lifting device for heavy loads has length-adjustable telescopic tube whose tube sections move inside one another without seals raised and lowered by signal device locking and unlocking of devices each tube section central hydraulic cylinder

摘要

The lifting device has a multi-part length-adjustable telescopic tube whose tube sections(3-7) are guided one inside the other without seals and are each provided with a device (9-13) for controlled locking and unlocking with an adjoining section and with the piston (14) of the central hydraulic cylinder (2). The piston is fitted with a signal device (16) to trigger the locking and unlocking processes in order to raise and lower the load platform provided at the top of the telescopic tube.