| 摘要 |
<p>The helical balance screws which compensate for the weights of the drawing board are clamped to a movable part of the apparatus and to a fixed stand by holding members, of which at least one has the inner and outer threaded adjustment nut, so that the inner thread engages with a screw spindle and the outer thread engages with the pitch of the spring. The length of the spiral springs, which is effective for compensating the weight, can be adjusted by simply turning the adjusting nut outside the drawing board apparatus, so that the spring characteristic of the compensating spring can be adjusted infinitely and adapted to different weights.</p> |
