DISPENSING METHOD AND APPARATUS

摘要

A method and apparatus for metering and dispensing an active ingredient, such as an insecticide, fumigant, fertilizer or room freshener. The active ingredient is placed in a container (6) and a pressurised propellant is subsequently introduced from a source (1) via conduits (3, 9). The propellant serves to absorb the active ingredient which is dispersed from the container via conduit (5) through a dispensing outlet (8) so that the active ingredient is dispersed in an airborne dispersion. In an ejector (4), a pressure differential is created across a propellant inlet port (4a) which is sufficient to draw the active ingredient from the active ingredient container (6) but is less than the pressure differential required to cause a cooling effect in the mixing chamber (4) and is less than that pressure differential that gives rise to an erratic dispersion of the active ingredient from the dispensing outlet (8). The system is particularly suitable for the spraying of insecticides into large spaces such as warehouses and supermarkets.