Abstract: A chromed exhaust pipe and muffler for motorcycles that is capable of withstanding the extreme heat generated at high rpm's of a motorcycle engine without discoloring or “bluing”. A double wall construction is utilized for the exhaust pipe and muffler with the back side of the exterior chromed pipe cut away along the length of the pipe from the mounting flange to the muffler core. The cut-away exterior pipe is dimensional to allow the interior pipe to be inserted—one piece from the mounting flange to the muffler core, as well as cooling the exterior pipe, thereby preventing heat discoloration of the exterior chromed pipe.

Abstract: The present invention relates to an apparatus for controlling exhaust noise in an internal combustion engine by using the length difference between the exhaust pipe and the bypass pipe. The apparatus comprises an exhaust pipe for outwardly releasing exhaust gas from the engine; a bypass pipe variable in length which diverges from said exhaust pipe with a distance and has U-shaped and reverse U-shaped sections formed alternately; an actuator having an actuating rod connected to said bypass pipe to vary the length of said bypass pipe; and a control unit for controlling said actuator. The bypass pipe has the U-shaped and reverse U-shaped sections arranged alternately so that the variable length of the bypass pipe can be extended while minimizing the space for installing the bypass pipe, and thereby noise in the low frequency band can be suitably reduced.

Abstract: A chromed exhaust pipe and muffler for motorcycles that is capable of withstanding the extreme heat generated at high rpm's of a motorcycle engine without discoloring or “bluing”. A double wall construction is utilized for the exhaust pipe and muffler with the back side of the exterior chromed pipe cut away along the length of the pipe from the mounting flange to the muffler core. The cut-away exterior pipe is dimensional to allow the interior pipe to be inserted in one piece from the mounting flange to the muffler core, as well as cooling the exterior pipe, thereby preventing heat discoloration of the exterior chromed pipe. Spacers are welded to the interior pipe and the exterior pipe at the backside cut-away of the exterior pipe to space the interior pipe within the exterior pipe. The muffler core includes a baffle core enclosed by an interior pipe section, allowing gases to flow out the back end only. The interior pipe is spaced apart from and enclosed in the exterior chromed pipe.

Abstract: A device for reducing sound emitted by the air intake of a internal combustion engine is provided. The device includes a dampening chamber formed of a one piece construction by rotational molding. Included as part of this mold are two tubular pipe-like sections designating both an inlet and an outlet whereby air is directed into the engine through the inlet and sound emitted by the engine is dampened as it enters the outlet of the silencer. The inlet and outlet are each formed within a pocket constructed in the mold that assists in creating the flow path for air as it moves throughout the chamber. The arrangement of the inlet and outlet in relation to one another assists in defining the sound reduction capability of the instant design and construction.

Abstract: The use of fiber metal or similarly high flow resistance and high acoustic transparency material as a liner for traditional acoustically absorptive media in a dissipative muffler exhibits improved low frequency sound attenuation, reduces backpressure, and eliminates media entrainment or “blow-out” phenomenon which results in longer muffler life. The same class of materials may also be used to fashion an element that provides linear occlusion inside an otherwise line-of-sight type of muffler, where the occluding element provides improved impedance-matching acoustic absorption. Disclosed embodiments providing linear occlusion minimize traditional increases in muffler backpressure by incorporating helical, conical, and annular members in mufflers with round ducts. To maximize attenuation, a muffler according to the invention may feature both a fiber metal fill liner and a fiber metal linear occlusion element.

Abstract: A muffler assembly is disclosed allowing one or more outlet tips to be secured to an exhaust. The muffler comprises a casing having an outlet end including threaded holes or threaded bolts attached to the casing, an outlet tip with a tubular member and an annular flange connected to the tubular member, wherein the flange has a plurality of holes or incisions and wherein screws or nuts cooperate with the threaded holes or threaded bolts, respectively, to secure the outlet tip to the casing.

