| 摘要 |
A device for turning rotary motion into translatory motion, which device comprises at least three concentrically arranged threaded elements (2, 3, 4, 5). An externally threaded first element (2) is in engagement with an internally threaded second element (3). The second element (3) is furthermore provided with external screw thread (15), which is in engagement with an internally threaded third element (4). The second element is tubular, whereby the internal and external screw threads have been provided simultaneously by hydromechanical deformation of a metal tube. |
