Abstract: A muffler for muffling engine operating sound and including a double-walled cylindrical shell closed at opposite ends by double-walled closure caps. The space between the shell walls is filled with sound-absorbing solid particles. The shell is partitioned into three axially contiguous chambers. A gas charging pipe projects through one closure cap and axially within the shell, and has two pairs of facing discharge elbows for discharging gas from the charging pipe at locations in the first chamber. A first pair of gas transfer pipes extends from the first chamber into the central chamber to points of opposed gas discharge. A second pair of gas transfer pipes extends from the central chamber into the third or discharge chamber, and from this location, the gas passes out of the muffler via a discharge pipe.

Abstract: A physical shape-conformable, disposable, self-sustaining sound dampening unit adapted to attach to the air exhaust of a pair of electric motors to dampen the noise produced by the same, which comprises:a body member formed of a thin imperforate film outer layer and a polymer foam inner layer lining the interior of said body member and having two inlet ports and at least one outlet port, the body having an interior pathway between the inlet ports and the outlet port, said inlet and outlet ports being disposed so that the incoming airstream impinges on an interior closed foam covered wall of said body and is made to turn at a right angle before reaching said outlet port.

Abstract: A catalytic converter of the automotive type comprising a reduced central oval section that compresses a support mat around a catalyst substrate, the reduced central section comprising radially inwardly biased ribs that are parallel to the longitudinal axis of the converter.The converter can be made by inserting a catalyst substrate and surrounding support mat through the open end and into the central portion of an oval sheet metal tube, after which the reduced section and longitudinal ribs are formed in the central portion of the tube to compress the mat and securely engage the substrate, and the ends of the tube are pinched together to form sealed end closures with gas flow passages therein.

Abstract: In a process for the manufacture of an exhaust silencer for motor vehicles, the advantages derived from employing mineral fiber mouldings are extensively retained while at the same time greatly reducing expenditure on shape-stabilization and transportation. To this end the silencer casing itself is divided in the meridian plane and the mineral wool is supplied and inserted directly into the original silencer casing in the form of precisely dimensioned prefabricated elements which have been impregnated with a suitable fluid, for example pretreated with synthetic resin, but not cured. This enables fast and reliable positioning of the impregnated and manually compressed prefabricated elements around the periphery of the exhaust pipe and the internal component containing the exhaust pipe inside the original silencer casing; once the silencer casing has been closed, the silencer is ready for installation. Curing, hardening or some other time consuming method of shape-stabilization is not necessary.

Abstract: A muffler system for a working vehicle, particularly a lawn mower, comprising a main muffler body connected to an exhaust manifold of the engine, and a curved muffler cover covering the main muffler body from below. An exhaust pipe extends from the main muffler body laterally outwardly of the vehicle body, and defines an exhaust outlet for discharging exhaust gas in a direction away from a front wheel and the ground. Cooling air is blown by a cooling fan from the engine into the muffler cover. The muffler cover defines air exhaust openings for directing the cooling air forwardly of the vehicle body.

Abstract: An exhaust gas muffler has a housing composed of upper and lower press-formed parts with two chambers and a gas passage means composed of upper and lower plates with three parallel press-formed troughs defining a tri-flow gas path wherein one of said chambers serves as a turn-around from the gas path and the other of said chambers receives said troughs and is acoustically connected to the gas path through perforations in the walls of the troughs.

Abstract: A muffler is constructed to have a tubular perforated plate within its cavity so as to divide the cavity into an outer resonant cavity and an inner resonant cavity, to thereby provide two resonant frequencies. The tubular perforated plate is formed in the shape of a funnel.

Abstract: A muffler is provided with a pair of plates formed to define an array of tubes therebetween. At least one external shell is secured to at least one of the plates to surround selected portions of the tubes. The shell is formed to define a plurality of chambers separated from one another by a baffle crease. The baffle crease is parallel to and abutting a selected tube of the muffler to simplify the draw of metal material in the vicinity of the baffle crease and to thereby save metal. The baffle crease is of substantially uniform depth along a major portion of its length and is free of pockets that could conceivably retain corrosive fluids.

