WALL-SIGHT ARCHITECTURAL BLOCK

摘要

FIELD: construction engineering. SUBSTANCE: this relates to protection of building objects. Wall-sight block has upper sight portion and metal shield which is extendable from internal space by means of rope-and-pulley system. System has ropes which by their one ends are attached to ends of upper edge of metal shield. Each rope at its side by other end is reeved through pulley and connected with lever. Turning of this lever makes metal shield moving upwards. EFFECT: high efficiency. 4 dwge