Operation Manual
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multi-way valve to push the cylinder piston move up, so as to realize lifting. Meanwhile, the oil in the
small chamber of the lifting cylinder returns to the oil tank through the multi-way valve.
When the control lever is at neutral position, the boom valve stem is kept at the neutral position under
the action of the return spring. Ensure that the large and small chambers of the lifting cylinder are in
locking states and the boom stops working.
After pushing the control lever forward to “Lower” position, continue to move it tothe “Float” position. In
this case, the multi-way valve switches on oil pump, oil tank, large and small chambers of the lifting
cylinder, and the lifting cylinder piston is in floating state in the cylinder so that the bucket cutting edge
can float up and down with topographic relief.
The operations of boom “Lower” and bucket “Tilt Down” are as follows when the engine is shutdown:
When the boom is at “Lift” position, in case of a sudden shutdown, lower the boom to the ground
slowly.
When pushing the control lever forward to “Lower” or “Float” position, the boom valve stem moves
forward to connect the oil port of the lifting cylinder large chamber with oil tank. Under the action of the
working device’s deadweight, the bucket drops to the ground.
To achieve the bucket “Tilt Down”, move the tilt valve stem forward so that the oil in the large chamber
of the tilt cylinder can return into the oil tank. At this time, open the filling valve of the first part of
multi-way valveto ensure that the oil port of the tilt cylinder small chamber is also connected with oil
tank. Under the action of the working device’s deadweight, the “Tilt Down” is achieved.
(ii) Structures & performances of main components
1.
Oil return filter: used for filtering the returned oil of the system.
2.
Gear pump: shares model CBG2050 with hydraulic steering system. Output: 50ml/r.
3.
Oil suction filter: used for filtering the oil sucked by oil pump.
4.
Oil tank: shared between working device hydraulic system and hydraulic steering system with a
capacity of 80L.
5.
Lifting cylinder
Piston rod
Shaft
sleeve
Dust ring
Spring
retainer ring
Support
ring
O-ring
Guide
sleeve
Hole square
ring
Cylinder
block
