| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a hydraulic jack capable of providing large thrust while keeping a sealing property. <P>SOLUTION: A main recessed portion 12 and a sub recessed portion 13 having a diameter smaller than that of the main recessed portion 12 are formed on a body 11. A main plunger 14 is integrated in the recessed portion 12 to structure a main cylinder portion A, and a sub plunger 15 is integrated in the sub recessed portion 13 to structure a sub cylinder portion B. A sealing member 9 is interposed between the recessed portions 12, 13 of the cylinder portions A, B and the plungers 14, 15. Low pressure is supplied into an oil chamber 18 of the main cylinder portion A, and high pressure is supplied into an oil chamber 19 of the sub cylinder portion B. <P>COPYRIGHT: (C)2003,JPO</p> |
