Maeda MK0003, Service Manual, Page: 95 / 348

2-67
7.4.4 PARKING BRAKE
The parking brake mechanically immobilizes the hydraulic motor output shaft while the traveling motor is standing
still.
[1] Effectiveness of parking brake
When neither port A or B is supplied with hydraulic oil, brake piston (1) is pushed toward the direction of arrow shown
in Fig. 6 by the force of spring (2).
In this process, the disk plate (4) fixed to cylinder barrel (3) by means of a half-moon shaped groove is in the pinched
position between the steel plates (6) and (7) that are likewise fixed to body 2 (5).
Resultantly, the rotation of cylinder barrel (3) is stopped by the friction force between disk plate (4) and steel plates (6)
and (7). (Refer to Fig. 6.)
[2] Release of parking brake
When either port A or B is supplied with hydraulic oil, it will be guided through chamber (8) in Fig. 7.
The hydraulic oil will overcome the spring (2) tension and moves the brake piston (1) to the arrow direction in Fig. 7.
Resultantly, disk plate (4) and steel plates (6) and (7) will be released and the friction force dissipates, making the
cylinder barrel (3) rotatable. (Refer to Fig. 7.)
Pressure