Kubota D1803-CR-E4, Руководство по ремонту

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(1) Cylinder port
(2) Solenoid
(3) Armature
(4) Discharge port
(5) Piston
(6) Cylinder
(7) Suction port
a
High suction volume
b Low suction volume
c ON
d OFF
e Large
f Small
(A) To pressurizing section
(B) From fuel pump
[A] SCV
[B] No delivery (current ON)
[C] When the solenoid is electri-
fied
[D] Maximum delivery volume
(current OFF)
The SCV has a function of delivering to the
pressurizing part
The SCV is a proportional control valve that adjusts the
amount of fuel delivered from the fuel pump to achieve
the fuel pressure requested by the engine.
The SCV is a linear solenoid type electromagnetic
valve and the engine ECU controls the time the
solenoid is electrified (duty ratio control).
When current flows through the solenoid, the armature
moves based on the duty ratio and pushes on the
cylinder and fuel flow changes based on position of the
cylinder enabling suitable fuel flow.
Pump Body (Pressurizing Part )
(8) IO valve
(9) Outlet valve
(10) Inlet valve
(11) Plunger chamber
(12) Plunger
(13) Plunger barrel
(14) Spring (15) Tappet
(16) Fuel camshaft
(C) From SCV
(D) To rail
[E] Suction stroke
[F] Compression stroke
The pump body (pressurizing part) applies pressure to
the fuel supplied from the suction control valve, has a
function of supplying fuel to the rail.
The engine side fuel camshaft (9) rotates and during
the lowering stroke, the spring cause the plunger to
lower.
An optimal amount of fuel adjusted by the suction
control valve is suctioned through the IO valve and into
the plunger chamber (11).
Rotation continues and during the lift stroke of the cam
the plunger rises, pressurizes the fuel, and supplies it
through the IO valve to the rail.
4. ENGINE
MECHANISM
3. Fuel system
4-22
D1803-CR-E4,D1803-CR-TE4,D1803-CR-TIE4,V2403-CR-E4,V2403-CR-TE4,V2403-CR-TE4BG,V2403-CR-TIE4
KiSC issued 12, 2018 A