Abstract: A muffler includes an outer box fitted over and attached to an exhaust pipe. The muffler also has a connecting member of a noncircular cross section fixed to said exhaust pipe and interposed between the exhaust pipe and the outer box.

Abstract: An improved muffler of relatively large size for internal combustion engines is shown, which comprises a main hollow shell, assembled from half sections with caulked flanges to join the sections together into an airtight enclosure, at least one perforated baffle plate having its periphery clamped between the opposite edges, exhaust inlet and outlet ports. The baffle plate is bent into a curve defining in the inside of the shell chambers differing in volume from one another, through which the exhaust gases from an engine are forced to flow so that the gases alternately expand and contract. In addition to the rigid integration of the baffle plate with the shell by caulking, various interlocking and elastic members rigidly interconnect between the plate and the inside walls of the shell in such a manner as to reduce development or transmission of the vibrations in the shell components due to the pressure oscillations of the exhaust gases.

Abstract: A muffler for an internal combustion engine comprises: a communicating passage constituting member allowing a plurality of chambers formed by partitioning walls inside an outer shell to be communicated with each other; and a butterfly-type valve provided in the communicating passage. The communicating passage constituting member is formed into the shape of a gutter so as to face either an inner surface of the outer shell at an open side of the constituting member or an outer surface of the outer shell at an open side of the constituting member. Alternatively, the communicating passage constituting member is constituted by a pipe and is provided in the outer shell. The arrangement makes it possible to improve the engine output, reduce the back pressure, and enhance the sound-damping effect.

Abstract: A stamp formed muffler includes upper and lower internal plates and upper and lower external shells secured to the respective internal plates. The internal plates are formed to include arrays of channels that are placed in register with one another to define an array of tubes. The external shells are formed to define chambers that surround selected tubes formed by the internal plates. The upper internal plate includes at least one pair of aligned channels disposed in spaced apart end-to-end relationship and in register with a continuous channel in the lower internal plate. The chambers of the external shells are separated from one another by baffle creases. The baffle crease of the upper external shell is disposed in registration with the spaced apart aligned channels of the upper external shell. As a result, the baffle crease of the upper external shell is substantially free of pockets that conceivably could trap foreign materials.

Abstract: An automotive exhaust gas muffler comprises gas passage tubes supported in curved portions of two press-formed metal housing parts and communicate with recesses formed in the housing parts.

Abstract: A muffler assembly includes a pair of outer shells mating to define a muffler chamber and a pair of internal tuning plates mating to define inlet and outlet tubes in the muffler chamber. Drop-in baffles are used to divide the muffler chamber into an expansion chamber, a pair of exhaust turnaround chambers, and a pair of resonance chambers. The two outer shells and first tuning plates are mechanically locked together at the perimeter of the muffler assembly and the second tuning plate is piggybacked onto the first tuning plate to reduce the number of material layers included in the mechanical lock. Each of the outer shells includes one or more ribs and channels for stiffening the outer shell to reduce vibration noise and to conduct condensate developing in the muffler chamber either to a hotter region where it will vaporize or to a drain.

Abstract: A silencer for the exhaust gas of motor vehicle internal combustion engines is proposed comprising an outer wall having in its upper part a deformable zone, preferably in the form of a transverse indentation, which provides preferential deformation under impact, and if a rear impact occurs prevents the silencer from rigidly striking the most inner structure of the vehicle floor and the fuel tank.

Abstract: A muffler is provided comprising an array of tubes and a stamp formed external shell surrounding the tubes. The external shell is stamp formed to define at least one chamber surrounding at least portions of the tubes. The chamber extends away from peripheral portions of the external shell to define a three-dimensional volume. The chamber is characterized by a plurality of inwardly directed V-shaped grooves, with each groove extending continuously between opposed spaced apart locations on the periphery of each chamber. The grooves preferably define a parallel array of substantially identical grooves. The grooves strengthen the walls of the chamber and efficiently prevent shell noise.

Abstract: An exhaust tube capable of having a better silencing effect without adversely affecting the horsepower output of an engine is provided. The exhaust tube includes a tube body having two end plates, two spaced disks dividing the tube body into three gas chambers and a pipe having an expanded first end, a first horizontal portion, an inclined portion having a verturi tube, a perforated second horizontal portion, and a second opposite free end.

