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: A suppressor for reducing the muzzle blast of firearms or the like. Several separate absorbent elements are aligned in tandem within a tubular housing, and adjacent absorbent elements are separated by triangular baffles which expose end portions of adjacent absorbent elements. These exposed end surface portions enhance dispersion of propellant gases into and through the absorbent elements. The absorbent elements preferably are made of a knitted ferrous or non-ferrous wire mesh, providing a number of tortuous paths for gas dispersion into the absorbent elements and lowering the temperature of the gases to reduce the noise of the muzzle blast.

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: Disclosed in an exhaust muffler for internal combustion engine such as opposed twin cylinder 2-cycle internal combustion engine of simultaneous ignition type for driving a chain saw. The muffler is connected at a plurality of points thereof to portions of the engine such as cylinders, characterized by comprising a corrugation S for absorbing thermal distortion provided in at least one side wall of the part of the muffler between adjacent portions at which the muffler is connected to the engine.

Abstract: A fluid operated vacuum device for manipulating a workpiece includes a rectangularly shaped metal body having a plurality of fluid passageways therein. One passageway communicates with a suction cup for creating a vacuum between the cup and the workpiece. Another fluid passageway terminates in an exhaust opening on one end of the body over which there is secured a plastic muffler for dispersing and silencing fluid exiting from the body. The muffler is substantially hollow and includes a plurality of openings in one side thereof through which exhaust fluid may escape into the ambient atmosphere. The effectiveness of the muffler is increased by a recess in the body circumscribing the exhaust opening, a perforated baffle member within the muffler, and a series of dimples in an interior wall of the muffler upon which exhaust fluid impinges.

Abstract: A suction silencer for suppressing generation of noise caused by gas or air sucked by a machine such as a compressor, internal combustion engine or the like. The suction silencer has amounting seat by which it is mounted on the suction side of a machine such as an internal combustion engine. The mounting seat has an opening leading to the suction port of the machine. An inversed conical surface protrudes from the peripheral edge of the opening. A lid member is attached to cover the inversed conical surface such that a small gap is left between the inner surface of the lid member and the large-diameter end of the inversed conical surface. The lid member has an inversed conical member which projects into the space defined by the conical surface so that an annular passage is formed between the inversed conical surface and the peripheral surface of the inversed conical member.

Abstract: The physical size of an inlet plenum (2) for a cluster of pulse combustors (1) may be reduced while maintaining a tuned condition for noise cancellation by constructing the plenum with an annular chamber (8) having internal baffles (20, 21) which make the acoustic path length through the annular plenum (2) substantially larger than its circumference.

Abstract: An exhaust muffler for a two-cycle opposed cylinder engine of simultaneous ignition type having two cylinders opposing to each other in the horizontal direction. The muffler has conical members disposed to oppose to exhaust ports of the cylinders, the exhaust ports being arranged in a side-by-side relation. The conical members form conical annular discharge passages leading from respective exhaust ports. The discharge passages have flattened peripheral outlets of different opening areas. The flows of the exhaust gas from respective cylinders are introduced through the flattened peripheral outlets of the discharge passages into a common diffusion chamber, so that the attenuation of the pressure waves and release of heat of exhaust gas are promoted to reduce the exhaust noise of the engine.

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: 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 rotational mechanism to be disposed midway in a fluid passage may be utilized in a silencer, rotary pump, or the like. The mechanism is essentially provided with a casing defining a spherical chamber, a pair of shafts respectively having axes passing through the center of the interior space of the casing and crossing each other in a plane substantially perpendicular to the flow direction of the fluid, and a pair of impellers having at least two flat plate vanes and at least two bent vanes alternately positioned to the flat plate vanes. The impellers are related to each other such that one flat plate vane is abutted on one bent vane of the other impeller so that every two vanes can constantly partition the spherical space to be able to diminish the noise of the flow or to transport the fluid as a rotary pump with one impeller being driven and the other impeller being idly rotated, by making isolated spaces of different volume for creating the force of pushing away the fluid.

