Abstract: A muffler unit for a general-purpose engine includes a muffler (40) having a maze of sound-deadening chambers (101, 102, 103) defined therein and an inlet pipe (85) disposed inside the muffler. The inlet pipe has an open end (106) connected to an exhaust port of the engine via an exhaust pipe (43), a closed end (107) opposite to the open end, and perforations (108) provided near the open end and connecting an internal space of the inlet pipe and a first sound-deadening chamber (101). The closed end of the inlet pipe is exposed to the outside air, so that exhaust gasses are cooled when the gasses impinge on the closed end of the inlet pipe.

Abstract: An exhaust system comprises a muffler and a Helmholtz resonator. The muffler comprises an exhaust inlet aperture for receiving exhaust gas into the muffler, an exhaust outlet aperture for discharging exhaust gas from the muffler, and a resonator aperture. The Helmholtz resonator is at least partially external to the muffler and in acoustic communication with the resonator aperture. An associated method is disclosed.

Abstract: A muffler that inhibits reduction in engine performance and reduces exhaust noise volume includes a front chamber and an expansion chamber with a partition therebetween. A conduit passes through the expansion chamber. An upstream end of the conduit passes through the partition and opens in the front chamber. A partition wall is provided in a central section of the conduit. An outflow section upstream from the partition wall has a side surface in which outflow holes are formed that allow exhaust gas to flow out to the expansion chamber. An inflow section downstream from the partition wall has a side surface formed with inflow holes that allow exhaust gas to flow in from the expansion chamber.

Abstract: The invention relates to a silencer for an airborne sound conducting pipe system, including a housing enclosing an interior space, an inlet pipe having an outlet within the interior space, a bypass pipe branching off from inlet pipe within the housing and having an outlet, a control element actuated by the gas flow and arranged downstream of bypass pipe on or in the inlet pipe, and at least one outlet pipe having an inlet within the interior space. Furthermore, the interior space is acoustically unseparated in such a manner that the volume of the interior space loaded with the airborne sound is equal with opened and with closed control element.

Abstract: A silencer for an internal combustion engine includes a silencer housing formed by a pair of clamped housing members each having a substantially identical configuration relative to one another. The silencer housing has an intake port formed at a first end and an exhaust port formed at a second, opposite end. At least one separator is received in the silencer housing between and spaced apart from the first end and the second end. The at least one separator extends transversely across the silencer housing relative to a longitudinal length of the silencer housing.

Abstract: A muffler for an engine in oilfield applications has a tube with nozzles in its inlet section for spraying a mist of water from the well into the exhaust gases produced by the engine, so that a significant portion of the water is converted to water vapor and exits with the exhaust gases at the outlet of the tube. Vortex generators on the interior surface of the midsection of the tube create turbulence in the exhaust gases and water mist. A sump at the outlet section of the tube collects the remaining water and pollutants trapped by the water for subsequent disposal.

Abstract: The present invention generally relates to the attenuation of vacuum blower noise using a silencer. More particularly, the present invention relates to a low-cost, reliable and efficient silencer for reducing noise levels in adsorption-based gas separation plants from the discharge of the vacuum blower or from the feed blower inlet, to about the 90 dBA level or less, at the silencer opening to the atmosphere. The silencer includes at least one reactive chamber(s) to attenuate low frequency pulsations and at least one absorptive chamber(s) to attenuate noise at medium to high frequency noise.

Abstract: An apparatus and method for attenuating the sound generated by a single duct terminal unit in an HVAC (heating, ventilating, and air conditioning) system. The apparatus utilizes internal geometry to minimize noise due to air disturbances and aerodynamic effects within the apparatus.

