Bendix Commercial Vehicle Systems ATR-1 ANTILOCK TRACTION RELAY 02/11 User Manual

Page 4

FIGURE 6 - SERVICE BRAKES RELEASING

FIGURE 7 - TRACTION CONTROL SERVICE BRAKE APPLICATION

SERVICE BRAKES RELEASING (FIGURE 6)

When the brake application is released, air from above
the relay piston fl ows back through the blend back and
service pistons to the foot brake valve and is exhausted.
As air pressure is reduced above the relay piston, pressure
beneath it lifts the piston away from the exhaust valve and
opens the exhaust passage. Air from the service brake
chambers returns to the ATR-1

™

valve and fl ows out the

open exhaust.

TRACTION CONTROL SERVICE
BRAKE APPLICATION (FIGURE 7)

GENERAL

While under the control of an antilock traction controller,
the ATR-1

™

valve’s solenoid is able to initiate a brake

application that allows the traction system to control wheel
spin upon acceleration under 25 mph. When wheel spin
is detected and the vehicle is stopped, or moving at any

RELAY PISTON

TRACTION

SOLENOID

INLET EXHAUST

CHECK VALVE

CONTROLLER

REAR AXLE

RESERVOIR

SPRING BRAKE

MODULATOR

BRAKE

VALVE