Patent ID: 6837396

Claim:
A valve assembly that is suitable to dispense a chemical from an aerosol container that has a first region with a gas propellant and a second region with an active chemical, the valve assembly being of the type that can automatically iterate between an accumulation phase where the gas propellant is received from the container, and a spray phase where the active chemical is automatically dispensed at intervals, the valve assembly comprising: a housing mountable on an aerosol container; a movable diaphragm associated with the housing and being biased towards a first configuration, wherein the diaphragm is linked to a stem to move therewith, wherein the stem carries a seal surface and defines a valve outlet, and wherein the seal surface prevents active chemical from flowing through the valve outlet when the diaphragm is in the first configuration; an accumulation chamber inside the housing for providing variable pressure against the diaphragm; a first passageway in the housing suitable for linking the first region of the aerosol container with the accumulation chamber; a second passageway linking the second region with the valve outlet; whereby when the pressure of gas propellant inside the accumulation chamber exceeds a specified threshold the diaphragm can move to a second configuration where the seal surface is translated to permit active chemical to spray from the valve assembly.