Abstract: A muffler of the expansion type comprises an inlet pipe and an outlet pipe connected with each other through a main body. Minimization of pressure pulsation is achieved by a variety of means including appropriately-located apertures in those portions of the walls of said pipes within said main body, an apertured partition within said main body so located that exhaust gas passes through said partition, and appropriate tapering of said pipes. A foamed, heat-resistant material may be positioned over said apertures in said walls of said pipes. Pipe constructions suitable for mass production and pipe-to-main body constructions free of the danger of separation during prolonged use are shown.

Abstract: An exhaust system for an engine of a motorcycle is disclosed having catalytic and silencing mufflers arranged in adjacent side-by-side series flow relationship, the catalytic muffler extending rearwardly of the motorcycle, and, adjacent its rear end, being interconnected with the silencing muffler, the silencing muffler including plural expansion chambers which are interconnected in flow reversal relationship for gases to be exhausted rearwardly of the motorcycle.

Abstract: In the present invention, a second expansion chamber which includes a second diffuser is provided in pneumatic connection with the prior art first expansion chamber of an exhaust system for a two-cycle engine. The second expansion chamber creates a second pressure drop or relative vacuum substantially adjacent the point of pneumatic connection between the first and second expansion chambers, which acts to draw-out the exhaust gases present at the rear-cone shaped portion of the first diffuser. The second pressure drop or relative vacuum created by the second expansion chamber of the present invention thus overcomes the deficiencies caused by the pressure increase produced by the rear-cone shaped portion of the first diffuser. Several embodiments of the present invention are disclosed.

Abstract: A device for treating flowing working gases in order to reduce their operational noises and in most instances also to increase their operating efficiency comprises a flowing working gas operating device which has a discharge conduit with at least one discharge opening for the outflow of the working gas. A check valve is associated with the discharge and includes an elastic valve member movable to close the opening when the flow thereof decreases to a predetermined amount for example as determined by the reduction of pressure of the gases so as to prevent any back flow into the conduit which is likely to produce noise.

Abstract: A muffler for internal combustion engines and comprising a housing having an inlet passageway for admitting exhaust gases into the interior of the housing and an outlet passageway for discharging the exhaust gases from the housing, the interior of the housing providing a fluid passageway having a cross-sectional area greater than the cross-sectional area of the inlet and outlet passageways for reducing back pressure as the gases move through the muffler, baffles disposed within the housing and in the fluid passageway for providing a tortuous path of travel for the gases moving between the inlet and outlet passageways to increase the length of the travel of the gases through the muffler and to provide alcoves or pockets in the interior of the housing for cushioning the flow of the gases therethrough in order to equalize the pressure within the muffler, and a passageway providing communication between the interior of the housing and the combustion chamber of the engine for directing a portion of the hot exhaust

Abstract: An exhaust silencer system for piston type internal combustion engines hag a wet-exhaust, having a muffler and a muffler bypass which contains water at slow and moderate engine speeds, the water being expelled by the exhaust gas pressure at high engine speed, opening said bypass to the flow of exhaust gases thus reducing the exhaust back pressure occurring in the muffler.

Abstract: An exhaust silencer for use with small vehicles which use low speed engines and have minimal space available for the silencer while still requiring a long exhaust path to silence the low frequency engine pulsations. The silencer includes a silencer chamber with an axis, and an exhaust pipe with a U-shape, one arm of which extends axially into the chamber, and the other arm of which extends parallel to the axis outside of the chamber, both for a substantial part of the length of the chamber. At least the bight of the U-shaped pipe is double-walled to minimize the emission of pulsations from that portion of the exhaust pipe.

Abstract: An exhaust system of an automotive vehicle, comprises a muffler having a front end face to which an exhaust pipe is connected, and a tail pipe connected at its one end to the front end face of the muffler, the other end of the tail pipe being opened rearward of a rear end face of the muffler, so that the tail pipe is rendered considerably long to effectively silencing exhaust noise even in a small-sized passenger car having a narrow rear overhang.

Abstract: The invention refers to a silencer or muffler for internal combustion engines, particularly for two-stroke or cycle internal combustion engines, comprising at its inlet an essentially frustoconical diffusor, a shell of a truncated cone immediately adjoining with its end having the greater diameter the end of the diffusor having the greater diameter, and deflector for the gas stream downstream of said shell of a truncated cone.