Abstract: A noise reduction structure for a hybrid vehicle in which a cover covers at least part of an air intake system connected to an engine capable of giving power to a driving wheel, an exhaust muffler constituting part of an exhaust system connected to the engine, and an electric motor capable of giving power to the driving wheel. When at least part of the air intake system, the exhaust muffler constituting part of an exhaust system, and the electric motor is covered with the common cover, heat generated by the exhaust muffler is prevented from affecting the electric motor. The rotational axis of the electric motor extends in a longitudinal direction of a body frame and is disposed forwardly of the central position of the exhaust muffler extending in the longitudinal direction.

Abstract: A double-flow exhaust system for an internal-combustion engine, having exhaust-gas-carrying pipes and at least one muffler and catalyst housing. A separate end muffler is provided for each exhaust line, on which the end mufflers are both fluidically connected by at least one preferably mountable connection pipe.

Abstract: A muffler has a casing with a plurality of sound-muffling chambers, exhaust pipes that pass through at least two sound-muffling chambers and to pass through exhaust from an engine, a plurality of apertures provided in each exhaust pipe, and a plurality of valves provided in each of the apertures. In this muffler, the plurality of apertures are provided at the locations at which an exhaust flow from one aperture and an exhaust flow from another aperture do not interfere with each other. When there are two apertures, the apertures are provided at positions in the exhaust pipes at which the apertures do not face each other. For this reason, by avoiding interference between exhaust flows from the two apertures, it is possible to suppress an abnormal sound caused by the interference.

Abstract: Silencer of exhaust gases, in particular for motor vehicles, comprising an inlet opening (13) and a cylindrical coat (1) provided with an outlet pipe (29) at its opposing end, said cylindrical coat (1) has an internal division into at least four working sections (5, 6, 7, 8) containing axially arranged elements, especially suppression elements, expansion chambers, a whirl chamber, resonators and twirling, deflecting, and accumulating elements, confined with at least three crosswise arranged partitions (2, 3, 4), while the cylindrical coat (1) opposite to the outlet tube (29) is provided with an inlet section (10) freely encompassing its first working section (5) provided with inlet holes (18) of exhaust gases, said inlet section (10) being attached to the surface of the cylindrical coat (1).

Abstract: A muffler includes a case divided into three chambers by two baffles. The first chamber is closest to, and the third chamber is farthest from, the exhaust pipe. An inlet pipe has a first end connected to the exhaust pipe, and a second end in fluid communication with the third chamber. An outlet pipe expels exhaust and water from the first chamber to the exterior. A connecting pipe provides fluid communication between the first and third chambers. The second end of the inlet pipe is above the bottom interior surface of the outlet pipe. The inlet pipe may have holes in the second chamber, above the bottom interior surface of the outlet pipe. The connecting pipe may have holes in the second chamber. The baffles may have holes for the water to flow from the second and third chambers to the first chamber. Also, an exhaust apparatus utilizing the muffler.

Abstract: The present invention relates to an improvement muffler that includes an improved inlet configuration having first and second sequential chambers with a perforated central pipe passing longitudinally through a central region of both chambers for directing the exhaust gases into the third chamber in which the deflection element is deployed. Additionally, the partition separating the first and second chamber has a hole that enables some of the gas to pass from the first chamber into the second chamber not through the central pipe.

Abstract: A muffler for an internal combustion engine having a housing with an inlet end with an inlet opening formed for a flow of exhaust gases into the housing and an outlet end with an outlet opening formed for a discharge of exhaust gases from the housing; at least a first chamber, a intermediate and a last chamber sequentially arranged within the housing, the intermediate chamber containing a deflection element; a pipe passing longitudinally through the first chamber so as to open at its downstream end into the intermediate chamber, thereby directing the exhaust gases toward the deflection element; and a perforated pipe extending through the last chamber, the perforated pipe having an upstream opening into the intermediate chamber and configured to channel the exhaust gas to the outlet opening. A sound-attenuating material is deployed in at least one of the first chamber, the intermediate chamber and the last chamber.

