CLASSROOM BLACKBOARD

摘要

FIELD: technical aids for teaching and informing, namely with use of chalk recording. SUBSTANCE: blackboard includes one or several panels with counterweights and a rope-pulley system, two tubular guides. The counterweights are mounted inside of the guides. A central panel is secured by two pairs of brackets, connected with slides, embracing the guides. EFFECT: enhanced structure of the blackboard, providing its enhanced serviceability. 3 cl, 3 dwg