| 摘要 |
PROBLEM TO BE SOLVED: To reduce the number of components to operate hydraulic control portions by controlling a plurality of hydraulic control portions by a prescribed proportional valve.SOLUTION: A hydraulic system includes hydraulic pumps 66a, 66b discharging a hydraulic fluid, a hydraulic apparatus 57 operated by the hydraulic fluid, a plurality of hydraulic control portions 63, 59 controlling the hydraulic apparatus by changing an operation state according to a pressure of the hydraulic fluid, and a proportional valve 45 connected to the plurality of hydraulic control portions and capable of setting a pressure of the hydraulic fluid supplied to the hydraulic control portions. The hydraulic apparatus includes a traveling motor 57, the plurality of hydraulic control portions include first hydraulic switch valves 63 of which an operating state is changed by a pressure of the hydraulic fluid to change a speed of the traveling motor, and brake mechanisms 59 of which an operating state is changed by the pressure of the hydraulic fluid to brake the travelling motor and to release the braking.SELECTED DRAWING: Figure 1 |
