Abstract: A combination air inlet - engine noise silencer consists of a shell-type housing of large volume having a small volume air inlet tube at one end and an outlet of restricted area at another portion at right angles to the inlet for direct passage into the engine induction system, the air inlet tube containing a conical-like insert coaxially mounted with its apex facing upstream to provide a base portion at right angles to the axis of the inlet tube whereby engine acoustical waves passing from the engine towards the inlet are reflected against the base portion of the cone back into the expansion chamber to be dissipated and broken-up thereby reducing the engine noise, the cone concurrently increasing the velocity of the air flow into the engine proper to increase operating efficiency.

Abstract: A structural improvement made in the air pump usable in either a single or a plurality of fish bowls. The diaphragms used to prevent the air from flowing in reverse are specially designed in a shape which can be inserted into the outlet of air circulating ports of the pump so as to prevent the diaphragms from slipping away and detaching from the air circulating ports, and finally losing the one-way discharge function accordingly.

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

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

Abstract: An adjustable motorcycle muffler affixable to the exhaust pipe of a motorcycle. The muffler includes a stationary ring which is affixed to the exit end of the muffler body and the stationary ring has several openings therethrough. An adjustable ring is affixed to the face of the stationary ring and is movable to increase or decrease the gas flow resistance through the stationary ring.

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

Abstract: In a tangential blower having side walls near the air outlet provided with lugs projecting into the high pressure chamber.

Abstract: An exhaust silencer for an internal combustion engine, has an inlet, a noise-attenuation chamber containing a noise-attenuation matrix, and an outlet. The noise-attenuation chamber is of rectangular cross-section, and has one transverse dimension which is substantially larger than the other transverse dimension. The noise-attenuation matrix is constituted by a plurality of flat plates made of a material which is heat resistant and corrosion resistant, the plates being placed in spaced parallel relationship.

Abstract: The present invention provides an exhaust system comprising an elongated hollow casing having an upstream muffler chamber containing an insulated removable cartridge for sound absorbing and sound collecting, an intermediate chamber containing a removable spark and moisture arrester and a downstream chamber having a removable and replaceable cartridge containing exhaust gas purifying material. In one embodiment the cartridge provides dual chambers, one for absorbing and absorbing exhaust gas pollutants and the other for catalytic conversion of the same or different exhaust gases. The purifying cartridge is constructed of a foraminous material such as heat and corrosion resistant wire mesh or screen. Similarly, the muffler cartridge is an elongated hollow shell formed of a foraminous heat and corrosion resistant material such as wire mesh or screen. The annular space around the muffler cartridge is preferably filled with a heat-resistant, sound-absorbing, gas previous material.

Abstract: An exhaust duct connector takes the form of a Y-shaped passage. Both of the branches of the Y are adapted to receive ends of upstream exhaust ducts and a leg of the Y is adapted to receive one end of a downstream exhaust duct. A substantially plate-like partition is positioned at the junction of the Y parallel to the single leg. The partition includes a plurality of holes through which exhaust can pass. The partition may include an outer partition member having a plurality of holes and an inner partition having numerous extremely small holes covered by the outer partition member. The partition may contact the adjacent inside wall of the Y-shaped passage, or be spaced from the adjacent inside wall of the Y-shaped passage. The partition may take the form of an airfoil.

Abstract: An improved engine construction is disclosed having a valve train including valves and corresponding valve stems for controlling the intake and exhaust ports, cams for imparting reciprocating motion to the valves by way of the valve train, and a valve spring for biasing each valve toward its closed position and the valve train into tracking relation with the cam. The only element of the valve train coupling a cam to a stem is a cam follower with a depression for receiving the corresponding stem end and a cam engaging surface opposite the depression with the cam follower being held captive intermediate the stem and cam solely by the spring biasing of the stem toward the cam and the engagement of the stem end and the depression. Another feature of the engine resides in the engine block casting which includes an exhaust gas passageway extending from an engine cylinder and including near the end thereof remote from the cylinder an enlarged cavity which defines at least a part of a muffler shell.

