PRONAR T285/1, Руководство оператора

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SECTION 3 Pronar T285/1
3.13
The hook trailer is equipped with the central hydraulic system with the system of electro-
hydraulic protections. The hydraulic system is supplied with oil from the tractor external
hydraulic system and controlled by the tractor hydraulic manifold and it performs the following
functions:
•
hydraulic interlock of suspension,
•
hydraulic interlock of load box,
•
hydraulic tipping and hydraulic switching between "hook trailer" and "tipper"
functions,
•
hydraulic hook frame.
The hydraulic interlock of suspension blocks the rocker arms while unloading the load box.
During operation of the hydraulic system manifold lever, the suspension interlock levers (3) –
figure (3.8) are extended first and then, when a proper pressure is reached, raising cylinder
(4) can be extended. When extending the raising cylinder, the limit valve (5a) is activated to
prevent unlocking the suspension. The suspension will be unlocked when the raising cylinder
is completely withdrawn (the rest position of the tipping frame). Anti-shock valves (6) protect
the system against sudden pressure jumps and ensure smoother operation of cylinders.
Hydraulic interlock of load box ensures that the load box is secured to the trailer chassis
during transport as well as during material unloading. The interlock is operated from the
tractor cab using hydraulic system manifold lever. When the load box interlock cylinder (7) is
being extended, limit switch (8) is disconnected and hook frame cylinder (10) can not be
operated. When extending the raising cylinder (4), the limit valve (5b) is activated to prevent
unlocking the load box. Hook frame is operated only when the load box is unlocked.
The system is equipped with a hydraulic locks (11) located on the cylinders (7.10).
Application of hydraulic lock improves safety of trailer operation. In the event of damage to
hydraulic system conduits (rupture, loss of tightness), the hydraulic lock will lock the cylinder
in a fixed position.
Control of hydraulic tipping with hydraulic switching between "hook trailer" and "tipper"
functions and control of the hook frame are described in chapter 3.2.2 (TIPPING FRAME).