| 摘要 |
The device has a support (9) fixed at a vertical upright (2), and a nut (12) blocked in rotation to the interior of the support. An acme screw thread (13) is arranged on an output axle (8) of a drive shaft (4) and permits to drive the nut in translation, and a compression spring (14) is arranged around the output axle, where a free space is created between a side of the nut and a side opposite to the compression spring. |