Abstract: Apparatus for attenuating upstream gas motion induced by axial acoustic ws in a ramjet engine includes a series of hollow truncated conical attenuators acting to both modify and enhance fuel-oxidizer mixing and offering negligible resistance to downstream gas motion while offering substantial resistance to upstream gas motion within the engine.

Abstract: This invention relates to a tractor muffler structure that is mounted in an upright position and operates to keep moisture and foreign particles from entering the internal workings of a tractor cab engine. The tractor muffler structure includes (1) an inlet pipe member connectable to an exhaust pipe from an engine; (2) a basic housing assembly secured to the inlet pipe; (3) an outlet pipe member secured to the basic housing assembly to convey gases therefrom; and (4) a fluid control assembly mounted within the basic housing assembly and connected to the inlet pipe member and the outlet pipe member. The basic housing assembly resembles a canister having the inlet pipe member extended through a bottom wall and the outlet pipe member extended through a top wall. The bottom wall has a drainage hole therein to allow fluids to pass therethrough.

Abstract: The acoustical energy absorbing baffle has a pair of restricted orifice screens rigidly secured in parallel, spaced relation by a lattice stiffener. The screen-stiffener assembly is immersed in a viscous fluid contained within a tank sealed with an elastic diaphragm. Incident acoustical energy is transmitted through the diaphragm and translated into energy absorbing motion of the fluid through the restrictive screens. A compliant mass is acoustically coupled to the fluid to augment fluid particle velocity through the screens and to further absorb energy.

Abstract: Disclosed is an air cooled internal combustion engine which comprises a cooling fan formed unitarily on a flywheel fixed to one end of an engine crank shaft, a cooling fan case covering the cooling fan and adapted to guide the flow of cooling air generated by the cooling fan toward the engine body, an air cleaner connected to the suction port of the engine, and a silencer connected to the exhaust port of the engine, wherein the suction port is located at the same side of the engine body as the flywheel while the other exhaust port is located at the opposite side of the engine body to the flywheel, and wherein the air cleaner is formed integrally with the cooling fan case.

Abstract: A muffler for combustion engine in which a housing is subdivided into at least two successive reflection chambers. An exhaust gas inlet pipe enters the first input reflection chamber, and intermediate channels are provided for communicating between the reflection chambers. An exhaust gas outlet pipe terminates in the last reflection chamber. A corrugated metal sheet is provided on the inner side of the housing, and cooperates with that inner side so that each corrugation of the metal sheet forms an intermediate channel with the inner side of the housing. The region of the opening of the exhaust gas inlet and outlet pipes is surrounded by a respective chamber housing. Each chamber housing forms a closed reflection chamber and abuts the inner side of the corrugated metal sheet to form a plurality of mutually separated guide channels.

Abstract: An automotive vehicle noise reduction device comprises an under-cover structure fixedly disposed directly under an engine and including a plate member securely connected to a vehicle body, a plurality of covering members which are spaced from each other and fixedly disposed between the plate member and the engine, and a sound absorbing material securely attached on each covering member and located opposite to the plate member, thereby effectively improving noise insulation effect while preventing vehicle fire.

Abstract: Reciprocating pneumatic motor for rock drills and the like wherein a freely-movable hammer piston repeatedly strikes the end of a drill rod, usually a rotating drill rod. Fluid under pressure enters a single, central inlet port in the wall of a cylinder which houses the piston with alternate cycling ports being incorporated into the piston itself. Also disclosed is a novel muffler for such a pneumatic motor.

Abstract: A drill motor rigid enclosure is provided for a rock drill motor. The drill motor is encompassed within the enclosure such that viration, torque, and thrust produced by the motor is isolated from the rigid enclosure, therefore noise reduction of the drill motor is achieved.

