| 摘要 |
A blackboard raising/lowering device of the present invention is a blackboard raising/lowering device capable of raising or lowering a blackboard frame (78), the device comprising: a plurality of link arms (31, 32, 65) hinge-coupled to each other; screw shafts (35, 66) screw-coupled with at least one link arm among the plurality of link arms (31, 32, 65) so as to raise/lower at least one of the link arm; and a motor (40) for driving the screw shafts. Accordingly, the present invention: enables a user to safely and conveniently operate a terminal box since an entire blackboard frame, which is heavy, having an integrated structure of the blackboard and various functions is provided to be highly efficient and to have a reduction in noise according to the operation thereof; and has a simple structure so as to be easily produced. |
