HEIGHT-CONTROLLABLE BLACKBOARD FOR RAISING WHOLE BLACKBOARD, WHICH IS EASILY INSTALLED AND MANUFACTURED AT LOWER COSTS

摘要

PURPOSE: Provided is a height-controllable blackboard, which controlles easily the height of a main blackboard, to be easily setup, to reduce manufacturing costs by reducing the number of parts and to raise the whole blackboard by strengthening the function of an auxiliary blackboard, thereby improving the efficiency of lecture. CONSTITUTION: The height-controllable blackboard comprises a main blackboard(1) to be setup for controlling the height; both-side auxiliary bulletin boards(2) adjacent to both sides of the main blackboard(1) and having a bottom side fixed on the wall, an opening side toward the main blackboard, and a receiving space inside; both-side auxiliary blackboard(3) inserted to be drawn on both auxiliary bulletin boards(2); two lifting rods vertically setup behind the main blackboard(1); two lifting bush with two connection fixing ribs; two fixing angles connected with the fixing ribs and attached to the wall; a number of a static load spring unit formed on the upper of the lower member of the main blackboard(1); and a stopper formed on the lower member of the auxiliary bulletin board.