Abstract: A muffler that uses baffles at a 45° relative to one another to create a helical configuration within the cylindrical housing allowing exhaust gases to pass more freely than the prior art mufflers, while maintaining superior noise reduction.

Abstract: A muffler for an exhaust system of an internal combustion engine, comprises a housing comprising a shell having an inner wall, an inlet pipe and an outlet pipe, the inlet pipe and the outlet pipe extending into an inner space of the housing, for conveying an exhaust gas stream into and out of the inner space of the housing, at least one baffle arranged in the inner space of the housing, the baffle comprising a baffle plate, the baffle plate having a circumference, and a baffle lip arranged at the circumference of the baffle plate, the baffle lip engaging the inner wall of the shell and having an end portion, wherein the end portion of the baffle lip is curved inwardly away from the inner wall of the shell.

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 power electronic device with cooling arrangement includes a housing that accommodates power electronic components. At least two adjacent axial fans are connected to the housing for inducing an airflow from outside into the housing in order to cool the power electronic components. Furthermore, the device can include a separating wall that extends outside the housing from between the at least two adjacent axial fans in order to reduce noise caused by the fans. Such a cooling arrangement can provide a power electronic device with effective cooling in compact size and also having an acceptable level of noise.

Abstract: An exhaust muffler device for an internal combustion engine includes an outer housing which defines a sealed chamber and which is connected to opposite inlet and outlet pipes, and an initial expansion subchamber and a pre-outlet subchamber disposed in the sealed chamber. The exhaust gas enters the initial expansion subchamber and mainly flows to a tubular passage in the pre-outlet subchamber to be exhausted through the outlet pipe. Portion of the exhaust gas flows into the sealed chamber and re-enters into a rejoining region of the tubular passage to be entrained in the main stream, thereby attenuating noise of the engine with minimal reduction of engine performance.

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 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 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 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 exhaust system for a vehicle, such as a motorcycle or other straddle-type vehicle, that achieves miniaturization while providing advantageous noise reduction characteristics. The exhaust system is associated with an engine of a vehicle and includes an exhaust pipe connected to the engine and a silencer. A conical member is positioned within the silencer and includes an upstream end and a downstream end. At least a portion of a side wall of the conical member includes a plurality of through-holes. The conical member is oriented such that a radial dimension of the conical member increases in a direction from the upstream end to the downstream end.

Abstract: A suction silencer in a compressor is disclosed, including a lower shell having an opened top, that draws refrigerant, and an upper shell fixed to the top of the lower shell to form an inside space that reduces noise of drawn refrigerant, and that discharges refrigerant in a direction different from a flow direction of the refrigerant introduced into the lower shell, thereby simplifying a structure to permit easy assembly.

Abstract: The present invention provides an air intake noise reducing device, an internal combustion engine fitted with the air intake noise reducing device and a structure for fitting the air intake noise reducing device to the internal combustion engine. The air intake noise reducing device comprises a gasket (2) comprising a ring member (2a) held by connecting surfaces of an air intake passage (100) and protrusion holding portions (2b) extending from the ring member (2a) toward a center of the air intake passage (100); and a net member (3) comprising a net (3a) for rectifying intake air and connecting protrusions (3b) extending outward from the net (3). The connecting protrusions (3b) are held in the protruding holding portions (2b) such that the ring member (3) is firmly secured to the gasket (3). The air intake noise reducing device constituted by in the above-mentioned manner can reduce assembly man-hours without deteriorating a sealing property of the air passage.

Abstract: In order to provide an exhaust muffler for an internal combustion engine, especially a portable implement, comprising a catalyst which is arranged in a housing which has at least one inlet opening and one outlet opening for exhaust gas flowing out from the internal combustion engine into the environment, in which the temperature of the exhaust gas in the area of the outlet into the environment is reduced substantially and/or a sufficiently long path length is made available so that flame development can be avoided especially in the outlet area of the exhaust muffler, it is proposed that the outlet opening has at least one means through which exhaust gas flows, which is arranged partially outside the housing and has an outlet facing the environment, whereby the flow path of the exhaust gas in the direction of the environment is lengthened.

