automotive engineering- how cars work
TRANSCRIPT
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AUTOMOTIVE BASICS
Victorious Ma
Engineering| www.CarEager.com
Scan to dfree and
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WHATS IN PRESENTATION
1. Car body contr!ction
". En#ine
$. %!el S!pply in Petrol & 'ieel En#ine (. En#ine related yte)
*. 'ri+e Train
,. S!penion & teerin#
-. %or afety
. E)iion
/. Electrical & H0AC yte)Bumper
Bonnet
Windshield
Fro
Sun!oo"
#rille
Fender
A Pillar
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1. CAR BODY CONSTRUCTIO
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1. CAR O'2 CONSTR3CTION
Two main ways of automobile construction
1. Chassis and Body method (or Body-on-frame)
2. Monocoque method.
1. In the Chassis method the body is made as a searate unit and then !oined with ladder tye structu
chassis. #ll other arts li"e steerin$% susension etc. are attached to the chassis.
The benefit of chassis construction is hi$her load caacity and stren$th. But the body tends to &ibrat
&ehicle handlin$ and refinement is lower. Thus this alication is used mostly for *+s and bi$$er
2. ,ere% the ladder frame is absent and the comonents li"e the susension% steerin$ etc. are all bolte
body% the body is thus made sturdier.The ad&anta$es here are that the full car is now more solid andsquea"s are not easily de&eloed. ,andlin$ is also better due to the hi$her body ri$idity.
nly ma!or drawbac" is the load carryin$ caacity is lower. or assen$er cars this is not a ma!or co
modern rocess Monocoque bodies are able to handle more loads.
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&' E(#I(ES
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Inline
#ll the cylinders of the en$ine are arran$ed in a strai$ht line.
*-/n$ine
The cylinders are arran$ed in two bloc"s%
connected to the same cran"shaft.
lat 3 ,ori4ontally osed
The cylinders are arran$ed in two bloc"s
connected to the same cran"shaft and which
are hori4ontally oosed (flat).
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)stStro*e + B$C to T$C+ uction ' Comression
#s the iston mo&es uwards % air3fuel mi5ture enters the
cran"case throu$h the inlet ort.
#t the same time air3fuel mi5ture is comressed in the
combustion chamber and i$nited by sar" lu$.
&ndStro*e + T$C to B$C6 7ower ' e5haust
#s the air3fuel mi5ture $ets i$nited% combustion ta"es lace
which $i&es ower and as a result the iston mo&es
downwards and is called ower stro"e.
#t the same time % Inlet ort $ets closed and the air3fuel
mi5ture in the cran"case is comressed and is forced in
to the combustion chamber throu$h transfer ort. which
in turn ut the e5haust $ases out of combustion chamber
and fills the chamber with a new char$e.
Those /n$ines which $i&es the ower at e&ery second stro"e of the iston
T8 T9:/ /0I0/
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EXHAUST
PORT
INLETPORT
I0T#:/ '
CM79/I0
EXHAUSTFRESH
AIR
C#*/0I0 '
/;,#TCMBTI0
SPARK PLUG
T8 T9:/ /0I0/ C
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ese /n$ines $i&es one ower stro"e in e&ery two re&olutions of cran"shaft. our stro"es of the en$ine are
) Inta*e
The 7iston mo&es
downwards from T>C to B>C ta"in$ the air fuel mi5ture inside the cylinder throu$h inlet &al&e.
In this condition inlet &al&e remains oen and e5haust*al&e remains closed
& Compression
The 7iston mo&es uwards from B>C to T>C comressin$ the air fuel mi5ture. In this condition both inlet and
e5haust &al&es remains closed
#s and when the iston
near the T>C% sar" lu$ i$nites. #s a result combustion ta"es lace
- Power
In this stro"e % due to combustion the 7iston
Mo&es downwards from T$C to B$C $i&in$ the ower to the cran"shaft
In this condition both inlet and e5haust &al&es remains closed.
