| 摘要 |
A device for transferring a rotational motion into a longitudinal movement or vice versa. The device comprises a cylindrical shaft (1), a sleeve (2) enclosing the shaft and displaceable along and rotatable relative thereto. A cage (3) is mounted between the sleeve and shaft for axial movement with the sleeve as a unit. A plurality of rolling bodies (4) are mounted in elongated apertures in the cage and are arranged during operation to roll in a closed track around the shaft. The track has a helical portion and a recirculation portion. The rolling bodies contact the shaft and the sleeve in the helical portion and are axially moveable in the recirculation portion. Cam profile members (5, 6) are arranged at the ends of the cage for actuating the rolling bodies in the recirculation portion. The rolling bodies are arranged in the apertures in the cage in such a manner that their axes form an angle to the cylindrical shaft, this angle corresponding to the pitch angle of the helical form of the helical track portion. |