Abstract: A stamp formed exhaust muffler for mounting on a vehicle is provided. The muffler comprises a plurality of plates secured in juxtaposed relationship and stamp formed to define an array of tubes therebetween. At least one external shell is secured to the internal plates to define at least one chamber which communicates with the array of tubes. The external shell includes at least one conformal area which permits the muffler to conform to the shape of a structure on the vehicle. The conformal area may be an area of generally arcuate concavity when viewed from the exterior of the muffler or may define an internal corner on the muffler. Thus, a plane or line connecting two locations on the conformal area of the external shell will pass through the interference zone of a structure on the vehicle. The conformal area may be disposed where peripheral edges of the formed components are joined.

Abstract: A light weight exhaust muffler is provided comprising a pair of formed external shells and a pair of pipes disposed therein. The external shells are formed to include peripheral portions and chambers extending from the peripheral portions. The chambers are separated from one another by baffle creases unitary with the respective external shells. Portions of the baffle creases of one external shell are secured in face-to-face contact with corresponding portions of the baffle creases in the other external shell. The baffle creases comprise arcuate portions corresponding to the shape of the pipes passing between the chambers separated by the baffle creases.

Abstract: A light weight exhaust muffler is provided comprising a pair of formed external shells and a pair of pipes disposed therein. The external shells are formed to include peripheral portions and chambers extending from the peripheral portions. The chambers are separated from one another by baffle creases unitary with the respective external shells. Portions of the baffle creases of one external shell are secured in face-to-face contact with corresponding portions of the baffle creases in the other external shell. The baffle creases comprise arcuate portions corresponding to the shape of the pipes passing between the chambers separated by the baffle creases.

Abstract: A system of stamp formed mufflers is provided. Each muffler in the system includes a pair of plates formed to define an array of tubes therebetween. At least one external shell is securely affixed to at least one of the plates to surround the tube. The mufflers in the system have generally the same pattern of tubes therein. However selected mufflers in the system have portions which are different from other mufflers in the system depending upon the acoustical requirements of the particular muffler in the system.

Abstract: A combined catalytic converter and muffler is provided. A catalyst is securely mounted in a canister which in turn is mounted intermediate a pair of formed internal plates. The plates are further formed to define an array of tubes therebetween. The tubes comprise an inlet to the muffler and an outlet from the muffler and communicate with the inlet and outlet of the catalytic converter. Selected tubes may have perforations or other apertures through which exhaust gases may communicate. At least one external shell is mounted to the assembled internal plates. The external shell is formed to define a plurality of chambers which communicate with apertures in the internal plates.

Abstract: The invention is directed to an exhaust gas muffler for a two-cycle engine, especially for a handheld portable tool, such as a chain saw. In exhaust gas mufflers equipped with a catalyzer, the formation of flame from the fuel-containing exhaust gases exiting from the muffler must be prevented. These exhaust gases are intensely overheated because of the exothermal process in the catalyzer. The muffler according to the invention includes a catalyzer which establishes a connection between separate component chambers of the muffler housing. The muffler can be mounted directly on the motor outlet.

Abstract: A muffler includes a cylindrical body, a gas passage pipe insertedly mounted within the cylindrical body, and a sound absorber mounted upon the gas passage pipe in an encircling manner. Gas is discharged from the gas passage pipe through the cylindrical body and sound absorber. The cylindrical body has a disk-like partitioning wall axially dividing the interior space thereof. The gas passage pipe has an outer flange and a plurality of pawls cooperating with the flange so as to clamp the partitioning wall therebetween.

Abstract: An exhaust muffler for use with an internal combustion engine has at least one internal suppression chamber, at least one inlet pipe for receiving exhaust gases from the internal combustion engine, and at least one outlet pipe vented to atmosphere. The exhaust muffler comprises a plurailty of component units connected in series with each other and each having the internal suppression chamber. Each of the component units has a casing having an inner layer of a sound-absorbing material which defines the internal suppression chamber, and a connector pipe connected to and extending through the casing, the connector pipe having upstream and downstream ends projecting out of the casing, the connector pipe having at least one opening which opens into the internal suppression chamber.