Abstract: The present invention provides an exhaust system comprising an elongated hollow casing having an upstream muffler chamber containing an insulated removable cartridge for sound absorbing and sound collecting, an intermediate chamber containing a removable spark and moisture arrester and a downstream chamber having a removable and replaceable cartridge containing exhaust gas purifying material. In one embodiment the cartridge provides dual chambers, one for absorbing and absorbing exhaust gas pollutants and the other for catalytic conversion of the same or different exhaust gases. The purifying cartridge is constructed of a foraminous material such as heat and corrosion resistant wire mesh or screen. Similarly, the muffler cartridge is an elongated hollow shell formed of a foraminous heat and corrosion resistant material such as wire mesh or screen. The annular space around the muffler cartridge is preferably filled with a heat-resistant, sound-absorbing, gas previous material.

Abstract: An automotive type internal combustion engine exhaust muffler has a welded butt joint consisting of the ends of a pipe bushing, a lockseam louver tube, and a partition neck into which the tube is pressed, the welded joint preferably being of a structure produced by the magnet arc process.

Abstract: A muffler (10) for use in conjunction with an interfloor tube and aspirator (20) during the production of multifilament, synthetic yarn is provided. Audible noise which is emitted at the inlet end of the interfloor tube is reduced by up to 10 .DELTA.db(A) through the use of a perforated tube (11), restrictor plate (13) and sound absorbing material (16).

Abstract: An especially compact, highly efficient heat recovery device for use in the cool air return duct of a heating system may be easily installed in existing flue pipes and transfers the ordinarily wasted heat in the exhaust gases flowing through the flue pipe to the cool return air thereby preheating the latter and increasing the efficiency of the heating system. The device includes a three stage heat transfer structure housed within a heat conductive tubular member which cooperate to transfer heat away from the gases into the cool return air by means of conduction, convection and radiation processes. A first stage deflects a portion of the gases toward and into heat exchanging contact with the sidewalls of the tubular member and directs the remaining portion into a gas pervious heat storage trap which comprises the second stage.

Abstract: A muffler for use with internal combustion engines or the like having improved sound attenuation capabilities together with lower back pressure. The muffler has an elongated outer casing connected to inlet and outlet pipes by inlet and outlet transition sections. A central diffuser body is located within the outer casing substantially along the longitudinal centerline thereof. Mounting plates connect the front and rear ends of the diffuser body to the inlet and outlet pipes, respectively, to hold the diffuser body in place. An inner casing is spaced from, and conforms to, the inner surface of said outer casing between transition sections. The inner casing and the side wall of the diffuser body are perforated. Porous or fibrous sound absorbing material is contained within the diffuser body and between the inner and outer casings. The cross-sectional areas of the inlet pipe and the ring between the inner casing and the diffuser body are preferably substantially equal.

Abstract: A flow duct for the delivery of air for ventilation is of round cross section and is surrounded by a prismatic casing over the length of the duct. Sound-absorbing material is filled into the space between the casing and the duct and varies in radial thickness around the periphery of the duct as measured in a plane perpendicular to the axis thereof.

Abstract: The invention relates to encapsulating machines and more especially to the device for putting the capsules in position in the encapsulation head. It consists in the creation in the air duct for propulsion of the capsules of one or more chambers for successive expansions of the air separated by nozzles the ratio of the bores of which is such that the incomplete expansion of the air is obtained in each intermediate chamber and the expansion is complete at the output in the ambient air. In one embodiment the cross-section of the outlet nozzle appears in the form of a flattened tube and the expansion chamber is filled with an acoustic insulation material. (FIG. 4). In another embodiment, a plurality of channels surround the outlet nozzle which communicate with the atmosphere and thereby introduce air into the outlet nozzle, providing a continuous circulation of air round the device. (FIG. 6).

Abstract: An exhaust device is provided comprising a first diverging portion extending into a cylindrical envelope into which is axially displaceably mounted a streamlined conically shaped member adapted to be moved in relationship to the engine rating.