Abstract: A chromed exhaust pipe and muffler for motorcycles that is capable of withstanding the extreme heat generated at high rpm's of a motorcycle engine without discoloring or “bluing”. A double wall construction is utilized for the exhaust pipe and muffler with the back side of the exterior chromed pipe cut away along the length of the pipe from the mounting flange to the muffler core. The cut-away exterior pipe is dimensional to allow the interior pipe to be inserted—one piece from the mounting flange to the muffler core, as well as cooling the exterior pipe, thereby preventing heat discoloration of the exterior chromed pipe. The muffler core is completely enclosed by an interior pipe section, allowing gases to flow out the back end only. The interior pipe is spaced apart from and enclosed in an exterior chromed pipe.

Abstract: A hanger with swivel arm is adapted for securing a portion of an exhaust system such as a muffler, for example, to an undercarriage of automobile. In a preferred embodiment, the hanger incorporates an arm including a proximal end and a distal end, a bushing defining an orifice, and a retaining member. Preferably, the orifice is adapted for receiving the proximal end of the arm so that the proximal end is retainable by the bushing and rotatable therein, such as through an arc of 360°. The retaining member is configured to mount to the frame member of the automobile so that the bushing is fixedly retained thereby. So provided, the arm may be secured to a portion of the exhaust system so that the exhaust system is securely retained by the undercarriage of the automobile. Methods also are provided.

Abstract: An exhaust muffler for a fuel-operated heating device has upper and lower housing half shells, an exhaust gas through-duct and absorption and reflection chambers. The exhaust muffler is connectable to an exhaust pipe of the heating device. The exhaust gas through-duct has an inlet pipe of a single absorption chamber and a single following reflection chamber that are separated by a partially perforated partition, with double reversal of the exhaust gas flow, and an outlet pipe; the inlet pipe being perforated on the outer surface side, with an S-shaped curved section and a straight end section, and the outlet pipe being a straight outlet pipe, closed on the outer surface side, and the straight section of the inlet pipe runs parallel to, and at a spacing from, an inlet section of the outlet pipe.

Abstract: Sheet having a multilayer structure, called a sandwich sheet, composed of two rolled metal skins which are joined together by a core, in which sheet the core contains a stainless steel wool.

Abstract: In a double-wall tail pipe for an exhaust pipe of a motor vehicle exhaust system comprising an inner shell to be mounted on the exhaust pipe, an outer shell surrounding the inner shell and being supported thereon in spaced relationship to form an annular air space therebetween for conducting cooling air therethrough, a support structure provided with air passages is disposed between the inner and the outer shells in an area where the inner shell is seated on the exhaust pipe when the tail pipe is mounted on the exhaust pipe which support structure interconnects the inner and outer shells in an area which is spaced from the discharge end of the tail pipe.

Abstract: A single-in/single-out exhaust muffler 20 for an internal combustion engine includes a curved inner tube (26), an exhaust inlet (24) in communication with a first leg (32) of the curved inner tube (26), and an exhaust outlet (28) in communication with a second leg (36) of the curved inner tube (26). The exhaust inlet (24) is configured to receive exhaust gas (22) and the exhaust outlet (28) is configured to output the exhaust gas (22). A curved portion (38) interconnects the first and second legs (32 and 36). A sound absorbing material (40) is wrapped around the curved inner tube (26), and a muffler housing (42) encloses the curved inner tube (26) and the sound absorbing material (40). The first leg (32) includes a perforate region (58, 60) and an imperforate region (62, 64) arranged about a circumference (66) of the first leg (32). Likewise, the second leg (36) includes a perforate region (68, 70) and an imperforate region (72, 74) arranged about a circumference (76) of the second leg (36).

Abstract: An exhaust pipe for an internal combustion engine has non-circular passages that extend from the engine exhaust port to the atmosphere. The performance of the engine is not impaired by the non-circular passages compared with prior pipes having circular passages of the same cross sectional areas at corresponding locations along the pipes. The non-circular cross section enables two or more passages to be located inside a single outer wall. Plates inside the outer wall divide the outer wall interior into the separate passages. Adjacent passages thus share a wall. The exhaust pipe includes headers that conduct exhaust gasses directly from the engine to the associated passages. In a modification of the invention, an exhaust pipe is tuned for performance at two different engine operating speeds by tuning a passage on one side of a shared wall differently than another passage on the other side of a shared wall.

