TELESCOPICALLY EXTENDING SHAFT

摘要

Telescopically extending shaft that comprises parts (1 - 3) conveying rotation movement and axial force and the extending and shortening of which shaft is achieved with the help of a power unit, such as a hydraulic cylinder (8) moving in one axial direction and the moveable, separate parts (1 - 3) of which shaft moving telescopically in relation to each other are arranged to move in an as such known way by using pulling elements (6); (7) and sheaves (26); (27) attached to the parts (1) and (2) adjusted in such a way that the first part (1) that can be moved straight with the help of a power unit (8) causes the movement of the second part (2) through the pulling element (6) and the sheave (26) attached to the first part and the sheave (27) attached to the second part (2) causes the movement of the third part (3) through the pulling element (7) starting from the first part (1). In order to retract the parts (1 - 3) of the shaft the arrangement comprises the first part (1) that can be pulled to a retraction direction with the help of the power unit (8) and comprises a pulling element (24) the first end of which is attached to the moveable part (25) of the power unit in which case the second end of the pulling element (24) is attached to the third part (3) in such a way that it first passes round the sheave (23) located fixed inside the shaft and then passes round the sheave (22) attached to the moveable part of the power unit (8).