| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a hydraulic pressure control circuit which automatically exchanges operating water in a hydraulic control circuit with new operating water, the hydraulic control circuit constituting a closed circuit configured by connecting a head-side chamber and a cap-side chamber of a dual rotary pump and a single rod cylinder by extending/retracting the single rod cylinder, and enhances operation efficiency without stopping the single rod cylinder. <P>SOLUTION: The hydraulic control circuit is configured by connecting a head-side chamber 8B of the single rod cylinder 5 with a first port 3 of the dual rotary pump 2 using a first passage 9, and connecting a cap-side chamber 8A of the single rod cylinder 5 with the second port 4 of the dual rotary pump 2 using a second passage 10. The first passage 9 is connected to a supply source which supplies the new operating water using the third passage 11, while the second passage 10 is connected to a discharge side using the fourth passage 13. A check valve 12 is arranged on the third passage 11 in a direction which allows for flow from the supply source side to the first passage 9, while a pilot operation check valve 14 is arranged on the fourth passage 13 in a direction which allows for flow from the discharge side to the second passage 10. <P>COPYRIGHT: (C)2013,JPO&INPIT |