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10/45Two tro"e /n$ines *s. our tro"e /n$ines
Two Stro*e En%ines Four Stro*e En%ines
1 It $i&es ower in e&ery re&olution ofcran"shaft
It $i&es ower in e&ery two re&olutiocran"shaft
2 *al&e less construction % due to which it isli$hter and cheaer
It is ha&in$ &al&es in he construction comared to 2 stro"e en$ines
? ess &olumetric efficiency More *olumetric efficiency
@ Coolin$ is difficult so it may result ino&erheatin$
Coolin$ of the en$ine is easier
A ubrication system is simler ubrication system is comle5
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1. Torque
Is the turnin$ force3effort required to turn or twist any ob!ect
Torque orce 5 9adial >istance
2. /n$ine Torque
Is the turnin$ or twistin$ force de&eloed byen$ine at the cran"shaft
#s the en$ine runs it de&elos some amount of torque(turnin$ force)% which &aries with the rm.
# hi$h torque at low rm will $i&e the &ehicle $ood ullin$ower% and easy dri&ability.
?. /n$ine 7ower7ower is a measure of how quic"ly wor" can be done (mo&in$ the car)
7ower of the en$ine deends on its torque and en$ine seed (97M). More the torque andmore the rm% $reater is the ower
Bra"e ,orse 7ower (B,7) is the B
measurin$ ower% de&eloed by a
7ower (B,7) of the en$ine deen
en$ine seed (97M)
B,7 I,7 6 ,7
(I,7 6 Indicated ,.7 ' ,7 6 ri
7 is a erman term for Metric ,
different unit of measurement of
the en$ine.
1 Metric h 1 7 .DEF bh
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-' FUE2 I(TA1E
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/ I0T#:/6 7/T9 /0I0/
1. Carburetor7etrol and air is mi5ed in the Carburetor
and then sent to combustion chamber.
Main functions are =
1) To &aori4e the fuel to $et a
homo$eneous air fuel mi5ture
2) To suly correct amount of air
fuel mi5ture at different conditions
?) To "ee small reser&e of fuel at constant le&el in the float le&el
$isadvanta%e+ It becomes difficult to ensure
uniformity of Mi5ture quantity in multi cylinders.
T4ere are two type of f!el inta5e yte)61. Carb!retor". %!el In7ection Car4uretor "un,tionin%
#ir3fuel mi5ture is controlled by the combined wor"in$ of
a) *enturi system
b) Main !et% slow !et ' starter !et
c) The butterfly &al&e ( #ccelerator edal)
*enturi system6 #s the air flows throu$h this &enturi. # ne$ati&e
(&accum) de&elos in the assa$e due to which fuel rises from the
mi5 u with the mo&in$ air formin$ a homo$eneous air3fuel mi5tu
The suly of fuel is6
#t Idlecondition 6 uel comes from the Slow 5et.
#t !unnin%condition 6 uel comes from the main 5et
#t Startin% condition 6 uel comes from Starter 5et'
Butterfly &al&e6 It controls the quantity of air $oin$ in to the com
accordin$ly fuel suly also &aries in quantity. T
throu$h accelerator edal.
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T7
M#7
I#T *
Combustion
chamber
/CM
/CT
C:73CM7 2
Throttle body
e
)6 VSS 6 It $i&es the information about the &ehicle seed
&6 C1P7CMP 6 It $i&es the information about the iston of the iston and the stro"e
-6 MAF 6 It $i&es the information about mass air flow enterin$ the throttle body
.6 MAP - It $i&es the information about inta"e Manifold air ressure
86 O&sensor +It senses the o5y$en le&el in the e5haust manifold% accordin$ly /CM decides monitors
the roortion of air-fuel $oin$ to the combustion chamber.
