PRONAR T672ECO, User Manual

Page: 60 / 150

Chapter 3
3.9
PRONAR T672ECO
Construction and principle of operation
3.4 SERVICE BRAKE
Depending on the version, the trailer is
equipped with one of three types of service
brake:
• overrun brake,
• 2-wire conduit pneumatic system -
fi gure (3.7).
• 2-wire pneumatic system with ALB -
fi gure (3.8).
The service brake is activated from the
driver's cab by pressing the tractor brake
pedal. The task of the control valve used
(1) - fi gure (3.6) in pneumatic systems is to
activate the trailer's brakes simultaneously
with the tractor's brake on. In addition, in
the event of an unforeseen disconnection
of the hose between the trailer and the
tractor, the control valve automatically ap-
plies the machine's brake.
The trailer is braked (automatically braked)
by pressing the button (3) fully. The valve
used has 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 op-
eration of the brakes.
The three-band braking force regulator (2)
used in pneumatic systems adjusts the
braking force depending on the setting.
C
B
A
259-G.19-1
1
4
2
3
Figure 3.5 Control valve and braking force
regulator
(1) control valve (2) brake force regulator (3)
brake release button (4) setting lever
(A) 'UNLOADED’ position
(B) ‘HALF LOAD’ position
(C) ‘FULL LOAD’ position
621-G.04-1
2
1
Figure 3.6 Pneumatic connections
(1) connection body
(2) connection body