Abstract: An exhaust gas muffler of multi-chamber construction includes an outer housing having an upper and lower half shell, an inner shell, and an inner exhaust gas duct through the exhaust gas muffler. The inner exhaust gas duct has at lease one curved outlet pipe that has a first curved section and a straight outlet end runs flush with the outer housing. The invention also covers a method for the production of the multi-chamber exhaust gas muffler.

Abstract: A tuned exhaust system for small two cylinder engines, the exhaust system including a pair of exhaust passage through which exhaust gasses pass. The exhaust passages are dimensioned to providing a tuning effect to the exhaust gasses for enhanced engine performance. The exhaust passages are not straight and elongated, but rather are sprialed, scrolled, coiled, or otherwise folded upon themselves at least twice. In this manner, the exhaust passages may be housed at least in part within a muffler having a significantly reduced overall size or profile, such that the muffler may be used in small engines.

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

Abstract: A muffler device, in one preferred embodiment, having four barriers therein. Each barrier functions to form an within which the exhaust stream can be partitioned and redirected. Eventually, the exhaust streams are once again recombined and expelled from the muffler. The partitioning and reassembly of the exhaust streams provides sound attenuation while increasing the horsepower of the engine and without resulting in any build up of unignited fuel.

Abstract: An exhaust gas muffler for an engine, the exhaust gas muffler having a body, at least one inlet for the exhaust gas from the engine on the body, a baffled chamber in the body to receive exhaust gas from the at least one exhaust gas inlet, at least one exhaust gas outlet from the baffled chamber to vent the exhaust gas from the baffled chamber, at least one fresh-air inlet on the body, a heat exchange conduit extending into the baffled chamber between the fresh air inlet and the at least one exhaust gas outlet, the heat exchange conduit being sized and shaped to permit heat exchange between the fresh air and the exhaust gas in the baffled chamber, and a fresh air outlet on the heat exchange conduit, the fresh air outlet being sized, shaped and located relative to the exhaust gas outlet to permit the fresh air to mix with exhaust gases being vented from the baffled chamber to lower an exit temperature of the exhaust gases.

Abstract: An exhaust that has two isolated baffle systems in one container. This allows the exhaust from one manifold to be muffled and exhausted independently of the other manifold's exhaust. Moreover, the muffler is the same size as existing mufflers, so that it fits into the space of the prior art mufflers. Using two independent muffler elements (baffles and outer covering cans) eliminates all of the problems discussed above and increases the engine horsepower without reducing efficiency. An outer shroud covers the two muffler elements and is also designed to act as a heat exchanger. Fresh air can be pulled through the muffler to be heated for cabin heat and for carburetor heat. The shroud has space around the muffler cans, through which the fresh air passes. Inlet and outlet ports are provided to allow hoses to be connected as needed.

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

Abstract: In the engine muffler including a first expansion chamber 12 of the exhaust gas having an exhaust gas inlet aperture 11 connecting to an exhaust gas outlet of the engine, a second expansion chamber 14 having an exhaust gas outlet aperture 13, at least one first exhaust gas purifier 15 coated wit a catalyst to purify the exhaust gas purifier provided with innumerable numbers of small holes, a wall side of said second expansion chamber 14 to which the engine is not installed is formed to a double-wall construction of walls 14a and 14b with a predetermined distance, further, the double-wall is packed with a heat insulating material to improve the purification efficiency, heat insulation and sound elimination. Heated muffler wall is decreased. It is also possible by applying a detachable construction to take out the first exhaust gas purifier outside the wall for replacement or cleaning.

Abstract: A silencer for connection to the air intake of a machine such as a turbocharger compressor. The silencer comprises a housing containing a plurality of axially spaced annular noise attenuating baffles. Each baffle has an outer circumference and an inner circumference defining a central aperture, the central apertures of each baffle collectively defining an axial outlet flow passage to an outlet aperture. The baffles define a series of axially spaced generally annular partial flow passages such that air flowing through the silencer is initially split and then merges into the axial outlet passage. Each of the annular flow passages curves radially inwards from its outer to its inner circumference in a direction towards the axial. Additionally, or alternatively, the dimensions of the annular partial flow passages vary so that the velocity of air flow through the passages is greater for passages closer to the axial outlet aperture.