96 IAT It sends the Intake air temperature in! and a""!rdin#$% E&' m!nit!rs the A(F rati!
7) TPS Thr!tt$e p!siti!n sens!r #i)es in!rmati!n a*!ut the p!siti!n ! thr!tt$e +a""e$erati!n,
8) ECT it #i)es the in!rmati!n a*!ut the en#ine "!!$ant temperature +en#ine temperature,
In!ection #ctuators
#t inta"e manifolds
Fue$
Air r!m air i$ter
Fue$ rai$
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2) uel In!ection system -In these en$ines% 7etrol in atomi4ed form is srayed
earately in to the inta"e air% $i&in$ a homo$enous
#ir fuel mi5ture which burns more efficiently in
Combustion chamber.
uel in!ection is of two tyes 6
1) >irect in!ection= In this fuel is srayed directly into
the combustion chamber
2) Multi oint fuel in!ection= In this fuel is in!ected in to
each inta"e ort of the manifold
imultaneous in!ection6In this system all the in!ectors in!ec
simultaneously into the inta"e Ma
rou sequential In!ectionIn!ectors in!ect fuel for a $rou of
2 cylinders at a time in a sequential
equential M7I 6one in!ector in!ects fuel for one cyl
in!ectors are timed to release fuel e
it is needed
Multi oint fuel in!ection 6
In this system there is searate in!ector for each cylinder mounted in the inlet ort.In!ectors directs the fuel in to the inta"e manifold $i&in$ imro&ed mi5ture rearation
and distribution.
Based on the timin$ of fuel in!ection M7I is classified in followin$ three tyes 6
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CO(T!O2 S3STEM OF MPFI
MPFI s:stem is ,ontrolled 4: a devi,e ,alledECM + En%ine ,ontrol module
IAT
'AP
TPS
E&T
&'P
&KP
O-s
.SS
In/e"t!rs
I#niter
E.AP
EGR
Fue$ pump
Radiat!r an
IA&
Sensors A,tuators
'AF
Kn!"k
ENGINE CONTROL MODULE
(ECM/ECU)
T!ta$ 0 12 Sens!rs
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I#(ITIO( S3STEM
#ll 7etrol cars require an i$nition system to suly current to the sar" lu$.
Two main comonents of the system are the i$nition coil and the distributor.
$istri4utor Assem4l:
Spark Plug
I%nition Coil
Current
The function of the i$nitio
battery &olta$e to a &ery hi
sar" to i$nite the fuel.
n most cars one coil is us
all the sar" lu$s.
The function of the distribu
current from the i$nition c
the correct time.
Mostly the distributor is a
has an arm that rotates and
>>I- >ual distributor less i$nition system (#d&anced *ersion)
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/ I0T#:/6 >I// /0I0/
>iesel3Comression i$nition /n$ines are of two tyes -
Indirect In!ection 6
In this system % fuel is in!ected in 7re combustion chamber where the fuel and air
mi5es comletely and then the mi5ture $oes to main combustion chamber
where actual combustion ta"es lace.
6 >irect In!ection
In this system % the fuel is in!ected directly in to
the combustion chamber.
,i h
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,i$h ressure um
Ele,tri, "eed
pump
uelfilter
Fuel Pressure
!e%ulator9
res
sen
/leo
Water in "uel
sensor
"uel temp sensor
/ 77< CM70/0T
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Petrol En%ine ;SI6 Vs' $iesel En%ine ;CI6
S'(o Petrol En%ine ;S'I6 $iesel En%ine ;C'I6
1 Mi5ture of #ir ' 7etrol is drawn into the Cylinder andcomressed
nly air is comressed
2 Comression ratio 6
D=1 to 11=1 (min. to ma5.)
Comression ratio 61A=1 to 2@=1 reshi$her thermal efficiency ' low fue
? ess noisy and runs smoothly Most of the en$ines are noisy com
@ ow *olumetric efficiency ,i$h *olumetric efficiency resultin$economy
A 7etrol is costly and more &olatile >iesel is cheaer and less &olatile
F Initial cost of en$ine is low Initial cost of /n$ine is hi$h due to
construction
H ower combustion efficiency ,i$her combustion efficiency
E 0o heater lu$s required for cold startin$ ,eater lu$s required for colds start
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.' E(#I(E !E2ATE$ S3STEMS
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.' E(#I(E !E2ATE$ S3STEMS
2u4ri,ation S:stem
in functions of ubricatin$ oil is
redu,e wear and tearof the /n$ine arts.
her functions 6
Cleanin%- >urin$ its circulation % it dissol&es
many imurities li"e carbon articles.
