| 摘要 |
PROBLEM TO BE SOLVED: To provide a simple pressure control device for a hydraulic circuit obtaining a brake pressure in no relation to a flow amount and pressure of a steering circuit. SOLUTION: A no-load valve 24 is switched to the no-load position side against a spring 31 energized to a flow amount priority position by a pressure generated in a second end part 27. A check valve 38 is provided between a first flow path 32 and a second flow path 37 connected to a second hydraulic circuit 12. In valve means 41, in accordance with a pressure in the second flow path, a pressure is controlled in the second end part of the no-load valve, in this way, a pressure in the second flow path is maintained to the upper than a second higher preset level. |
