Abstract: A timbre-scaled exhaust assembly includes: an acoustic portion including an inlet collector including an entrance duct at a first end of the collector in fluid for receiving an exhaust flow from an internal combustion engine and exit ducts at a second end of the collector in fluid communication with a plurality of non-perforated tuning tubes; an outlet collector including entrance ducts in fluid communication with the plurality of non-perforated tuning tubes and an exit duct in fluid communication with an outlet of the exhaust assembly. The inlet collector splits the exhaust flow from the internal combustion engine into the plurality of tuning tubes such that a plurality of distinct exhaust flows pass through the plurality of tuning tubes and the outlet collector combines the exhaust flow. A combined exhaust flow exits the exhaust system through the exhaust tip.

Abstract: A saddle-riding type vehicle exhaust structure includes: an exhaust pipe that is connected to an exhaust port connecting to a combustion chamber of an engine and has a circular cross-sectional shape which is orthogonal to an exhaust flow direction; and a muffler that is connected to a downstream side in the exhaust flow direction of the exhaust pipe, wherein the exhaust pipe includes a muffler connection part that is connected to the muffler, an exhaust pipe upstream part that is connected to an upstream side in the exhaust flow direction of the muffler connection part, and an exhaust pipe downstream part that is connected to a downstream side in the exhaust flow direction of the muffler connection part, a cross-sectional area that is orthogonal to the exhaust flow direction of the muffler connection part is larger than each of a minimum value of a cross-sectional area that is orthogonal to an exhaust flow direction of the exhaust pipe upstream part and a minimum value of a cross-sectional area that is orthog

Abstract: A timbre scaled internal combustion exhaust system includes: an inlet collector including a single entrance duct at a first end of the collector in fluid communication with an exhaust flow from an internal combustion engine and an exit duct at a second end of the collector; a plurality of non-perforated parallel tuning tubes in fluid communication with the plurality of exit ducts of the inlet collector, the plurality of tuning tubes having lengths and diameters selected based on a desired note of the timbre scaled exhaust system; an outlet collector including a plurality of entrance ducts in fluid communication with the at least first and second tuning tubes and a single exit duct in fluid communication with an outlet of the exhaust system. The inlet collector splits the exhaust flow through the plurality of tuning tubes to create individual notes, and wherein the outlet collector combines the split exhaust flow to create a desired sound of internal combustion engine exhaust.

Abstract: A muffler may include a main body, a perforated tube assembly disposed within the main body, inlet and outlet end cap assemblies connected to opposite ends of the main body, and inlet and outlet expansion chambers defined in opposite ends of the main body by the perforated tube assembly, the inlet and outlet end cap assemblies, and portions of the main body. The perforated tube assembly may include a plurality of perforated tubes with tube supports connected to opposite ends of the perforated tubes. Portions of each perforated tube located between the tube supports may be individually wrapped with insulating material and collectively wrapped with an additional layer of insulating material. Unwrapped portions of each perforated tube may extend into the inlet and outlet expansion chambers defined in the main body.

Abstract: A motorcycle with a muffler disposed downwardly of a rider's seat positioned, in a side view, upwardly of a rear wheel when a rear shock absorber is extended, to minimize sideway bulging of the muffler from a vehicle body and improve ride comfort, while avoiding interference between the muffler and other parts. An outer shell of a muffler has a rhombus cross section. The muffler is disposed on at least one side in a vehicle width direction of a rear wheel wherein one pair of side walls extend in parallel with each other out of side walls of the outer shell extending in a vertical direction. A side cover is formed to extend along the upper and outer side walls of the four side walls of the outer shell to cover the muffler from a side, downwardly of a rider's seat.

Abstract: A silencer installed in a fuel cell system includes a plurality of expansion chambers connected to a predetermined apparatus of the fuel cell system, wherein the plurality of expansion chambers serially reduces acoustic noise of air discharged from the predetermined apparatus and a resonator connected to an expansion chamber of the plurality of expansion chambers, wherein the resonator reduces acoustic noise received from the expansion chamber in another frequency band, which is different from a frequency band of the acoustic noise reduced by the plurality of expansion chambers, where one of the plurality of expansion chambers comprises an inlet pipe which receives air from the predetermined apparatus, another of the plurality of expansion chambers comprises an outlet pipe which discharges air flowed into the plurality of expansion chambers, and an intermediate pipe is disposed between the plurality of expansion chambers.