Coolin% - >urin$ circulation % it ta"es heat from
the hot en$ine arts and deli&ers it to the
surroundin$ throu$h cran"case .
Cushionin%6 il layer can also ser&e as a cushion
a$ainst the shoc"s '&ibrations roduced by the
/n$ine arts.
Sealin% - ubricatin$ oil also hels the iston rin$
to maintain an effecti&e seal a$ainst the hi$h ressure
$ases in the combustion chamber.
Coolin% S:stem
The 7urose of coolin$ system is to "ee the
/n$ine at its most efficient oeratin$ temer
#t all seeds and under all oeratin$ conditi
ome of the heat is absorbed by the cylinder
8alls% head and istons. They in turn must
Be ro&ided by some means of coolin$ so
That they will not $et too hot.
Tyes of coolin$ systems 6
1) #ir cooled
2) 8ater cooled
In Most of the #utomobile cars% water coolin
ystem is used.
Comressor
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Turbo-char$er
It is a de&ice used to increase the *olumetric efficiency '
therefore /n$ine ower by deli&erin$ ressuri4ed air to the
Inta"e.
/5haust $ases mo&e the turbine which is fitted in the
turbochar$er.
Turbine in turn rotates the comressor rotor % which is
connected to the turbine by a shaft.
Comressor suc"s the resh air comin$ from the air filter.
This ressuri4ed air is sent to Inta"e manifold.
8aste ate *al&e re&ents the turbochar$er from
o&erchar$in$ the en$ine. as and when the air ressure in
the inta"e becomes too hi$h% the waste $ate &al&e oens and
as a result some ercenta$e of e5haust $ases are sent
to e5haust line by assin$ the Turbochar$er.
Inta"e
Comressor
Turb
ine
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8' $!IVE T!AI(
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8' $!IVE T!AI(
lutch -
Clutch is laced between /n$ine ' ear bo5.
Clutch Transmits 7ower from /n$ine to ear Bo5.
It disconnects the ower from en$ine to $ear bo5
for smooth $ear shiftin$ oeration ' to sto the &ehicle.
all the MI roducts >iahra$m tye of clutch
used.
Transmission system -
Transmission system is an assembly of $ea
shafts that &aries the torque and seed com
from the en$ine as er requirement ' tran
it to the dri&e a5le throu$h clutch.
Tyes of ears used 6
ur ear,elical $ear7lanetary ear
,e
7lanetary $ear 6 used in automatic transmission
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Transmission system -
Tye of transmissions 6
1) Manual Transmission
2) #utomatic transmission
Manual transmission arran$ement 6
?) lidin$ mesh $ears bo5
@) Constant mesh $ears bo5
A) ynchromesh $ear bo5
Tyes of transmission on basis of seed
F) ? seed $ear bo5
2) @ seed $ear bo5
?) A seed $ear bo5
Transfer $ear bo5 6
It is a secondary $ear bo5
attached to the main $ear bo5 . It
ta"es the ower from the main$ear bo5 and deli&ers it to the
rear wheel or to all the four
wheels accordin$ to the dri&in$
requirement and the selection.
7roeller shaft 6
It is used to transmit the ower
from $ear bo5 to the differential(9ear wheel)
Transfe
rbo5
# i T i i
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#utomatic Transmission system -
There are three basic systems in
#3Transmission
Torque con&erter
- It is a "ind of de&ice used totransmit the ower from /n$ine
to the ear bo5
,ydraulic system
- ,ydraulic ressure is used to
shift the $ear system
ear system- ears are shifted by
hydraulic ressure in resonse
to the car seed and throttle
oenin$.
