Abstract: An apparatus for modifying an exhaust stream of a diesel engine is provided. The apparatus includes a muffler arrangement having an exhaust inlet and an exhaust outlet in construct and arrange for sound attenuation therein. The apparatus also includes a catalytic converter arrangement positioned within the muffler arrangement between the exhaust inlet and exhaust outlet. During operation, the exhaust flow is directed both through the muffler arrangement and the catalytic converter arrangement, to advantage.

Abstract: An exhaust gas muffler for an internal combustion engine is provided, especially for a portable implement. The muffler has a housing with at least two parts, an inlet for exhaust gas issuing from the engine, and an outlet for discharge of processed exhaust gas. A partition is disposed within the housing between the inlet and outlet and divides the housing into two chambers. The partition is provided with a first opening in which a catalyzer is mounted, and at least one bypass opening. The muffler also has a respective valve member for each bypass opening. Below a specified temperature the bypass opening is closed. The valve member is controlled by the temperature in the muffler in such a way that when a prescribed operating temperature is exceeded, the bypass opening is opened.

Abstract: A muffler with catalytic converter (1) in which at least one catalytic converter element (2) is located in the muffler so that an essential part of all exhaust gases (3) from the engine are forced to pass through the element (2) and be converted there into cleaned exhaust gases (4). The element is designed as an essentially self-supporting body of catalytic material, which is hollow or partly concave and has inner and outer surfaces (6, 7), e.g. the body is shaped as a circular or non-circular sleeve, or possibly even as a narrowing sleeve (8), a dome-shaped or angular bowl-shaped body (5), and the element is, either directly or via intermediary elements, mounted to a dividing part inside the muffler, such as a partition wall (10), an outlet duct (11) or an inlet duct (12), and the mounting is so arranged that at least one end surface (13, 14) is kept fixed at the same time as the element is supported at the outer surface (7) by at least one part (10, 18, 23, 24), while the inner surface is essentially free.

Abstract: Systems and apparatus for degrading and cleaning combustion products of carbon-containing fuels such as fossil fuels. The systems and apparatus utilize catalytically reactive particles that are at least partially suspended by moving gases within a reaction chamber and maintained at a temperature sufficient to cause the suspended media particles, typically silica sand, silica gel, or alumina, to become catalytically reactive in the presence of moisture. Typically, the reaction chamber is maintained at a temperature in a range from about 30° C. to about 500° C. Moisture may be provided by the waste exhaust, although additional moisture may be introduced into the reaction chamber in order to maintain reactivity of the catalytically reactive particles. The systems and apparatus can be adapted to be used in combination with diesel engines or other internal combustion engines and industrial burners. The exhaust gases containing the incomplete combustion products can be further pressurized as needed.

Abstract: Systems and apparatus for muffling sounds produced by an internal combustion engine, and optionally catalytically degrading pollutants within waste exhaust gases. The systems and apparatus utilize a bed of particles within a muffling chamber. The gases are introduced using a diffusion tube with holes therethrough. The muffling particles preferably include silica or alumina, which can also catalytically degrade pollutants. Typically, the muffling/reaction chamber is maintained at a temperature in a range from about 50° C. to about 500° C., which is much lower than temperatures within conventional muffling systems for diesel engines. The muffling systems operate as substantially lower back pressure compared to conventional muffling systems. The systems and apparatus can be adapted to be used in combination with diesel engines or other internal combustion engines and industrial burners.

Abstract: A catalytic converter for cleaning exhaust gas, particularly from a small engine, includes a converter housing and at least one honeycomb body disposed therein and containing layers of sheet metal having catalytically active material. The converter is disposed on a dividing wall of a muffler housing for a small engine. The dividing wall has at least one opening. The housing has an upper housing component and a lower housing component. The converter housing is shaped in such a way that exhaust gas can flow successively through the honeycomb body and the opening and the converter housing is spaced apart from the muffler housing. Such a converter can be manufactured cost-effectively, can easily be integrated into existing structures and does not lead to unacceptable temperatures of the outer wall of the muffler housing during operation.

