Precleaner assembly

In a vehicle, a precleaner assembly for the engine air intake system for separating particulate material from the entering air comprising a housing having an inlet and a outlet facing a direction other than the direction faced by said inlet, said housing defining a flow path between said inlet and said outlet and having a converging conduit section having a bend communicated with the inlet and turning the air communicating through the inlet into the direction faced by the outlet, and a diverging conduit section communicated with an outlet conduit section, wherein the entrance to said diverging conduit section presents a smaller cross-sectional area than the cross-sectional area at the exit of said diverging conduit section so that air communicated through the diverging conduit section is expanded, the exit from the converging conduit section presenting a smaller cross-sectional area than the entrance to the converging conduit section so that air communicated through the converging conduit section is compressed, the exit from the converging conduit section and the entrance to the diverging conduit section joining to define a throat whereby fluid entering said inlet is compressed by said converging conduit section to a maximum pressure level at said throat, means in said diverging conduit section for turning the fluid into a spiral path so that centrifugal forces generated by movement of the particulate material in said spiral path urge said particulate material toward the wall of said housing, said turning means having an inlet, the inlet of said turning means being located substantially at said throat, and means for ejecting from said outlet conduit section the portion of the fluid adjacent the wall of said outlet conduit section in which said particulate material is concentrated, the rest of said air being communicated in an axial direction to said outlet.