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: An exhaust sound attenuation and control system combines the functions of a muffler and resonator in a single, relatively compact device. The internal components of the device may also be coated with one or more emission reduction materials to provide a catalyzing function for the exhaust gases flowing through the system. The present exhaust system provides multiple gas flow paths therethrough, with different paths producing different effects in order to reduce sound output at certain frequencies, as in a resonator, and to attenuate sound throughout a broader frequency range, as in a muffler. The cross-sectional areas of each of the various internal passages and outlet pipe are at least as great, or greater, than the cross-sectional area of the inlet pipe, thereby providing a free flow system with relatively low backpressure.

Abstract: A silencer for silencing exhaust gases includes an acoustic resonator chamber that serves as a spark arrester to trap burning carbon particles and prevent them passing to the atmosphere. The silencer has an exhaust gas inlet and an exhaust gas outlet. Exhaust gases pass from the inlet to the outlet through a first passage and into a first chamber. The first chamber communicates with an acoustic resonator chamber by means of a connecting passage. The connecting passage is positioned adjacent the first passage so that sparks in the exhaust enter the acoustic resonator chamber where they are trapped. The silencer thus avoids the need for a separate spark arrester, as required by prior art silencers.

Abstract: An exhaust gas muffler for an engine, the exhaust gas muffler having a body, at least one inlet for the exhaust gas from the engine on the body, a baffled chamber in the body to receive exhaust gas from the at least one exhaust gas inlet, at least one exhaust gas outlet from the baffled chamber to vent the exhaust gas from the baffled chamber, at least one fresh-air inlet on the body, a heat exchange conduit extending into the baffled chamber between the fresh air inlet and the at least one exhaust gas outlet, the heat exchange conduit being sized and shaped to permit heat exchange between the fresh air and the exhaust gas in the baffled chamber, and a fresh air outlet on the heat exchange conduit, the fresh air outlet being sized, shaped and located relative to the exhaust gas outlet to permit the fresh air to mix with exhaust gases being vented from the baffled chamber to lower an exit temperature of the exhaust gases.

Abstract: A cap-like valve body is fitted on an outer circumference of an end portion of a communicating pipe that provides a communication between a plurality of silencing chambers formed in a muffler main body. A compressed coil spring is mounted between a flange of the communicating pipe and a flange of the valve body. Communication holes are formed in a cylindrical portion of the valve body. When the valve body receives the pressure of the exhaust gases at a pressure receiving surface and moves along the axial direction against the biasing force of the spring, the exhaust gases within the communicating pipe flow out of the communication holes to the outside of the valve body.

Abstract: A muffler for pulsating gases, especially exhaust gases of internal combustion engines, comprises a housing into which an inlet conduit enters, from which at least on outlet conduit exits and which is divided by at least one partition wall into at least two chambers. In this muffler the flow cross section of a flow path connecting two chambers and/or of an outlet conduit can be varied by means of an adjustable closure element. An actuating element acting on the closure element is provided in the region of the exit cross section of the inlet conduit.

Abstract: A muffler has an outer tube and an inner tube sealingly received in the outer tube. The inner tube has multiple shrink throats securely arranged therein and multiple through holes peripherally defined therein. Multiple baffles are formed between the outer tube and the inner tube and each of which has multiple openings. Every time when the exhaust air passes through the shrink throat in the inner tube, the speed of the exhaust air increases. Eventually, the efficiency of discharging the exhaust function increases. Due to the shrink throats, the backpressure from the exhaust air increasing, therefore hinders the power loss due to the early opening of the exhaust valve in the power (expansion) stroke.

Abstract: An exhaust processor includes a housing formed to include an interior region and a partition or first spark arrester that partitions the interior region into chambers and includes a wool filter formed to include an opening. The wool filter is positioned to filter unburned carbon particles from combustion product generated by a vehicle engine. The exhaust processor further includes an outer conduit that extends through the opening formed in the wool filter and is formed to include a passage and an inner conduit that extends into the passage and is formed to include an opening through which unburned carbon particles flow from inside the inner conduit to impinge against the outer conduit so that the outer and inner conduits operate as a second spark arrester.

Abstract: A muffler for automotive vehicles. The muffler includes a passageway, an inlet at one end of the passageway, and a single outlet or dual outlets at the passageway's other end. The portion of the muffler connected to the inlet is substantially untapered. The portion of the passageway connected to the outlet or outlets tapers from wide to narrow away from the inlet and toward the outlet or outlets. This tapered geometry results in a very appreciable reduction of heat transmitted from the muffler back to the engine, increases engine performance, and produces a pleasant, deep sound while the engine is running.