Abstract: In order to create a process for producing muffler inserts as well as novel muffler inserts, which are most optimally adaptable in size and shape to the interior space of the muffler housing to be filled, by simple means, and which also can be produced economically and have improved effect, a process is proposed for producing muffler inserts which operate entirely or partially according to the absorption principle, whereby a predetermined amount of a loose bundle of individual elements of a suitable sound-absorbing material is formed, the loose bundle is shaped roughly in an assembly shaping unit corresponding to the intended shape of the muffler insert, and whereby the loose bundle is fixed into a shaped composite in the shape corresponding to the assembly shaping unit, in such a way that the fixed shape can be handled without individual elements loosening until assembly for the specified uses of the muffler insert; however during the specific use as a muffler insert the fixing is at least partially released

Abstract: A muffler for quieting exhaust expelled from a pneumatic hand tool having a handle and an exhaust passage. The muffler includes an inner tube having a plurality of holes, a number of dividers fixedly and spacedly positioned about the inner tube, and an end cap attachable to the handle for closing off the exhaust passage. At least one of the end cap and the handle including an exit opening. The inner tube has distal and proximal ends and an exterior surface. A cutoff wall is located below at least one airflow opening. The cutoff wall forces exhaust air to exit the inner tube via the at least one airflow opening thereabove. Each divider extends outward from the inner tube exterior surface a distance less than the width of the main section. The combination of the inner tube and dividers are located within the main section.

Abstract: A muffler for attenuating noise produced by a pneumatic device having limited clearance. The muffler includes a housing, a base and an acoustic absorption insert. The housing defines an upstream end and a downstream end, with the downstream end being closed. Further, the housing tapers from a maximum width of less than approximately 1.5 inches (38 mm) to the downstream end. The base is secured to the housing at the upstream end and includes a tube for directing airflow and sound waves into the housing. Finally, the acoustic absorption insert is disposed within the housing and includes a web of fibers configured to absorb sound waves. The muffler can be utilized with a pneumatic valve having limited space available for receiving the muffler, providing noise attenuation with minimal back pressure.

Abstract: A silencer for reducing acoustic energy in an exhaust stream of gases from a combustion type source, particularly turbo-generators. In a preferred embodiment, the silencer includes an outer housing having at least one outlet opening and an inner housing provided at least partially within the outer housing. The inner housing has at least one inlet opening for receiving the exhaust stream along a flow axis and the inlet opening is in fluid communication with the outlet opening. The inner housing further includes an acoustic energy interface surface having acoustic absorbing elements oriented in a substantially non-normal direction to the flow axis. Sound absorbing material is preferably contained between the outer housing and the inner housing. In this way, the gas flow is effectively separated from the acoustic energy without significantly increasing the back pressure or resistance to flow of the exhaust stream.

Abstract: The invention concerns an exhaust silencer arrangement with a transverse exhaust silencer in a four-chamber type of construction, in particular for very small passenger-transporting motor vehicles, with a 3-cylinder rear-mounted engine and an exhaust gas turbocharger. The silencer comprises a housing which is composed of two half shells and accommodates a catalyst module in an integrated manner. The catalyst module, which does not have its own housing, forms a silencer system partition which divides the silencer into a 3-pot main chamber and an additional chamber which is in particular a resonator chamber and communicates with the main chamber via connection ducts formed in the half-shell housing.

Abstract: Muffler with catalytic converter (1) essentially arranged in direct connection with a combustion engine's exhaust port and especially intended for portable working tools such as chain saws. At least one partition (2) is embodied in the muffler, or instance in the form of a baffle (3), and the partition (2) comprises one or several apertures (9, 10), through which the exhaust flow passes in order to flow from one side of the partition to the other side, and the partition is at least partly coated with a catalyzing layer.

