Abstract: A fire suppression nozzle includes a first conduit including an inlet and an outlet, a second conduit coupled to the first and including a plurality of outlets spaced apart from a second plurality of outlets. The nozzle includes a first annular sound absorbing member positioned on a first side of the outlet and a second annular sound absorbing member positioned on a second side of the outlet wherein the first conduit provides inert gas to the second conduit. The inert gas exits the outlet in a first direction and a first portion of the inert gas is directed toward the first plurality of outlets in a second direction and a second portion is directed toward the second plurality of outlets in a third direction opposite the second direction, wherein the second and third directions are generally perpendicular to the first direction.

Abstract: An air duct assembly for a vehicle air distribution system includes a first duct defining a first passage and a second duct defining a second passage separate from the first passage. The first and second passages are fluidly connected to a common outlet for flowing air to a windshield of the vehicle. The assembly further includes a third duct defining a third passage for flowing air to a side glass of the vehicle. The second and third passages are fluidly connected to a common inlet for receiving air from the blower motor. The third passage is fluidly connected to a lateral outlet that is separate from the common outlet, with the lateral outlet flowing air to a side glass of the vehicle. The assembly further includes at least one acoustic baffle disposed within the second passage and configured to reduce a transmission of the blower noise through the second passage.

Abstract: A novel design for desiccant air dryer pneumatic mufflers includes a core comprising a perforated inner tube with baffles attached to the outside surface of the inner tube. The inner tube is positioned in the interior of an outer tube, and a cap is positioned on one end of both tubes. The interior portion of the cap is solid so that it blocks the flow of air at the end of the inner tube, forcing the air to flow through the perforations in the inner tube and into the outer tube. The perimeter of the cap is perforated so that the air exits the muffler.

Abstract: A muffler structure contains: a body, a first cover unit, and a second cover unit. The body includes an accommodation tube, fiber cotton, and a first mesh portion. The accommodation tube has an accommodating space and an internal fence. The first cover unit includes a manifold connection portion, a first polygonal cap, a hollowly tubular mesh having multiple orifices, a second mesh portion, and a stainless steel mesh. The second cover unit is fixed on a rear end of the accommodation tube of the body opposite to the first cover unit, and the second cover unit includes a second polygonal cap and a silencer. The second polygonal cap is covered on the accommodation tube of the body, and the second polygonal cap has a receiving portion defined in a free end thereof and configured to accommodate the silencer.

Abstract: A multi-stage, torispherical drilled-hole dump device which mounts on the surface of an air cooled condenser (ACC) duct, and provides a compact and lightweight method for discharging steam into the duct by presenting a large surface area which minimizes noise and vibration, while also having a low-profile shape which minimizes projection into the duct and flow disturbance in the duct.

Abstract: The invention is a suppression device to eliminate flash, noise and smoke, collectively “gas” which is created by explosion of a high-powered rifle hammer striking a bullet, from escaping down a barrel of the rifle so as to expose a shooter's location. The device is physically located nearest to the receiver of the rifle. It operates by machine cutting the barrel to form a diverter which directs the gas into a chamber. Inside the chamber are five concentrically and longitudinal arrayed tubes. The gas travels a longer path than the bullet by passing through the tubes, echoing back and forth until dissipation of the gas.

Abstract: In accordance with at least one embodiment: a muffler with a case (comprised of at least one inlet, at least one outlet, and a body), and elongated members comprised of material capable of a predetermined resonance. The elongated members have sufficient length after their final point of attachment to vibrate when exposed to flowing exhaust gasses. This vibration results in resonance that is noise canceling and/or sound enhancing. The muffler may also contain any combination of sound baffles, sound absorbent material, and other sound altering devices.

Abstract: An exhaust stack includes an inlet section extending along a first axis and an outlet section extending along a second axis. A co-axial silencer is arranged in one of the inlet section and outlet section. The co-axial silencer includes a plurality of concentric baffles configured and disposed to absorb acoustics generated by fluid flow through the exhaust stack.

