Patent attributes
An air powered vacuum apparatus for use in an air vacuum excavation system creates a fluid flow under vacuum and reduces the sound level of the exhausting air. The apparatus comprises an injector assembly and a container for collecting spoil, i.e., dirt, sand, gravel, etc. drawn in from the excavation site. The vacuum is produced by an injector and a supersonic nozzle assembly in fluid communication with the container. The injector has converging, straight and diverging sections, and the supersonic nozzle assembly extends into the converging section. The supersonic air ejected from the nozzle assembly mixes with the air drawn up from the container, and the air mixture travels through the diverging section and out of the injector assembly and creates a vacuum in the container.