Abstract: The invention provides a muffler assembly (10) for exhaust gas flow communication with an engine exhaust. The assembly (10) includes a muffler (12) having inlet and outlet ports (14, 16). The assembly (10) also includes first and second flow of passages in common fluid communication with the outlet port (16) and in variable fluid communication with the inlet port (14). The first and second flow passages meet at first and second connecting points. The first connecting point is located in the proximity of the inlet port (14). The first flow passage has a higher resistance to fluid flow than the second flow passage. The assembly (10) also includes a valve means (24) generally located past the first connecting point inside the second flow passage for selectively proportionating exhaust gases passing through the passages. The first flow passage includes three or more conduits (26, 28, 30) being in fluid communication with each other.

Abstract: A firearm suppressor includes an outer housing and a baffle stack mounted inside the outer housing. The baffle stack includes baffles and spacers. The baffles and spacers are configured to allow a projectile to pass through while causing exhausted gas to flow through various chambers and channels in different directions.

Abstract: A muffler for a vehicle includes an inner casing, the inner space of the inner casing is divided by baffles to form a plurality of chambers, the inner casing having an entrance defined in one end and an exit defined in the other end, the entrance and the exit communicating with each other. An insulator surrounds the contour of the inner casing. An outer casing surrounds the contour of the insulator, the outer casing being made of synthetic resin.

Abstract: An acoustic baffle device for sealing a cavity of a vehicle body at a predetermined cross section of the cavity is provided. The device has a carrier having an opening therein, a heat expandable sealing material affixed to the carrier, and a flap assembly having a flap normally held in place by a spring so as to close off the opening, wherein the flap is capable of being deflected by insertion of a tube through the opening.

Abstract: An aftertreatment module for use with an engine is disclosed. The aftertreatment module may have a first chamber with an inlet, and at least one catalyst substrate disposed in the first chamber in a flow path through the inlet and having a flow direction from an inlet face to an outlet face in general alignment with the flow path. The aftertreatment module may also have a second chamber with at least one outlet in general alignment with the flow direction through the inlet. The aftertreatment module may further have at least one noise attenuation passage fluidly connecting the first chamber with the second chamber. The at least one noise attenuation passage may be oriented generally orthogonal to the inlet and the at least one outlet and be located between the inlet and the outlet face of the at least one catalyst substrate.

Abstract: A tunable muffler for a vehicle may include a center frame having a first cavity, a detachable connected base plate being detachably connected to the center frame and a tunable baffle to tune the muffler. The center frame may include a second cavity, and the tunable baffle may be mounted substantially 90° to the plane of the base plate. The baffle may be mounted substantially parallel to the plane of the base plate, and the baffle may be controlled by a control device.

Abstract: A resonator is disclosed which includes: a sleeve insert and an outer duct sealingly coupled to the sleeve insert. The sleeve insert has a wall with a first aperture in the wall at a first axial distance, a second aperture in the wall at a second axial distance, and a rib extending radially outwardly with the rib located between the first and second apertures. The outer duct sealingly couples to the sleeve insert proximate first and second ends of the inner sleeve and at the rib. The sleeve insert and the outer duct are formed of plastic materials which are coupled by welding or via o-rings placed on the sleeve insert. Cavities, in the vicinity of the apertures, are formed in the outer duct. The cavities, which are fluidly coupled to the sleeve insert via the apertures, attenuate noise.

Abstract: A sound absorber comprises an elongated gas channel, through which a flowing gas passes in operation of the sound absorber; and at least one helical fixture mounted in a longitudinal section of the gas channel. The helical fixture defines a helical gas passage through the longitudinal section of the gas channel. Further, the helical fixture defines at least one longitudinal Helmholtz resonator within the gas channel which is excited by sound waves propagating in the flowing gas passing through the at least one gas channel.

Abstract: A muffler (1) for an exhaust system (2) of an internal combustion engine, especially of a motor vehicle, with a muffler housing (3), which encloses a housing interior space (5), and with at least one exhaust gas-carrying hollow body (4) with two half shells in a half shell construction. The hollow body is arranged in the housing interior space (5). The two half shells (14, 15) of the hollow body (4) are fastened to one another in the area of a separating plane (16). The assembly of the muffler (1) or of the hollow body (4) can be simplified if the two half shells (14, 15) are fastened to one another by fastening elements (17, 18), which are formed directly on the half shells (14, 15).

