Air flow balancing device

Claim 1

An improved air-flow balancing assembly for directly making measurements of the rate of flow of non-laminar exhausts of air from diffuser ports, such as room heating or cooling vents or the like, wherein the normal path of flow of air into the room from the diffuser is an uncontained, non-directional flow, comprising a lightweight, portable convergent air collection chamber having a continuous surface defining first and second openings, said first opening constituting a mouth of such dimensions as to encompass in overlapping relationship each such air diffuser against which said portable collection chamber is held to collect all the air discharged therefrom during the period in which the flow from each such diffuser is measured, said second opening defining a throat of a smaller known area, a neck of lightweight material connected to said convergent air collection chamber at such throat, said neck having a crosssectional area equal to that of such throat, air-flow straightening means of lightweight material and of substantially open form for minimizing the resistance to air flow therethrough, said air-flow straightening means having a cross-sectional area equal to that of said neck and being positioned within said neck for achieving generally laminar flow of the air pasSing therethrough, and means located downstream from said air-flow straightening means for making an average total pressure traverse across the entirety of said known cross-sectional area of said neck.