Abstract: Method and apparatus for converting acoustic energy in an unshifted acoustic signal into an upshifted acoustic signal, and emitting the upshifted acoustic signal. Using a frequency converter, acoustic energy in a first frequency range in the unshifted acoustic signal is converted into acoustic energy in the upshifted acoustic signal in a second frequency range. The upshifted acoustic signal is emitted into an ambient acoustic environment. The second frequency range is higher than the first; the unshifted acoustic signal comprises an unwanted acoustic noise signal. The effect of the acoustic noise signal can be reduced by: enhanced attenuation of upshifted signal during atmospheric propagation; enhanced attenuation of upshifted signal by a non-gaseous attenuating medium; or decreased coupling of upshifted signal into resonances of a human body or mechanical structure.

Abstract: An apparatus for treating exhaust includes a housing having an inlet and an outlet, the housing defining a chamber. The inlet is in fluid communication with a source of exhaust. A mixing tube is connected to the inlet. The mixing tube has at least two branches and a plurality of apertures defined in a wall of the mixing tube. A substrate is disposed between the mixing tube and the outlet. The at least two branches converge at an end section of the mixing tube to form a mixing loop.

Abstract: An exhaust device of an engine includes an exhaust pipe connected to the engine, a silencer connected to the exhaust pipe and structured of an outer cylinder and an inner cylinder in which plural holes are formed, and a sound absorbing material disposed in a space formed between the inner cylinder and the outer cylinder. The exhaust device further includes a partition wall partitioning the space and supporting the sound absorbing material so that the sound absorbing material does not move in an axial direction of the silencer, and the partition wall includes a continuous hole allowing exhaust gas to flow through an upstream side to a downstream side of the partition wall in the space.

Abstract: An exhaust system for exhausting multiple cylinders of a small engine, wherein the exhaust system includes a plurality of exhaust units is described herein. Each exhaust unit of the exhaust system is operatively and fluidly connected to a separate cylinder of the small engine such that the exhaust gases from each cylinder remain separated as they pass through different exhaust units of the exhaust system. The exhaust system includes at least two exhaust units, and of the exhaust units is separated by an inner chamber wall that is shared by adjacent exhaust units yet prevents fluid communication between the adjacent exhaust units.

Abstract: An exhaust muffler comprising an inlet in fluid communication with an outlet via an expansion chamber (16), the expansion chamber (16) comprising an inner core (22) extending in the longitudinal direction, wherein the muffler is provided with at least one accelerator (24a) tube between the inlet and the expansion chamber. The disclosure extends to a catalytic converter of a similar construction.

Abstract: A muffler comprising an inner pipe having one end connected to an upstream side of an exhaust pipe of an engine exhaust system, and another end connected to a downstream side of the exhaust pipe, an outer pipe covering at least part of the inner pipe, a hole being formed in a pipe wall of the inner pipe, a resonance chamber formed in a space between the inner pipe and the outer pipe, and a connection passage formed on an outer peripheral surface of the inner pipe along an axial direction of the inner pipe. The connection passage comprising a plurality of sections connected in series to form the connection passage as a single continuous passage.

Abstract: One or more methods for recovering waste heat from a combustion system performing a first operation and a second operation with the waste heat are provided herein. The method can include providing exhaust from a combustion system performing the first operation to an inner housing of a heat recovery silencer. Heat can be transferred from the exhaust to a heat transfer fluid in a heat recovery flow path to form a heated heat transfer fluid. The heat recovery flow path can be formed between the inner housing and an outer housing of the heat recovery silencer to form a heated heat transfer fluid.

Abstract: A silencer for an exhaust system of a combustion engine, more preferably of a motor vehicle, has two end face bottoms facing away from each other, a closed circumferential jacket, at least one silencer insert, at least one inlet pipe and at least one outlet pipe. At least one of the pipes extends through the jacket into the silencer interior and is fastened to the jacket. The manufacture can be simplified if the pipe extending through the jacket has a cone, if the silencer insert on an intermediate pipe has a mating cone which engages in the cone.

