摘要 |
A vacuum tube lifting device includes a lifting hose having a first end for attaching the hose and a second end for connecting elements disposed to couple the hose to a load, the hose being for connectable to an adjustable vacuum source and a control unit disposed to adjust the pressure inside the hose via input signals for achieving an extending or contracting shifting movement of the hose for shifting of a load. The device includes an arrangement for measuring a parameter proportional to the momentary length of the hose or proportional to a change in the momentary length of the hose, and to emit to the control unit at least a first signal, used by the control unit to obtain an actual value, and to automatically adjust the vacuum source for adjusting the length of the hose to a desired target value starting out from the actual value. |