Abstract: A silencer includes a smaller cylindrical member having a planar portion and a larger cylindrical member arranged to closely contact at least a portion of the outer circumferential surface of the smaller cylindrical member. The larger cylindrical member as seen in a direction orthogonal to its axis provides an oblate cross section having a major axis X and a minor axis Y and the smaller cylindrical member is arranged to have the planar portion traversing the major axis X of the larger cylindrical member.

Abstract: A muffler of a vehicle includes a first muffler body so as to form a first chamber, at least a second muffler body including a housing, one end portion opened and the other end portion closed, wherein one of the second muffler bodies is fitted into the other end portion of the first member to form a second chamber and the other second muffler bodies are fitted into each other through the one end portions in series to form third chambers if more than one second muffler bodies are assembled, an inflow pipe to connect the outside with the first, second and/or third chamber by passing the one end portion of the first muffler body, and an outflow pipe to communicate the first, second, and/or third chamber with the outside by passing through the other end portion of the last second muffler body.

Abstract: In order to make available an exhaust gas system for a combustion engine with an external housing, which contains at least one rear shell and one front shell, and with a catalyst chamber, in which at least one catalyst element is arranged, and with an exhaust gas duct, from which exhaust gas is conveyed from the catalyst chamber, said exhaust gas system including few components and being able to be produced cost-effectively and wherein harmful thermal stresses in the components of the exhaust gas system are largely avoided, the catalyst chamber also forms the exhaust gas duct. The catalyst chamber has at least two chamber halves, and the exhaust gas duct is provided materially uniform and in one piece in at least one chamber half.

Abstract: A muffler with enhanced seam strength construction, and method therefor, is provided by shell sidewalls having facing lips extending at an angled direction relative to afterfire explosive force along a lateral direction, such that outward lateral movement of the first sidewall is blocked by the second lip in the path of lateral movement of the first lip and such that outward lateral movement of the second sidewall is blocked by the first lip in the path of lateral movement of the second lip.

Abstract: An adjustable Helmholtz resonator assembly is provided having an active state and an inactive state. In the active state the Helmholtz resonator assembly is operable to attenuate pressure pulsations within air passing therethrough. In the inactive state the Helmholtz resonator assembly does not attenuate pressure pulsations within air passing therethrough. The Helmholtz resonator assembly is preferably configured to be mounted within an intake system of an internal combustion engine.

Abstract: A marine muffler comprises an elongate cylindrical housing having an inlet and an outlet and defining an internal volume partitioned, by an angularly disposed internal baffle, into a lower chamber in communication with the inlet and an upper chamber in communication with the outlet. A vertically disposed duct is insertably secured to the baffle to allow exhaust gas and exhaust cooling water to flow from the lower inlet chamber to upper outlet chamber. The exhaust duct may preferably be further adapted with internal structure forming a plurality of individual flow conduits or passages. The duct is preferably positioned such that a plurality of flow passage inlets are positioned in proximity to the lower cylindrical housing wall, with flow passage outlets positioned in proximity to the upper housing wall. The lower duct wall may further be adapted with sidewall apertures for improving exhaust flow dynamics therethrough.

Abstract: A rear muffler assembly for an internal combustion engine has a first and a second muffler through which exhaust gases flow and which are separated from one another. The first and second mufflers have in each case an exhaust gas delivery and discharge through an exhaust gas routing pipe issuing into an exhaust pipe which follows downstream and in which an exhaust gas shutoff flap which can be closed temporarily is disposed. The rear muffler assembly contains two exhaust gas routing pipes, the first exhaust gas routing pipe having within the rear muffler an issue orifice for exhaust gases positively emerging from the second exhaust gas routing pipe, with the exhaust gas shutoff flap closed, into which first exhaust gas routing pipe the exhaust gases from the internal combustion engine flow directly.

