PRONAR T683P, User Manual

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CHAPTER 3 Pronar 683P
3.15
Hydraulic system of support - figure (3.10) is used for automatic unfolding and folding of the
support leg (3). This is done by extending or retracting the piston rod of the hydraulic cylinder
(4). The support system is fed through the conduit (1) with oil from the tractor's hydraulic
system. The tractor's external hydraulic oil distributor is used to control the support cylinder
operation.
The system is equipped with a hydraulic lock (5) located on the actuator (4). The use of a
hydraulic lock increases the safety of using the trailer. In the event of raising or lowering the
support, the system conduits may be damaged (abrasion, unsealing), in which case the
hydraulic lock will lock the cylinder (4) in a fixed, unchanged position.
ADVICE
The support's hydraulic system was filled with L-HL32 Lotos hydraulic oil.
3.2.6 PARKING BRAKE
The parking brake is used to immobilize and secure the trailer against rolling away when
parked. The trailer is equipped with a parking brake with a crank mechanism - figure (3.11).
The trailer is immobilized by turning the crank of the mechanism (1) clockwise as far as it will
go. When turning the lever, the steel cable (2) is tensioned, which, through the mechanism,
tightens the next cable guided through the rollers (3). The cables are connected with the
wheel axle expander levers (4). Tensioning of the cable tilts the expander levers, which
spread the brake shoes of the wheel axle, immobilizing the trailer.