A high pass muffler for a pneumatic tool that allows for high pass through of exhaust air. The muffler dampens noise generated by the exhaust air by incorporating channels in walls of the muffler that act as Helmholtz resonators.

Disclosed is a removable aftermarket exhaust adapter for a walk behind blower. The adapter includes a housing with a top-side, a left-side, a right-side, a front-side, a rear-side, and a bottom-side, the rear-side defining a rear-side opening and the bottom-side defining a bottom-side opening. The bottom-side is parallel to the top-side. The right-side is parallel to the left-side. The front-side is rounded to form a truncated j-shape from the top-side to the bottom-side. The left-side and right-side define a triangular shape void where the rear-side meets the bottom-side. And the rear-side opening is in fluid communications with the bottom-side opening. In one example, the top-side includes at a plurality of holes for accepting fasteners therethrough. The housing is fabricated from a composite material, plastic, metal, or a combination thereof.

A high pass muffler for a pneumatic tool that allows for high pass through of exhaust air. The muffler dampens noise generated by the exhaust air by incorporating channels in walls of the muffler that act as Helmholtz resonators.

Catalyst articles comprising palladium and related methods of preparation and use are disclosed. Disclosed is a catalyst article comprising a first catalytic layer formed on a substrate, wherein the first catalytic layer comprises palladium impregnated on a ceria-free oxygen storage component and platinum impregnated on a refractory metal oxide, and a second catalytic layer formed on the first catalytic layer comprising platinum impregnated on an oxygen storage component and rhodium impregnated on a zirconia-coated or yttria-coated alumina. The palladium component of the catalyst article is present in a higher proportion relative to the other platinum group metal components. The catalyst articles provide improved reductions in NOx in exhaust gases, particularly after lean-rich aging.

Disclosed is a removable aftermarket exhaust adapter for a walk behind blower. The adapter includes a housing with a top-side, a left-side, a right-side, a front-side, a rear-side, and a bottom-side, the rear-side defining a rear-side opening and the bottom-side defining a bottom-side opening. The bottom-side is parallel to the top-side. The right-side is parallel to the left-side. The front-side is rounded to form a truncated j-shape from the top-side to the bottom-side. The left-side and right-side define a triangular shape void where the rear-side meets the bottom-side. And the rear-side opening is in fluid communications with the bottom-side opening. In one example, the top-side includes at a plurality of holes for accepting fasteners therethrough. The housing is fabricated from a composite material, plastic, metal, or a combination thereof.

The temperature of exhaust gas discharged from a compact air-cooled engine used as a power source for an engine-driven working machine is reduced. An engine has a muffler mounted directly to the exhaust opening of the cylinder, and a resin muffler cover covering the muffler. An exhaust gas restriction member is provided to a wall surface of the muffler, and two exhaust passages serving as outlets for exhaust gas are formed in the exhaust gas restriction member. The exhaust passages are arranged independent of each other, and the streams of discharged exhaust gas are discharged to be slightly separated from each other as the streams flow away from the exhaust openings. The separated streams of discharged exhaust gas form a negative pressure space between the streams promoting the introduction of a cooling air stream into the negative pressure portion. Thus, the temperature of the exhaust gas can be reduced.

An internal combustion engine includes an engine block including a cylinder and a muffler assembly configured to receive exhaust gases from the cylinder. The muffler assembly includes a housing defining an interior volume and including an exhaust inlet and an exhaust outlet, and a baffle assembly positioned within the interior volume. The baffle assembly includes a plurality of chambers in fluid communication with each other. The plurality of chambers are in fluid communication with the exhaust inlet and the exhaust outlet so that the plurality of chambers are configured to cause exhaust gases to be directed through the muffler assembly from the exhaust inlet to the exhaust outlet through four passes in the baffle assembly before exiting through the exhaust outlet.

An extraction apparatus (10) adapted to capture exhaust gas emitted by an internal combustion engine and to dilute the exhaust gas by mixing with air and also cool the exhaust gas. The extraction apparatus (10) has a first flow path (31), second flow path (32), and third flow path (33). The first flow path (31) extends between inlet (35) and an outlet (37) for air flow from the inlet to the outlet. The second flow path (32) receives exhaust gas emitted from the engine and delivers it into the first flow path (31) for mixing with an air flow along the first flow path. The third flow path (33) delivers water for mixing with the air flow. The arrangement is such that there is confluence of air, exhaust gas and water to provide a fluid mixture for discharging through the outlet (37). The exhaust gas is cooled using the cooling effects of the air and also the cooling effects of water in heat exchange relation with the exhaust gas prior to mixing of the exhaust gas with the air. There is also cooling of the mixture of exhaust gas and air using the cooling effects of water in heat exchange relation with the mixture, and also cooling by injection of water into the air. The various flow paths are configured for the requisite heat exchange relation.

An exhaust purification system includes an exhaust passage. Exhaust gas flows through the exhaust passage. A burner is arranged in the exhaust passage. A combustion space for fuel in the burner is a part inside the exhaust passage. A NOx adsorbent is located downstream of the combustion space in the exhaust passage. The NOx adsorbent adsorbs nitrogen oxide contained in the exhaust gas. A selective reduction catalyst is located downstream of the NOx adsorbent in the exhaust passage. An adding valve is located between the selective reduction catalyst and the combustion space in the exhaust passage. A connection passage is connected to the adding valve. Urea water flows through the connection passage toward the adding valve. A part of the connection passage runs through the combustion space.

A portable flexible fuel generator, having an engine, includes: a cylinder and a spark plug in the cylinder, a primary fuel tank fluidly connected to the cylinder, an air intake path fluidly connecting atmosphere to the cylinder, a start module including a starting fuel tank holder and a starting fuel line, where the starting fuel line is fluidly connected to the air intake path, a coolant path which provide a flow path for coolant to cool the cylinder, and a thermal controller along the coolant path. Furthermore, the engine has full cylinder cooling.