Abstract: A portable pneumatic power wrench has a housing with a handle, a motor, a pressure air inlet passage, and an outlet passage for ducting exhaust air from the motor out of the housing. An outlet unit is connected to the outlet passage and has a first outlet opening section forming a main exhaust air flow path, a second outlet opening section forming an additional exhaust air flow path, and a manually operable valve arranged to control the additional exhaust air flow path by opening or closing the second outlet opening section. The total outlet flow area of the main exhaust air flow path and the additional exhaust air flow path gives an augmented torque output of the power wrench.

Abstract: This silencer (10) for a motor vehicle exhaust line of the type comprising: a casing (12) internally delimiting an exhaust volume; an exhaust gas inlet (16) opening into the exhaust volume; and an exhaust gas outlet pipe (18) communicating with the exhaust volume and having an outlet orifice (30) to the outside of the silencer (10), is characterized in that the outlet pipe (18) comprises a section (32) pressed against the casing (12), the casing (12) having at least one perforation placing the pressed section (32) in communication with the exhaust volume.

Abstract: A firearm suppressor includes at least one baffle disposed within a cylindrical housing. The baffle includes a distal-facing conical baffle having a wider end and an opposing narrower end; and a proximal-facing conical baffle intersected by the distal-facing conical baffle such that the narrower end of the distal-facing conical baffle extends beyond a wider end of the proximal-facing baffle, wherein a central bore extends through both the distal-facing conical baffle and the proximal-facing conical baffle.

Abstract: A silencer includes an inner cylinder that is connected to an exhaust pipe and a partition cylinder that is accommodated in a housing and that sections an expansion chamber in the housing. A group of partition-cylinder small holes is formed in the partition cylinder, and a group of inner-cylinder small holes is formed in the inner cylinder. The group of partition-cylinder small holes and the group of inner-cylinder small holes do not overlap each other in an axial direction, and are separated from each other by a predetermined distance in the axial direction.

Abstract: A noise and vibration reduction system for an engine affixed to a body and a method for reducing vibrations in the body produced by that engine during operation. The present invention is particularly related to noise and vibration reduction in auxiliary power units installed on long-haul trucks and similar types of transportation vehicles. The primary noise and vibration reduction components of the present invention include an air intake silencer, a vibration tuner, and an engine speed limiter.

Abstract: The present invention is for a triangular cross section symmetrical engine exhaust muffler for an internal combustion engine. Its internal design provides baffles symmetrically disposed about a plane centrally located equidistant from the ends of a tube having a triangular cross section. The design has three baffles spaced to minimize backpressure but angled to enhance acoustic reflections within the chamber formed by the tube having a triangular cross section, baffles, and the affixed endplates including the inlet/exhaust ports. These acoustic reflections serve to modify the sound emanating from the exhaust manifold or manifolds of the internal combustion engine. The muffler chamber also serves to smooth out the pulsating gas flow emanating from the engine as a result of the combustion cycle.

Abstract: An exhaust system for a vehicle, such as a motorcycle or other straddle-type vehicle, that achieves miniaturization while providing advantageous noise reduction characteristics. The exhaust system is associated with an engine of a vehicle and includes an exhaust pipe connected to the engine and a silencer. A conical member is positioned within the silencer and includes an upstream end and a downstream end. At least a portion of a side wall of the conical member includes a plurality of through-holes. The conical member is oriented such that a radial dimension of the conical member increases in a direction from the upstream end to the downstream end.

Abstract: A silencer includes a cylindrical member held between a body connected to an exhaust side of a fluid pressure device and a disk-shaped retaining member. A net-shaped sound absorber is disposed around an outer circumference of the cylindrical member. A pressure fluid flows from the body into the interior of the cylindrical member and is discharged toward the sound absorber through a plurality of first through fifth exhaust holes formed in the cylindrical member. Accordingly, dust in the pressure fluid is removed by the sound absorber, which is formed of a plurality of stacked filters, and further, the pressure fluid is discharged to the outside after exhaust noises have been absorbed by the sound absorber.

Abstract: Silencer of exhaust gases, in particular for motor vehicles, comprising an inlet opening (13) and a cylindrical coat (1) provided with an outlet pipe (29) at its opposing end, said cylindrical coat (1) has an internal division into at least four working sections (5, 6, 7, 8) containing axially arranged elements, especially suppression elements, expansion chambers, a whirl chamber, resonators and twirling, deflecting, and accumulating elements, confined with at least three crosswise arranged partitions (2, 3, 4), while the cylindrical coat (1) opposite to the outlet tube (29) is provided with an inlet section (10) freely encompassing its first working section (5) provided with inlet holes (18) of exhaust gases, said inlet section (10) being attached to the surface of the cylindrical coat (1).