Abstract: A muffler includes a case divided into three chambers by two baffles. The first chamber is closest to, and the third chamber is farthest from, the exhaust pipe. An inlet pipe has a first end connected to the exhaust pipe, and a second end in fluid communication with the third chamber. An outlet pipe expels exhaust and water from the first chamber to the exterior. A connecting pipe provides fluid communication between the first and third chambers. The second end of the inlet pipe is above the bottom interior surface of the outlet pipe. The inlet pipe may have holes in the second chamber, above the bottom interior surface of the outlet pipe. The connecting pipe may have holes in the second chamber. The baffles may have holes for the water to flow from the second and third chambers to the first chamber. Also, an exhaust apparatus utilizing the muffler.

Abstract: A vehicle resonator structure and attachment method is provided and includes a resonator chamber that has a first intake tube and a first exhaust or outlet tube attached thereto. At least one of the tubes includes a projection that can be molded (e.g., via flash molding after the tube itself is blow molded) onto the tube. The resonator chamber can include upper and lower tube mount structures that can be hot plate welded and sandwiched onto the projection in the tube. Thus, the tube(s) is/are positively retained in position with respect to the resonator chamber such that the tuning of the resonator does not change due to fluctuations in geometry of the tube(s) and resonator chamber structure, and such that there is little or no vibration noise and/or possible damage that might result if the tube(s) were free to move with respect to the resonator chamber.

Abstract: An exhaust system for a motorcycle includes exhaust pipes extending from exhaust ports of an engine, a first muffler chamber for receiving the exhaust pipes, a second muffler chamber arranged parallel to and operatively connected with the first muffler chamber, and a silencer disposed in the second muffler chamber. The exhaust system is distributively arranged in a vehicle width direction such that the first muffler chamber is situated on a left side of a center line of the motorcycle defined along longitudinal direction of the motorcycle, and the second muffler chamber is situated on a right side of the center line. The first and second muffler chambers are disposed at a position below the engine. The exhaust gas from the engine is emitted outside the engine via, in sequence, the exhaust pipes, the first and second muffler chambers and the silencer.

Abstract: The present invention is directed to an improved dual phase muffler for the abatement of reduction of sound and emission pollutants such as hydrocarbons, carbon monoxide, and nitrogen oxides. More specifically, the muffler comprises a muffler casing, an inner chamber formed in the muffler, and a catalytically coated supported material contained within the inner chamber. The present invention is also directed to a catalytically coated metallic foam catalyst support, which optionally can be pre-coat with a metallic thermal arc sprayed layer.

Abstract: The present invention relates to a muffler for an exhaust system of an internal combustion engine, including a housing having at least one absorption chamber which is filled with an absorbent material that has an absorbent effect for airborne sound, a straight-through pipe that carries exhaust gas during operation of the muffler and passes through the housing, and at least one blind pipe that is connected at one end laterally to the straight-through pipe and is sealed at the other end. The blind pipe has a wall that is acoustically transmissive for airborne sound in an area running in the absorption chamber.

Abstract: Disclosed herein is a muffler of a scroll compressor. The muffler includes a first muffler having a pair of chambers defined above an outlet of a fixed scroll to communicate with the outlet and a gas passage hole formed at the center of an upper end thereof, and a second muffler located around the first muffler to be spaced apart from the gas passage hole of the first muffler and having a chamber including one or more guidance paths of the fixed scroll. The muffler can achieve reduction of operational noise, sufficient separation of oil contained in discharge gas, and efficient isolation between a discharge pressure inside the muffler and outside suction pressure.

Abstract: The invention relates to a muffler for an exhaust system of an internal combustion engine, consisting a housing having at least one exhaust inlet and at least one exhaust outlet and having at least two pipes at the inlet end or at the outlet end, at least one of which is switchable by a control device at least between an open state and a closed state and is acoustically coupled to a silencer system, such that the silencer system is active when the switchable pipe is opened as well as when it is closed and has a different damping characteristic when the switchable pipe is opened than when the switchable pipe is closed.

Abstract: A muffler is capable of sufficiently reducing flow noise, discharge noise, vehicle noise, and cabin noise, preventing a pressure loss, and improving output power. The muffler has a muffler body, an upstream pipe that opens in the muffler body, and a downstream pipe that opens in the muffler body. An opening is formed in a side wall of the downstream pipe in the muffler body. The opening consists of many small holes arranged in an elongated area extending in an axial direction of the downstream pipe.

