| 摘要 |
<p>A novel jackable prop or stand is provided herein. It includes a base including a transverse plate and a pair of widely spaced apart forwardly projecting feet. A pair of spaced apart, upstanding posts are secured to the prop, e.g. either to the transverse plate at the region of the forwardly projecting feet or due directly to an associated foot. A freely vertically movable lifting frame is slidably mounted on the posts. m e lifting frame includes: (i) a pair of bushing, each being freely slidably mounted on a respective post; (ii) a transverse bar interconnecting the bushings; (iii) a forwardly projecting lifting arm e.g. projecting forwardly from each of the bushings, or from the transver bar; and (iv) engagement means on associated with the transverse bar to enable the bar, and hence the lifting frame, to be raised and e.g. pins adapted to be inserted through aligned holes in the posts and bushings means for holding the lifting frame at a predetermined raised vertical position on each associated post after the lifting frame has been so raised. The jackable prop is used with a mechanical or hydraulic jack which is adapted to be removable disposable between the base and the engagement means for raising the lifting frame relative to the base. A safe, reliable, rugged and versatile prop or stand is thus provided.</p> |
