Patent ID: 9269248
Filing Date: 2016-02-23
CPC Classification: A62C,B05B,G08B

Claim Text:
1. An aspirated smoke detector comprising: a smoke detection chamber; an inflow duct with at least one fluid inflow port; a blower that draws or sucks smoke from a fire within a region through the inflow duct and into the smoke detection chamber; and a thermally responsive element, adjacent to the inflow port, that responds to heat or combustion products from the fire, wherein the element alters an inflow area of the port by increasing a relative area of the input port in response to an adjacent ambient atmosphere, thereby offsetting dilution of smoke due to air entering the inflow duct from other inflow ports which are not near the fire, and wherein the increase of the relative area of the input port occurs only at the inflow port relatively closest to the fire.