Clutch
Brief description of the struc鄄
ture
The clutch equipped for this series
truck is single -plate dry type di鄄
aphragm spring clutch, outside di鄄
ameter of the driven plate is 椎254.
The hydraulic control unit of the
clutch is composed of the clutch
pedal尧oil storage cup尧 release cylin鄄
der (master cylinder)尧 wheel cylinder
and oil pipe. It is shown in the below
figure.
The clutch pressure plate and cover
assembly is fixed to the pressure
cover with a diaphragm spring
through a set of rivet and press out
the pressure plate on the outside
edge. The diaphragm spring is both
pressure element and release ele鄄
ment. Because the diaphragm spring
has good nonlinear characteristic,
the pressure of the diaphragm spring
keep steady, transfer the engine
torque stably, and the releasing force
is small, if equipped with hydraulic
control unit the force should be less.
The two -stage torsion damper and
autocompensation absorbing shock
deoscillator have been fixed on the
driven plate assembly to decrease
the idling vibration and vibration at
ordinary speed commendably. The
spline of the inner hole on the driven
plate is involute type, the small inter鄄
tooth space尧 stable transmission and
1尧pedal 2尧piston 3尧push rod
4尧release cylinder 5尧oil storage cup
6尧oil pipe 7尧air bleed plug
8尧wheel cylinder
9尧release fork
10尧release bearing
schematic diagram of the
hydraulic control unit on the clutch
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HFC1020
series trucks
wavy spring mounted between two
friction linings effectively decrease
the impact force because of fast
linkage of the clutch. The release
bearing of the clutch is radial thrust
bearing with closed spherical sur鄄
face. It does not need to add oil.
And after wear the clearance can be
eliminated automatically.
Adjustment of the clutch operat鄄
ing system
1. Adjust the limit screw of the clutch
pedal (below figure) to make sure
that the free play of the pedal is 3耀
5mm.
2. Adjust the master cylinder of the
clutch: loosen the locknut on the
push rod of the master cylinder, ro鄄
tate the end of the push rod to con鄄
tact gently with the piston of the
master cylinder, then rotate the push
rod for 3/4 circle in the contrary di鄄
rection, tighten the locknut of the
push rod, now the clearance be鄄
tween the push rod and the piston is
about 0.5耀1mm.
3. Adjust wheel cylinder of the clutch
Take off the return spring of the re鄄
lease fork, push the wheel cylinder
piston to the bottom of the cylinder,
loosen the locknut on the push rod,
push the release fork towards the
backside of the engine to the posi鄄
tion where the release bearing and
the release fork contact barely, turn
the spherical nut until it contacts with
the release fork, then turn back the
spherical nut on the push rod for 3
circles, tighten the nut, install the re鄄
turn spring of the release fork.
4. Bleed air from wheel cylinder of
the clutch
Having air or oil leakage in the hy鄄
draulic pipeline of the clutch is unal鄄
lowed, or else, it can result in the
disability of the pedal尧 deficiency of
clutch pedal
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