Abstract: An exhaust silencer provided with a catalyst. It includes an expansion chamber with a reflecting wall, and a silencer chamber. A passage joins the two chambers, and a catalyst lies in the passage, preferably on the wall of a tube which forms the passage, where it covers perforations in the tube through which the exhaust gases must pass when they flow from one chamber to the other. An auxiliary catalyst can also be provided in the expansion chamber.

Abstract: An exhaust muffler which includes a tubular metallic core having at least one layer of fiberglass around the tubular core. The core has a plurality of circumferential slots formed therethrough with the slots arrayed in spirals around the core. Each slot extends in a transverse or circumferential direction on the core, and has a width to length ratio of about 1:3 to about 1:5. A pair of spaced baffle bars are extended diametrically across the core at spaced locations along its length, and are oriented at right angles to each other in respect to the direction of extension across the longitudinal axis of the core.

Abstract: Gas turbine exhaust quieting means wherein the low frequency noise which is normally generated by turbulence in the gas turbine exhaust, is suppressed by means of a turbulence suppressing flow distributor. Said flow distributor comprising an elongated, hollow body, having a multiplicity of small holes in the walls thereof. Said flow distributor also providing a means for uniformly distributing the gas turbine exhaust flow over the face of a turbular or splitter type of exhaust gas silencer, which is usually used in combination with the flow distributor.

Abstract: An exhaust gas silencing system wherein standing waves are utilized in a silencing chamber to reduce low frequency components of noise, and a downstream muffler is utilized to reduce the high frequency components of noise. An expansion chamber can be utilized further to reduce the pressure of the sound waves.

Abstract: A sound reducing baffle for air cooled electrical apparatus with a ventilated enclosure comprised of a box-like closure member positioned in front of the ventilating openings and open at the back and top thereof to permit the transfer of air.The sound is attenuated by reflections and absorption within the baffle with little or no interference with the transfer of cooling air to and from the enclosure.

Abstract: A muffler is integrally incorporated with a pneumatic tool by cooperating with the tool housing intermediate the air exhaust chamber for the air motor and atmosphere. An inwardly dished muffler shell includes an exhaust inlet for receipt of exhaust air from the air motor. The shell is selectively positionable and may be combined with screen and additional muffler material as well as a retaining plate in any of a number of combinations to provide distinctive muffling characteristics for the air tool.

Abstract: An exhaust gas muffler for an internal combustion engine. The muffler designed to increase back pressure to the engine within acceptable manufacturer limits and increase the frequency of the sound of the exhaust gas so that the acoustic energy is more easily attenuated when exhausted into the atmosphere.

Abstract: A gas turbine engine exhaust duct of combination circular and rectangular configuration, and accompanying muffler which provides cooling and silencing of exhaust flow from the gas turbine engine. The arrangement utilizes minimum space without sacrifice of performance.

Abstract: A silencer consists of concentric spaced apart longitudinally extending shells connecting two bulkheads, each having an outer imperforate face, the space between the faces of each shell containing noise absorbing material such as rock wool. Each shell has a longitudinally extending duct to enable the gases to escape, the duct in the inner shell being offset in relation to the duct in the next shell; the inner shell is connected to the inlet pipe and the gases escape via the duct of the inner shell, then through the space separating the two shells and finally through the duct of the next shell.

Abstract: A muffler for lowering the exhaust gas noise level of combustion engines has a Helmholtz resonator chamber and a single straight tube member that is provided with a perforated portion outside said chamber large enough for full flow through it of all gas flowing through the muffler, one end of the tube extending into the resonator chamber and the tube diameter, chamber volume, and length of the tube between said one end and said perforated portion being related to and dependent upon each other in accordance with the Helmholtz formula so that the resulting Helmholtz system attenuates a predetermined frequency when the muffler is placed in an exhaust system at or near the pressure antinode of that frequency.