>ifferential
- To differentiate the Torque e&enly in both
left ' ri$ht wheels
- To comensate the difference in distance
that the dri&e wheel tra&el when the carrounds a turn
Tyes of $ears used in differential 6
1) ur be&el ears
2) iral be&el ears
ur be&el
Be&el $ear
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9' SUSPE(SIO( < STEE!I(#
usension ystem
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SUSPE(SIO(
yystem to absorb the road shoc"s to ro&ide a
comfort feel to the assen$ers.
Tyes of susension system 6
1. 9i$id susension - In ri$id susension %
both the wheels are connected throu$h a
ri$id beam. The shoc"s due to irre$ularities
are obser&ed by one wheel is artially
Transferred to the second wheel.
T
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)' M,Pherson Strut
This system uses a combination of
coil srin$ and shoc" absorber !oined
to$ether in the shae of tower as
shown in the fi$ure.
The wheel is held at the bottom by a
control arm% thus in this system there
is no uer control arm.
This system is an indeendent
susension system.
Mc7herson
trut
Strut
It is a suort ha&in$ one e
lower control arm and the
other to body $round.
/5tra 7urose 6 To a&oid t
mo&ement of the control arwhile mo&in$ on bums or
-' Torsion Bar t:pe
In this system % two lon$
rin$% ne end attache
other to the control arm.
obtained due to the twis
Torsion Bar
&' Control Arm t:pe
Control arm is connected to the &ehicle body at one end and holds the wheel at the
ther end. enerally two arms are used to hold the wheel% uer and lower control arms. The
srin$ and the shoc" absorber are laced between either uer or lower control arm.
Suspension S:stem Components
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SUSPE(SIO(
Suspension S:stem Components
1) rin$ 6unction of srin$ is to absorb the shoc"s
due to road irre$ularities.
Commonly used srin$s 6
- eaf rin$
- Coil rin$
2) hoc" absorber6 It absorbs3dam the &ibration of
srin$. Commonly used hoc" absorbers 6
- ,ydraulic hoc" absorber- as filled shoc" absorber
?) Torsion bar6 unction of torsion bar is same as that
of srin$. They are ri$id at one end
and they twist around the center as the susension
arm deflects.
Upper '!unt
Pist!n
F$uid
L!3er '!unt
Steerin% S:stemh f i i h h di i f h
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STEE!I(#
The urose of steerin$ system is to chan$e the direction of the
&ehicle mo&ement as desired by the dri&er
teerin$ can be 6
)6 Manuall: operated6 In this system % >ri&ers muscular
ener$y is directly used in steerin$ the wheels of the &ehicle
2) Power assisted6 In this >ri&er is aided by an e5ternal ower
assistance so as to lower down the steerin$ effort.
Mode of oeration 6
0:drauli, - 7ressure $enerated by a ower steerin$ um.
Ele,tri, a*a Ele,tri, Power Steerin% ;EPS6
- #n electric motor dri&en by the &ehicle electrical system andcontrolled by /C. #lso "nown as
Comonents of steerin$ system 6
1) teerin$ $ear bo5 - teerin$ $
rotary motion of the steerin$ w
motion of the tie rod which is
left and ri$ht wheels.
Tyes of teerin$ bo5es 6
2) 8orm and 8orm $ear
?) 9e-circulatin$ ball ' 0ut tye
@) 9ac" and 7inion tye
(teerin$ can be either be manual o
0:drauli, Power
Steerin%
Ele,tri, Pow
Steerin%
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=' FO! SAFET3
BRAKES
C f , d li i d b "
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SAFET3
The 7urose of bra"e is to slow down or sto the
&ehicle when e&er required.
Bra"es can be of three tyes 6
1) >rum Bra"es 68here a set of bra"e liners e5anda$ainst a bra"e drum leadin$ to bra"in$ of he &ehicle.
This is oerated manually or hydraulically.
2) >isc Bra"es 68here a set of Bra"e liners e5and
a$ainst a Bra"e disc leadin$ to bra"in$ of the &ehicle.