Abstract: A chromed exhaust pipe and muffler for motorcycles that is capable of withstanding the extreme heat generated at high rpm's of a motorcycle engine without discoloring or “bluing”. A double wall construction is utilized for the exhaust pipe and muffler with the back side of the exterior chromed pipe cut away along the length of the pipe from the mounting flange to the muffler core. The cut-away exterior pipe is dimensional to allow the interior pipe to be inserted—one piece from the mounting flange to the muffler core, as well as cooling the exterior pipe, thereby preventing heat discoloration of the exterior chromed pipe.

Abstract: An adjustable muffler system for a combustible engine including a muffler adapted for connection with an exhaust pipe of an engine, a blocking tube configured to be removably inserted within the muffler, and latch means adapted to removably secure the blocking tube within the muffler. In other embodiments, the blocking tube can include various holes or slots and may be telescoping or fabricated from multiple pieces.

Abstract: A muffler assembly for muffling noises associated with a compressor. The muffler assembly is mounted on the compressor such that the two move as a solid body. The muffler assembly includes an intake having a hollow interior adapted to receive a first flow of gas from the ambient environment. A baffle disposed in the hollow interior of the intake restricts the flow of gas through the intake. In one embodiment, the baffle defines at least a portion of a plurality of fluid portals that separate the first flow of gas into a plurality of flows of gas as the gas passes from a first side of the baffle to a second side of the baffle. As a result, the first flow of gas is disturbed and noise from the compressor is thereby attenuated. In another embodiment, a plurality of baffles are disposed in the hollow interior of the intake to define a tortuous path for the flow of gas through the intake for attenuating noise.

Abstract: A turbine exhaust structure is provided for a vehicle which includes an exhaust tail pipe having an inner wall defining a screw hole. The turbine exhaust structure includes a turbine exhaust device secured in the inner wall of the exhaust tail pipe, and a bolt co-operating with a nut for securing the turbine exhaust device in the inner wall of the exhaust tail pipe through the screw hole. The turbine exhaust device includes a housing secured in the inner wall of the exhaust tail pipe, a wheel disk secured in the housing, a plurality of catch pieces mounted in the wheel disk, an axle base secured in a central portion of the wheel disk, an axle rod rotatably mounted in the axle base of the wheel disk and having a first end provided with a first vane wheel and a second end provided with a second vane wheel, and two bearings mounted between the axle base and the axle rod.

Abstract: A valve in an exhaust gas muffler device of a motor vehicle with exhaust gas conducting openings connecting the interior of a housing of the muffler device to outward of this housing in which one of the housing openings can be closed with a closure element situated within the housing and displaceably mounted on the housing. When the opening is closed, the closure element sealingly abuts on the edge of the opening. The displacement axis of the closure element runs perpendicularly with respect to the plane of the housing opening, and the closure element is coupled to a positioning motor.

Abstract: An improved fluid flow system for enhancing fluid flow through an opening. The first embodiment uses a first extension member for extending an opening through a perpendicular surface and a second extension member with a generally converging introductory section secured in a sealed overlapping relationship to the distal end of the first extension member. A second embodiment uses a pair of conduits of equal cross-section with a bulbous section therebetween with one of the conduits inserted into the bulbous section. A third embodiment with unequal cross-sections with the smaller diameter conduit inserted into the larger diameter conduit and sealed thereto for forming a continuous conduit.

Abstract: The invention relates to a device in a silencer unit of an automotive vehicle, for suppressing unwanted noise originating from an exhaust gas flow from the vehicle engine, said silencer unit being terminated by an end pipe, through which said exhaust gas flow is conveyed to the surroundings. The invention is characterized by the end pipe comprising at least one perforated section having a predetermined extension (L2) in the longitudinal direction of the end pipe, and being positioned downstream of a point (L3) along the end pipe where there is substantially no turbulence in the exhaust flow. Through the invention, an improved silencer unit is provided, with which predetermined requirements for comfort directed low-frequency suppression of the exhaust flow noise, as well as statutory requirements for high-frequency absorption of the noise, are fulfilled.