Abstract: The invention relates to an exhaust gas muffler for a two-stroke engine of a portable handheld tool such as a chain saw. The exhaust gas muffler includes a catalyzer wherein high exhaust gas temperatures are developed because of the exothermal reaction which takes place therein. The catalyzer is located in the forward portion of a gas-tight hollow body mounted in the housing of the muffler. The hollow body has a tapered portion which extends out of the housing in the direction of the exhaust gas flow. In this way, the surface temperature of the muffler housing is reduced.

Abstract: A flat, box-like muffler formed of metal upper and lower housing sections and internal gas passage defining plates has drainage holes to allow liquid that collects on the top of the muffler or on the bottom of the lower section inside the housing to drain out of the muffler. A special sound attenuation structure comprising passages pressed in the plates and support channels in the housing sections is shown.

Abstract: A stamp formed muffler is provided with a nonplanar array of tubes. The tubes are defined by at least one pair of nested formed members. The nested members include at least one external shell having a nonplanar portion and at least one internal plate having a nonplanar portion, with the respective nonplanar portions being configured to be placed in generally nested face-to-face relationship. The nonplanar configuration comprises an array of channels, such that an array of tubes is defined by the channels when the components are placed in nested relationship to one another. One or more chambers of the muffler are defined adjacent the nested formed members. The chambers may be defined by a single plate placed in register with the nested components or by a second pair of nested members. The nested pairs of formed members is effective in dampening shell noise attributable to vibration of the formed members.

Abstract: A kit includes a self-contained muffler which attaches to the output exhaust system of a small two-cycle engine, such as a model engine that is in the range of 0.15 to 1.25 cubic inches displacement. The kit provides a low cost adaptation of existing engine manifolds to meet required sound reduction guidelines of below 90 Db at nine feed from the engine. The kit is easily adapted and installed on a wide variety of manifold-muffler adaptations, for example model engines using a mounting bolt which clamps the kit muffler to a portion of the existing engine muffler.

Abstract: An exhaust muffler for an internal combustion engine, comprising a hollow casing defining a plurality of chambers which are communicated with each other by way of small holes, an exhaust inlet tube fixedly attached to an exhaust port of an internal combustion engine at its one end and fitted into the casing from a hole provided therein for communication with one of the chambers at its other end, and an exhaust outlet passage communicating another one of the chambers to the atmosphere. The internal end of the exhaust inlet tube and an opposing casing wall are joined by a threaded fastener while the exhaust inlet tube is provided with an annular shoulder surface which fits into the hole of the casing in an air tight fashion, so that the mounting of the muffler can be accomplished simply by fitting the casing of the muffler onto the exhaust inlet tube which is typically attached to a cylinder head of an internal combustion engine in advance and tightening the threaded fastener.

Abstract: The silencer according to the invention contains two chambers (10,11) separated by a partition wall (14) and includes also a guide plate (25) guiding cooling air from a fan (27) through a channel (26) in which recesses (23) from one chamber terminate. By means of an ejecting function, then being formed, exhaust gases are evacuated into the channel and mixed with the cooling air to a lower temperature.

Abstract: A marine engine (18) is provide with a multi section injection molded thermoplastic air box (24) directing air to the fuel system's air intake throat (22) and silencing engine noise emitted back through the throat. The air box has a cover section (28) and a base section (26) mounted to each other solely by a seal (30) along a peripheral seam around the entire perimeter thereof, to prevent fuel leaks. The housing sections are preassembled to each other prior to mounting to the air intake throat. A removeable plug (70) in the cover section allows access through the cover section to bolts (56, 58) mounting the base section to the throat. Access is also enabled to a fuel adjustment screw (74) to enable adjustment, with the air box fully assembled and mounted in place on the throat, to enable adjustment under actual operating conditions. Air guide passages (32, 34) and an air plenum chamber (36) are all molded in place.

Abstract: Disclosed is an automobile muffler having a drain pipe communicating with the upperstream, upper half inside sound-deadening area of its outer pipe, thereby allowing the moisture of the air drawn into the sound-deadening space to leave for the surrounding atomosphere via the drain pipe prior to condensation of the moisture to water in the sound-deadening space, thus making it unnecessary to drain water from the muffler.

