| 摘要 |
<p>The present invention relates to jacks, and particularly to telescopic jacks. According to the invention, the jack (10) has a cylinder (10A) provided with coaxial tubular elements (11), (12), (13), the displacements of which are limited by front and rear dead center means. The front dead center means (50) being set, in a retracted position of said elements, within a first multi-stage depression (43) provided on a first tubular element, providing a minimal play between this tubular element and an adjacent tubular element, whereas, in an advanced position of said first tubular element, the front dead center means (50) abutts partially against said depression and partially against a second depression (40) provided therefor the adjacent tubular element. Application to telescopic jacks. </p> |
