| 摘要 |
<p>The sleeve lifter consists of a cylindrical or slightly conical inner tube, spaced from and surrounding the spindle shaft, and an outer tube surrounding the inner one. The latter is connected at the bottom to the wharve, on which the outer tube rests with play by means of a shock absorber. The upper end of the inner tube is freely mounted about the spindle shaft and connected to the upper end of the outer tube by means of a resilient shock absorber.</p> |