Abstract: A stamp formed muffler comprising a pair of internal plates and a pair of external shells is provided. The internal plates are stamp formed to define first and second spaced apart arrays of tubes and a single intermediate tube therebetween. Tubes in one array may have perforations or apertures to permit expansion of exhaust gases, while the other array may define at least one tuning tube. The tubes are disposed on the internal plates such that at at least one location thereon a straight line extending entirely across said internal plates will intersect only the one intermediate tube. The external shells are stamp formed to define a plurality of chambers which cooperate with the tubes in the internal plates. The chambers are separated from one another by a crease disposed to align with the intermediate tube. The crease is characterized by a single outwardly convex portion to engage the single bulb. As a result, the crease is not provided with recesses that conceivably could retain corrosive materials.

Abstract: A muffler for use with an internal combustion engine or the like having improved attenuation capabilities together with lower back pressure. The muffler has an elongated outer casing and an inner casing, the tubular ends of which extend beyond the outer casing for inlet, and outlet conducts. The central portion of the inner casing forms a continuation between the ends and has a differently configured but substantially equal cross-sectional area as the ends. The outer casing forms a sealed relationship with the inner casing adjacent the ends thereof. The central body portion is configured to have a portion in contact with the outer casing and a portion spaced from the outer casing. The surface of the spaced portion is perforated and sound absorption material is positioned in the space between the inner and out casing.

Abstract: A muffler cover has a plurality of air holes formed therein. At least part of the air holes is formed in such a manner as to have configurations which indicate characters or symbols, and at least those portions of the muffler facing the portions of the muffler cover that correspond to the air holes indicating the characters or symbols are coated with a heat resistant coating.

Abstract: A stamp formed exhaust muffler for mounting on a vehicle is provided. The muffler comprises a plurality of plates secured in juxtaposed relationship and stamp formed to define an array of tubes therebetween. At least one external shell is secured to the internal plates to define at least one chamber which communicates with the array of tubes. The external shell includes a conformal area which permits the muffler to conform to the shape of a structure on the vehicle. The conformal area may be an area of generally arcuate concavity when viewed from the exterior of the muffler or may define an internal corner on the muffler. Thus, a plane or line connecting two locations on the conformal area of the external shell will pass through the interference zone of a structure on the vehicle.

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: This invention is directed to the use of particularly defined epoxy-amine compositions as a protective coating on metals which are exposed to a high temperature, corrosive environment. The metal may be that employed in motor vehicle exhaust system components, such as mufflers and tailpipes. The epoxy-amine compositions comprises epoxy resin component, aromatic amine component, optionally, acid component selected from polycarboxylic acid and anhydrides thereof and optionally, polyol component.

Abstract: A muffler is provided with a pair of internal plates stamp formed to define an array of tubes therebetween. An external shell, which may be stamp formed, surrounds and encloses at least selected portions of the internal plates. The array of tubes stamp formed in the internal plates includes at least two tuning tubes. One tuning tube terminates at a tuning aperture in one of the two internal plates, while the other tuning tube terminates at an aperture stamp formed in the other of the two internal plates. Thus, one tuning tube will communicate with a low frequency resonating chamber on one side of the pair of internal plates, while the other tuning tube will communicate with a low frequency resonating chamber on the opposite side of the assembled internal plates.

Abstract: An exhaust muffler is provided. The muffler may be formed from a pair of internal plates that are secured in registration with one another and are formed to define an array of tubes through which the exhaust gages may travel. Selected portions of the tubes in the internal plates may be formed to include perforations. The muffler may further include at least one external shell formed to define at least one chamber which may at least partly surround the perforations in the internal plates. At least one inlet or outlet may lie on the seam between the formed plate members. However, at least one inlet or outlet may also be provided through a portion of the muffler spaced from the seams. The inlet and/or the outlet may be angularly aligned to the longitudinal axis of the muffler and may further be angularly aligned to one another.

