Induction air cleaner for a lawn mower engine

Claim 1

The combination comprising, a lawn mower housing including thereunder a rotatable air impeller for producing an air cushion supporting the lawn mower housing during operation, a combustion engine mounted to rotate said impeller, a carburettor disposed on said engine having an opening for receiving air, an air inlet port in said housing through which said impeller sucks air downwardly for said air cushion, a filter housing connected to said carburettor to pass air into said opening, a porous filter element in said filter housing through which air flows to said carburettor through said opening, a further housing comprising a closed end cylindrical chamber having elongated tangential air inlet openings therein adjacent the closed end and an induction tube extending coaxially therein, structure on said further housing engaging the filter housing to direct air thereto through said induction tube, means disposed to receive air flow outside the coaxial position of said induction tube defining an air flow path from said tangential openings in said further housing to said inlet port thereby causing said impeller to suck air into said tangential air inlet openings causing air flowing through said further housing to define a cyclone action with a central vortex about the cylindrical chamber axis, and said induction tube defining a single air inlet path to said carburettor opening positioned coaxially within said further housing thereby receiving a smaller amount of the air introduced into said tangential openings only from the cleaner air at the central portions of said vortex, whereby air is received from the elongated tangential air inlet openings for passage of a smaller portion of the air having dirt removed therefrom by cyclone action to said induction tube with the remainder and at least a substantial portion of the dirt therewith passing to said air inlet port in the lawn mower housing.