Abstract: A system and method for dissipating at least one pressure wave in an exhaust gas flow is disclosed. A vehicular exhaust system directs the exhaust gas flow through a plurality of coaxial and perforated generally cylindrical tubes contained within an insulated canister towards a perforated partition plate. Through a series of apertures in the tubes and plate, the at least one pressure wave is dissipated such that sound attenuation is achieved without output loss from the engine.

Abstract: An automotive muffler includes an external tube consisting of a first widened portion, a first tapering portion, and a first narrow portion, the first widened section having a sealing wall with a through hole at the front end thereof; an internal tube consisting of a second widened portion, a second tapering portion, and a second narrow portion, the internal tube being disposed within the external tube, a plurality of vent holes being formed in the wall of the second widened portion; an internal guide tube consisting of a third widened portion, a third tapering portion, and a third narrow portion, the internal guide tube being disposed within the internal tube, a plurality of vent holes being formed in the wall of the third widened section that is disposed within the internal pipe; and a plurality of partitions interposed between the first widened section and the second widened section as well as between the second widened section and the third widened section.

Abstract: An exhaust muffler for an internal combustion engine included in a motorcycle includes a perforated inner pipe (32), an outer pipe (31) coaxially surrounding the inner pipe (32), and a glass wool mat (33) packed in a space between the inner pipe (32) and the outer pipe (31). A three-layer protective structure is formed by winding an inner stainless steel wire mesh (34) wound around the inner pipe (32), winding a stainless steel wool mat (35) around the inner stainless steel wire mesh (934), and winding an outer stainless steel wire mesh (36) around the stainless steel wool mat (35). The glass wool mat (33) is wound around the three-layer structure. The three-layer structure extends the life of the glass wool mat (33) even if the temperature and pressure of the exhaust gas discharged by the internal combustion engine increase.

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

Abstract: The current invention is device for lowering the air velocity and inherent noise of high-speed air released from a closed system, comprising a straight pipe module with an outer tube and a concentric inner tube creating an annular space therebetween. The inner tube has interior fins at the inlet, which initiate rotation in an airflow directed therethrough, and interior fins at the outlet, which arrest the airflow rotation. Perforations along the length of the inner tube, from inlet fins to outlet fins, permit the release of a turbulent outer zone of the airflow, permitting the high velocity core of the airflow to expand and slow, reducing the noise of the airflow.

Abstract: A silencer for use with ultrasonic meters to reduce stray ultrasonic noise that could cause measurement inaccuracies. The silencer comprises a tubular body having at least two baffles spaced apart from one another. The baffles are preferably formed of an open-cell, reticulated metal foam material that absorbs noise in the ultrasonic range of frequencies under high-pressure operating conditions. The silencer is a reasonable flow conditioner and can be mounted directly to the meter without disturbing the flow. The silencer reduces the level of ultrasonic stray noise by absorption. Ultrasonic noise waves are partially reflected between the baffles and along their length as the waves move between baffles. With each reflection, the baffle material absorbs energy that is lost by friction in the pores of the foam material. Through this process of the ultrasonic waves being reflected and the noise being incrementally absorbed, the energy of the ultrasonic wave is attenuated.

Abstract: A muffler has an elongated generally cylindrical casing having inlet and outlet ends, an elongated generally frustroconical baffle in the casing adjacent the inlet end with the smaller diameter portion being spaced from the inlet end. The peripheral wall of the baffle has closely spaced perforations over the major portion of its axial length and is spaced from the shell to provide a chamber thereabout. A generally cylindrical baffle has one end extending over the smaller diameter portion of the frustroconical baffle and has its peripheral wall spaced from the casing to provide a chamber thereabout. The peripheral wall of the cylindrical baffle has closely spaced perforations over most of its length. Exhaust gases enter the frustroconical baffle and exit through the perforations therein, move axially in the casing thereabout, and then pass through the apertures into the cylindrical baffle.