Abstract: Silencer for gas discharge device employing easily replaceable cartridge utilizing juxtapositioned layers of wire mesh and porous resilient material which dissipate the energy stored in an exhaust system and deflect under pressure of the exhaust gases to provide a self cleaning function and a cylindrical liner mounted within the cartridge comprising the same or larger wire mesh and wire diameter size than used in the cartridge for capturing the large particles of the exhaust gases before they pass through the layers of wire mesh forming the cartridge.

Abstract: A muffler for attenuating noise produced by a pneumatic device having limited clearance. The muffler includes a housing and an acoustic barrier material. The housing includes an inlet and an outlet. In one preferred embodiment, at least a portion of the housing is frusto-conical such that the outlet has a width greater than a diameter of the inlet. Further, the housing preferably has a maximum width less than approximately 1.5 inches (38 mm). The acoustic barrier material is disposed within the housing and is forms a plurality of microbubbles. Further, the acoustic barrier material is configured to conform to a shape of the housing. The muffler can be utilized with a pneumatic valve having limited space available for receiving the muffler, providing significant noise reduction with minimal back pressure.

Abstract: An exhaust conditioning device, comprising a housing having an entrance duct, an exit duct, and a hollow interior defined within the housing between the entrance duct and the exit duct; a conical baffle carried coaxially within the housing downstream of the entrance duct and configured to form a generally outwardly extending compression chamber therebetween; and a frustoconical baffle carried coaxially within the housing downstream of the conical baffle and upstream of the exit duct and configured to form a generally inwardly extending compression chamber; wherein the conical baffle cooperates with the housing to form a conical vacuum chamber and the frustoconical baffle cooperates with the housing to form a substantially annular vacuum chamber, downstream of the conical vacuum chamber. In one form, the exhaust conditioning device comprises an exhaust muffler. Additionally, a method is disclosed.

Abstract: The present invention is a noise reduction apparatus for use in the exhaust system of an internal combustion engine which absorbs acoustical energy from the pressurized exhaust gases while minimizing restrictions on the exhaust gases as they flow therethrough. The relatively unrestricted exhaust gas flow provided by the present invention significantly reduces the build up of back pressure and the associated drop in power and performance of the engine. At the same time, by absorbing acoustical energy from the exhaust gases, the noise level of the exhaust system is reduced. The present noise reduction apparatus includes a housing operatively adapted for being disposed in the exhaust system of an internal combustion engine, and a plurality of sound absorbing layers disposed inside the housing. Each layer is operatively adapted to allow exhaust gases to flow therethrough while absorbing acoustical energy from exhaust gases coming in contact with the layer.

Abstract: A muffler (30) for quieting exhaust expelled from a pneumatic hand tool (10) having a handle (12), an air intake port, and an exhaust port. The muffler (30) includes an inner tube with a plurality of holes, a number of washers (36) positioned longitudinally about the inner tube (32) at the location of the plurality of holes, and a flexible outer sleeve (34) positioned about the combination of washers (36) and inner tube (32). The inner tube includes a proximal end adapted to connect to the pneumatic hand tool exhaust port. During use, exhaust air pass from the hand tool (10) out the exhaust port, into the inner tube, out the inner tube holes, into the washers, through the washers, and out the flexible outer sleeve.

Abstract: A muffler (30) for quieting exhaust expelled from a pneumatic hand tool (10) having a handle (12), an air intake port, and an exhaust port. The muffler (30) includes an inner tube with a plurality of holes, a number of washers (36) positioned longitudinally about the inner tube (32) at the location of the plurality of holes, and an end cap for sealing off the inner tube. The inner tube is preferably formed as a spring. During use, exhaust air pass from the hand tool (10) into the inner tube, into the washers, through the washers, and out the muffler end cap. Alternative embodiments includes an outer tube.

Abstract: A sound baffle retention clip for use in a combustion driven heating apparatus. The clip allows for positive retention of a sound baffle within the heat tube of a combustion driven heating apparatus without adversely affecting system operating performance. Further the clip allows for easy and efficient installation of the sound baffle without compromising the integrity of the heat tube.

