| 摘要 |
PURPOSE:To reduce the number of hydraulic pressure supply ports and also the size of th valve body by providing the first and second main speed changing ports separately in the first and second switch valves and by supplying hydraulic pressure via the hydraulic circuits provided in the respective spools. CONSTITUTION:The valve body 13 of the first switch valve 3 has a port 16 connected to a hydraulic pump 1, a port 17 connected to a directional clutch switch valve 5, a port 18 connected to the port 36 of the second switch valve 14, ports 19, 20, 21 connected to cylinders 8, 9, 10 for the first, second and third speed clutches, ports 22, 23, 24 connected to a low-speed clutch cylinder 11, and a drain port 25. The valve body 33 of the second switch valve 4 has ports 37, 38, 39 connected to the flow paths 54, 55, 56 and ports 19, 20, 21, and ports 40, 41, 42 connected to a high-speed clutch cylinder 12. |
