Pneumatic Brakes System - PRONAR T400 Operator's Manual

Pronar T400
Hydraulic oil from quick couplers (3) goes through hoses (2) to the cylinder (1) which,
depending on the direction of oil supply, opens or closes the trailer's front extension.

3.8 PNEUMATIC BRAKES SYSTEM

The T400 trailer is equipped with one of two types of service brake systems (pneumatic
brakes):
• Two-line pneumatic system with manual braking force regulator - figure (3.8) -
standard equipment,
• Two-line pneumatic system with automatic braking force regulator - figure (3.9) -
optional equipment.
The service brake is activated from the tractor driver's workplace by pressing the tractor
brake pedal. The control valve activates the trailer's brakes simultaneously when the tractor's
brake is applied. In addition, in the event of an unforeseen disconnection of the conduit
between the trailer and the tractor, the control valve (2) automatically actuates the trailer
brake. The valves used have a brake release system, used when the trailer is disconnected
from the tractor.
After connecting the air line to the tractor, the release device automatically adjusts to the
position enabling normal brake operation.
The brake cylinders (6) used in the installations are mounted on specially prepared brackets
welded to the driving axles. They are membrane actuators. The air supplied to the cylinder
exerts pressure on the diaphragm, which in turn moves the cylinder piston rod and rotates
the axle expander lever. The return of the actuator to the neutral position is supported by the
extraction springs.
3.12
CHAPTER 3