| 摘要 |
<p>The telescopically-extensible lifting mechanism is operated by a spindle drive and is used in mining for coal face support or in hoisting rigs and in commercial lorry construction. It has a spindle guided in a ball rotation nut. A pressure plate (4) of the lifting rig is arranged coaxially to the cage of the spiral nut, and supports the shoulder end of the nut. Slender rollers or a coiled tube (6) are arranged in the thread groove (21') of the cage (2) at the upper end, above the thread grooves filled with the balls (3). A bypass tube is provided to allow the balls to run from the upper to the lower end of the nut when the spindle is turned.</p> |
