Kubota M108S, Руководство по ремонту

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1-M21
M108S, WSM ENGINE
(2) Engine ECU (Electronic Control Unit)
The engine ECU constantly ascertains the status of
the engine through signals from the sensors, calculates
fuel injection quantities etc. appropriate to the conditions,
actuates the actuators, and controls to keep the engine
in an optimal state.
The injectors are actuated by the charge circuit in the
engine ECU. The charge circuit is provided to enable
high-speed actuation of the injectors. The charge circuit
has a high-voltage generation device (DC/DC converter)
and supplies high voltage to the injectors to actuate the
injectors at high speed.
The engine ECU also has a diagnosis function for
recording system troubles.
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Fuel Injection Control
This system effects more appropriate control of the
fuel injection quantity and injection timing than the
mechanical governor or timer used in the conventional
injection pump. The engine ECU performs the
necessary calculations based on the signals that are
received from the sensors located on the engine and the
tractor.
Then, the engine ECU controls the timing and
duration of the current that is applied to the injectors in
order to obtain optimal injection timing and injection
quantity.
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Various Types of Fuel Injection Control Functions
1) Fuel Injection Quantity Control
This control replaces the function of the governor in
the conventional injection pump. It achieves optimal
injection quantity by effecting control in accordance with
the engine speed and accelerator opening signals.
2) Fuel Injection Timing Control
This control replaces the function of the timer in the
conventional injection pump. It achieves optimal
injection timing by effecting control in accordance with
the engine speed and the injection quantity.
3) Fuel Injection Rate Control (Pilot Injection
Control)
This function controls the ratio of the fuel quantity that
is injected from the orifice of the injector within a given
unit of time.
4) Fuel Injection Pressure Control
This control uses the rail pressure sensor to measure
the fuel pressure, and it feeds this data to the engine
ECU in order to control the pump discharge quantity.
W1018659
(1) Engine ECU (Electronic
Control Unit)
(2) ECU Connector
KiSC issued 06, 2007 A