Abstract: A silencer cover adapts to a heat expansion of a silencer even when, for example, the silencer cover has a large size and is attached to the silencer over an area from the front to the rear. A silencer cover is provided for a silencer connected to a downstream end of an exhaust pipe of an engine. The silencer cover is fixed to a fixing support provided to the silencer. The silencer is heat-expanded with the fixing support part fixed as a base. The fixing support part is provided at a front end portion, in a vehicle front-rear direction, of the silencer. With a tail pipe constituting a rear end portion of the silencer, the rear end portion of the silencer is provided with a slide structure in which the silencer cover is slidably supported.

Abstract: A resonator for a dual-flow exhaust system of an engine is provided. The resonator includes a housing defining an enclosure and a baffle spanning the housing and separating a first and second expansion chamber of the enclosure, the baffle including at least one opening. The resonator further includes a first and a second exhaust conduit extending through the baffle and housing, each conduit in fluidic communication with a separate cylinder bank and including a perforated portion fluidly coupled to the enclosure, each perforated portion positioned in separate expansion chambers.

Abstract: This silencer (10) for a motor vehicle exhaust line of the type comprising: a casing (12) internally delimiting an exhaust volume; an exhaust gas inlet (16) opening into the exhaust volume; and an exhaust gas outlet pipe (18) communicating with the exhaust volume and having an outlet orifice (30) to the outside of the silencer (10), is characterized in that the outlet pipe (18) comprises a section (32) pressed against the casing (12), the casing (12) having at least one perforation placing the pressed section (32) in communication with the exhaust volume.

Abstract: A vehicle, such as a motorcycle, can include an engine, an exhaust pipe, and a silencer. The silencer can include a main body and first and second pipes. An upstream end of the first pipe can be connected to the exhaust pipe, and be provided in the main body. The second pipe can be provided apart from the first pipe on the downstream side of the first pipe, coaxially with the first pipe, and extending through a downstream lid of an outer tube of the main body. The downstream portion of the first pipe can have an inner diameter that gradually decreases from the upstream side toward the downstream end. The upstream end of the second pipe can be provided in the main body and have a larger inner diameter than the inner diameter of the downstream end of the first pipe.

Abstract: An exhauster for a motorcycle with a reduced number of components and reduced cost in a structure containing a variable passage area valve. An exhaust chamber has a box-shaped chamber main body, a plurality of expansion chambers a through c formed by sectioning the interior of the chamber main body with partitioning walls, and communication passages for connecting the expansion chambers a through c with one another. A variable passage area valve that controls passage area is contained in the communication passage.

Abstract: One or more systems for silencing and extracting waste heat from exhaust of a combustion system for performing an operation and using the waste heat to perform an additional operation are provided herein. The system can include a heat recovery silencer. An inner housing of the heat recovery silencer can be in fluid communication with a combustion system. A heat recovery flow path of the heat recovery silencer can have an outlet port in fluid communication with an auxiliary device inlet, and the heat recovery flow path can have an inlet in fluid communication with an axially device outlet of the auxiliary device.

Abstract: A vehicle muffler, which is structured in a coiled fashion, has a tube extending through the circumferential wall. This tube is welded to the circumferential wall and fastened by mechanical deformation to a support wall of an inner insert piece.

Abstract: An exhaust-pipe structure for a saddle-ride type vehicle includes expansion paths each having a capacity appropriate for the output capacity of a corresponding cylinder. A front exhaust pipe and a rear exhaust pipe extend from a front cylinder and a rear cylinder constituting a V-type engine, respectively. A silencer is connected to rear end portions of the front and rear exhaust pipes. As expansion chambers, the silencer is provided with a lower first chamber led from the front cylinder and an upper first chamber led from the rear cylinder. A protruding space protruding from the lower first chamber is formed so that the capacity of the lower first chamber led from the front cylinder is larger than the capacity of the upper first chamber led from the rear cylinder.

Abstract: A vehicle exhaust component includes an outer shell defining an internal cavity, at least one baffle located within the internal cavity, and at least one tube supported by the baffle. The baffle is fixed to the outer shell and includes at least one opening. The tube has first and second tube ends with one of the first and second tube ends being supported within the opening in the baffle. At least one slot is formed within the one of the first and second tube ends at the at least one opening. The slot facilitates noise reduction during cool down of the vehicle exhaust component.

