Crane with telescopic column - has extension by hydraulic jacks also able to swing column to horizontal position when not in use (SW 12.6.78)

摘要

The telescopic crane is mounted on a base with the outer member (4) of the column fixed by pivot bolts (3) to the structure (4). The inner member (5) of the column has a collar (9) which can be fixed to it by means of bolts. The column is swung to the vertical position and the inner member pushed upwards by the jack (6) to enable the lower end to rest on the ground. The bolts of the collar are removed and the collar dropped to a lower position and rebolted. The jack then raises the inner member to a still higher position where it is locked by the stop (14).