COMPONENT OPERATION / Travel Device PARKING BRAKE The parking brake is a negative-type brake released when pilot pressure oil is applied to piston chamber (2). The parking brake is automatically applied except during travel operation. Friction plate (5) is connected to rotor (7) and plate (4) is connected to casing (6) via spline couplings respec- tively. When spring (1) pushes piston (3) and friction plate (5) comes into contact with plate (4), the parking brake is applied. (Refer to the pilot circuit in the Hydraulic System group / SYSTEM as for pilot oil flow.) 1 2 3 4 5 6 7 T1J1-03-05-003 1 - Spring 3 - Piston 5 - Friction Plate 7- Rotor 2 - Piston Chamber 4 - Plate 6 - Casing T3-5-12