*acuum assisted ,ydraulically oerated Bra"es 6In this tye of bra"es % >rum3>isc bra"es are actuated
by the force of hydraulic ressure.
Reservoir
Master cylin
DDisc Brake
5 wayunion
Secondarypiston
Master CylinderIt Con&erts >ri&er foot effort in to hydraulic ressure awheel cylinders.
Bra"e Booster 6Ba"e booster is fitted in between the MCylinder and bra"e edal. It sulies the additional forcylinder as the dri&er resses the edal.
*acuum um6 It $enerates &acuum for the Bra"e boo
Comonents of ,ydraulic assisted bra"es 6
Anti 2o,* Bra*e S:stem ;ABS6
http://var/www/apps/conversion/tmp/scratch_2/Drum%20Brakes%20ppt.ppthttp://var/www/apps/conversion/tmp/scratch_2/Disc%20Brakesppt.ppthttp://var/www/apps/conversion/tmp/scratch_2/Disc%20Brakesppt.ppthttp://var/www/apps/conversion/tmp/scratch_2/Drum%20Brakes%20ppt.ppt -
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SAFET3
The function of the #B unit is to re&ent wheelloc" u (s"iddin$ of wheel) under bra"in$.
8heel loc" u (stoin$ of wheel) is not desired
for the followin$ reasons=-
1) 8ith the wheel loc" u the wei$ht of the mo&in$ carslides the car further% thus increasin$ the bra"in$distance.
2) #s the wheel is stoed% steerin$ the car is no lon$erossible and dri&er can loose the direction control.Tyres wear out faster.
* ensors are mounted on all four wheIt senses when loc" u is about to haenand the #B unit re$ulates (decreases)
ressure to that wheel accordin$ly. Thus under bra"in$% #B re&ents wheel
' maintains steerin$ control% on all surfac
8ithout #B
8ith #B
C!UMP2E >O(ES + $EFO!MATIO( SAFET3
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SAFET3
Crumle ones are deformablestructures% ro&ided in the car.
#d&anta$e= These areintentionally desi$ned to deform
durin$ an accident and absorbthe imact of the collision.
The side imact bars are ro&ided inside the doors toreduce in!uries durin$ collisions into the side of the car.
SI$E IMPACT BA!S +$EFO!MATIO( SAFET
Supplementar: !estraint S:stem ;S!S6 ;Air Ba%s6
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SAFET3
#irba$s are for rotectin$ head andchest re$ion of assen$ers
7resent in the teerin$ wheel for the
dri&er% dashboard area for the Co >ri&erand in doors3roof for rear assen$ers.
In an accident% the air ba$ system i$nites certain elements% which
burn raidly to create a lar$e &olume of $as (#mmonium 0itrate) to inflate the ba$.
The ba$ then bursts at u to 2 mh% faster than the blin" of an eyeJ Thus
cushionin$ the occuants. # second or so later% the $as dissiates.
# 8ord f Caution= Children $enerally below the a$e of 12 should not tra&el in the
front when cars are equied with the airba$.
Additional Sa"et: Features
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7re-tensioner (in seat belts)=
They are de&ices which incase of a se&ere imact% ti$hten theseat belt and re&ent the sli$ht forward motion that normal/9 seat belts ha&e.
They do so by either ullin$ the belt downwards near the reel
or ullin$ the belt buc"le. They are mostly used incon!unction with airba$s and load limiters and hold a ersonin for !ust a short while% enou$h for the airba$ to fully inflate.
i"e airba$s if once used% new ones ha&e to be installed.
SAFET3
oad imiter=
The load limiters are used to minimthat may be caused by the re-tensiose&ere imact% the re-tensioner ulwhile the airba$ fully inflates and th
releases some of the belt from the reoccuant is cushioned by the inflate
,ead 9estraints
,ead restraints installed on to of the seanec" in!uries (whilash in!uries) in the ca
Proper Restra!t
"t#o$t Proper
Restra!t
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?' EMISSIO(S CO(T!O2
1./5haust $as recirculation
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EMISSIO(S
6 # art of /5haust $ases are reused for combustion so as to
brin$ down the 05 le&el in emission (lowerin$ down the
/n$ine temerature).
