Engine air cleaner - noise reducer

Claim 1

An air inlet housing for an internal combustion engine having an air induction system, comprising an enlarged volume shell-type housing having walls defining the housing and a snorkel-like air inlet tube extending through an opening in one of the walls into a portion of the housing and an air outlet through another wall of the housing adapted to be connected to the engine induction system for the induction of air thereto, the inlet tube having a volume small relative to the enlarged volume of the housing whereby the housing constitutes an expansion chamber, the relative smaller volume of the inlet tube to the larger volume of the expansion chamber causing a sudden expansion in area as the air exit from the tube into the expansion chamber, and a conical-like engine induction noise reducing flow controlling insert coaxially positioned in the inlet tube, the insert being shaped to have apex and base portions situated upstream and downstream, respectively, in the tube, whereby the induction of air by the engine through the inlet tube increases the velocity and lowers the pressure thereof upon passage past the insert for the flow of air into the expansion chamber and therefrom into the engine in an efficient manner, the engine induction system passing acoustical waves into the large expansion chamber to be dissipated therein, any passage therefrom towards the inlet tube flowing against the base portion reflecting the waves back into the expansion chamber to be broken-up and dissipated therein, the inlet tube and outlet each have an axis so located that the axis of the outlet from the chamber is located essentially at right angles to the axis of the inlet tube providing greater reflection of the acoustical waves off the walls of the expansion chamber and absorption of the acoustical energy therein.