Abstract: In one embodiment, an exhaust device has an inner cone stack assembly made up of connectedly overlapping inner cone components with frustums. The inner cone stack assembly is disposed within an outer shell and connected to the exhaust device using contoured flanges to match the contours of mounting surfaces on the exhaust device. An outer cone stack assembly made up of baffle ring retainers having a number of detents and baffle frustums with ears inserted in the detents. The outer cone stack assembly is also disposed within the outer shell. The cone frustums of the inner cone stack assembly and the baffle frustums of the outer cone stack assembly cooperate to break down particles and attenuate sound.

Abstract: A motor chain saw has a motor housing with a drive unit for driving a saw chain on a guide bar. The drive unit is an internal combustion engine with a cylinder and a crankshaft extending transversely to a longitudinal axis of the motor chain saw. A drive pinion is mounted on a first end of the crankshaft. A cooling air blower with a blower wheel is mounted on the second end of the crankshaft. A cooling air stream of the blower flows transversely to the longitudinal axis of the motor chain saw about the cylinder and exits through a housing opening. A hand guard arranged between a handle and a front end of the guide bar is connected with one leg near the housing opening for the cooling air stream. In front of the housing opening a baffle element is supported on the leg of the hand guard.

Abstract: An exhaust silencer assembly includes an exhaust duct and an exhaust silencer. The exhaust silencer is disposed about the exhaust duct and has a plurality of solid baffles and at least one perforated baffle The exhaust silencer assembly is disposed downstream of an auxiliary power unit and at least partially attenuates the downstream noise of the combustion gases that result from operation of the auxiliary power unit. In one embodiment, at least one of the plurality of solid baffles is disposed to extend axially between generally radially extending solid baffles, perforated baffle(s), or partially perforated baffles. The axially extending solid baffle allows for cavity depth variation in the silencer to optimize tuning of particular frequencies from the auxiliary power unit.

Abstract: A container data center includes a movable container, two server systems having a cold aisle and two hot aisles, two fan apparatuses, an exchanger, and an air intake apparatus. The air intake apparatus includes a number of air intake elements each defining an air channel. The fan apparatuses are operable to transfer hot airflow in the hot aisles into the heat exchanger, and then the heat exchanger transforms the hot airflow into cold airflow and transfers the cold airflow into the cold aisle through the air intake apparatus. The air intake elements are connected together and cover the cold aisle. The air intake elements of the air intake apparatus are arranged in a “V” shape along an orientation toward the airflow of the cold aisle.

Abstract: The present invention discloses a suction muffler for a hermetic compressor which reduces noise of refrigerant. A plate film operating as a kind of flow resistance is provided on a refrigerant suction passage in various shapes and specific positions. Therefore, the suction muffler can effectively reduce pressure pulsation transferred to the outside and guarantee flow efficiency, although the refrigerant is directly sucked thereinto.

Abstract: A silencer for a firearm which incorporates a cylindrical housing, front end cap, mean of attachment to the muzzle of a firearm, spacers and an improved cone baffle design. The proposed device incorporates a novel cone baffle design which uses concave flutes to increase surface area and thereby sound reduction. The geometry of this new cone baffle minimizes the weight of a silencer, maximizes internal volume, and effectively reduces sound and flash which are the result of a discharging firearm.

Abstract: A muffler for a vehicle includes a plurality of baffles fixed at a predetermined distance in a longitudinal direction of a muffler housing, an exhaust gas inflow pipe, an intermediate pipe, and a plurality of exhaust gas outflow pipes having an inlet thereof positioned in the same chamber defined by the adjacent pair of the baffles with the outlet of the intermediate pipe to considerably reduce exhaust noise, flow-induced noise, and booming noise of exhaust gas. The muffler is effectively protected from thermal damage of a vehicle by implementing a sound-absorbing heat-insulating material therein, and impresses consumers with dynamic, powerful, and polished image by making the exhaust gas outflow pipe in a dual type composed of first and second exhaust gas outflow pipes and disposing the outlet at the lower center of a rear bumper to be exposed to the outside, thereby considerably improving productivity of vehicles.

Abstract: An exhaust component is provided including an inlet portion for accepting an exhaust stream entering therein from an exhaust system, two or more separator components fixed to the inlet portion for separating the exhaust stream into two or more streams at the point of egress from the inlet portion, two or more chambers fixed to the separator components, the chambers for muffling sound of the exhaust stream, two or more collector components fixed to the chambers opposite the separator components for collecting the separated exhaust streams upon egress from the chambers, and one or more outlet portions fixed to the collector components at the end opposite the chambers for carrying separated or merged exhaust streams out of the exhaust component.