Abstract: A gas flow control element with a gas-permeable section, through which excess gas flows to the outside from an interior space (10), is to be improved such that it can be cleaned with ease and that a defined, reproducible discharge is present. To accomplish this task, the gas-permeable section comprises individual disks (5) lying one on top of another, which are provided with flow channels.

Abstract: A muffler utilizing a stackable porous disk sandwiched between a threaded mounting plate and an end cap and utilizing tie rods to assemble the stack is provided.

Abstract: A muffler structure for an internal combustion engine is disclosed which is capable of diminishing occurrence of fraying and lowering of exhaust gas cleaning performance and durability, and which enables replacement of the catalytic cloth and the like to readily be carried out. The muffler structure for an internal combustion engine comprises a muffler 10 and a catalytic assembly 30 disposed in the muffler 10, the catalytic assembly 30 including a spark arresting wire mesh 32 and a catalytic cloth 37 fitted over the spark arresting wire mesh 32, the catalytic cloth 37 has its peripheral edge 37a covered entirely or in substantial part and retained with side walls 34, 34, 36 peripherally provided on the spark arresting wire mesh 32.

Abstract: A brake booster includes a valve housing, an input rod movably mounted in the valve housing, a main filter, a noise absorbing member, a spring seat, a return spring for biasing the input rod, and a noise shielding member. The main filter, the noise absorbing member, the spring seat, the noise shielding member are fixed on the input rod and move integrally with the latter. The noise shielding member spaced apart from the noise absorbing member reduces the air suction noise.

Abstract: A device for deadening sound in pipelines comprising a chamber (1) positioned on the pipeline (2, 7) with a discontinuous pipeline section (3) projecting inwards at the chamber inlet and a discontinuous section (7) of the pipeline connected at the chamber outlet. Disposed within the chamber (1) opposite the opening of the pipeline section (3) there is a cover cap (4), in the form of a pipe resonator, whose side wall encloses the pipeline section (3) on one part of its length so that an annular channel (5) remains between the side wall and the pipe section (3). This permits the attainment of a very efficient sound deadening under certain geometric conditions.

Abstract: The present invention is a noise reduction apparatus for use in the exhaust system of an internal combustion engine which absorbs acoustical energy from the pressurized exhaust gases while minimizing restrictions on the exhaust gases as they flow therethrough. The relatively unrestricted exhaust gas flow provided by the present invention significantly reduces the build up of back pressure and the associated drop in power and performance of the engine. At the same time, by absorbing acoustical energy from the exhaust gases, the noise level of the exhaust system is reduced. The present noise reduction apparatus includes a housing operatively adapted for being disposed in the exhaust system of an internal combustion engine, and a plurality of generally concentric and radially spaced tubular sections disposed inside of the housing. Each tubular section is adapted with a porous wall which allows exhaust gases to flow therethrough. A plurality of sound absorbing layers are also disposed inside the housing.

Abstract: An exhaust muffler structure of an internal combustion engine in which a catalyzer is readily and easily mounted and removed to carry out the assembling work of the muffler and the maintenance work such as cleaning and replacing the parts of the muffler with ease; the generation of vibration and noise are to be prevented; and the purification capacity and durability of the catalyzer are to be improved. The exhaust muffler structure comprising: an exhaust muffler having inner and outer exhaust muffler halves which are detachably combined with each other; a communication hole formed on the exhaust muffler for guiding exhaust gas from an internal combustion engine to the exhaust muffler; a cylindrical member having a catalyzer between resilient supporting nets, characterized in that the cylindrical member is disposed in a space in the exhaust muffler with a body of the cylindrical member being supported between the both inner and outer exhaust muffler halves.

Abstract: A polymeric muffler including two halves each with baffle walls and gas flow openings integrally molded therein. The gas flow openings do not intersect with the mating edges of the baffle walls. The muffler halves are joined along the mating edges of the baffle walls and the outer walls of the two muffler halves. In a preferred embodiment, the muffler includes a filter detachably mounted on the muffler for converting exhaust gases into less toxic products. The gas flow openings are positioned to force all exhaust gas to pass through the filter.