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 lightweight muffler and method for muffling a noise component of a stream of gases is disclosed. The muffler includes a chamber in which gases are directed side-by-side streams flowing in opposite directions. The streams are in contact with each other for the generation of sound dampening eddy currents in the chamber, but such contact does not break down the continuous, low resistance flow of gases through the muffler. The chamber is advantageously formed as an expansion chamber in which gases: enter one end of the chamber as an annular stream concentric with the inlet pipe to the muffler, travel along the inlet pipe to the other end of the chamber, are reversed, and travel as a concentric annular stream of greater diameter in the opposite direction down the length of the chamber for discharge into a passageway leading to the outlet tube of the muffler.

Abstract: An expansion-type muffler for internal combustion engines, interposed in an exhaust system, and provided with a chamber with a substantial volume. The chamber communicates with the up-stream and down-stream sides of the exhaust system. A plate member is connected with an inner wall of the muffler body, and is provided in the body so that all of the connecting points between the plate member and the inner wall are not disposed in the same plane perpendicular to the longitudinal axis of the muffler body.

Abstract: A hollow, generally conical member is provided in a cylindrical portion of a muffler shell and has a surface cooperating with the shell to compress oncoming exhaust gases, the surface being of a special curved configuration calculated for reflecting impinging gas flow in a non-linear pattern which results in the development of pressure waves that arrive at an open exhaust port of the engine at the proper time for providing efficient scavenging and/or supercharging. The generally conical member also serves as an expansion chamber and, in one embodiment thereof, an elongate tube is provided for conveying gases axially thereinto while elongate perforations are provided in the rear end wall thereof for conveying gases therefrom. In a second embodiment thereof, a plurality of radial openings are provided for conveying gases thereinto while a tube extends axially through an end wall thereof for conveying gases therefrom.

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: A multiple flow marine muffler constructed of resilient material having an elongated generally cylindrical hollow shell with reduced diameter inlet and outlet portions, and longitudinally spaced pairs of opposed baffles within the shell which define a plurality of chambers decreasing in axial length from the chamber adjacent the inlet portion to the chamber adjacent the outlet portion. The several pairs of baffles are so shaped, sized and oriented as to provide multiple flow paths for exhaust gases and cooling water through the muffler, namely, a central straight through path for engine idle condition, a first pair of undulating paths in side by side out of phase relation, and a second pair of undulating paths in side by side out of phase relation which are oriented in the cylindrical shell 90.degree. away from the first pair.

Abstract: A noise suppressor for fluid systems may comprise: a cylindrical housing, having an inlet and an outlet, through which fluid may flow and a baffle assembly disposed in the housing providing a path for the flow of fluid whereby the flow is diverted from one side of the housing to the other as fluid flows between the inlet and outlet. A perforated plate member may also be transversely disposed in the housing between the baffle assembly and either the inlet or outlet.

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: An `in-line` unit for use in compressor station piping, arranged to reduce the level of noise generated when the blowdown valves of the station piping are opened in an emergency to vent the high pressure gas therein to atmosphere, the unit comprising a pipe section having a plurality of orifice plates the number and hole area of which is designed to ensure sub-sonic flow through each plate. The unit is preferably used in combination with a modified form of silencer element connected `in-line` downstream thereof.

Abstract: A noise attenuator or muffler for a compressed air tube type heater is disclosed. The muffler exhaust air through exit apertures located about its periphery and due to its unique design substantially avoids the formation of ice in the muffler.

Abstract: A muffler for exhaust gases is constructed with a small casing skirting a portion of an exhaust gas inlet pipe. The end of the casing nearest the exit port of the pipe is blocked and provided with a layer of sound absorbing material. The exhaust gases exiting the pipe turn within the layer and flow back up the outside of the pipe inside the casing and exit at a point near the upper end of the casing. The structure has sound arresting properties, particularly for high frequency sounds.

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 two-piece outer casing encloses a volume with a central divider plate which extends the length of the casing. The two portions of the casing are bolted or otherwise clamped about the divider plate. Each half of the outer casing has angled inner ribs or diverters. The diverters in one casing extend at an opposite angle to the longitudinal axis of the central plate as do the diverters of the other outer casing. The inner edges of the diverter seal against the surface of the central plate. The transverse dimension of the central plate is less than the transverse dimension of the diverters and the outer casing such that an exchange aperture is defined between the central plate and the inner surface of the outer casing between adjacent pairs of diverters. The casing has an exhaust input port and an exhaust outlet port at opposite ends and opposite sides.

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.