Abstract: An exhaust device for a straddle type vehicle allowing a compact design while still satisfying the sound deadening characteristic requirements is provided. The exhaust device for a straddle type vehicle comprising: an exhaust pipe that is connected to an engine; a silencer that is connected to the exhaust pipe wherein the exhaust pipe is provided with a Helmholtz resonator, and the Helmholtz resonator is filled with a sound absorbing material. The Helmholtz resonator is formed with an opening that communicates with the inside of the exhaust pipe. The opening is formed in a place where the sound pressure in the exhaust pipe is high during the operation of the engine.

Abstract: This Invention relates to a kind of devices with no emission resulted for treatment of exhaust gas. The Device comprises a vessel having openings that serve only as inlet. At least two exchange sections are provided inside the vessel after inlet of exhaust gas. There is a gas chamber at each connection part between two sequential sections. The gas exchange chamber at the first gas exchange section has a through opening leading to outside atmosphere area, and at each one from the second to the last exchange section, there is a feedback pipe to connect to the inlet of the first stage of exchange section. With this configuration, on entering into the exchange section, exhaust gas will be ejected inwards and causes very strong entrainment, which makes the gas chamber become vacuum and sucks air with oxygen from atmosphere into gas chamber via the through opening to atmosphere.

Abstract: A system for reducing an acoustic load of a fluid flow includes a first pipe. The first pipe includes a first end and a second end and a first aperture and a second aperture, the first and second apertures being intermediate the first and second ends. A second pipe includes a first end and a second end and a third aperture intermediate the first and second ends. The second pipe is connected at its first end to the first pipe at the first aperture. A bypass pipe includes a first end connected to the second aperture of the first pipe and a second end connected to the third aperture of the second pipe. A method of reducing an acoustic load of a flow in a standpipe connected to a first pipe configured to carry a main flow includes providing a bypass flow from the first pipe to the standpipe.

Abstract: Disclosed is an exhaust system (100) for an internal combustion engine, comprising a first exhaust train that is provided with a penetrable first muffler (120), especially a rear muffler, and at least one second exhaust train which encompasses a second penetrable muffler (122), particularly a rear muffler. The structure of the first muffler (120) differs from that of the second muffler (122).

Abstract: A muffling chamber is located between a first main body wall and a second main body wall with respect to a height direction. An outflow pipe includes: a first opening that connects an outflow passage with a muffling chamber in the vicinity of a first main body wall; and a second opening that connects the outflow passage with the muffling chamber in the vicinity of a second main body wall. The liquid staying on the first main body wall of a first muffler flows into the outflow passage through the first opening. The liquid staying on a second main body wall of a second muffler flows into the outflow passage through a second opening. Therefore, the symmetry of the first muffler and the second muffler is compatible with anti-corrosion.

Abstract: Snap action valve assemblies for use in conduits of automotive exhaust systems have their operation controlled by use of inertia damper elements coupled to an axle of a rotatable valve plate of the valve assembly.

Abstract: A customizable integrated modular exhaust system is provided having a hollow shell muffler body formed from two symmetrical stamp formed shell members that sealably attach to a tailpipe that transverses the hollow shell, and extends through each end of the hollow shell. Exhaust gases are delivered to the muffler body from an engine, by at least one inlet tube communicably attached to the muffler body and connected to the engine via a flange. The muffler body may have various internal configurations, including a disc baffle or catalytic converter configuration.

Abstract: An exhaust muffler (1) is provided for an at least partly dual-flow exhaust system of an internal combustion engine, especially of a motor vehicle. The exhaust muffler has a housing (2), which encloses an interior space (3), with two exhaust pipes (6), through which exhaust gas can flow in parallel, and which are each led through the interior space (3), and which have a side opening (8) each within the housing (2). A neck body (9) connects the two side openings (8) of the exhaust pipes (6) in a communicating manner to form a Helmholtz resonator with the interior space (3) of the housing (2), which interior space (3) acts as a resonance volume (12).

