| 摘要 |
The invention relates to a device in telescopic jibs in order to mount the telescopic parts one inside the other. In one embodiment with three telescopic parts (2, 3, 4), the centre part is designed as a tube with two diametrically opposite H-section bars (5) which have U-shaped channels, turned to the inside and outside, for accommodating rollers (10) which are arranged on the outer or inner tube. The bearing journals of the rollers carry sliding-bearing cushions (12) which interact with the surfaces of the channel webs. The roller bearings are arranged in such a way that they absorb the vertical component of the lifting forces exerted on the jib, whereas the sliding bearings are designed in such a way that they absorb the forces which are essentially at right angles to the vertical forces. One or more of the tubes (2, 3, 4) can consist of several components (3a, 3b) which are connected to one another in one piece by the H-section bars or alternatively by bars carrying the rollers (10).
<IMAGE>
|
