END 8A9210 - Caterpillar

Illustration 1 g01032846
(2) Solenoid valve for the swing parking brake (8) Pilot oil manifoldThe solenoid valve for the swing parking brake (2) is located on pilot oil manifold (8). When any one of the joysticks is moved from the NEUTRAL position, the solenoid for the swing parking brake is energized in order to release the swing parking brake. When the solenoid valve for the swing parking brake is energized, pilot oil flows to the swing motor in order to release the swing parking brake.Note: Operation of the travel levers/pedals will not release the swing parking brake.
Illustration 2 g00687102
Swing parking brake (disengaged position) (2) Solenoid valve for the swing parking brake (3) Spool (4) Spring (5) Passage (6) Passage (7) Port (pilot system oil) (8) Pilot oil manifold (9) Spool chamber (10) Line (11) Body (swing motor) (12) Friction plate (13) Separator plate (14) Piston chamber (15) Port (swing motor) (16) Cylinder barrel (17) Brake piston (18) Brake spring (19) Motor headThe swing parking brake is located between motor head (19) of swing motor and body (11). The swing parking brake consists of the following components : brake spring (18), brake piston (17), separator plate (13) and friction plate (12). Friction plate (12) is splined to cylinder barrel (16). Separator plate (13) is splined to body (11). Separator plate (13) and friction plate (12) move in an axial direction.When the joysticks are moved from the NEUTRAL position, the implement/swing pressure switch senses the increase in pilot oil pressure at the pilot control valves. The implement/swing pressure switch changes to the ON position. The implement/swing pressure switch sends an input signal to the engine and pump controller. The engine and pump controller energizes the solenoid valve for the swing parking brake (2) .When the solenoid valve for the swing parking brake (2) is energized, spool (3) moves in a downward direction against the force of spring (4). Pilot oil in passage (7) flows through spool chamber (6) and line (10) to port (15) of the swing motor. The pilot oil now enters piston chamber (14). The pilot pressure causes brake piston (17) to move upward against the force of brake spring (18). The force that holds separator plate (13) and friction plate (12) together is released. When the swing parking brake is released, the swing operation of the upper structure is enabled.Note: If the swing parking brake becomes inoperable due to failure of the solenoid valve for the swing parking brake (2), the swing brake can be released by turning the temporary brake release screw in a clockwise direction until the temporary brake release screw stops.
Illustration 3 g00686766
Swing parking brake (engaged position) (2) Solenoid valve for the swing parking brake (3) Spool (4) Spring (5) Passage (6) Passage (7) Port (pilot system oil) (8) Pilot oil manifold (9) Spool chamber (10) Line (11) Body (swing motor) (12) Friction plate (13) Separator plate (14) Piston chamber (15) Port (swing motor) (16) Cylinder barrel (17) Brake piston (18) Brake spring (19) Motor headWhen the joysticks