Abstract: A muffler assembly for substantially dampening acoustical vibrations of engine exhaust gases. The muffler assembly includes flow control means, such as a diffuser having a centrally disposed baffle with radially extending deflector vanes having axially extending tabs. The diffuser can be positioned in a tubular expansion joint which is secured to an apertured louver tube within a loosely compact shell of sound attenuating material. The diffuser substantially blocks and restricts the axial flow of exhaust gases along portions of the longitudinal axis of the louver tube, deflects the flow of exhaust gases toward the sound attenuating material and creates turbulent flow.

Abstract: Gas turbine exhaust quieting means wherein the low frequency noise which is normally generated by turbulence in the gas turbine exhaust, is suppressed by means of a turbulence suppressing flow distributor. Said flow distributor comprising an elongated, hollow body, having a multiplicity of small holes in the walls thereof. Said flow distributor also providing a means for uniformly distributing the gas turbine exhaust flow over the face of a tubular or splitter type of exhaust gas silencer, which is usually used in combination with the flow distributor.

Abstract: A silencer quiets the exhaust output from a marine engine by injecting a spray of cooling water into the exhaust passageway to mix with and cool the exhaust gases before output from the passageway. The exhaust passageway preferably enlarges substantially in cross-sectional area in the region where the mixing occurs between the injected water and the exhaust gases for enhancing the cooling effect. An inlet scoop receives water as the boat moves forward, and the water is forced through a line and into the exhaust passageway in a way that breaks the water into drops for contacting and cooling the exhaust gases. A mute that is preferably conical in shape and centered in the exhaust outlet also cooperates to reduce the exhaust noise.

Abstract: A silencing and cooling system for engine exhausts. The system utilizes a silencer body having an axial passage containing barriers, deflectors, and guide vanes. Cooling air enters via an axial inlet at one end and mixes with exhaust gases entering the axial passage from a lateral opening in the body as they travel to the outlet at the other end of the axial passage.

Abstract: A chamber is formed on a powder-actuated tool into which the combustion gases generated by firing the tool are directed. The chamber contains a plurality of baffle plates which absorb noise and provide increased surface area for precipitation of fouling deposits carried by the combustion gases. The plates are easily removable for cleaning. The chamber is formed in a box-like housing which can be secured to a conventional indirect firing tool with minimal adaptation necessary.

Abstract: An attenuator for reducing exhaust noise in engines is provided which includes an exhaust pipe having a flared outlet and a frustoconically shaped attenuator member mounted therein. In an alternate embodiment, vents are provided to increase efficiency. In a further alternate embodiment, the exhaust pipe is combined with a muffler.

Abstract: An accessory or attachment device for existing or newly manufactured internal combustion engines bleeds incompletely burned combustion products from the engine exhaust upstream from the exhaust manifold and returns or recycles the combustion products through the carburetor to the combustion chambers of the engine where complete burning of the products takes place. Carbon monoxide in the final exhaust from the engine is reduced almost to zero and substantially the full energy present in the hydrocarbon fuel is utilized, rather than being wasted into the atmosphere as occurs in conventional engines. The device subjects the recycled combustion products to violent agitation and comminution before returning them through the carburetor to the engine fuel induction system.

Abstract: For use in a muffler of an internal combustion engine improved flame-out apparatus includes first and second L-shaped screens each having a longitudinal section and a transverse section. The transverse sections are axially spaced apart and the space therebetween is occupied by a pair of axially spaced apart, transversely oriented perforated partition plates and flame extinguishing means.

Abstract: The application discloses a new silencer for internal combustion engines. This silencer comprises an internal resilient tube capable to vibrate longitudinally and permeable to the exhaust gas and an external sheath. An end piece closes the internal tube. Spacers are secured to the internal tube and another end piece provided with apertures is secured to the end of the external sheath. The exhaust gases exit from the internal tube through the space comprised between the spacers and the external sheath towards said apertures in the other end piece.