LINK AS-TRACK 2364105 - Caterpillar

Illustration 1 g01232768
Parking brake (parking brake engaged)
(1) Brake pilot valve
(2) Port
(3) Drive shaft
(4) Head
(5) Passage
(6) Brake spring
(7) Housing
(8) Barrel
(9) Friction plate
(10) Separator plate
(12) Piston chamber
(13) Brake piston
(14) Passage
(15) Spring
(16) Valve
(17) Retainer
(18) Orifice In the parking brake section of the travel motor, separator plates (10) are splined to housing (7). Friction plates (9) are splined to barrel (8).When the travel lever/pedal is returned to the NEUTRAL position, the oil delivery from the pump is blocked at the travel control valve in the main control valve. Valve (16) moves to the right by the force of spring (15). The oil delivery from the pump does not flow through valve (16). The force of the oil pressure on the left side of brake piston (13) now becomes lower than the force of brake spring (6). The brake piston is pushed slowly to the left by the force of the brake spring. The oil in piston chamber (12) now flows through passage (14) and passage (5). The oil flows through orifice (18) and into the valve of the motor case drain line. Friction plates (9) and separator plates (10) are forced together by the force of brake spring (6). Friction plates (9) are splined to barrel (8). Separator plates (10) are splined to housing (7). When the separator plates and the friction plates are forced together, the rotation of drive shaft (3) in the travel motor gradually slows to a stop as the parking brake engages.Orifice (18) restricts return oil flow from piston chamber (12). The restriction of the return oil flow delays the application of the parking brake. The parking brake is delayed in order to give the machine time to stop. Earlier wear and/or damage to the machine could result if the machine stayed in motion.
Illustration 2 g01232769
Parking brake (brake released)
(1) Brake pilot valve
(2) Port
(3) Drive shaft
(4) Head
(5) Passage
(6) Brake spring
(7) Housing
(8) Barrel
(9) Friction plate
(10) Separator plate
(12) Piston chamber
(13) Brake piston
(14) Passage
(15) Spring
(16) Valve
(17) Retainer
(18) Orifice When a travel lever/pedal is moved from the NEUTRAL position, the oil delivery from the pump flows to the inlet port of the travel motor from the travel control valve in the main control valve. A portion of the oil delivery from the pump flows through port (2). Valve (16) moves to the left against the force of spring (15). The oil then flows through passages (5) and (14) to piston chamber (12). Brake piston (13) moves to the right against the force of brake spring (6). The spring force that is holding friction plates (9) and separator plates (10) together is released. Barrel (8) and drive shaft (3) start to rotate.