Bendix Commercial Vehicle Systems ATR-1 ANTILOCK TRACTION RELAY 02/11 - Manual (Page 4)

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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
BRAKE
VALVE
RELAY PISTON
TRACTION
SOLENOID
MODULATOR
INLET EXHAUST
CONTROLLER
REAR AXLE
RESERVOIR
SPRING BRAKE
EXHAUST
CHECK VALVE