PRONAR T669/1, Operator'S Manual, Page: 51 / 137

SECTION 3 Pronar T669/1
3.7
In the rear part of the load box there is the tailgate (5) which is opened and closed using
hydraulic cylinders.
In order to enable more precise unloading of loose materials there is a slide gate opening (2)
– figure (3.3), placed in the tailgate. A chute (3) for the trailer, secured under the lower edge
of the slide opening may be supplied as additional equipment.
As an option, 1,000 mm silo wall extensions or 580 mm wall extensions with the net
protection can be installed on the trailer.
3.2.3 MAIN BRAKE
The trailer is equipped with one of four types of main brake:
•
single line pneumatic system with three position regulator, figure (3.4),
•
double line pneumatic system with three position regulator, figure (3.5),
•
double line pneumatic system with automatic regulator, figure (3.6),
•
hydraulic brake system, figure (3.7).
The pneumatic or hydraulic brakes are activated from the tractor driver's cab by pressing on
the brake pedal. The function of the control valve (2) - figures (3.4), (3.5) and (3.6), is the
operation of the trailer's brakes simultaneously when tractor's brakes are applied.
Furthermore, in case of an inadvertent disconnection of the line between the trailer and the
tractor, the control valve will automatically activate trailer's brakes. Valve used in the system
is equipped with a circuit causing the brakes to be applied when trailer is disconnected from
the tractor, (compare with figure (3.8). When compressed air line is connected to the tractor,
the device automatically applying the brakes now changes its position to allow normal brake
operation.