Abstract: A muffler including a long outlet pipe 20 having an exhaust gas inlet pipe portion 21, a return pipe portion 22, an exhaust gas outlet pipe portion 23, and two turnaround pipes 24, 25 for connecting the three pipe portions 21, 22, 23 together in series. These pipe portions 21, 22, 23 are arranged in parallel with one another along a longitudinal direction of a shell 2, and in such a manner that longitudinal axes 21L, 22L, 23L of the pipe portions are positioned at respective vertices of a triangle.

Abstract: A controllable muffler system is sued for use with an engine that produces a power by burning fuel. The system comprises a first passage section extending from the engine for having an exhaust gas of the engine flow therethrough. The first passage section has a catalytic converter mounted thereon. The system further comprises a dual passage section including second and third passage sections which extend separately from an end of the first passage section. The second passage has a control valve for controlling the flow rate of the exhaust gas flowing therethrough. The system further comprises a fourth passage section extending from respective ends of the second and third passage sections to the open air. The fourth passage section has a rear muffler mounted thereon. The system further comprises a control unit which controls the control valve of the second passage section in accordance with an operation condition of the engine.

Abstract: A valve for a control muffler includes: a valve element which is swingably journaled on a support shaft 5 supported by shaft holes 41a of a pair of first shaft supporting portions 41 inside the support shaft 5; bushes 6 which are respectively interposed between the support shaft 5 and a pair of second shaft supporting portions 33 that are disposed on the valve element to pivotally support the support shaft 5; and a coil spring which urges the valve element in a valve closing direction. In the valve, a welding rising portion 41b which protrudes in the axial direction is disposed on an outer opening edge of the shaft hole 41a of each of the pair of first shaft supporting portions 41, and the support shaft 5 is welded to tip ends of the welding rising portion 41b.

Abstract: A muffler for automotive vehicles. The muffler includes a passageway, an inlet at one end of the passageway, and a single outlet or dual outlets at the passageway's other end. The portion of the muffler connected to the inlet is substantially untapered. The portion of the passageway connected to the outlet or outlets tapers from wide to narrow away from the inlet and toward the outlet or outlets. This tapered geometry results in a very appreciable reduction of heat transmitted from the muffler back to the engine, increases engine performance, and produces a pleasant, deep sound while the engine is running.

Abstract: A time warp method of reducing noise in an exhaust stream includes the step of directing the exhaust stream into an inlet aperture of a sound cancellation chamber. The method also includes reflecting sound in the sound cancellation chamber toward the inlet aperture of the sound cancellation chamber. Another step of the method includes spreading the exhaust stream radially toward a periphery of the sound cancellation chamber. Yet another step of the method includes collecting exhaust from the periphery of the sound cancellation chamber in an outlet collector ring. Moreover, the method includes directing the exhaust collected from the periphery of the sound cancellation chamber substantially circumferentially about the sound cancellation chamber toward an outlet aperture of the outlet collector ring. Muffler devices for implementing the method are also disclosed.

Abstract: A cap-like valve body 37 is fitted on an outer circumference of an end portion of a communicating pipe 35 that provides a communication between a plurality of silencing chambers formed in a muffler main-body. A compressed coil spring 39 is mounted between a flange 35b of the communicating pipe 35 and a flange 37d of the valve body 37. Communication holes 38 are formed in a cylindrical portion 37a of the valve body 37. When the valve body 37 receives the pressure of the exhaust gases at a pressure receiving surface 37b and moves along the axial direction against the biasing force of the spring 39, the exhaust gases within the communicating pipe 35 flow out of the communication holes 38 to the outside of the valve body 37.

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: An acoustical silencer (10) includes a housing (12) extending generally axially vertically upwardly from an inlet (14) to an outlet (16). A laterally extending upper divider wall (18) is attached to the housing and has a plurality of apertures (22) therethrough. A plurality of tubes (24, 34) extend axially vertically through respective apertures and have an integral bulge (26) crimped radially outwardly to a larger radius than the aperture and engaging the topside of the upper divider wall to suspend the tube therefrom. A laterally extending lower divider wall (28) has a plurality of apertures (30) therethrough. The tubes extend axially vertically through the apertures of the lower divider wall and some have integral bulges (32) crimped radially outwardly to a larger radius than the aperture of the lower divider wall and engage the underside of the lower divider wall to suspend the latter from the tubes.