Abstract: A muffler for the exhaust gas of an internal combustion engine is provided. The muffler has a housing with an inlet opening and an outlet, and surrounds a muffling chamber. In the flow path of the exhaust gas a spark arrestor screen, and on the side of the inlet opening an exhaust gas diffuser, are provided. The muffling chamber is divided by a partition into a first and second partial chamber. The volume of the second partial chamber corresponds at least approximately to the volume of the first partial chamber. The spark arrestor screen is disposed in the partition.

Abstract: The device for producing an overtone-rich, sporty exhaust sound of the exhaust system of a four-cylinder engine includes exhaust pipes with four manifold pipes, at least one front pipe and a tail pipe. The length and/or cross-section of at least one exhaust pipe differ from the length and/or cross-section of the other exhaust pipes. At least some of the exhaust pipes lead into a first, second and/or third collecting point.

Abstract: Compactness is enhanced while retaining the performance, noise deadening characteristic and engine output. The ratio of the distance, a, from a gas outlet end, p, of an exhaust pipe to an inner wall of a rear partition wall to an inside diameter ∅A of the exhaust pipe is set in a relation of 0.6≦(a/∅A)<1.2, while the ratio of the distance, b, from a gas inlet end, q, of a tail pipe to an inner wall of a front partition wall to an inside diameter ∅B of the tail pipe is set in a relation of 0.4≦(b/∅B)<1.2, to afford a silencer having an optimum combination of engine output characteristic and compactness while retaining a noise deadening effect.

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: An exhaust muffler (20) for an internal combustion engine (25) includes a tapered tube (28) and an outer tube (40) axially aligned with and surrounding the tapered tube (28) so that an annular passage (42) is formed between the tapered tube (28) and the outer tube (40). The tapered tube (28) has an exhaust inlet end (30) for receiving exhaust gases (76) from the engine (25) and an exhaust outlet end (34). The outer tube (40) has an air inlet end (50) for receiving air (49) external to the engine and an air outlet end (52). The external air (49) flows in the annular passage (42) toward the air outlet end (52). The flow of the external air (49) creates a low pressure region (54) downstream of the exhaust outlet end (34) to accelerate the receipt of exhaust gases (76) from the engine, and elliptical holes (62) in the tapered tube (28) allow the smooth flow of exhaust gases (76) from tapered tube (28) to mix with the external air (49) to achieve effective noise attenuation.

Abstract: An exhaust system includes a support member mounted to a motorcycle frame. First and second exhaust systems are mounted to the support member such that the support member places the first and second exhaust systems in fluid communication with each other.

Abstract: A silencing member has a plurality of elongate members each having a plurality of elongate glass fibers, with the plurality of elongate members being cross-layered to define a fabric.

Abstract: A muffler comprises an outer shell defining a chamber, a baffle positioned in the chamber defined by the outer shell, and an inner plate positioned in the chamber. The inner plate includes a channel and a ridge coupled to the channel. The ridge extends away from the channel. The baffle includes an outer edge positioned adjacent to the outer shell and an inner edge positioned adjacent to the ridge and spaced apart from the channel.

Abstract: An exhaust pipe for an internal combustion engine has non-circular passages that extend from the engine exhaust port to the atmosphere. The performance of the engine is not impaired by the non-circular passages compared with prior pipes having circular passages of the same cross sectional areas at corresponding locations along the pipes. The non-circular cross section enables two or more passages to be located inside a single outer wall. Plates inside the outer wall divide the outer wall interior into the separate passages. Adjacent passages thus share a wall. The exhaust pipe includes headers that conduct exhaust gasses directly from the engine to the associated passages. In a modification of the invention, an exhaust pipe is tuned for performance at two different engine operating speeds by tuning a passage on one side of a shared wall differently than another passage on the other side of a shared wall.