Abstract: An automotive muffler includes an external tube consisting of a first widened portion, a first tapering portion, and a first narrow portion, the first widened section having a sealing wall with a through hole at the front end thereof; an internal tube consisting of a second widened portion, a second tapering portion, and a second narrow portion, the internal tube being disposed within the external tube, a plurality of vent holes being formed in the wall of the second widened portion; an internal guide tube consisting of a third widened portion, a third tapering portion, and a third narrow portion, the internal guide tube being disposed within the internal tube, a plurality of vent holes being formed in the wall of the third widened section that is disposed within the internal pipe; and a plurality of partitions interposed between the first widened section and the second widened section as well as between the second widened section and the third widened section.

Abstract: A muffler for an exhaust gas system of an internal-combustion engine has an exhaust gas inlet and a first flow pipe arranged inside the muffler and completely penetrating the muffler. A shut-off device is arranged in the first flow pipe, for the shutting-off and opening-up an exhaust gas tail pipe which is situated downstream of the muffler and is connected with the first flow pipe. A second flow pipe partially penetrates the muffler, and has an overflow path between the first and second flow pipes situated inside the muffler. The first and the second flow pipes are connected with the exhaust gas inlet by way of a branching element and the shut-off device is arranged upstream of the muffler in the first flow pipe.

Abstract: In an exhaust system, exhaust manifolds are connected to two banks provided in a V-type engine of a vehicle, respectively, to which front pipes each having a catalytic converter are connected to the exhaust manifolds, respectively. A muffler is provided at an exhaust downstream side of the exhaust pipes, and a rear pipe is further connected to the exhaust downstream side of the muffler. The front pipe has its rear end portion located near a through hole formed in the rear pipe. A path length of one of the front pipes from the bank to the muffler is made shorter than that of the other front pipe.

Abstract: A gas expansion silencer comprising an endpiece for being connected to a source of gas under pressure, and a low-pressure stage comprising two cylindrical portions respectively of smaller diameter and of larger diameter, the smaller-diameter portion being connected to the endpiece and the larger-diameter portion having gas outlet orifices, the low-pressure stage being entirely filled with a porous metal packing.

Abstract: To provide a muffler for a compact combustion engine, which is simple in structure and effective to sufficiently reduce the temperature of exhaust gases while avoiding contact with an external air, an exhaust guide passage 7 for communicating the exhaust gases (G) to a discharge port (63) is provided within an interior hollow of a muffler housing 6 defining an exhaust chamber (61) therein, and a side wall of this exhaust guide passage (7) is constituted by a portion (6W) of the muffler housing (6) and a duct wall (71) jointed to the muffler housing (6).

Abstract: A muffler suited for use in discharging exhaust gas from an engine. The muffler generally includes a housing that defines a muffler interior, an inlet aperture, and an outlet aperture. A baffle that defines a baffle interior is positioned to divide the muffler interior into an inlet space and an intermediate space. A first aperture is defined within the baffle to provide fluid communication between the inlet space and the intermediate space and a second aperture is formed within the baffle to provide for fluid communication between the intermediate space and the baffle interior. A flow guide is integrally formed with the baffle and is positioned to direct exhaust gas from the baffle interior through the outlet aperture.

Abstract: The invention is directed to an exhaust-gas muffler (1) of a handheld work apparatus driven by an internal combustion engine. The exhaust-gas muffler (1) includes a muffler housing (2) which includes an engine-end wall (3) having an inlet window (4) as well as an outlet (5). Attachment means (6) for fixing the exhaust-gas muffler (1) on the internal combustion engine are provided on the engine-end wall (3) in the region of the inlet window (4). The engine-end wall (3) is provided with a reinforcing sheet metal piece (7) on the inner side of the exhaust-gas muffler (1) in the region of the attachment device (6). A discharge channel (8), which leads to the outlet (5), is formed at least between a part region of the reinforcing sheet metal piece (7) and the adjoining region of the muffler housing (2).