Abstract: An exhaust system comprising: an exhaust chamber having a longitudinal axis and an outer wall defining alternating longitudinally-extending ribs and grooves; and an insert within the exhaust chamber, the insert including a plurality of fins extending generally perpendicular to the longitudinal axis, each fin including a distal edge extending substantially close to the plurality of ribs, the insert defining expansion chambers between adjacent fins. Pressurized gas flowing through the exhaust chamber flows along the grooves and expands within the expansion chambers to reduce the pressure of the pressurized gas prior to the gas exiting the exhaust chamber. The fins may in some embodiments be sufficiently stiff to resist substantial deflection under the influence of the gas.

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 system and method for dissipating at least one pressure wave in an exhaust gas flow is disclosed. A vehicular exhaust system directs the exhaust gas flow through a plurality of coaxial and perforated generally cylindrical tubes contained within an insulated canister towards a perforated partition plate. Through a series of apertures in the tubes and plate, the at least one pressure wave is dissipated such that sound attenuation is achieved without output loss from the engine.

Abstract: The improved muffler design has a housing that is hexagonal in shape that is formed from an upper plate, a lower plate and sidewalls that form a perimeter around the housing. An inlet and outlet are attached to opposite sides of the housing along the length. A primary vein is mounted within the housing with that allows some of the gases to around the vein and some of the gases to flow through holes in the leading surface of the primary vein. A secondary vein is mounted downstream of the primary vein and a mixing vein is mounted downstream of the secondary vein. The widest point more of the housing is closer to the than the outlet so the housing resembles a coffin.

Abstract: A reflecting plate type silencer pipe including a reflecting plate is provided for reducing a dominant frequency noise passing through a pipeline. Sound waves propagated in the pipeline as a one-dimensional plane wave are divided into two, that is, sound waves advancing straight along the pipeline and sound waves caused to pass through a bypass route by the reflecting plate thereby being delayed in phase. Both of the sound waves are joined again so as to synchronously advance in the same direction and in parallel to each other with the sound waves being the same in amplitude and opposite in phase to each other, and wave interference is effected between the sound waves, whereby wave propagation energy of the sound wave of the frequency to be silenced passing through the pipeline is selectively dissipated.

Abstract: A muffler comprising a multiplicity of plates, each plate having openings for directing gas flow is provided. The present invention's objective is to reduce engine noise while minimizing back pressure on the engine. It uses a series of plates with deflecting elements fixedly attached to the plates. These deflectors are intended to move the exhaust gases from a longitudinal motion to a cyclonic or swirling motion, so as to translate the gases longitudinal motion into a circular motion. This energy translation will reduce the gas' pressure as it exits the muffler and reduces the engine's noise, without the necessary use of sound absorbing materials or a resonating chamber.

Abstract: There is disclosed a silencer for attenuating sound waves produced in a fluid that circulates through a fluid conveyer. The silencer comprises an expansion chamber that is in fluid communication with the fluid conveyer, and which carries sound waves there through; a sound wave dissipater provided with the expansion chamber and arranged to absorb sound waves traveling there through; a resonator operatively associated with the sound wave dissipater and constructed and arranged to cause attenuation and reflection of the sound waves back and forth towards the sound wave dissipater; the expansion chamber having a chamber: conveyer cross-sectional area ratio and chamber length characteristics allowing maximum transmission loss for a given frequency. The expansion chamber has an exit to allow fluid containing attenuated sound waves to escape therefrom.

Abstract: A muffler assembly for a compressor that suppresses noise that would otherwise escape from the inlet of the compressor during its operation. The muffler assembly includes an intake conduit that has an inlet portion, an outlet portion adapted to couple to an inlet of a compressor, a longitudinal axis defined between the inlet portion and the outlet portion, and a passage defined through the intake conduit generally parallel to the longitudinal axis. A baffle is disposed in the intake conduit generally traversing the passage. The baffle is defined in a plane that is disposed at an angle with respect to the longitudinal axis. An opening is defined at least partially by the baffle and disposed generally proximate to the outlet portion of the intake conduit.