Abstract: A baffle arrangement for a genset enclosure is disclosed. The genset enclosure may include an opening in a side of the enclosure and a plurality of baffles internally supported in the enclosure between the opening and a radiator portion. The baffles may be positioned in a sound path to reflect a sound transmitted along the sound path. A method for reducing sound in a genset enclosure is also disclosed. The method may include arranging a plurality of baffles within the enclosure between an opening and a radiator portion, the baffles being positioned in a sound path to reflect a sound transmitted along the sound path.

Abstract: A Tier 4 ready silencer that can accept both DOCs and DPFs to meet Tier 3 and can interface with an SCR system to meet Tier 4. The invention includes a silencer compartment with empty filter/catalyst banks in the shape of a V. DOCs and DPFs can be added and arranged in the V-shaped banks as needed. Various exhaust fins direct exhaust flow through the filters/catalysts. Multiple exhaust inlets to the device provide the most direct route possible from the engine outlets. A mixing tube and an SCR system can be added to the output port to comply with Tier 4.

Abstract: A muffler for attenuating acoustic noise in a gas flow which includes a casing having an inlet and an outlet, such that the gas flow passes through the casing from the inlet to the outlet. The muffler also includes an acoustic trap disposed within the casing and which spans the distance between opposing top and bottom walls of the casing. The acoustic trap further comprises a first arcuate deflector having a concave frontside surface configured to direct the gas flow from the inlet through a first segment of an expanding spiral revolution, and one or more second arcuate deflectors which are radially offset from the first arcuate deflector and configured to direct a portion of the inlet gas flow through a remainder segment of the expanding spiral revolution.

Abstract: A muffler for attenuating acoustic noise in a gas flow that includes a casing having a substantially-rectangular cross-section with an inlet opening in an inlet end and an outlet opening in an outlet end, so that a gas flow containing acoustic noise passes from the inlet opening to the outlet opening. The muffler also includes a V-shaped sound diffuser disposed within the casing and spanning the distance between opposing top and bottom walls of the casing. The sound diffuser comprises a pair of elongate leg plates having base ends attached to the outlet end on opposite sides of the outlet opening, and tip ends merged into an apex that is aligned with the inlet opening. Each leg plate has a plurality of apertures formed therein, and the apex splits the inlet gas flow into two side flows, with each side flow passing through the plurality of apertures in one of the leg plates to reach the outlet opening.

Abstract: A heat expandable baffle for sealing automotive cavities comprising a carrier plate with an outer perimeter and a strand of a heat expandable material along the major part of the outer perimeter, this strand circumscribing a central section of the carrier plate which is not covered by the heat expandable material, the outer perimeter defining a mean plane limited by the outer perimeter, the central section of the carrier plate being bent away from the mean plane in a way that the point on the central section which has the greatest distance from the mean plane lies at a distance from the mean plane which is at least 5% of the maximum linear length of the carrier plate, and/or the central section having a lumped mass distribution.

Abstract: An exhaust device of an internal combustion engine for reducing exhaust sound and for suppressing the occurrence of a torque valley. A sound-deadening and pressure-dissipating device connected to the downstream end of an exhaust pipe includes a spherical member having an opening portion opening toward a downstream edge of the exhaust pipe. Exhaust gas from the exhaust pipe is reflected by an inner spherical surface of the spherical member to reduce exhaust pressure in the spherical member and then is discharged from the opening portion.

Abstract: A silencer, particularly rear silencer, for an exhaust system of a combustion engine, particularly of a motor vehicle, has a housing in which an outlet chamber is located. An outlet pipe arrangement leads out of the housing which on the inlet side is fluidically connected to the outlet chamber. A particularly compact design can be realized if the outlet pipe arrangement is configured as pipe-in-pipe arrangement including at least one deflection pipe closed on one side and arranged in the housing and an outlet pipe led out of the housing.

Abstract: A motor vehicle exhaust line silencer includes: an upper shell (2) having a substantially flat upper end wall (16); and a lower shell (4) having a substantially flat lower end wall (24) parallel to the upper end wall (16), the upper and lower shells (2, 4) delimiting between them an internal volume (6) of the silencer (1). The silencer (1) includes at least an internal partition wall (12) substantially parallel to the upper (16) and lower (24) end walls and arranged in the internal volume (6), the upper (16) and lower (24) end walls having respective reliefs (48, 50, 52) projecting into the internal volume (6) and cooperating to immobilize the internal partition wall (12).

