2 Crankshaft).
Deltic – 3 Banks (Triangular Shape). Star – 5 or more banks.
Movement LINEAR movement (Piston).
ROTATIONAL movement (Wheel).
Crank Shaft Pistons connect to
the Crankshaft.
Explosive force of combustion pushes the Piston downwards (LINEAR).
Offset pins transferlinear force torotational force.
Crank Shaft A 2nd Explosion on a different
offset pin will push that pin down.
Causing the Crankshaft to turn, and the 1st piston to rise back up the Cylinder.
Con Rod Piston Head connects to the
Con Rod by Gudgeon Pin.
Con Rod connects to Crankshaft in a bearing.
White metal bearing is 2x ‘U shapes’ tightened by bolts.
Con Rod Piston Head to the Con Rod by Gudgeon Pin. Con
Rod connects to Crankshaft.
Transmits force from Piston to Crank.
Intake Valves When OPEN provide the cylinder with a fresh
charge of air for compression.
When CLOSED creates a pressurised chamber forcompression.
Exhaust Valves When OPEN purges exhaust gas from the cylinder
to the exhaust system.
When CLOSED creates a pressurised chamber forcompression.
ValvesWhat prevents the valves from staying open and always ensures they are closed?
Valves Stem & SpringA Spring ensures the valve remains:CLOSEDuntil something pushes down on the Stem Top.
Cam Shaft A Cam Shaft is a single shaft
with egg shaped Cams fitted.
The Cams apply pressure at different intervals to different valves.
So Cylinder 1 may be on an exhaust stroke whilst Cylinder 2 may be on a intake stroke.
SOHC Cam ShaftA Single Overhead Camshaft (SOHC).on a Straight 4 Cylinder Engine.
DOHC Cam ShaftA Double Overhead Camshaft (DOHC).may be used on a V Type Engine or may just operate different Valves.
Incorrect Cam Timing If the valves do not operate at the correct time,
the chamber will not be pressurised.
The spark would not ignite the gas if there was no pressurised fuel/air mix.
Without an explosion, thePiston will not be forceddownwards.
The Crankshaft has no linearmovement to convert to rotation.
Water and Fuel PumpsA water pump cools the engine block due to the incredibly hot temperatures of the cylinder combustion chambers and valves.How is the water pump powered/driven?
Belt Drives A non-slipping mechanical belt driven by the
Crankshaft.
Made of durable rubber.
Known in cars as Timing Belts.
Speed increased by increasing engine speed; therefore more power created, more heat is generated, so more coolant cools the engine block.
Auxiliary Gears Same purpose as a timing belt but replaces a belt
with grooved teeth gears.
Often found in larger engines due to cost.
No requirement for timing belt changewhen purchasing a 2nd hand car.
Cam Shaft When the piston is at Top Dead Centre (highest
point)
If either valve was open, a collision with the piston could bend the valves.
Therefore the valves must be timed with the piston.
How is this achieved?
Timing Belt Belt Drive Timing Belt Cam Belt Auxiliary Gears
Can drive the following auxiliaries:
CamShaft (SOHC) or both CamShafts (DOHC)
Water Pump
Oil Pump and Fuel Pump
Flywheel A rotating mechanical device weight.
Resists sudden changes in speed by storing rotational movement (kinetic energy).
A car going down a hill; will slowly speed up as the fly wheel prevents the engine over speeding.The fuel is then decreased.
Same principle applies going up hill, the flywheel weight will still turn the engine until the driver has caught up (until the flywheel stored energy runs out)
Atomised Fuel InjectorSUCK, SQUEEZE, BANG, BLOW!
Intake Stroke, Compression Stroke, Combustion Power Stroke, Exhaust Stroke.
The Fuel Spray Head injects fuel at the compression stroke.
Fuel mixes with the high pressure compressed air.
The fuel/air mix is then ignited by a spark.
Spark Plugs
A Spark Plug creates a spark (arcing across 2 contacts) for a combustion explosion
Will operate only at the point where all air is fullycompressed and fuel is mixed.
Require very high voltages25,000 – 60,000volts.
The current is very small.(static shocks are 1,000 – 23,000).
Combustion / Power
The spark ignites the fuel injected which has mixed with the compressed air in the pressure tight cylinder.
The explosion generated causes force on the Piston Head downwards creating linear movement.
This rotates the Crankshaft and the exhaust valve opens. As the Crankshaft rotatesthe piston will rise back up purging the exhaust gases.
Video / Demonstration
Any Questions?
Build Basic Knowledge of
Internal Combustion Engines (I.C.E)
Session 4 – Basic Components of an Engine
Summary
Objectives Covered:
Piston and Combustion Chamber. Engine Arrangements and Cylinder Configuration. Con-rod and Crankshaft. Intake and exhaust valves. Cam-shaft and configuration SOHC, DOHC. Auxiliary Gearing or Belt Drives. Interaction of all Components.
Module Learning Objective:“Students understand the basic components of a
modern engine and there interaction”.
