| 摘要 |
PROBLEM TO BE SOLVED: To improve steering follow-up performance at the time of positive input by steering operation in a steering damper to reduce shock at the time of reverse input such as kick-back from the side of steering wheels. SOLUTION: A right and a left cylinder passage 3, 4 to connect a flow passage selector valve CV to selectively connect a pump P and a tank T to power cylinder right and left chambers CL, CR to the power cylinder right and left chambers are provided. A right and a left variable throttle valves 6, 8 are provided in the midway of the respective cylinder passages 3, 4. A right and a left pilot operation check valves 8, 9 connected in parallel to the respective variable throttle valves 6, 8 to connect each chamber of a power cylinder to the tank for prohibiting flow on the return side are provided. To these pilot operation check valves 8, 9, pilot pressure passages 8a, 9a to introduce hydraulic pressure in the other cylinder passage are connected, and the pilot operation check valves 8, 9 are composed to be capable of opening to obtain flow on the return side from each chamber of the power cylinder to the flow passage selector valve side. |
