Patent ID: 7676965

Claim:
An air powered vacuum apparatus for use in an air vacuum excavation system, comprising: a container for drawing in and collecting spoil; a rigid suction tube and flexible hose assembly in communication with an interior of the container for drawing spoil and air into the container; and an injector assembly connected to and in communication with the container and with a supply of compressed fluid configured to convert the compressed fluid into supersonic fluid and then into subsonic fluid and to create a vacuum for drawing the spoil into the container, wherein the injector assembly comprises: a conduit having a fluid inlet in communication with the container and adapted to be in fluid communication with the compressed fluid supply, a supersonic nozzle assembly connected to compressed air supply for using the compressed fluid and ejecting supersonic fluid, and an injector associated with the supersonic nozzle assembly and the conduit, comprising at least a converging section, a straight section and a diverging section, wherein the supersonic nozzle assembly is positioned inside the converging section of the injector, wherein the straight section of the injector acts as a mixing chamber for mixing the supersonic fluid from the nozzle assembly with the fluid traveling from the container, wherein the conduit has a straight length that extends beyond the diverging section of the injector for the reduction of the sound level of fluid being ejected from the diverging section of the injector of the injector assembly, and wherein the rigid suction tube and flexible hose assembly and the injector assembly are separately connected to the container.