Abstract: A flow tube for an induction system with a turbo charger includes a first tube half and a second tube half with a noise attenuation plate positioned between the halves. The noise attenuation plate includes a plurality of holes having varying diameters and depths. The first tube half, the second tube half, and the noise attenuation plate are integrally formed as a single piece during an injection molding process. The noise attenuation plate is folding along a first living hinge to overlap one of the first or second tube halves. The other of the first or second tube halves is folded along a second living hinge to overlap the noise attenuation plate forming a flow tube that defines a flow path. The noise attenuation plate serves as a low pass filter that attenuates high frequencies while allowing lower frequencies through.

Abstract: A low noise method and apparatus with the apparatus including a hood for mounting over an exhaust outlet duct to capture a fluid stream and then redirect the fluid stream to a fluid outlet in the hood through the use of smoothly curving duct that maintains the fluid flowing therethrough in a laminar flow condition with the inlet and outlet positioned such that there is no line of sight between the exhaust outlet duct and the fluid outlet duct in the hood.

Abstract: A performance muffler suitable for installation into an exhaust system for an internal combustion engine wherein either end of the muffler may be designated as the entrance end for the receipt of exhaust gases into the muffler without materially altering the functionality of the muffler. A method is disclosed.

Abstract: A silencer for a vacuum cleaner is provided and includes at least one hermetic expansion chamber mounted in an exhaust channel of the vacuum cleaner and allowing an exhaust airflow from the vacuum cleaner to pass through. The expansion chamber at its two sides has an inlet and an outlet connected to the exhaust channel. A silencing board is mounted in the expansion chamber, separating the inlet from the outlet. Pores are distributed throughout in the silencing board. The silencer integrates several different silencing structures together, and, when mounted to the exhaust port of the vacuum cleaner, can considerably diminish the noise generated by the vacuum cleaner in operation.

Abstract: An exhaust system baffling apparatus is provided. The apparatus includes a tube with at least one end that is not open. The apparatus further includes a plurality of C-shaped flanges in surrounding relation about the tube. The outer edges of the flanges have a contour which generally corresponds to a contour of an inner surface of a wall of an exhaust pipe. Opposed portions of the flanges adjacent the slits of the flanges are spread apart along the tube in a longitudinal direction. In addition, the opposed portions of the flanges adjacent the slits are angled in opposite directions and extend radially from the tube at a non-perpendicular angle with respect to the tube. At least two of the flanges include brackets adjacent the outer edges of the flanges, wherein the brackets are adapted for securing the apparatus to an interior portion of the exhaust pipe.

Abstract: The current invention is device for lowering the air velocity and inherent noise of high-speed air released from a closed system, comprising a straight pipe module with an outer tube and a concentric inner tube creating an annular space therebetween. The inner tube has interior fins at the inlet, which initiate rotation in an airflow directed therethrough, and interior fins at the outlet, which arrest the airflow rotation. Perforations along the length of the inner tube, from inlet fins to outlet fins, permit the release of a turbulent outer zone of the airflow, permitting the high velocity core of the airflow to expand and slow, reducing the noise of the airflow.

Abstract: A muffler includes an outer shell which defines a chamber. A baffle is positioned in the chamber. A pair of plates cooperate with the baffle to partition the chamber into subchambers.

Abstract: In-line exhaust systems comprise an exhaust pipe, and a sound-attenuating baffle in the exhaust pipe. The baffle has one or more baffle plates extending across the gas flow channel, at least one at an oblique angle. Each plate has an array of apertures therethrough. The plates are joined to each other, preferably in edge-to-edge relationship, preferably forming included angles with each other and forming preferably different, oblique angles to the longitudinal axis. In preferred embodiments, plate aperture area increases, plate-to-plate, along the direction of advance of gases in the exhaust system. A backwash valve can lie over one of the baffle plates. The exhaust system can include a water jacket, and optionally an outer sound attenuation chamber. The baffle is preferably 36 or less inches long, the exhaust system reducing noise by at least 3 decibels.

Abstract: In-line exhaust systems comprise an exhaust pipe, and a sound-attenuating baffle in the exhaust pipe. The baffle has one or more baffle plates extending across the gas flow channel, at least one at an oblique angle. Each plate has an array of apertures therethrough. The plates are joined to each other, preferably in edge-to-edge relationship, preferably forming included angles with each other and forming preferably different, oblique angles to the longitudinal axis. In preferred embodiments, plate aperture area increases, plate-to-plate, along the direction of advance of gases in the exhaust system. A backwash valve can lie over one of the baffle plates. The exhaust system can include a water jacket, and optionally an outer sound attenuation chamber. The baffle is preferably 36 or less inches long, the exhaust system reducing noise by at least 3 decibels.

