STROEMNINGSFOELER, SOM REAGERER PAA FLUIDUMSTROEMMER INNENFOR ET OMRAADE FRA OVER ET PAA FORHAAND BESTEMT MAKSIMUM OG SOM IKKE REAGERER PAA FLUIDUMSTROEMMER UNDER OMRAADET

摘要

A flow sensor is provided, responsive to fluid flows within a range from above a predetermined minimum to below a predetermined maximum, to indicate that flow is within that range and the minimum flow has been exceeded, but nonresponsive to fluid flows below the predetermind minimum or above the predetermined maximum, to avoid giving a false indication of fluid flow, comprising a flow-responsive valve and a differential pressure indicator.