2. 7ositi&e Cran"case &entilation
- #ir3fuel &aors are se$re$ated from Blow by $as
(constitutin$ /n$ine oil &aors ' air3fuel &aors) and sent bac"
to the inta"e manifold.
?. /&aorati&e emission control ystem
6 In this system % fuel &aors from the fuel tan" are send to
Inta"e manifold.
@. Catalytic con&erterIt consists mainly of three elements 6
1) ,oneycomb
2) 9eduction catalyst
?) 5idation Catalyst
2. 9eduction catalyst
6 It uses 7latinum and rhodium to hel in reducin8hen an 0 or 02 molecule contacts the catalyst% the
nitro$en atom out of the molecule and holds on to it% free
form of 2. The nitro$en atoms bond with other nitro$en
stuc" to the catalyst% formin$ 02. or e5amle=
&(O @ (& O& or&(O& @ (& &O&
?. 5idation Catalyst
The o/idation ,atal:stis the second sta$e of the catalytic con&erter. It reduces
the unburned hydrocarbons and carbon mono5ide by burnin$ (o5idi4in$) them
o&er a latinum and alladium catalyst. This catalyst aids the reaction of the C an
hydrocarbons with the remainin$ o5y$en in the e5haust $as.
or e5amle=
&CO O& @ &CO&
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' E2ECT!ICA2 < 0VAC
Char%in% S:stem9e$ulator 6 The function of re$ulator is to co
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The function of char$in$ system in #utomobile is to
$enerate% re$ulate and suly the electrical ener$y
for char$in$ the battery.
-
To suly the current demands of all the loads.- To suly constant &olta$e at all the conditions.
#lternator 6It con&erts the mechanical ener$y comin$
from the en$ine in to the /lectrical ener$y.
Current roduced by #lternator is
A'C + Alternatin% ,urrent
>ue to the mo&ement of rotor inside the stator% ma$netic
field de&elos and as a result #lternatin$ current is
roduced.
9e$ulator The function of re$ulator is to co
&olta$e comin$ from the alternator.
9ectifier6 The function of rectifier is to chan
in to >C current.
tartin$ circuit 6 To start the en$ine battery &
to the starter motor as the
dri&er switches on the i$nition.
E2ECT!ICA2
,*#C allows the assen$ers to control the climate
conditions inside the &ehicle to their comfort and
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0VAC
conditions inside the &ehicle to their comfort and
con&enience. The Basic functions of ,*#C=
Coolin% 0eatin% Ventilation
1) Comressor6 Comressor suc"s the refri$erant from thee&aorator and deli&ers at hi$h ressure to the condenser.
2) Condenser6 Condenser is !ust li"e radiator in which ,otrefri$ent is cooled.
?) 9ecei&er3>rier bottle6 9ecei&es the comressed and cooledrefri$erant and remo&es the moisture from that and also actsas a reser&ior.
@) /5ansion *al&e6 9ecei&es cooled and comressedrefri$erant% e5ands it and asses it to the e&aorator.
E/panded re"ri%erant %ases are ver: ,old'
A) /&aorator 6it is similar to radiator. The e5anded coldrefri$erant is assed o&er warm air from inside the &ehicle.
F) Blower6 Blower fan suc"s warm air from inside the&ehicle and asses it o&er the e&aorator so as to cool theinterior.
T0A(1 3OUD
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T0A(1 3OUDAUTOMOTIVE BASICS P!ESE(TATIO( B3
Automotive Ent
CarEager o
fa c e b o o k C a rE a ge r! o r "#. c om
$w i e r.c C a rE a ge r! o r "#o m
in %$a gra m . C a rE a ge r! o r"#co m
A & "' %.go o g"e . (C arE a ge r! o r"#co m