Abstract: An exhaustion pipe structure including a hollow tube body, a fitting ring, locking plates, locking screws, an exhaustion fitting pipe and a decoration. The decoration is replaceably fitted with the hollow tube body which is fitted around the exhaustion pipe of a car so as to beautify the exhaustion pipe.

Abstract: A silencer comprising an outer sleeve made of a aluminum or an aluminum alloy, an inner sleeve made of a iron or steel, and acoustic material inserted between the outer sleeve and the inner sleeve. An end cap for closing a downstream end of the silencer comprising a first member made of iron or steel which is formed into a shape of the end cap, and a second member made of aluminum metal which is formed into the same shape as the outline of the first member, the peripheral portion of the first member and the peripheral portion of the second member being laminated. An end plate made of aluminum being mounted on an upstream end of the silencer. Clamping members made of iron or steel including female or male screws are secured to the end plate. An exhaust pipe is provided with a mounting seat at a fixed position thereof. The silencer can be secured to the mounting seat by means of the clamping members and bolts or nuts made of iron or steel. The end cap can be welded to a part of the outer sleeve.

Abstract: A modular Active Noise Control exhaust silencing system is provided including a housing defining an acoustic enclosure having an acoustic outlet port. A speaker is disposed within the acoustic enclosure and an amplifier is disposed within the housing and connected to the speaker. A microphone is associated with the housing for detecting the exhaust noise. A control unit is disposed within the housing in communication with the microphone for receiving signals therefrom. The control unit determines an anti-noise signal for the amplifier for creating an anti-noise responsive to a detected noise source. A port dish is disposed adjacent to the acoustic outlet port which serves as a noise cancellation aid.

Abstract: A tube element especially for exhaust systems and exhaust recirculation systems of combustion engines in vehicles which includes at least one helically or annularly corrugated bellows provided with cylindrical end fittings on each end of the bellows; a flexible hose made of metal and situated on an interior surface of the bellows; and a braiding hose made of metal wire which coaxially encloses an exterior surface of the bellows. The braiding hose being placed on the cylindrical end fittings together with the flexible hose so that the flexible hose and the braiding hose are connected firmly and at least indirectly. The braiding hose is installed in a state of pre-setting so that the braiding hose has a reduced radial cross-section which in frictional contact with the exterior surface of the bellows.

Abstract: In an arrangement for interconnecting two exhaust pipe sections of a motor vehicle exhaust system with a vibration dampening structure disposed between the two pipe sections, a first one of the pipe sections has a coupling member radially extending therefrom and the second pipe section has a coupling structure connected to the coupling member in a circumferentially elastic fashion so as to permit limited relative rotation between the two pipe sections.

Abstract: A first muffler (4) is connected to a rear end portion of the exhaust pipe (2) extending from a single-cylinder engine toward one side of a rear portion of the vehicle body and is provided on one side of the vehicle body. A second muffler (5) is provided on the other side of the vehicle body opposite to the first muffler (4) through a connecting pipe (6). An outer side surface near the front end portion of the first muffler (4) and the second muffler (5) are covered with first and second covers (7) and (8) both plated. Each of the exhaust pipe (2) and the first and second mufflers (4) and (5) have double-pipe structure with outside plated. Further, a front end portion of the second cover (8) is curved toward the center of the vehicle body, and a phantom line as a continuous frontward extension from the front end portion of the second cover (8) is positioned before the axis of the connecting pipe (6).

Abstract: The fan-out effect of a paper web, passing through a web-fed printing press having a plurality of printing units, is corrected by providing control assemblies before selected ones of the printing units. The control assemblies each have a number of control elements and counter control elements. The number of control and counter control elements in each assembly varies with the moisture content of the paper web passing through the web-fed printing press.