Abstract: In a device for noise configuration in a motor vehicle which has an internal combustion engine with at least two gas conduits connected to different cylinders of the engine, the gas conduits are interconnected by means of a cross-flow section formed by a housing which encloses the gas conduits and which has at least two chambers in each of which one of the gas conduits is disposed, each of the gas conduits being in communication with the respective chamber by which it is enclosed by means of a respective cross-flow opening and the two chambers being in communication with one another by means of at least one cross-flow opening which is remote from the cross-flow openings of the gas conduits so as to provide for a phase shift of the sound waves of the gas flowing through the housing.

Abstract: A muffler system is provided for use with an auxiliary power unit. In one embodiment, and by way of example only, the system includes an outer can, an annular baffle, and a tube. The outer can has a sidewall including a forward end, an aft end, and a cavity extending therebetween. The sidewall is disposed about a first longitudinal axis, and the cavity has a first cross-sectional area and a smaller second cross-sectional area. The annular baffle is coupled to and extends radially inward from the outer can sidewall and has an opening that is disposed about a second longitudinal axis that is non-coincident with the first longitudinal axis. The tube extends through the annular baffle opening and is spaced apart from the annular baffle to define a radial gap therebetween, comprises acoustic material, and has a length and a substantially uniform cross-sectional area along the length.

Abstract: The shell main body for a muffler includes an inner shell in a cylindrical shape with a cross-section of an imperfect circle defined by small arc portions alternating with large arc portions; and an outer shell wrapping the inner shell and formed in a cylindrical shape similar to the inner shell. An end portion of the inner shell and an end portion of the outer shell are overlapped in a circumstantial direction of the shell main body to form a shell overlap portion that is capable of discharging vapor in a gap of the large arc portions formed between the inner shell and the outer shell into one of an outside and an inside of the shell main body. This shell overlapping portion is located in one of the small arc portions.

Abstract: Method and device for a particle filter for an exhaust system for a combustion engine, wherein the filter is regenerated by spontaneous combustion of particles accumulated in the filter. Exhaust gases from the combustion engine are led, during operation, past the filter when the counterpressure in the exhaust gases which is caused by the filter exceeds a certain level. The invention also relates to a silencer in a vehicle which is driven by the combustion engine.

Abstract: A catalytic converter-incorporated exhaust system is provided, which includes an exhaust tube through which exhaust gases emitted from an engine flow, and a muffler fluidly connected with a downstream end of the exhaust tube. This muffler includes a muffler casing having a plurality of expansion chambers defined therein, an exhaust introducing passage for introducing the exhaust gases from the exhaust tube into the expansion chambers in succession, two catalytic converters mounted in an downstream portion of the exhaust introducing passage and operable to substantially purify the exhaust gases, and an exhaust composition detecting sensor disposed outside the muffler casing in the exhaust introducing passage.

Abstract: The invention concerns an internal combustion engine exhaust line comprising an active noise reduction system with variable choke device, continuously regulated based on the instantaneous discharge rate pulses of exhaust gases exiting from the internal combustion engine, including an expansion chamber for closing phases of the variable choke device arranged upstream of said active noise reduction system and a cavity dispersing medium and high frequencies arranged downstream of the active noise reduction system. The expansion chamber for the closing phases of the variable choke device is integrated in a first depolluting system arranged upstream of said active noise reduction system.

Abstract: Disclosed herein is a muffler of a scroll compressor. The muffler includes a first muffler having a pair of chambers defined above an outlet of a fixed scroll to communicate with the outlet and a gas passage hole formed at the center of an upper end thereof, and a second muffler located around the first muffler to be spaced apart from the gas passage hole of the first muffler and having a chamber including one or more guidance paths of the fixed scroll. The muffler can achieve reduction of operational noise, sufficient separation of oil contained in discharge gas, and efficient isolation between a discharge pressure inside the muffler and outside suction pressure.