Abstract: Disclosed is a muffler in which a helicoil member is installed in each conduit, through which refrigerant gas flows from or into an expansion chamber during reciprocating movements of a piston in a cylinder. The helicoil member has diverse twisted angles and diverse twisted shapes, and serves to divide pulsation of noise, generated during the reciprocating movements of the piston, into pulsation of different phases, and then to merge the divided pulsation together, while allowing the refrigerant gas to have the form of a vortex flow. As pulsation of noise generated during an operation of sucking refrigerant gas pass along different travel paths defined by the helicoil member, a mutual interference occurs between the pulsation respectively emerging from the travel paths of the helicoil member. Therefore, an increased offset effect for the pulsation of noise is obtained, which maximizes a noise attenuation effect.

Abstract: A high-pressure hose includes a rubber tube, a pair of steel tubes connected to each end of the rubber tube, and a pulsation damping member installed in the rubber tube, one end of the damping member being fixed in the steel tube connected to a downstream end of the rubber tube by means of a ring.

Abstract: More than two damping chambers 2A to 2C), a communicating pipe (6) for intercommunicating the damping chambers (2A, 2B) and another communicating pipe (7) for intercommunicating the damping chambers (2B, 2C) are provided. Both ends of the communicating pipes (6, 7) are closed by an end plate (9) and the respective damping chambers (2A to 2C) and inside of the communicating pipes (6, 7) are intercommunicated by communicating holes (8A) on an outer circumference of the communicating pipes (6, 7). Exhaust gas flows from the damping chamber (2A) to communicating holes (8A1), inside of the communicating pipe (6), communicating holes (8A2), the damping chamber (2B), communicating holes (8A3), inside of the communicating pipe (7), communicating holes (8A4), and the damping chamber (2C), thus damping exhaust noise by repeated effective contraction and expansion.

Abstract: A muffler (10) having a casing (21), an inlet opening (22) and an outlet opening (26). An initial partition (30) forms an expansion chamber (28). The casing (21) has mounted and formed therein a partition array (34) that includes a divider partition (36), a first intermediate partition (38), and a second intermediate partition (40). Partition array (34) is positioned in a main sound attenuation chamber (46). A collector partition (42) having a collector opening (44) is positioned between array (34) and opening (26). A pre-outlet chamber (48) is formed by collector partition (42) prior to outlet (26).

Abstract: A sound attenuating device is provided for use in reducing sound levels associated with a sound source, such as an internal combustion engine. The noise attenuating device, for example, is connected to the exhaust pipe of the engine and receives sound waves and a fluid flow of exhaust gas therefrom. The sound attenuating device includes a housing which defines an interior chamber, an inner deflector assembly extending centrally through the chamber, and a diverter arrangement near an inlet of the housing. The inner deflector assembly is formed from a longitudinal stack of spaced apart tapered deflectors such as inner cones which extend centrally through the chamber and define an annular passage radially between the inner cones and the housing wall. The diverter arrangement diverts the fluid flow to the annular passage.

Abstract: A catalytic converter for stand-alone application or for use with a novel silencer. The silencer includes a catalytic converter formed from a central housing of a size to house at least one catalytic converter element, an inlet portion connected to the inlet side of the central housing and an outlet portion connected to the outlet side of the central housing. The silencer is formed from a cylindrical housing which is secured on one end to the catalytic converter and on the opposite end to an exhaust pipe of an internal combustion engine. The cylindrical housing has at least one baffle plate transversely mounted therein. The baffle plate has a plurality of perforated conical members positioned opposite each other on each side of the baffle plate. The perforated conical members redirect the flow of exhaust gas through the silencer.

