BUCKET GP-ADJ& 1579350 - Caterpillar

Illustration 1 g01487093
Parking brake (partial view) (1) Cover (2) Orifice (3) Piston (4) Shaft (5) Barrel (6) Passage (7) Spring (9) Spindle (10) Piston chamber (11) Separator plate (12) Friction plateThe parking brake for the travel motor is activated by spring pressure and the parking brake is released by hydraulic pressure. When pump oil is supplied to the travel motor, the parking brake releases. The motor starts rotating. When no pump oil is supplied to the motor, the motor stops and the parking brake engages.In the parking brake section of the travel motor, separator plates (11) are splined to spindle (9). Friction plates (12) are splined to barrel (5) .When no pump oil is supplied to the travel motor, piston (3) is forced to the right by the force of spring (7). The oil in piston chamber (10) now flows through orifice (2) to the motor case drain line. When piston (3) moves to the right, separator plates (11) and friction plates (12) are forced together against spindle (9) by spring (7). The rotation of the barrel (5) and shaft (4) stop. The parking brake engages.Orifice (2) in piston (6) restricts return oil flow from piston chamber (10). The restriction of the 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.