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

Abstract: Within an exhaust duct are positioned a plurality of concentrically arranged, open ended, right cylinders supported axially within the exhaust duct, wherein each of the cylinders includes an inlet end and an exit end. The inlet ends are positioned in sequential downstream order from the outermost of the cylinders to the innermost of the cylinders. The cylinders are graduated in length sequentially with the outermost cylinder being shortest in length and the innermost cylinder being longest in length. The inlet ends of each of the cylinders provide a circular leading edge with a sawtooth conformation. An elongated smooth rod is positioned on the longitudinal axis of the exhaust duct with a downstream end of the rod providing a flared portion positioned at the mouth of the innermost of the cylinders.

Abstract: A compact muffler has a straight through inner cylindrical casing surrounded by an outer cylindrical casing defining a closed ended sound attenuating chamber therebetween. Within the outer chamber a plurality of axially extending, radially overlying, cylindrical intermediate casings form a plurality of annular sound attenuating passages. The sound passages are configured to have entrances in fluid communication either with an especially configured slot in the inner casing or between certain passages to define a plurality of discrete sound paths, with each sound path having a set length sufficient to generate a reflection wave for attenuating a sound wave having a frequency correlated to the distance of the sound path.

Abstract: The present invention relates to a muffler used in a motor vehicle for cooling the engine exhaust gases. The muffler has an internal tubular member defining an internal chamber and a middle tubular member concentric in relation to and supported on the internal tubular member. The internal and middle tubular members form a first ring-shaped chamber adapted to connect to the exhaust pipe. The muffler also has an external tubular member being concentric in relation to and supported on the middle tubular member. The middle tubular member and the external tubular member form a second ring-shaped chamber with a third inlet portion. Hence, engine exhaust gases of the motor vehicle pass through the first ring-shaped chamber and are sufficiently cooled and depressurized by cooling air that passes through the internal and second ring-shaped chambers.

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 casing for audiovisual equipment presents an outer appearance giving the impression of integrating a hole area formed of a plurality of sound transmitting fine holes with the casing, thereby making the hole area unnoticeable. This allows a viewer to easily concentrate on the screen by eliminating anything noticeable and distributing from the area surrounding the screen, and also gives the outside of the casing a luxurious appearance. In order to make the hole area unnoticeable, maintain good volume and quality of sound from the speaker, and arrange the diameter .o slashed.d mm of the tapered fine holes to be practically the smallest, the relationship between the diameter .o slashed.d mm and the thickness T mm of the casing must be expressed by the following formula: (1/6).times.T mm.ltoreq..o slashed.d mm.ltoreq.0.5 mm. When the fine holes are formed to be straight, the relationship between the diameter .o slashed.ds mm and the thickness T mm of the casing must be expressed by the following formula: (1/5).

Abstract: A compact muffler has a straight through inner cylindrical casing surrounded by an outer cylindrical casing defining a closed ended sound attenuating chamber therebetween. Within the outer chamber a plurality of axially extending, radially overlying, cylindrical intermediate casings form a plurality of annular sound attenuating passages. The sound passages are configured to have entrances in fluid communication either with an especially configured slot in the inner casing or between certain passages to define a plurality of discrete sound paths, with each sound path having a set length sufficient to generate a reflection wave for attenuating a sound wave having a frequency correlated to the distance of the sound path.

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: A muffler arrangement includes a muffler with an essentially cylindrical housing having a face end with a central entrance opening and at least one exit opening arranged other than centrally on the face end. Baffles are disposed within the housing, the baffles being concentrically arranged pipe cylinders which extend alternatingly into one another and are closed at one end, for effecting a multiple deflection of gases traveling from the central entrance opening to the at least one exit opening. A coupling structure is secured to the muffler housing, for carrying the muffler in an operating position. The coupling structure has a central passage for connecting the muffler to an exhaust outlet of a machine, and has an other than central channel, surrounding the central passage, for connection to an exhaust gas output conduit for outputting exhaust gases from the muffler arrangement.