Abstract: A sound absorber for jet engines and the like including a housing defining an inflow opening and an outflow opening. Sound absorbing elements positioned within the housing define substantially parallel entrance and exit planes. The sound absorbing elements include a plurality of gas guidance and baffle elements in two spaced-apart and parallel row-like arrangements, the elements having U-shaped, V-shaped, or semicircular cross-sections. The rows of sound absorbing elements are offset and the elements arranged such that the opened cross-sectional areas face each other in overlapping fashion. The entrance plane and the exit plane are inclined relative to an entrance flow through the inflow opening within an angular range of between 0.degree. to less than 90.degree..

Abstract: A sound attenuating muffler useful with an internal combustion engine, preferably for marine applications, contains an insert comprising an arrangement of annular sound reflecting surfaces defining an inner chamber into which engine exhaust gases flow in a first direction and one or more directors to divert the axial flow of gases and sound waves in a second direction past these sound reflecting surfaces. As the sound waves are reflected off of these surfaces back into the muffler interior, attenuation of the sound is achieved. One or more additional inserts may be placed downstream from the first insert for additional sound attenuation. Each of the inserts may be in the form of discrete sound reflector rings or as a continuous helix. A method of assembling the component parts of the insert is also described.

Abstract: An improved aircraft muffler and the method of making it is disclosed. It is a plug muffler design having an outer housing and an internal exhaust conduit. The exhaust conduit has a center partition that blocks the flow of exhaust gas through the conduit. A number of holes are formed through the conduit wall such that the exhaust gas passes out through the holes on the inlet side of the partition and reenter the conduit on the outlet side of the partition. Unlike previous designs, the holes formed in the exhaust tube of the muffler are not flat and do not have hoods. Rather they have formed surfaces that slope. The formed surfaces both protrude above and below the exhaust tube wall. Thus the formed surface creates a directional flow path for the airflow to help increase the velocity, which consequently helps to move exhaust gases through the baffle as opposed to straight holes. The indented holes serve another purpose.

Abstract: A muffler for an internal combustion engine or the like including a casing (21) having an inlet opening (28), an outlet opening (29), a first partition (43) secured in the casing (21) to divide incoming exhaust gases, and a second partition (46) secured in the casing (21) downstream of the first partition (43), which second partition (46) has an opening (39) through which the divided exhaust gases are converged and joined together for exiting the casing (21). The improvement in the muffler assembly which produces both sound attenuation and lower operating back pressure is to provide an intermediate partition (51) secured in the casing between the first and second partitions (43,46) which is formed to permit substantially uninterrupted or unimpeded flow of exhaust gases past the intermediate partition, while a forwardly facing concaved surface (52) reflects sound components in a direction away from the opening (39) in the second partition (46).

Abstract: A sound attenuating muffler useful with an internal combustion engine, preferably for marine applications, contains an insert comprising an arrangement of annular sound reflecting surfaces defining an inner chamber into which engine exhaust gases flow in a first direction and one or more directors to divert the axial flow of gases and sound waves in a second direction past these sound reflecting surfaces. As the sound waves are reflected off of these surfaces back into the muffler interior, attenuation of the sound is achieved. The gases exit the muffler to the atmosphere through an outer chamber surrounding the inner chamber. A method of assembling the component parts of the insert is also described.

Abstract: A muffler for impeding and reflecting exhaust to reduce the formation of sound waves through a plurality of cone and barrier assemblies alternately and longitudinally spaced in a cylindrical body, with the apex of a conical member of each cone assembly and an outwardly extending cylindrical portion of each barrier assembly being directed towards the input end of the body. Exhaust flow paths for dissipating exhaust noise are defined by orifices formed in the conical members and cylindrical portions, and spaces between spokes joining each conical member to a circular member.

Abstract: A compact, sound-attenuating muffler for an internal combustion engine is disclosed in which the muffler includes a stream dividing partition positioned proximate the inlet of the muffler to divide the incoming exhaust gases into two streams of substantially equal volume. The stream dividing partition directs the streams laterally of the inlet in directions diverging from each other, and the muffler sound-attenuating assembly further includes corridor defining partitions receiving the streams from the stream dividing partition and maintaining the streams in corridors as coherent substantially eddy-free streams. The corridor defining partitions further direct the streams laterally to converge towards each other for discharge of the coherent streams against each other from opposed directions in a common volume inside the muffler casing. Further sound attenuation is accomplished by a common channel receiving the streams after they are intersected or discharged against each other.