Abstract: By using a spun extrusion method to form a side entry exhaust inlet, a muffler can be completely stuffed and end caps can be spun onto opposing ends of the muffler on a high speed production line without interruptions. The side entry exhaust inlet is formed within a muffler shell at a position between the opposing ends. A spinning tool engages an internal peripheral area of the side entry exhaust inlet to form a spun extruded surface that extends outwardly from the muffler shell.

Abstract: A muffler having a muffler body divided into first and second exhaust chambers by a partitioning member which has a third exhaust chamber formed therein. An exhaust inlet introduces exhaust gas from an engine into the first exhaust chamber. First communication bores provide communication between the first and second exhaust chambers, and second communication bores provide communication between the second exhaust chamber and the third exhaust chamber. The third exhaust chamber is open to the atmosphere through an exhaust outlet pipe. An exhaust emission control catalyst is carried on an outer surface of the partitioning member facing the first and second exhaust chambers, as well as on an inner surface of the partitioning member facing the third exhaust chamber. An inner surface of the muffler body does not carry the exhaust emission control catalyst.

Abstract: An active exhaust muffler for an exhaust system of an internal combustion engine, having a housing through which a pipe system passes, the pipe system designed to be permeable for airborne sound in a first space, having an antisound generator which is arranged in a second space and antisound acting upon a third space through a wall opening during operation, the wall opening being provided in a partition that separates the second space from the third space, whereby airborne sound is transmitted from the first space to the third space through a sound outlet. To increase the lifetime of the antisound generator and thus the exhaust muffler, a labyrinth is provided in the third space, blocking a direct path between the sound outlet and the wall opening, and providing at least one indirect bypass for the propagation of airborne sound between the sound outlet and the wall opening.

Abstract: A cylindrical shell main body constituting a muffler main body is formed of two layers of an inner shell and an outer shell and has a cylindrical shape with a cross section that is not a perfect circle but is defined by alternated small arc portions and large arc portions similarly to an oval, or the like. The outer shell of the shell main body has, in each of their small arc portions, four radially projecting beads continuously extending in a circumferential direction along the small arc portions and being a predetermined distance apart from one another in an axial direction, thereby allowing an upper and lower gaps between the inner shell and the outer shell in the respective large arc portions of the shell main body to communicate with each other through passages formed by the beads.

Abstract: The present specification discloses a muffler for attenuating exhaust noise from an internal combustion engine. The muffler includes a main chamber, an intermediate pipe, a diffuser chamber, a spark arrester, and an exhaust pipe. Exhaust gases from the engine enter the main chamber after which they flow through the intermediate pipe. The intermediate pipe extends back through the main chamber to the diffuser chamber. The spark arrester is a screen held within the exhaust muffler and removably coupled to the exhaust pipe. Gases flow through the screen to separate hot particles. The exhaust pipe extends within the main chamber, completing a 180° bend within the chamber before exiting the main chamber and the muffler. An outer enclosure may surround the muffler. A method of attenuating exhaust gas noise is also disclosed.

Abstract: The exhaust sound and emission control systems comprise a series of embodiments of devices for reducing sound and noxious emissions from an automotive exhaust. The system may have an exhaust resonator having one or more catalytic converter elements in combination therewith in a single device. Alternatively, the system may have multiple angularly disposed chambers therein, with a series of swept baffles or guides in one of the chambers, thereby combining resonator and muffler functions in a single device. In another alternative, the system has a series of longitudinal tubes therein in combination with a series of V-shaped guides or vanes, combining catalytic converter, muffler, and resonator functions in a single device. The various elements of the different embodiments, e.g. catalytic converter element(s), double wall shell, perforated tubes and multiple flow paths, interconnecting crossover tubes, etc., may be combined with one another as practicable.