Kubota D1102-B, Руководство по ремонту, Страница: 22 / 109

KiSC issued 09, 2007 A
(A) Pressurization of Fuel
(b)
(a)
(c)
(d)
(f )
(e)
Fig.
1
Fig. 2
How it works:
1 ) When the pl u nger is at the bottom of its stroke, f uel from
the f uel cha mber enters the del ivery chamber through the
f eed hole ( F ig.
1)
2)
As the ca mshaf t rotates, pl u nger moves u pward, the
stroke of f uel pressu ri zation begi ns. ( Fig.
2)
3)
As the pl u nger moves u p, the pressu re i ncreases u nti l it
opens the del ivery va l ue a nd sends the pressu ri zed f uel to
i nject ion nozzle th rough the i njection pi pe. ( Fig.
3)
4)
Send i ng of f uel stops as soon as the control groove meets
the f eed hol e. Fuel f l ows out th rough the pl u nger's center
hol e, control groove and feed hole, then backs to the f uel
cha m ber. As
a
resu lt, the pressu re fa l ls a nd the stroke is
com pleted. ( F i g.
4)
0011F044
Fig.
3
Fig.
4
(A) Pressurization of fuel
(a) Delivery Chamber
(b) Delivery Valve
(c)
Feed Hole
(d) Fuel Chamber
(e) Plunger
(f ) Control Groove
(A)
Injection Control
Fig.
1
Fig.
2
t
(e)
Quantity control of fuel injection
1) No fuel
The f eed hole meets the control-groove before bei ng cl osed
by the pl u nger top. Th erefore, no f uel is pressu ri zed a nd
i njected. ( Fig.
1)
2)
Partial fuel
Pl u nger rotates a certa i n a mou nt when the control rack is
moved i n the direction of the a r row. Ef f ective stroke
A
mea ns the d ista nce wh ich the f eed hole is closed by the pl u n-
ger before meeti ng the control groove on th e pl u nger. There-
fore, f uel is i njected as mu ch as the amou nt of effective
stroke. (Fig.
2)
3)
Maxim u m fuel
As the control rack moves the greatest possi ble a mou nt i n
the d i rection of the a rrow, the eff ective stroke A is max i-
mu m a nd the ma x i m u m a mou nt of f uel is i njected.( Fig. 3)
I