| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a hydraulic cylinder for restraining generation of a jet sound. <P>SOLUTION: This hydraulic cylinder has a piston 40 for defining a driving pressure chamber 5 and a cushion pressure chamber 6 in a cylinder tube 10, an air chamber 7 defined inside a hollow piston rod 20, an orifice 22 for guiding to the air chamber 7 an operating liquid of the cushion pressure chamber 6 contacting in extension operation, a check valve 8 for returning the operating liquid of the air chamber 7 to the driving pressure chamber 5 as a pressure difference between the air chamber 7 and the driving pressure chamber 5 rises to a predetermined value or more, and a valve housing 80 for storing this check valve 8. A flow restriction gap 24 is defined between an outer peripheral surface 83 of the valve housing 80 and an inner peripheral surface 23 of the piston rod 20, and the operating liquid ejected from the orifice 22 in the extension operation flows into the air chamber 7 through the flow restriction gap 24. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
