| 摘要 |
PROBLEM TO BE SOLVED: To synchronize the operating strokes of a plurality of hydraulic cylinders of a hydraulic knockout device with a simple constitution.SOLUTION: A first hydraulic pipe 15a is provided, which communicates a secondary hydraulic chamber 13b of one hydraulic cylinder 13 of two hydraulic cylinders 13, 14 having the same cross-sectional area of a hydraulic knockout device 10 with a primary hydraulic chamber 14a of the other hydraulic cylinder 14. When the hydraulic cylinder 13 is operated by supplying hydraulic oil to the primary hydraulic chamber 13a, the hydraulic oil to be discharged from the secondary hydraulic chamber 13b is supplied to the primary hydraulic chamber 14a of the hydraulic cylinder 14. The hydraulic cylinder 14 is naturally operated at the synchronized stroke to the hydraulic cylinder 13 only by supplying the hydraulic oil from a pump 18 to the primary hydraulic chamber 13a of the hydraulic cylinder 13. |
