DEVICE MEASURING AIR PERMEABILITY Russian patent published in 2000 - IPC

FIELD: examination of properties of concrete and other porous materials for air permeability. SUBSTANCE: device measuring air permeability includes working chamber with hole for air tapping, vacuum gauge, gear creating vacuum, indication unit, rarefaction relief valve, chamber-receiver. Indication unit incorporates air distributor, differential manometer and comes in the form of branch pipe divided in center by narrowing hole. First and second holes joined leak-tight to proper inlet holes of differential manometer are made on both sides of narrowing hole. Outer hole of working chamber is connected to first end of branch pipe of air distributor and second end of this branch pipe is connected to chamber-receiver that carries vacuum gauge and rarefaction relief valve. Gear creating vacuum has T-shaped branch pipe and hollow chamber made of elastic material, for instance, rubber pear linked to central part of T-shaped branch pipe. Two other ends of it are fitted with valves. One of valves is connected to chamber-receiver. Surface of working chamber bordering on tested object is divided into external and internal parts with use of annular groove connected to hole for air tapping. EFFECT: simplified design of device, reduced mass and size characteristics, exclusion of need for power supply source and expanded technical capabilities while measuring air permeability of wide range of objects under real conditions. 2 cl, 4 dwg