Abstract: An exhaust muffler includes a housing having a rectangularly shaped hollow interior without fiberglass or other packing. An inlet tube and a first outlet tube extend through one side wall of the housing, and a second outlet tube extends through an opposite side wall. The inlet tube extends to an inner end disposed at a central region of the interior in a position facing away from a forward end wall of the housing toward an opposite rearward end wall, while a baffle assembly within the interior includes perforated partitions that define two Helmholtz chambers, as well as a first passageway from the inner end of the inlet tube to the first outlet tube and a second passageway from the inner end of the inlet tube to the second outlet tube. The baffle assembly includes first and second plates disposed within the first and second passageways to split the flow of exhaust gases.

Abstract: Noise attenuator apparatus for use on a noise source including an exhaust inlet assembly using sound attenuators being equal to the exhaust pressure needs of the noise source whereby the sum total area of all smaller openings of the attenuators is equal to the exhaust volume needs of the noise source. Surrounding the inner or primary assembly, a sealed partition of any dimension containing an inner chamber which allows for the release of exhaust gas through any number of attenuators of which the smallest exit openings are equal to the exhaust volume needs of a noise source divided by the actual number of sound attenuators. The preceding assembly contained within this secondary chamber being contained or shrouded by an outer casing made from any number of plates or curved pieces whereby the primary and secondary chambers being contained by an outer casing through which the exhaust gas exits by way of measured openings or attenuators.

Abstract: An exhaust muffler includes a housing having a rectangularly shaped interior without fiberglass or other packing, an inlet tube on a first end portion of the housing for conveying exhaust gases to the interior, an outlet tube on an opposite second end portion of the housing for conveying the exhaust gases from the interior, and a baffle assembly within the interior for defining multiple different paths for exhaust gases to follow and two Helmholtz chambers for the exhaust gases to encounter as the exhaust gases flow through the interior of the housing from the inlet tube to the outlet tube. A central chamber flow path is provided that inhibits reverse flow.

Abstract: A sound attenuating apparatus and method for forming the same including stacking selectively sized sheets of sound attenuating materials and fastening the same to form elongated, perforated sound attenuating flow-through passages which are structurally connected by means of mechanical joinders outside the noise bearing fluid stream to be attenuated.

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: A muffler is described which is traversed by a fluid. Housing (1) contains sound-absorbent built-in components. The sound-absorbent components contain corrugated sheets (11, 12) instead of fibrous materials. (FIG. 3).

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 gas blow-off noise attenuator comprising two or more perforate diffusion members through which gas is arranged to pass in succession wherein the total free area of perforation in each member increases in successive stages to ensure that sonic fluid velocity occurs through one of the stages and at any mass flow within a predetermined range from a low value up to the maximum mass flow through the unit, and wherein the pressure ratio across the final diffusion member is near but above the minimum necessary to cause sonic fluid velocity through its perforations.

Abstract: For the purpose of muffling low-frequency sound waves such as occur in components of fluid-flow engines, the muffler proposed here consists of a feed pipe (1) through which (3) and around which (4) a medium flows. At its end in the direction of flow, the feed pipe (1) has a row of muffling bore holes (2) distributed over the periphery, via which the medium (4) flowing around the feed pipe (1) flows into the interior of the feed pipe (1). The effective length L of the feed pipe (1), the cross-sectional area A of the feed pipe (1) and the total cross-sectional area B of the muffling bore holes form the geometric parameters for calculating an optimum muffling of the low-frequency sound waves.

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: An exhaust silencer for internal combustion engines, particularly as used on motor vehicles including tractors. A front pipe, a plurality of core tubes and a tail pipe have successive inner flow channels of equal section areas. The plurality of core tubes are integrally connected to the larger end of a trumpet pipe. The walls of the core tubes are punched with flanged holes forming converging passages. Flow-dividing plates are provided in the tail pipe. The exhaust flow divides into smaller substreams on passing through the front pipe and the core tubes, thus raising the ratio of expansion, leading to a decrease in noise level and exhaust back pressure, while reducing engine output loss. The noise level of a vehicle can be reduced to 80-83 dB(A), while oil consumption is reduced by 6-8.8%.

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 device of a motorcycle including a muffler body for silencing the noise of exhausts of an engine located below the engine and connected to exhaust pipes which in turn are each connected to one of cylinders of the engine. Discharge pipes are connected to the muffler body to discharge the exhausts from the muffler body rearwardly of a motorcycle body.