Abstract: Embodiments of the present invention provide an improved baffle for use in a muffler exhaust system and a system utilizing such baffle. The improved baffle comprises a first conduit portion having a first diameter, a second conduit portion having a second diameter, wherein the second diameter is greater than the first diameter, and a diameter step-up conduit connection portion having two ends, one that connects to the first conduit portion and the other that connects to the second conduit portion. The integrated baffle is disposed within the muffler of an exhaust system such that exhaust from an internal combustion engine enters the first conduit portion first, travels through the first conduit portion and then through the second conduit portion, and is then released into the air.

Abstract: Methods, systems, and apparatuses for exhaust silencers for engines, such as microturbines, are described. An exhaust silencer reduces noise produced by an engine. While passing through an exhaust silencer, an exhaust stream from the engine makes one or more turns, thereby reducing turbine noise. An exhaust silencer includes a body, a cavity in the body, a baffle plate that partially divides the central cavity, an inlet port formed in a first surface of the body, and an outlet port formed in a second surface of the body. The inlet port is configured to receive an exhaust stream that flows through the cavity, around the baffle plate. The outlet port is configured to discharge the exhaust stream from the body.

Abstract: A fuel tank assembly includes a baffle plate mounted under the upper part of the fuel tank to form a predetermined distance between the baffle plate and the fuel tank bottom. The fuel tank assembly includes a fuel tank, a baffle plate having an upper plate in which a penetration hole is formed and a side wall integrally formed at an edge of the upper plate. A bracket mounts the fuel tank and the baffle plate, wherein, the upper plate and the side wall of the baffle plate are mounted to the fuel tank and have a predetermined distance therebetween.

Abstract: A fairing is configured for use with the exhaust stack of a heavy-duty vehicle. The exhaust stack has an exhaust pipe with an intake end for receiving exhaust gases from an internal combustion engine and a discharge end for discharging the exhaust gases. The fairing includes a streamlined exterior surface and a cavity for receiving the discharge end of the exhaust pipe. An aperture extends through a rear portion of the exterior surface so that exhaust gases discharged from the discharge end of the exhaust pipe pass through the cavity and out of the aperture. The fairing further includes a coupler to couple the fairing to the exhaust pipe.

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 noise and vibration reduction system for an engine affixed to a body and a method for reducing vibrations in the body produced by that engine during operation. The present invention is particularly related to noise and vibration reduction in auxiliary power units installed on long-haul trucks and similar types of transportation vehicles. The primary noise and vibration reduction components of the present invention include an air intake silencer, a vibration tuner, and an engine speed limiter.

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 muffler apparatus for a vehicle, may include a muffler housing; baffle plates that are disposed in the muffler housing and divides an internal space of the muffler housing; an intake pipe that is supported by at least one of the baffle plates and takes in exhaust gas; and an exhaust pipe that is supported by at least one of the baffle plates and takes in the exhaust gas discharged from the intake pipe and discharges the exhaust gas outside the muffler housing, and of which a pipe line of the exhaust pipe circulates through the internal space of the muffler housing.

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 vehicle exhaust component provides comparable fully packed noise reduction capability without requiring a fully packed configuration. A pack is mounted within an internal cavity defined by an exhaust component body. A plurality of pack positions are defined within the internal cavity and at least one pack is positioned at a desired pack position to provide a desired noise reduction.

Abstract: A heat expandable baffle for sealing automotive cavities comprising a carrier plate with an outer perimeter and a strand of a heat expandable material along the major part of the outer perimeter, this strand circumscribing a central section of the carrier plate which is not covered by the heat expandable material, the outer perimeter defining a mean plane limited by the outer perimeter, the central section of the carrier plate being bent away from the mean plane in a way that the point on the central section which has the greatest distance from the mean plane lies at a distance from the mean plane which is at least 5% of the maximum linear length of the carrier plate, and/or the central section having a lumped mass distribution.

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: An air distributor is provided that includes, but is not limited to a perforated body, insertable at a joint between a first air duct, which extends in one direction, and a second air duct, that extends in a second different direction, to redirect air flowing in the first air duct into the second air duct and to reduce low frequency high volume noise.

Abstract: The present invention is for a triangular cross section symmetrical engine exhaust muffler for an internal combustion engine. Its internal design provides baffles symmetrically disposed about a plane centrally located equidistant from the ends of a tube having a triangular cross section. The design has three baffles spaced to minimize backpressure but angled to enhance acoustic reflections within the chamber formed by the tube having a triangular cross section, baffles, and the affixed endplates including the inlet/exhaust ports. These acoustic reflections serve to modify the sound emanating from the exhaust manifold or manifolds of the internal combustion engine. The muffler chamber also serves to smooth out the pulsating gas flow emanating from the engine as a result of the combustion cycle.