Abstract: A catalyzer-containing muffler for treating exhaust gas from an engine is disclosed. The muffler includes an outer casing defining a closed space therein and having an inlet pipe and an outlet pipe for introducing and discharging the exhaust gas into and out of the outer casing, respectively. At least one partition wall is provided so as to divide the closed space of the outer casing into two or more spaces. At least one penetration pipe is provided through each of the partition walls for placing the divided spaces in communication with each other, and a catalyzer is provided inside at least one of the penetrating pipes. Exhaust gas noise is thus reduced and at the same time toxic substances such as NO.sub.x or SO.sub.x are removed by the muffler by a single structure.

Abstract: The invention relates to a sound-damping arrangement in a passageway system or pipe system for flowing gases, in particular in an exhaust system for internal combustion engines. The arrangement comprising at least one pipe which communicates with at least two chambers or openings, for example in a form of a muffler and/or a passageway/pipe-outlet, in such a manner that multiples of standing waves can arise in the pipe between both the chambers or openings. At least one tube is arranged in the pipe, with one end of the tube serving as in inlet while the other end of the tube is totally or partially closed. The inlet of the tube is arranged in, or in the vicinity of, one of the maximum sound-pressure regions of the pipe so as to dampen at least one maximum sound pressure.

Abstract: An exhaust muffler of this invention is constituted of a muffler main body having an opening, a muffler cover closing this opening of said muffler main body and being capable of attachment and removal, a partition separating said muffler main body and said muffler cover, and a long exhaust extension pass formed by combination of said partition and said muffler cover and extending by meandering in said muffler cover. On said partition, a communicating hole is provided to communicate between said muffler main body side and said muffler cover side. A catalyst is provided on the surface of said partition facing said muffler main body to purify exhaust gas. Thus, exhaust gas introduced into said muffler main body flows into the space formed by said muffler cover through said communicating hole after purified by said catalyst. This exhaust gas passes meandering through said exhaust extension pass during which exhaust gas is sufficiently cooled down and then discharged into atmosphere.

Abstract: This invention relates to a detachable filter and muffler device used in an exhaust system, wherein the filter and muffler device is easily detachable so that the maintenance of the exhaust system is simplified, and the cost of maintenance is reduced.

Abstract: An apparatus for modifying an exhaust stream of a diesel engine is provided. The apparatus includes a muffler arrangement having an exhaust inlet and an exhaust outlet in construct and arrange for sound attenuation therein. The apparatus also includes a catalytic converter arrangement positioned within the muffler arrangement. During operation, the exhaust flow is directed both through the muffler arrangement and the catalytic converter arrangement, to advantage.

Abstract: A muffler, especially for an internal combustion engine of a chain saw, comprises a primary and a secondary chamber through which exhaust gases from the engine in turn flow. The primary chamber (10) is formed by an inner, generally spherical receptacle (11) which is surrounded by an outer receptacle (12), and the secondary chamber (13) is formed by the space between the receptacles. The dimensions of the receptacles are such that the volumes of the chambers are generally equal.

Abstract: An apparatus for reducing the noise of coughs and sneezes by placement over the nose and mouth of the user. The apparatus has a core with a recessed portion to fit over the mouth and nose of the user and the core is made of a noise reducing material. A cover surrounds the core and has a section of absorbent material positioned over the recessed portion of the core. The noise reducing material of the core is a foamed resin. Vent holes are provided on the cover to allow the air forced into the core to exit the core and for the removal of moisture. A strap is attached to the cover to allow the user to wear the apparatus about the user's person until upon need, the apparatus is placed over the mouth and nose to reduce the noise of a cough or sneeze.

Abstract: A muffler for internal combustion engines is formed of vertically separable body sections so that the sound absorbing and filter members may be accessed easily for replacement and/or cleaning.

Abstract: An apparatus for purifying air which may act downstream supplement to a catalytic converter of an internal combustion engine for further reducing the hydrocarbon and carbon monoxide gases which the catalytic converter failed to remove. The apparatus comprises a housing filled with volcanic ash over which is directed a turbulent stream of exhaust gases for chemical reaction with the volcanic ash.

