SHELTER Russian patent published in 1995 - IPC

FIELD: making of working positions protected against dust. SUBSTANCE: passage areas of air-admitting holes of grid of delivery and exhaust ducts of working zone in the sections whose width is equal to 1/5 to 1/3 of the distance between top of working bench and lower edge of partition in the direction perpendicular to partition plane which exceeds passage area of holes of the remaining part of delivery and exhaust ducts by 2 to 3 and 3 to 4 times, respectively. Delivery duct of clean zone is provided with delivery duct of air screen adjoining its end opposite to partition and communicating with delivery duct of clean zone before filter. Delivery duct of air screen is provided with cellular grid having width equal to 1/10 to 1/12 of width of cellular grid located in clean zone. Part of cellular grid of air screen delivery duct adjoining the cellular grid of clean zone delivery duct has width which is equal to 70 to 80 percent of total width of cellular grid in air screen delivery duct. Passage area of each hole of cellular grid is less by 3 to 4 times as compared with each hole of remaining portion of grid in the duct of air screen. EFFECT: enhanced reliability. 2 cl, 1 dwg