Abstract: An exhaust system for a vehicle includes a muffler connected to an exhaust pipe, which is in turn connected to an engine. A spark arrester is provided with a tail pipe and connected to the rear end of the muffler, and is capable of discharging an exhaust gas flowing through the muffler through the tail pipe of the spark arrester into the atmosphere. The interior of the muffler can be divided into a plurality of expansion chambers connected by restricting passages by attaching the spark arrester to the muffler to enhance the sound attenuating effect. The interior of the muffler is divided into the plurality of expansion chambers by separators disposed in the muffler and a spark arrester combined with the muffler.

Abstract: A small-sized muffler having porous partition walls includes a first expansion chamber, a second expansion chamber, a third expansion chamber and a fourth expansion chamber. A first porous partition wall is longitudinally arranged within the third expansion chamber so as to define a fifth expansion chamber. Similarly, a second porous partition wall is longitudinally arranged within the first expansion chamber so as to define the sixth expansion chamber. The first porous partition wall and the second porous partition wall are provided with small holes over their entire surface. The first porous partition wall and the second porous partition wall are each formed as a convexly curved surface curved toward the center of the muffler around the first feeding pipe and the second feeding pipe, respectively.

Abstract: For use with a vehicle, a combination unit includes a fluid storage chamber for storing fluids such as windshield washer fluid and an acoustic resonance chamber for attenuating vehicle air intake noises. The fluid storage container and the acoustic resonance chamber are hingedly attached and define there between an airflow cavity for housing the vehicle air filter with suitable ducting to direct ambient air through the filter and into the engine intake system.

Abstract: Air gap-insulated exhaust pipe (2) with a sliding fit (16) between two inner pipe sections (12, 14) in a middle area of the length of the exhaust pipe (2). A radial mounting (26) of the inner pipe (6) in the outer pipe (4) is provided in the area of a bend (20) or beyond the bend (20), which joins the leg (18) of the exhaust pipe (2) in which the sliding fit (16) is located. In terms of manufacturing technique, the radial mounting (26) may be prepared before or after the bending of the double-pipe arrangement. The sliding fit (16) may be prepared, even in the case of a straight exhaust pipe, manifold, or the like, by using a spacer sleeve (40) and joint calibration of the pipe ends of the inner pipe sections (12, 14), and the spacer sleeve burns off at the time the exhaust pipe is put into operation for the first time. As an alternative, the sliding fit (16) may also be prepared by polygon calibration and rotating the pipe ends by half the pitch of the polygon.

Abstract: To reduce turbulence in a fluid flow, especially exhaust gas from automotive internal combustion engines, within a flexible conduit element, a bellows (1, 40, 42) has an internal hose (6) located therein made of woven or knit metal wire. The hose is engaged against the internal corrugations of the bellows (1) and/or a connecting pipe (41) between adjacent bellows (40, 42) to guide the exhaust gases, and dampen vibrations and oscillations, which may become resonant with the corrugations of the bellows, and thereby decrease noise level during the gas flow. The hose (6) is engaged against the inner corrugations (3) of the bellows by, for example, first axially compressing the hose to result in permanent deformation of the wires to a diameter larger than the clear inner diameter of the bellows; by then forcing the hose into the bellows, the hose will resiliently compress and engage against the bellows.

Abstract: A silencer is provided for a marine diesel engine. The silencer comprises a conical silencer element (20) located within an exhaust duct (10), the silencer element having apertured surfaces which are inclined to the flow of exhaust gases in the duct.

Abstract: The present invention includes a cast in place aluminum tailspout and a stainless steel exhaust pipe. The stainless steel exhaust pipe includes a flared out portion. The cast in place tailspout includes a section that surrounds at least a portion of the flared section of the exhaust pipe and includes a hooked finger for engaging an outwardly extending shoulder of the flared portion.