Abstract: A sound absorbing muffler used to attenuate noise carried by the exhaust gases of an internal combustion engine includes a straight-through flow tube of constant diameter and cross-section. The muffler utilizes both reactive and dissipative components and includes two annular sound absorbing end chambers, an outer annular resonating chamber, and an inner sound absorbing means. The muffler's configuration produces effective noise attenuation, yet low backpressure.

Abstract: An apparatus for modifying an exhaust stream of a diesel engine is provided. The apparatus includes a muffler arrangement having an exhaust inlet and an exhaust outlet in construct and arrange for sound attenuation therein. The apparatus also includes a catalytic converter arrangement positioned within the muffler arrangement between the exhaust inlet and exhaust outlet. During operation, the exhaust flow is directed both through the muffler arrangement and the catalytic converter arrangement, to advantage.

Abstract: A combination muffler and catalytic converter for an exhaust system of a small internal combustion engine. The catalytic converter is mounted within a chamber formed inside the muffler which functions not only to contain the catalytic converter but also to provide sound attenuation. The combination muffler/catalytic converter also includes an assembly for introducing secondary air into the interior of the muffler body containing the catalytic converter so that harmful uncombusted components such as hydrocarbons, carbon monoxide and nitrous oxides contained in the exhaust gases are further combusted prior to exiting the muffler. The secondary air supply assembly includes an opening formed in the muffler body which communicates between the interior of the muffler body and atmosphere, and a reed valve mounted directly on the muffler body adjacent this opening.

Abstract: A sound reduction unit for a compressor, in which the compressor has a cooling fan and an air intake, and the sound reduction unit includes a housing forming an enclosure about the air inlet and a plurality of sound absorbing baffles disposed in the housing and blocking any direct passage of air into the air inlet. The baffles provide free flow of air, which may be achieved by staggering the baffles in overlapping angular rows in a generally rectangular housing, but which preferably includes allowing a gap between the noise reduction unit and the cooling fan, with a flange baffle extending from the noise reduction unit beyond the cooling fan.

Abstract: A muffler is provided for sound dampening of wet exhaust gases. The muffler comprises a canister, or housing, having an inlet and an outlet. The housing is preferably constructed of a plurality of resealable interlocking sections which can be disengaged from one another to allow opening and closing of the housing to permit exposure of the sound dampening element(s) for inspection and replacement thereof or to allow for removal, servicing and replacement of the sound dampening element(s) which are positioned therein. The sound dampening element(s) can be formed from a foamed, heat resistant moldable material, such as a closed-cell concrete.

Abstract: A vertical exhaust system for an internal combustion engine that incorporates a provision for receiving and trapping water, such as rain, that may enter the open upper end of the exhaust conduit. The exhaust system includes a vertical outer body and a perforated tube is disposed within the outer body and spaced therefrom to provide an annular chamber therebetween. A plug or closure is secured within the tube and is spaced from the lower end of the tube, thus closing off the tube. An annular flange interconnects the inner tube with the outer body and is spaced longitudinally below the plug, to thereby enclose the lower end of the chamber. A drain hole extends through the outer body and connects the chamber with the exterior. The drain hole is spaced above the flange, so that the space between the flange and the drain hole comprises a trap to collect water that may enter the upper end of the exhaust system.

Abstract: A central air conditioning unit with a blower and feed duct is provided with a filter unit between the blower and the air outlet into the space applied with the conditioned air. The filter unit has both a sorption filter and a suspended filter and is constructed and arranged to form a sound barrier, i.e. a sound-damping or sound-blocking system.

Abstract: A car silencer includes an outer pipe having a front expansion chamber defined in a front portion of the outer pipe connected with a connecting tube which is connected to an engine manifold for directing waste gas as discharged from a car engine, an inner pipe detachably inserted in a rear expansion chamber in the outer pipe at a rear portion of the front expansion chamber, an absorbing and filtering medium filled in the inner pipe, and a perforated tail pipe inserted in the absorbing and filtering medium, wherein an engine exhaust gas will be reduced its sound in the front and rear expansion chambers and a plurality of pollutants laden in the exhaust gas will be absorbed, filtered and removed in the absorbing and filtering medium for preventing air pollution caused by an engine waste gas.