Abstract: A muffler is disclosed comprising a closed housing having an annular inlet and an annular outlet neck, and the housing having arranged therein a pair of axially extending pipes which are at least partially overlapping one another. One of the pipes is connected to the inlet neck and has a circumferentially arranged passageway to permit the exhaust gases to be directed from the inlet neck to the inside of the housing. The other pipe is connected to the outlet neck and has a circumferentially arranged passageway to permit the exhaust gases to be directed from inside the housing to the outlet neck.

Abstract: A device for attenuating pulsation of a fluid in a piping system comprises fluid-branching pipes extending from the piping system in which there are pulsation waves, and a plurality of orifice elements and a plurality of discs disposed in a dispersed fashion and having a small reflection factor of the pulsation wave and having a total friction factor greater than that of the entire piping system, thereby providing the effect of attenuating the pulsation of the fluid within the system without increasing the resistance of the piping system without increasing power consumption.

Abstract: A plug section for a muffler, including an outer body and having an inlet pipe for introducing exhaust gas into the body. The inner end of the inlet pipe located within the body portion is closed off. Surrounding the inlet pipe is a conical baffle having a small diameter end secured to the inlet pipe to provide a tapered chamber between the inlet pipe and the conical baffle, while the space between the conical baffle and the outer body defines an outer chamber. Both the inlet pipe and the conical baffle are provided with a plurality of perforations. Exhaust gas entering the inlet pipe flows outwardly through the perforations in the inlet pipe to the tapered inner chamber and then flows through the perforations in the conical baffle to the outer chamber. The use of the perforated conical baffle provides a substantial improvement in sound attenuation, reducing both the shell noise level and the outlet noise level.

Abstract: A sound suppressor for a firearm, including a hollow cylindrical casing having an entrance end and an exit end; and at least one disc-shaped baffle element coaxially mounted within the casing and between the ends. The element has front and rear faces with an annular area therebetween and at least one opening in its rear face. A centrally apertured entrance end plug is attached to the entrance end of the casing and is mountable to the muzzle of a firearm. A centrally apertured exit end plug is attached to the exit end of the casing. The baffle element has a primary opening therethrough with at least one slanted sidewall and at least one secondary opening arranged between the annular area and the slanted sidewall.

Abstract: A silencer for the barrel of a firearm comprises a sheath defining an interior space having open opposite ends. The sheath has a longitudinal axis. A plurality of partitioned plates are connected to the sheath and extend across the interior space thereof. Each partition plate has an opening therethrough of a size which is wider than a caliber of the firearm barrel and which lies in a plane which is inclined at an acute angle with respect to the axis. Each partition plate, in a direction along the axis, is rotated around the axis by a selected angle with respect to a previous partition plate to produce a convoluted path for gases discharged from the gun barrel. The first partition plate in the sheath adjacent a firearm valve which is connected to one open end of the sheath, defines an initial expansion chamber for the gases.

Abstract: A compact, sound-attenuating muffler for a high-performance internal combustion engine is disclosed in which the muffler casing has an elongated transverse cross-section with a height dimension of only slightly larger than the height dimension of the inlet exhaust pipe and a width dimension in the range of about 2 to 41/2 times the height dimension. The muffler includes a divergently tapering planar first partition which causes gases to be expanded only in a horizontal plane toward the side walls of the muffler and further includes a second partition formed to contract or converge the gases in a horizontal plane toward a central opening. The first partition has a cup-shaped back surface so that contraction of the gases around the back side of the first partition is highly effective in attenuating sound, and both partitions are sloped in a direction toward the outlet from the muffler so as to minimize the generation of back pressure, which is not substantially greater than the back pressure in a straight pipe.

Abstract: A muffler for dissipating the sound component in exhaust gases from an internal combustion engine or the like is disclosed which has an enhanced useful life. The muffler includes a partition positioned across an incoming stream of exhaust gases. The partition is formed with stream dividing or splitting means which positively divides the stream into portions that can be more evenly directed throughout the muffler. This prevents destructive preferential flow of gases within the muffler. Additionally, shielding of sound absorption material in the muffler is accomplished by selecting the pattern of perforations to reduce the contact of such material with high velocity gases.