Abstract: A silencer includes: a porous inner pipe provided in a peripheral wall thereof with a large number of small pores; an outer pipe surrounding the porous inner pipe; a sound absorbing material incorporated in an annular clearance between the porous inner pipe and the outer pipe; and a plurality of exhaust gas expansion chambers defined in the porous inner pipe and arranged such that an exhaust gas is sequentially passed through the exhaust gas expansion chambers. The sound absorbing material is formed of a heat-resistant fiber layer which is wound around an outer peripheral surface of the porous inner pipe with a binder interposed therebetween, and an outer peripheral surface of the heat-resistant fiber layer is press-fitted to an inner peripheral surface of the outer pipe with a predetermined interference. Thus, it is possible to prevent a reduction in sound vanish effect due to the leakage and short-circuiting of an exhaust gas and a reduction in engine power performance.

Abstract: An assembly includes an exhaust pipe unit and a muffling device. The exhaust pipe unit has at least one gas expanding section. The muffling device includes a muffler unit installed on the gas expanding section of the exhaust pipe unit. The muffler unit has an outer housing surrounding the gas expanding section of the exhaust pipe unit so as to define a gas expanding space in the outer housing, in such a manner that the gas expanding space is communicated with an interior of the exhaust pipe unit. The muffler unit includes a filtering material received within the gas expanding space of the muffler unit so as to filter exhaust gas which flows through the gas expanding space.

Abstract: The invention comprises an exhaust system for a motorcycle engine which has an outer imperforate casing having a substantially elliptical cross-section and an inner, coaxial, perforate sleeve also of elliptical cross-section which is of lesser dimensions to provide an annulus within the casing which is packed with a gas permeable material, high temperature resistant material such as fiberglass. The muffler has a single piece inlet end cap and a single piece outlet end cap. Each end cap has an elliptical flange over which is received an end of the outer casing of the muffler. The end caps also have integral mounting flanges to receive and support the inner perforate sleeve. Preferably the muffler is provided with a replaceable sound choke which is a small diameter sleeve that can be removably secured in the discharge end of the muffler, thereby permitting the muffler to be switched between restricted off-road use and unrestricted off-road use.

Abstract: A compact filter structure is provided having a cylindrical body disposed in the expansion chamber of a muffler. A tail pipe is inserted into the filter. The diameter of the filter is greater than that of the tail pipe. The filtering function of the body and the noise reducing function of the tail pipe are separated from each other. The filter structure can be formed in a compact construction which provides a large filtering capacity.

Abstract: The exhaust muffler as a tailpipe head member including a front end mounted inside an expansion chamber of the muffler. The front end of the head member deflects exhaust gas pressure waves passing through the chamber. An annular passage is provided by the space separating the front end of the head member and the expansion chamber. A flow regulating conduit communicates exhaust gas from the annular passage to an outside of the muffler. The front portion of the expansion chamber can be provided with a series of annular flange steps for mounting onto various sizes of annular flanges of exhaust manifolds. The exhaust muffler both reduces noise levels and improves performance of the engine.

Abstract: To provide a compact exhaust apparatus for allowing exhaust sounds of each cylinder to be heard. A muffler includes a tubular member the inside of which is divided into three independent expansion paths by partition plates. The partition plates extend in an axial direction. Each of the expansion paths is divided into a first expansion chamber, a second expansion chamber and a third expansion chamber by diametrical partitions. The first expansion chamber and the second expansion chamber are in communication with each other by way of a pipe while the second expansion chamber and the third expansion chamber are communicated with each other by way of a second pipe. A tail pipe is connected to each pipe to discharge exhaust gas to the outside.

Abstract: An electronically controlled active exhaust-noise attenuation muffler, comprises a loudspeaker serving as a secondary sound source arranged upstream of a tailpipe and communicating with an interior of an exhaust pipe, for attenuating a noise level of exhaust noise produced by the exhaust system by emitting a secondary sound, which is in opposite phase to the exhaust noise, into the exhaust pipe. The tailpipe is formed in a flared-out fashion so that a cross-sectional area of the tailpipe gradually increases towards a downstream end thereof, to reduce pressure loss in exhaust gas flow in the exhaust pipe by radiating the exhaust gas through the flared-out tailpipe. The tailpipe section is a high-frequency exhaust noise attenuation structure to attenuate a high-frequency noise component propagated with a moving stream of the exhaust gases.