Abstract: A muffler for use on the exhaust system of the motor vehicle. The muffler has a central pipe which is surrounded by an outer pipe which leaves an annular space between the two. The outer pipe is open at both ends and the annular space is filled with a sound deadening material. The central pipe has openings which pass to the annular space and a perforated sound deadening member is affixed to the inner surface of the central pipe. Preferably, the outer pipe is outwardly flared at its upstream end, and the perforated sound deadening member is conical in shape.

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 cross-section having no baffles or flow reversals. The muffler utilizes both reactive and dissipative components and includes an outer annular resonating chamber and an inner sound absorbing chamber. The muffler's configuration produces effective broad band noise attenuation even at lower frequencies, yet low backpressure.

Abstract: The noise generated by onrushing air which is produced by an air blower for use in conjunction with pneumatic conveying equipment is substantially reduced by directing the air flow through an enclosed housing from an air inlet opening to an air outlet opening mainly via hollow tubular members made of air pervious material shaped in a snake-like or serpentine fashion between the air inlet and the air outlet openings.

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: A muffler for use with an underwater vehicle. The muffler is mechanically attached to an exhaust tube or aft end of the underwater vehicle and has an hydrodynamic shape and perforated exterior that results in the production of less noise by the vehicle. Large bubbles have been determined to be offensive due to lower frequency collapsing noise which produces a louder vehicle exhaust. The present invention is perforated with holes to break up the flow of exhaust gas from the vehicle into small diameter bubbles that are emitted into the water. The present invention has a contoured outer wall that matches the contour of the underwater vehicle to provide for the hydrodynamic flow of water around the vehicle as it is propelled through the water. The present invention eliminates hydrodynamic voids at the aft end of the vehicle that would normally allow smaller bubbles to coalesce into large bubbles.

Abstract: Muffler assembly for an engine comprises an outer cylinder constituting a muffler body, an inner cylinder coaxially disposed in the outer cylinder, a connection cylinder disposed inside the inner cylinder having one end on an upstream side and another end on a downstream side, a partition plate disposed inside the inner cylinder at the downstream end of the connection cylinder, first and second silencer chambers formed at the upstream and the downstream end of the connection cylinder, respectively, an inlet, pipe through which an engine exhaust gas is introduced into the muffler body, and an outlet pipe having an upstream end disposed inside the inner cylinder and a downstream end opened outward of the muffler assembly. The connection cylinder has an upstream end portion in which a plurality of holes are circumferentially formed.

Abstract: A vertical exhaust pipe having an inner pipe with an upper opening. An outer pipe is positioned around the inner pipe and has an end portion that extends beyond the upper opening in the inner pipe, said end portion defining an outlet through which exhaust gas exits the outer pipe. A mechanism is coupled with the inner pipe for blocking rain that has entered the outer pipe from falling through the opening in the inner pipe. A ledge mechanism is positioned beneath the upper opening in the inner pipe and between the inner and outer pipes for forming a chamber within which is held rainwater that has entered the outer pipe. A drainage mechanism allows rainwater in the chamber to pass to the exterior of the outer pipe.

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: Provided is a device for dissipating, safely and in an environmentally sound manner, a high pressure fluid discharge from a gas well. The device is locatable in an earthen pit and connectable to the end of a discharge conduit. There is an open-bottomed hood having a front wall, a rear wall and curved side and upper wall, with the well discharge conduit connecting through the front wall. Mounted within the hood is a first dissipator tube having a perforated wall and a significantly larger diameter than the discharge conduit, and including a front end connected to the discharge conduit. A deflector plate, having a multitude of perforations, is mounted across this first tube near its open rear end. A second, open-ended dissipator tube has a larger diameter than the first dissipator tube, and an array of apertures in its lower wall.

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 control valve includes a valve body with a fluid inlet and a fluid outlet. A valve seat is mounted within the valve body between the inlet and outlet. A valve plug is reciprocally mounted within the valve body to engage the valve seat. A plurality of valve cages are removably mounted on the valve seat and surround the valve plug. The valve cages are mounted to define axial flow galleries. One of the valve cages includes a plurality of apertures and fins that extend radially into a gallery between the first cage and a second cage. The second valve cage is adjacent to and surrounds the first valve cage. The second valve cage includes a plurality of apertures and fins that extend into the gallery area between the second cage and a third cage. The third cage surrounds and is adjacent the second cage. A plurality of apertures are defined in an upper portion of the third cage member.