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: A muffler includes a muffler body in which a muffler chamber is formed by a base, a cover, and a baffle accommodated in the muffler chamber and disposed in the vicinity of the exhaust gas entry port of the muffler body. A guide portion which changes flow of an exhaust gas that enters from the exhaust gas entry port is integrally provided to the baffle by cut-and-raise of a portion of the baffle.

Abstract: A muffling chamber (5) is located between a first main body wall (42A) and a second main body wall (42B) with respect to a height direction (AE). An outflow pipe (8) has: a first opening (8A) that connects an outflow passage (8R) with a muffling chamber (5) in the vicinity of a first main body wall (42A); and a second opening (8C) that connects the outflow passage (8R) with the muffling chamber (5) in the vicinity of a second main body wall (42B). The liquid staying on the first main body wall (42A) of a first muffler (4A) flows into the outflow passage (8R) through the first opening (8A). The liquid staying on a second main body wall (42B) of a second muffler (4B) flows into the outflow passage (8R) through a second opening (8C). Therefore, the symmetry of the first muffler (4A) and the second muffler (4B) is compatible with anti-corrosion.

Abstract: According to the invention, at least part of the edge of the hole is loosely surrounded with a mesh structure so as to create a space between the latter and said edge part.

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: An acoustically treated exhaust centerbody comprising a body including a body fore portion and a body aft portion. An internal passageway extends through the body in the axial direction. A resonator in the body fore portion includes a plurality of acoustic chambers. A plurality of ribs in the resonator form fore/aft walls of the acoustic chambers. Each rib is shaped substantially as a section of an annulus. A plurality of radial fins extend between adjacent ribs. The fins form sidewalls of the acoustic chambers. A skin overlies the acoustic chambers and forms an outer surface of the resonator.

Abstract: A component, such as an intake manifold or a throttle body, has an air passage. A structure may extend into the air passage so that the structure intersects a part of a total air-flow passing through the air passage. The structure may have a first through-hole and a second through-hole. Each of the through-holes define a cross-sectional area that may taper in a direction of air-flow that is passing through the air passage so that a cross-sectional area of an entrance of the respective through-hole is greater than a cross-sectional area of an exit of the respective through-hole. The structure helps attenuate acoustic noise that may occur in the component due to the air-flow.

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 low emissions 2-stroke natural gas fueled engine includes at least one cylinder with an exhaust port in communication with a silencer/catalytic converter unit. The unit has first and second volumes in communication with each other. The first volume dampens spurious exhaust pressure excursions and removes particulates in the exhaust. The second volume houses an oxidation catalyst for treating exhaust to reduce exhaust emissions. The engine oil has at most 10 ppm zinc content to reduce metal poisons contained in the exhaust prior to contact with the oxidation catalyst. The engine oil preferably has a very low ash content to minimize sulfur combustion components in the exhaust to reduce masking of the oxidation catalyst. The first volume preferably has a pressure relief valve set to relieve at a pressure greater than the maximum normal operating pressure of the engine to avoid excessive pressure excursions of the engine exhaust from damaging the oxidation catalyst.

Abstract: Methods and devices for increasing the sound attenuation properties of a noise suppression device are provided. Various embodiments include sound-attenuating cavities with improved sound capturing openings. In some embodiments, the sound capturing openings include holes surrounded by projections. In other embodiments, the sound capturing openings include angled slats. Embodiments also include sound capturing devices that include the improved sound capturing openings, such as silencers, vent hoods, barrier walls, air exchanges, and air intake and exhaust ducts.

Abstract: An auto-sensing, automatic adjusting exhaust baffle; for reducing noise emissions produced by internal combustion engines, while improving overall engine performance, i.e., torque and horsepower. The design uses a spherical shape to evacuate spent exhaust gas, thus scavenging the surrounding exhaust gases to adjust the backpressure, while reducing the noise exiting the exhaust pipe at lower rpm's. The device uses a sphere with an internal bearing; sliding linearly on a shaft and said sphere and bearing being acted upon by exhaust gasses and a compression spring mounted axially over the diameter of the shaft. The purpose of this device is to reduce noise while improving tuning of the air/fuel intake system, by adjusting backpressure of the exhaust system. The lesser amount of exhaust pressure, the less the sphere moves, as in idle to just off of idle, this results in a quiet operational mode of the invention.