Abstract: Resonator type mufflers of this invention utilize multiple chambers with inductor tubes between the chambers, and specific size and spatial relationships among the tubes and chambers. In one form of muffler suitable for industrial applications or vehicular use, elongated inductor tubes passing from one chamber to a second chamber have downstream ends spaced about 3/4 inch from the end wall of the second chamber, which has a central opening with area at least as large as the combined areas of the inductor tubes. For industrial mufflers which are required to be short, there is only one set of coextensively positioned inductor tubes, but for longer mufflers as on motorcycles, an elongated primary inductor preferably is used in addition, as a primary resonator stage.

Abstract: Methods and apparatus for attenuating sound levels characterized by a muffler utilizing the splitting of exhaust gas flows followed by recombining of these split flows in mutually opposed relationship. Sequentially alternating expansion and contraction of the exhaust gas is caused to occur, during which increments of exhaust gas exit sequentially along the exhaust gas flow from the muffler.

Abstract: A silencer for exhaust gases from combustion engines comprises a perforated pipe (1) provided with an inlet (2) and an outlet (3). Arranged in the interior of the pipe (1) are intermediate walls (12,13,14) provided with through-flow openings (15,16). Extending co-axially around the pipe (1) in spaced relationship therewith is a shell, and the space located between the shell and the pipe (1) is divided into a plurality of damping chambers (7,8,9) by means of partitions (10,11). Exhaust gases partly flow axially through the pipe (1) and partly from the pipe to the damping chambers and from there back into the pipe, where they mix with the axially flowing exhaust gases.

Abstract: An exhaust silencer especially for turbo-charged diesel locomotives with a single exhaust outlet combines a straight through exhaust duct preferably diverging to recover velocity pressure and minimize back pressure with dual silencing means including a large expansion tank around the duct tuned to attenuate a fundamental low frequency exhaust noise peak and smaller reactive chambered means in the duct sized to attenuate a selected mid range of higher frequency exhaust noise. Various features are included.

Abstract: A tail cap of a silencer for a motorcycle which is so constructed that a plurality of kinds of tail cap, each having different shape and construction, are provided, which is interchangeably mounted and dismounted to and from the tail part of the silencer so as to change the outer appearance and design of the silencer.

Abstract: A sound suppression system having a sound suppression chamber formed from a longitudinally extending tubular housing. One end of the tubular housing is closed by an end plug which has a bore through which passes one end of a tubular member. The tubular member comprises a gun barrel having a cylindrical sleeve surrounding a predetermined length of the gun barrel. The tubular member has a plurality of tubular passages each of which have their one end in communication with the bore of the gun barrel and their other end longitudinally displaced therefrom adjacent the end of the gun barrel to place them in communication with the interior of the sound suppression chamber. A baffle having a cylindrical body approximating the interior diameter of the tubular housing is positioned within the tubular housing. Both the interior of the tubular housing and the outer cylindrical housing of the baffle are threaded so that the baffle may be adjustably positioned through the length of the tubular housing.

Abstract: A muffler for combustion engines in which a housing is subdivided by means of bottoms into at least two successively arranged reflection chambers. Into the first inlet-side reflection chamber an exhaust entry pipe extends. An intermediate channel extends through at least one of inner bottoms from the first into at least one reflection chamber. An exhaust outlet pipe extends from the last reflection chamber out of the muffler, and has at least, in the region of the last reflection chamber, at least one inlet opening. The intermediate channel is arranged in the form of a plurality of intermediate channels which are flowed-through in one and the same direction, and each channel has a small cross-sectional area in relation to the cross-section of the exhaust inlet pipe.

Abstract: The noise damping device for piston motors in aircrafts, which allows the simultaneous cooling of the exhaust gases, offers a square cross section and a variable configuration according to the direction of the exhaust. The exterior sheets (3,4) converge towards the exhausts direction into a slot-like output aperture (7), while the lateral sheets (5,6) diverge in the same direction so that the profile of the exterior sheets diverges and that of the lateral sheets converges. Perforated sheets (8,9) are placed in parallel to and at a distance from the internal surfaces of the exterior converging sheets (3,4) and comprise edges (8a, 9a) forming cooling chambers (10,11) which are open towards the outlet aperture (7). The diverging lateral sheets (5,6) can also be fitted with holes which open into lateral supplementary cooling chambers, which chambers are open towards the side of the outlet aperture.

Abstract: A muffler for use with machines such as pneumatic drills consists of an elastomeric housing divided into an admission chamber and a series of muffler chambers. Within the housing are an inlet conduit communicating with the admission chamber and each muffler chamber, an exhaust conduit communicating with each muffler chamber as well as with a tail pipe outside the housing, and a Helmholtz resonator communicating with the admission chamber.