Abstract: A muffler is provided including a pair of internal plates formed to define an array of tubes. At least one external shell is formed to define at least one chamber which will surround and enclose a selected portion of the array of tubes. Selected portions of certain tubes will be formed to include perforations. Portions of certain tubes will further undergo cross-sectional changes to control the flow of exhaust gases through the muffler. Certain channels between adjacent chambers of the external shell will be disposed to extend substantially continuously from peripheral portions of the adjacent chambers formed in the external shell. In certain embodiments, a controlled communication is provided between a low frequency resonating chamber and an adjacent expansion chamber. In other embodiments, additional formed layers are provided to enhance either heat or noise insulation.

Abstract: A sound attenuation apparatus which is to be connected to an airflow duct and is to receive the air from the duct. The sound attenuation apparatus includes a mass of plates located in a stacked arrangement with peripheral gaps being formed between the plates. The airstream is to be conducted through an opening formed between the plates. The airstream is to be conducted into an opening formed within the center of the plates and then discharged into the ambient through the peripheral gap area. Each of the plates include a mass of holes.

Abstract: A muffler is provided with a pair of stamp formed internal plates and a pair of stamp formed external shells. The internal plates define inlet and outlet tubes at least portions of which are provided with arrays of perforations or louvers. One or more tuning tubes may be stamp formed in the internal plates and one or more low frequency resonator chambers may be stamp formed from portions of either the internal plates or the external shells. The external shells may further be configured to define high frequency tuning chambers of a selected size and shape.

Abstract: A noise-suppressing air intake for a ventilation fan comprising a base having at least one sidewall and an open top and a cap positioned over the base with a portion of the cap being aligned with a portion of the base, and another portion of the cap overlapping a portion of the sidewall of the base to define a downwardly-facing, shielded air inlet therebetween. An air outlet is located in the aligned portions of the cap and base.

Abstract: A muffler is provided with a pair of stamp formed internal plates and a pair of stamp formed external shells. The internal plates define inlet and outlet tubes at least portions of which are provided with arrays of perforations or louvers. One or more tuning tubes may be stamp formed in the internal plates and one or more low frequency resonator chambers may be stamp formed from portions of either the internal plates or the external shells. The external shells may further be configured to define high frequency tuning chambers of a selected size and shape.

Abstract: A basic new method and devices for treating flowing substances such as subdivided solids, colloids, gels, liquids and gases, under varying temperatures, pressure and velocity conditions is disclosed. The method is characterized by forming three concentric types of non-turbulent and unobstructed streams flowing essentially in one direction but differing in velocity from one another, the outermost of which is accelerated to become a surrounding jetstream flowing tangentially past reduced openings interconnecting with the other two types of streams, reducing fluid pressure in them until suction-effect at origin point results, and by final recombination of flows to produce a helically spinning accelerated vortical exiting thrust, to insure either virtually silent atmospheric gaseous discharge or energy-efficient pumping and optimally frictionless travel of liquids or flowing solids through extended conduit, for which devices are supplied by this invention.

Abstract: A silencer comprising a cylindrical casing assembled from two half-cylindrical shell members is produced by placing in one of the shell members a row of modular channel blocks and then completing the silencer by mounting the other shell member over the row of blocks. The modular blocks are selected from a multi store holding groups of blocks of generally uniform outer shapes, but prefabricated with mutually different inner shapes such that the different blocks, each one or each pair thereof, show specific characteristics with respect to the throttling and/or sound damping capacity, whereby effective silencers for different engines are easy and cheap to manufacture, even with the use of non-corroding materials.

Abstract: A muffler capable of suppressing the shockwave generated by an internal combustion engine forming a housing having an inlet and an outlet and a center rectifier section extending between the inlet and the outlet, the center rectifier section having a transverse cross-sectional area substantially the same as or greater than the transverse cross-sectional area of either the inlet or the outlet, and having a small dimension and a large dimension, the large dimension being several magnitudes of order greater than the small dimension.

Abstract: A muffler is provided with a pair of stamp formed internal plates and a pair of stamp formed external shells. The internal plates define inlet and outlet tubes at least portions of which are provided with arrays of perforations or louvers. One or more tuning tubes may be stamp formed in the internal plates and one or more low frequency resonator chambers may be stamp formed from portions of either the internal plates or the external shells. The external shells may further be configured to define high frequency tuning chambers of a selected size and shape.