Abstract: A muffler has a main body, and an inner shell spaced radially inwardly of the main body by an annular volume therebetween. The inner shell has an internal volume radially inward of the annular volume. The muffler has primary and secondary parallel paths therethrough, with the primary path extending through the internal volume, and the secondary path extending through the annular volume.

Abstract: An exhaust aftertreatment device (10) includes an aftertreatment element (24) for treating internal combustion engine exhaust, an injector (26) for injecting chemical species mixing with the exhaust prior to reaching the aftertreatment element, and a turbulator (36) turbulating the exhaust to enhance the noted mixing. In a desired combination, a two-stage integrated perforated tube combination structure includes a turbulent mixing tube (38) disposed in an acoustic tube (40) and concentrically surrounded thereby.

Abstract: An exhaust aftertreatment device (10) includes an aftertreatment element (24) for treating internal combustion engine exhaust, an injector (26) for injecting chemical species mixing with the exhaust prior to reaching the aftertreatment element, and a turbulator (36) turbulating the exhaust to enhance the noted mixing. In a desired combination, a two-stage integrated perforated tube combination structure includes a turbulent mixing tube (38) disposed in an acoustic tube (40) and concentrically surrounded thereby.

Abstract: A vertical exhaust system for an internal combustion engine that incorporates a provision for receiving and trapping water, such as rain, that may enter the open upper end of the exhaust conduit. The exhaust system includes a vertical outer body and a perforated tube is disposed within the outer body and spaced therefrom to provide an annular chamber therebetween. A plug or closure is secured within the tube and is spaced from the lower end of the tube, thus closing off the tube. An annular flange interconnects the inner tube with the outer body and is spaced longitudinally below the plug, to thereby enclose the lower end of the chamber. A drain hole extends through the outer body and connects the chamber with the exterior. The drain hole is spaced above the flange, so that the space between the flange and the drain hole comprises a trap to collect water that may enter the upper end of the exhaust system.

Abstract: An exhaust muffler having a protective shield to reduce noise radiation and to decrease the temperature of the exhaust gases being discharged from the muffler. The muffler is composed of an outer body enclosed at its ends by flanges, and an outer insulated shell is spaced outwardly from the body and is connected to the peripheral edges of the flanges. Holes are provided in the flanges which communicate with the space between the shell and the body so that air is drawn by convection through the space between the outer body and the shell. A tubular member is spaced outwardly of the outlet pipe of the muffler and the outer end of the tubular member projects outwardly beyond the outer end of the outlet pipe.

Abstract: An exhaust muffler comprising an outer body having open ends which are enclosed by heads. An exhaust gas inlet tube is mounted in an opening in one head, while an outlet tube is mounted in an opening in the opposite end. The adjacent ends of the inlet and outlet tubes are spaced apart within the body. A baffle is secured to the inner end of the inlet tube, closing off the tube, and the peripheral edge of the baffle is spaced from the body to provide an annular passage. Exhaust gas and sound energy entering the inlet pipe are directed outwardly by the baffle through perforations in the tube, and the gas then passes through the annular passage and is discharged from the body through the outlet tube.

Abstract: A spark arrestor aspirating muffler for an internal combustion engine which comprises an outer body or housing having an exhaust gas inlet in one end and a gas outlet in the opposite end. Located immediately upstream of the outlet is a venturi and air is drawn into the throat of the venturi through an air inlet tube connected to a pre-cleaner for the engine. A baffle plate containing a series of louvered openings is positioned upstream of the venturi and the exhaust gases entering the gas inlet conduit are swirled outwardly as they pass through the louvered openings and are discharged through the venturi. The solid particles in the swirling exhaust gas are thrown outwardly and move along the inner surface of a tubular member which is secured to the downstream side of the baffle and are collected in a collection chamber.