Mitsubishi 4DQ50 Service Manual page 51

in touch with the full·load stopper, shifter will directly came in touch the tension·lever along
with the rise of r.p.m. Accordingly, the ungleich·spring will be pressed under a fixed
condition (Fig. 8, Fig. 9).
With the result of such movement as above, the guide·lever and the control· rack move in
the "STOP" direction up to the corresponding volume of ungleich and "ungleich" the jet
volume. When the machine reaches the full·load and the centrifugal force wins over the '
tension of the governor·spring, the tension·lever is pushed back. The shifter, the guide·lever
and the control·rack move in the direction of "STOP" and obtain a new balance at the place
where small jet volume suitable to the load condition of engine may be obtained.
4. Work of Ungleich
The fuel supplying curve is shown in Fig.
10.
In this figure the fuel, which will burn
smokelessly (smoke·limit) at the regular r.p.m. and at a fixed load is ploted by inspecting the
jet condition against engine cylinder per each stroke adopting the r.p.m. as parameter. The
of
"*~~-=---~-A=-~
1 ..........................
1..-.........
~
:!'
.;:
~
Nl
•• p.
m.
of
En9ne
N2
Fig. 10
fuel jetting volume curve in the same figure is shown at the full·load position of the
control·rack by adopting the fuel jet volume which is supplied by the injection pump per
each stroke as function. This fuel demanding curve shall be made similar to the fuel outlet
curve within the limit of possibility. In other words, the fuel necessary for engine shall be
injected smokelessly so as to operate engine without hindrance.
Fig.
10
shows the following facts: The demand for engine fuel decreases as the r.p.m.
rises (worse condition of air inhalation), on the other hand, the injection pump, when
~e
control rack placed on a fixed condition, injects more fuel as the r.p.m. rises. No engine can
burn (consume) this increased fuel without giving out smoke. If the maximum jet volume of
the injection pump is adjusted to themaximum r.p.m. of the engine so as to meet the
requirement at full·load condition the r.p.m. of the engine is lowered and sufficient output
cannot be obtained. In an ordinary case, therefore, the maximum jetting vplume of the
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