Abstract: This invention relates to a kind of devices with trace emission resulted for treatment of exhaust gas. The device comprises a vessel having only one opening that serves as inlet. At least two gas exchange sections in sequence are provided inside the vessel after inlet of exhaust gas, between two gas exchange sections there is a gas mixture chamber at their connection part. The gas exchange chamber at first gas exchange section has a through opening leading to outside atmosphere area. With this configuration, on entering into the gas exchange section, exhaust gas will be ejected inwards and causes very strong entrainment, which makes the gas chamber become vacuum and sucks air with oxygen from atmosphere into gas chamber via the through opening to atmosphere. Formed high-pressure gas is burned furiously with combustible gas in the gas chamber at next stage, and the remaining exhaust gas is transferred into next gas exchange section with very high-speed revolution occurring on exhaust gas and momentum transfer.

Abstract: A vehicle (1) is provided with an exhaust pipe (2) extending from an engine mounted in the front part of the vehicle to a branch part (24) in the rear part of the vehicle, and right and left branch pipes (25, 26) extending from the branch part to mufflers (5, 6) on both right and left sides. The branch part (24) is arranged so as to be offset to the side of either one muffler (5) of the right and left mufflers with respect to the center in the vehicle width direction; the exhaust pipe has an upstream part (2, 21) laid linearly to a bend part (22) positioned in the center in the vehicle width direction near the rear end of a fuel tank, and an oblique part (23) laid slantwise from the bend part toward the branch part; and the length of the branch pipe (25) having a longer distance to the muffler is approximately equal to the length of the oblique part (23).

Abstract: A muffler for a vehicle, such as a scooter type motorcycle, comprises an inner tubular member and an outer tubular member. An inner surface of the outer tubular member faces an outer surface of the inner tubular member. A ring shaped or annular member is positioned between the outer surface of the inner tubular member and the inner surface of the outer tubular member. The annular member has a substantially hollow cross section and is elastically deformable in a direction perpendicular to a longitudinal axis of the inner tubular member and the outer tubular member.

Abstract: A variable muffler corresponds to a muffler of an internal combustion engine including a variable valve that controls the flow of exhaust gas. The variable muffler includes a muffler body forming a muffler chamber, an inlet pipe with an opening at the muffler chamber to direct the flow of exhaust gas from the opening towards the muffler chamber, and a muffler-in pipe arranged in the muffler chamber. The muffler-in pipe includes an opening facing the opening at the muffler chamber, and into which the exhaust gas output from the opening flows in a predetermined direction. The muffler-in pipe further includes a slope inclining vertically downwards towards the opening, and extending in a direction different from the predetermined direction. By such a configuration, a muffler of an internal combustion engine having proper driving of the valve ensured can be provided.

Abstract: Resonator arrangement in an acoustic muffler for a refrigeration compressor having a shell (1), inside which is mounted an acoustic muffler comprising a hollow body (10) defining at least one dampening chamber (13), which carries a gas inlet duct (20) and a gas outlet duct (30), each presenting a respective length and having a respective wall thickness, at least one of the gas inlet and gas outlet ducts (20, 30) carrying, extending along at least part of its length, a respective plurality of tube type resonant ducts (40), each resonant duct (40) presenting a first end (41), open to the interior of the respective gas duct (20, 30) and a second end (42), opposed to and spaced from the first end (41), each said resonant duct (40) being dimensioned to present a determined length and a determined diameter, which are calculated to define a certain reactive impedance and a certain dissipative impedance for the acoustic muffler, in a determined frequency band.

Abstract: A flow-through muffler includes a plurality of heat conducting walls, baffles, or partitions that together define a plurality of passages arranged to form acoustic waveguides, attenuators, and/or cancellation chambers, the walls, baffles, or partitions increasing a surface area exposed to the exhaust gases to facilitate extraction of heat while attenuating or canceling the resulting sound pressure waves. The muffler may have a cooling arrangement mounted thereon, and thermoelectric generator elements or other heat-powered device, such as a reformer, connected across the heat differential between the cooling arrangement and an exterior surface of the muffler housing that is in thermal contact with the heat conducting walls, bafflers, or partitions. In addition, the muffler may be made tuneable by providing a device for varying a length of one of the passages relative to another passage, and by including a sound cancellation chamber at an intersection of the passages.