Abstract: An exhaust collector for use with an internal combustion engine of the type having a plurality of generally nested exhaust tubes for individually receiving exhaust gases from separate associated engine exhaust ports. The collector is frustoconically shaped and has an open upstream end sealingly engaged with the downstream ends of the exhaust tubes to receive exhaust gases directly therefrom. The collector is oriented with its generally conical shape convergent in the downstream direction, and includes an internal cone shaped stem piece oriented with its longitudinal axis coaxial of the collector. A base portion of the stem piece is nested between and extends from the downstream ends of the exhaust tubes, and an apex end of the stem piece is generally aligned with the collector downstream end. The collector interior wall defines a smooth cylindrical surface when taken in radial cross section at any position along generally the entire length of the axis of the collector downstream of the tube exit ends.

Abstract: A sound muffling device for use in lawnmowers includes a hollow body containing an aperture plate, a plurality of serpentine configured pipes, a plurality of fans, a double net having a bundle of wires, and a microporous plate, an adaptor having a sound inlet disposed on the exterior of the front end of the hollow body, and a sound outlet of the exterior of a rear end of the hollow body.

Abstract: The silencer includes a tubular envelope supported by an end piece for fixture to a gas supply source in which the pressure is to be reduced. A perforated plate and a disk close off the ends of the envelope which is drilled with escape apertures in the region of the disk. According to the invention, the gas flows at sonic speed through the plate to enter the envelope which is completely filled with a packing consisting of a tightly wound roll of wire mesh. The packing absorbs the shock waves developed by the supersonic flow of the gas in the packing. The latter maintains a subsonic flow with a low noise level upstream of the silencer. Application to the treatment of a surface by blasting of a gas flow is also described.

Abstract: An intake muffler, which is particularly intended for use in two-stroke-cycle internal combustion engines, comprises a stiff housing, in which a partition defines two chambers. An inlet tube extends into the larger first chambr. At least two communicating tubes extend through the partiton. The second chamber communicates with a tubular outlet port. In order to ensure an effective damping of sound even in conjunction with a high engine power, the inlet tube consists of a diffuser, which is divided into two or more passages, and the tubes through which the two chambers communicate with each other differ in diameter and/or in length.

Abstract: An exhaust gas cleaning device is disposed within an exhaust pipe connected to the exhaust port of an internal combustion engine. The exhaust gas cleaning device comprises an inner pipe disposed coaxially within the exhaust pipe with an annular space defined therebetween, the inner pipe being provided with a plurality of perforations, and laminated structures disposed upon the inner and outer surfaces of the inner pipe and including a catalyst for cleaning unburned components of the exhaust gas flowing within the exhaust pipe, each of the laminated structures being formed of a material which is not deleterious to the catalyst. The laminated structure includes a catalyst carrier layer formed by, in accordance with one method, fusibly injecting a catalyst including a solution onto an intermediate layer formed upon the inner and outer surfaces of the inner pipe and drying the same so as to remove the liquid component therefrom.

Abstract: An automobile for racing comprises a body, an engine, wheels, a fuel system, an exhaust system and wings having an adjustable angle of attack arranged so as to provide an upwardly directed force in the rear part of the automobile for racing and to create a turning moment relative to the front wheel axle in order to increase the maximum speed during racing by reducing friction of the automobile. Wings are arranged so as to create a turning moment relative to the front wheel axle and to lift the automobile or to provide aerodynamic braking by a remote control system. The wings are adapted to provide maneuvering of the automobile by aerodynamic braking separately of each wing. A fuel system of the automobile comprises a device for energizing the air-fuel mixture adapted to reduce the consumption of fuel. The automobile for racing comprises a tire inflation detection system adapted to inform an occupant of the automobile when the inflation pressure of any tire is reduced.