Abstract: A plug section for a muffler, including an outer body and having an inlet pipe for introducing exhaust gas into the body. The inner end of the inlet pipe located within the body portion is closed off. Surrounding the inlet pipe is a conical baffle having a small diameter end secured to the inlet pipe to provide a tapered chamber between the inlet pipe and the conical baffle, while the space between the conical baffle and the outer body defines an outer chamber. Both the inlet pipe and the conical baffle are provided with a plurality of perforations. Exhaust gas entering the inlet pipe flows outwardly through the perforations in the inlet pipe to the tapered inner chamber and then flows through the perforations in the conical baffle to the outer chamber. The use of the perforated conical baffle provides a substantial improvement in sound attenuation, reducing both the shell noise level and the outlet noise level.

Abstract: The sound absorber includes a main body (1), a housing component (2) attached thereon and a cap (3) threaded onto the main body. The compressed air exiting from the compressed-air vibrator flows from a first chamber (4) into a second chamber (5) provided with labyrinth-like baffles (7) and from there into a larger third chamber (6). The relieved compressed air then flows outside through an annular outlet slit (8a). Through rotation of the cap (3) there can be varied the cross-section of the outlet slit (8a). The cap (3) thereby also serves as a throttle valve.The sound absorber is insensitive to oil-containing compressed air and, without an auxiliary throttle valve, facilitates a correlatable throttle of the exiting compressed air.

Abstract: A combined muffler and engine exhaust filter comprises a fixed outer shell and an inner shell. The inner shell is formed from two concentric perforated tubes held in fixed relationship to each other. Granulated or powdered filtering material fills the space between the concentric tubes. The engine exhaust is connected to one end of the combined muffler and filter. An exhaust pipe is connected to the other end. The structure which holds the inner shell and outer shell in fixed relationship to each other also causes the engine exhaust to pass through the perforations in one tube and move in a radial direction through the filter material and through the perforations in the other tube. The length of the concentric tubes, the size and number of perforations, and the thickness of the filtering material between the concentric tubes selected to adequately filter the engine exhaust without incurring an objectionable increase in back pressure.

Abstract: An apparatus and method is provided for venting high pressure gas to a lower pressure region with a minimum of noise. A high pressure vent valve controls egress from a high pressure gas source. In order to limit the generation of noise downstream of the vent valve, at least one control orifice is provided which is configured to have a flow velocity through a throat section thereof of the speed of sound, and with a pressure downstream of the throat being the same as the throat pressure. In this manner, the pressure is reduced by about half at each control orifice, with no or little noise generation. Downstream of these sonic velocity control orifices, sound attenuating means including radially extended passages lined with sound-baffling structure are provided to reduce any residual noise in the flowing gas as it passes into the region of lower pressure.

Abstract: A combination muffler and air filter is provided having a central tubular member with spaced longitudinally disposed elongated slots. A disposable canister on the central tubular member is removably held in position by retainer caps engaged on the ends of the central tubular member. One of the retainer caps is adapted for connection to the exhaust conductor from a pneumatically operated device. The disposable canister has a perforated cylinder encasing a series of stacked annular members having both muffling and filtering properties. A perforated sleeve in the disposable canister supportively engages the inner periphery of the stacked annular members. A closure disc, fixed on each end of the perforated cylinder, holds the stacked annular members in a compact and compressed condition.

Abstract: An absorption muffler for flowing gases and particularly for exhaust gases from internal combustion engines comprises a housing which is of oblong shape and has spaced apart semicylindrical short side walls, with long side walls on each side which are synclinally drawn in the middle thereof. Parallel inlet and outlet pipes are connected into the front wall and extend substantially up to the rear wall, and they are located in substantially parallel relationship centered within the respective short side wall semicylindrical portions. An inlet channel is defined on the interior of the housing which extends in a helical curve around the inlet pipe, which in one embodiment has a single convolution and in another embodiment has a plurality of convolutions. This inlet channel connects to a similarly constructed outlet channel designed around the outlet pipe through an obliquely extending connecting channel. The inlet channel comprises either a single convolution or a plurality of convolutions.