Abstract: The muffler comprises a tubular shell which is internally lined with a noise-deadening material and is closed at its ends by a front wall provided with an inlet connectable to receive exhaust gas, and by a rear wall. A first chamber and a second chamber, which are separated by a transverse wall having an inlet opening and an outlet opening, are defined within the tubular shell. A perforated inlet pipe extends within first chamber from the inlet to the inlet opening. Gas-piping elements extend within the first chamber and have one end open to the outlet opening, and another end connectable to the exhaust pipes. The inlet opening and the outlet opening are substantially equal in diameter to the inlet pipe, and are interconnected via a toroidal duct that is arranged within the second chamber and is substantially equal in diameter to the inlet pipe.

Abstract: A system for reducing an acoustic load of a fluid flow includes a first pipe. The first pipe includes a first end and a second end and a first aperture and a second aperture, the first and second apertures being intermediate the first and second ends. A second pipe includes a first end and a second end and a third aperture intermediate the first and second ends. The second pipe is connected at its first end to the first pipe at the first aperture. A bypass pipe includes a first end connected to the second aperture of the first pipe and a second end connected to the third aperture of the second pipe. A method of reducing an acoustic load of a flow in a standpipe connected to a first pipe configured to carry a main flow includes providing a bypass flow from the first pipe to the standpipe.

Abstract: A switchable exhaust system apparatus. The switchable exhaust system apparatus is switchable between a quiet or normal mode and a loud mode when desired.

Abstract: A vehicle exhaust assembly for improved evacuation of exhaust gases from an internal combustion engine. The system comprises a modular replacement exhaust system having a novel header pipe and muffler. The present invention readily adapts to a range of vehicle applications including automobiles, motorcycles, and all terrain vehicles.

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 engine muffling system includes a Helmholtz tuning chamber to meet the changing acoustic muffling requirements associated with multiple applications. The engine muffling system in one embodiment includes at least one chamber configured as a plenum device, typically filled with an aggregate material or acoustic absorbing particulate material(s) in order to produce a tortuous path through the at least one chamber.

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: An exhaust system for an engine that reduces muffler weight, assures a silencing effect and prevents a leak of exhaust gas. A muffler has an inner cylinder disposed in an outer cylinder, and is separated into a plurality of expansion chambers. A communicative passage for communicatively connecting the expansion chambers together is formed between the outer and inner cylinders. Edge parts of the communicative passage contact the outer cylinder and are welded thereto.

Abstract: An exhaust system for an internal combustion engine having two banks of cylinders by which pulses of exhaust gas are alternately directed to a diverter subassembly. The diverter subassembly, which is located in the muffler, includes a perforated gas decelerator chamber which divides each pulse of exhaust gas between two exhaust outlets and causes a low pressure wave to occur in the exhaust system to enhance scavenging of a subsequent pulse of exhaust gas and thereby improve engine performance and mileage. The muffler further includes one or more cores and may or may not include a dead air space chamber to provide attenuation and tonal balance to the exiting exhaust gas.

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 noise control apparatus for a motorcycle exhaust system. The apparatus includes at least one exhaust pipe assembly having a direct pass-through mode and an indirect mode wherein exhaust gases are optionally directed through noise attenuating means. The apparatus includes at least one valve for controlling exhaust gas flow, a motor, a switch controlling said motor, a wire carrier, a wire connected between the carrier and the valve(s), and a rotary threaded drive shaft driven by the motor for moving the positioner. The threaded drive shaft includes radially extending and circumferentially facing stop means on both sides of said wire carrier. The valve is positioned under the control of the switch.

Abstract: An interference-based exhaust noise attenuation device and method for exhaust flow from an internal combustion engine that generates compressive waves in the exhaust flow. The device includes at least a direct path for the exhaust flow; a looped path for the exhaust flow, with volumes of the direct path and the looped path differing by an amount that results in a staggered rearrangement of the compressive waves in the paths; a splitter that splits the exhaust flow into the direct path and the looped path; and a merger that merges the exhaust flow from the direct path and the looped path. When the exhaust flow from the direct path and the looped path are merged, at least some noise cancellation occurs. In other embodiments, plural direct paths, looped paths, splitters, and/or mergers can be used in various combinations.

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.