BEARING-TAPERED ROLLER 3625414 - Caterpillar

Service Brake and Parking Brake Operation
Service Brakes Released
Illustration 3 g01226142
Brake Control Valve (11A) Proportional Brake Solenoid (Left Brake) (11B) Proportional Brake Solenoid (Right Brake) (13) Parking Brake Solenoid (14) Secondary Brake Solenoid (15) Secondary Brake Valve (16) Parking Brake Valve (20A) Reducing Spool (Left Brake) (20B) Reducing Spool (Right Brake) (23A) Passage to Left Brake (23B) Passage to Right Brake (24) Pump Supply Oil (BB) Cutaway Section (CC) Component Surface (FF) Activated Components (GG) Tank Pressure (JJ) High Pressure (KK) First Pressure Reduction (PP) Pilot PressureWhen the operator releases the service brake pedals, the position sensor sends a signal to the power train ECM. The power train ECM increases the current to the proportional brake solenoids (11A and 11B). The amount of current that is sent to the solenoid is directly proportional to the position of the service brake pedal.The increased current increases pilot pressure to reducing spool (20A and 20B). The reducing spools move downward in order to allow pump oil to flow to the brakes through passage (23A and 23B). The pressure releases the brakes.Left Turn Using The Service Brake
Illustration 4 g01226467
Brake Control Valve (11A) Proportional Brake Solenoid (Left Brake) (11B) Proportional Brake Solenoid (Right Brake) (13) Parking Brake Solenoid (14) Secondary Brake Solenoid (15) Secondary Brake Valve (16) Parking Brake Valve (20A) Reducing Spool (Left Brake) (20B) Reducing Spool (Right Brake) (23A) Passage to Left Brake (23B) Passage to Right Brake (24) Pump Supply Oil (BB) Cutaway Section (CC) Component Surface (FF) Activated Components (GG) Tank Pressure (JJ) High Pressure (KK) First Pressure ReductionNote: Illustration 4 shows the service