Valmet 309 - Page 94

T
JECTOR
BOSCH
The
lnJector has a four-hole nozzle. The maln
parfs
ot thg I njec'tor
ar6 the nozzle
holder
and
ih€ nozzla
tlp.
The funcilon
of
ihe
I
nJecfor
ls lo taed
tuel lnio ihe
cvllnder ln the form
of
a flne
vopour and
fo starl cnd
cui
off ths
lnJec+lon
rapldly.
The
lnJector ls controlled
by th6
fuel
pi€ssuro.
912
l. Fu€l
Inlet 2. Overtlor
plpe
connectlon
l.
Shlm 4.
Pressure sprlng 5. Pressure
pln
6.
Nozzle
body 7. Nozzle needle 8. Pressure
chamb€r 9. Nozz le hole
The
fuel
pressure
ls dlrecled to
ihe
conlc
pressur€
should€r o{ the .pzzle need le
(7).
Hhen
thls
pressure
ls
greater
fhan the
reslst-
Ing forcg
of ihe
pressure
sprlng
(4)
li
ralses
the
n€dle froi!
Its seat. Fuel ls then e
iected
through
the
holes
(9)
In
the
nozzle bod-'I
(6)
Into ihe
combus+lon chamber
ol +he cvllnder.
The
tenslon
ot
ihe
pressure
sprlng,
lrhlch
delerm
I nEs
the open I ng
pressure
o{
fhe
InJecfor,
cän
be
adJusied wlth shlms
(l).
The ovgrflow
fuel lubrlcatlng fhe nozzle needle
ls led
to
lhe
overfloy
plpe
ond back +o
fhe
fuel
iank.
INJECIoR C
Y
(61I
englnes)
The
InJecior manutactured by CAV ls
prlnclpally
the same as fhe Bosch
InJector,
rlth regard
io
qanstructlon
and tuncilon. The
greaiest
dlfferences
ln
construcilon
are to do wlfh
the
lnJecior
fixlng and
the
adjustn|en+ of the
openlng
pressure.
The InJeclor
dpun+lng lugs
are
casl ln the body
ond
the openlng
pressure
ls
adjus+ed wlth an ödJustlng
nui, rl+houf
ssparate
sh
lms.
l. Fuel
Inle+
2. Ov€rt
low
plDe
connec+lon
f. Adjusting
nui 4.
Pressure
sprlng
5. Pressure
Dln
6.
Nozzle bodv 7.
Nozzlg
ne€d le 8.
Nozzle
hole
2
I
-8