Abstract: A muffler construction, particularly for exhaust gases of air-operated tools, comprises, a tubular sleeve having a passage therethrough, an exhaust gas pipe connected into the sleeve and defining a restricted flow passage with the sleeve, first and second opposed cylindrical coaxial shell sections, each having a closed end wall at their respective outer ends and facing in opposite directions engaged with the exhaust gas pipe, and sidewalls spaced radially outwardly from the sleeve. The exhaust gas pipe has a gas pipe discharge and there are partition walls in the shell sections defining a first expansion chamber and at least one additional expansion chamber. A constricted flow passage is defined between the first expansion chamber and the at least one additional expansion chamber with sealing and enclosing members closing the sidewalls of the first and second shell sections so as to define the first expansion chamber and at least one additional expansion chamber within the shell sections.

Abstract: A muffler comprising: a cylindrical body closed at opposite ends with end members; an exhaust gas in-flow tube penetrating and secured to one of the end members; an exhaust gas out-flow tube penetrating and secured to the other end member; and at least one perforated partition wall member for supporting both the tubes and dividing the interior of the body; the exhaust gas in-flow tube at least having an end portion of an inner diameter smaller than the inner diameter of an exhaust tube connected to the exhaust gas in-flow tube, the end portion being closed with a porous body and communicating with one of the sections of the body interior through the porous body; the exhaust gas out-flow tube being open at opposite ends, one of the ends communicating with the other section; and at least one of the tubes being formed in the peripheral wall with a shunting hole.

Abstract: A hollow finned, multipassage, aluminum or ceramic exhaust gas cooling device is clamped between an inlet structure and an outlet structure which provide for retroverted flow and muffling. The device may be air-cooled internally.

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 internal combustion engine air cleaner assembly has a lower supporting tray wall, a top cover or enclosure wall, and a side wall, together defining a hollow air expansion chamber containing a filter element; the chamber has an air inlet and an outlet opening to the engine that lies in the plane of the lower wall, the outlet being part of an angled outlet orifice cowl asymmetrically positioned with respect to the centerline of the surrounding side and top walls and surrounding the outlet and having an inlet that is in a plane inclined to the planes of the top and side walls to reduce noise.

Abstract: A muffler for an internal combustion engine utilized on a motorcycle or the like. The muffler provides the necessary silencing action while being defined to be light in weight, small and pleasing in appearance. The exhaust gases are subdivided into a plurality of streams and successively conveyed through three silencing chambers. The gases are caused to change in direction and are shredded in each chamber for dissipating energy to provide the desired silencing action.

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: A muffler for an internal combustion engine includes a cylindrical casing having end plates closing the interior thereof. At least one baffle extending perpendicularly to the central axis of the casing is provided for dividing the interior of the casing into a front chamber and a tuning chamber. A tuning tube extending through the baffle places the front chamber into flow communication with the tuning chamber, and at least one exhaust gas inlet pipe extends into the front chamber through one of the end plates in coaxial relationship with the tuning tube. At least one exhaust gas outlet pipe is provided through the one end plate in parallel relationship with the inlet pipe. Furthermore, one or more openings are provided in the baffle in coaxial relation to the exhaust gas outlet pipe.

Abstract: An exhaust silencer comprising a primary exhaust gas expansion chamber, a secondary exhaust gas expansion chamber having a greater volume than said primary expansion chamber, an acoustically tuned length of exhaust pipe leading from the primary expansion chamber to the secondary expansion chamber and representing the only outlet from said primary expansion chamber and the only inlet to the secondary expansion chamber, an outlet pipe leading from the secondary chamber and surrounding said exhaust pipe with clearance between said pipes, and a further pipe surrounding said outlet pipe with clearance between said pipes, the outlet pipe and the said further pipe being perforated along at least part of their lengths.

Abstract: A muffler, especially for a portable internal combustion engine, particularly for driving a motor chain saw, which muffler comprises an exhaust gas receiving chamber which is defined by a chamber wall and by a pan-shaped housing wall including an inlet for the exhaust gases. Arranged on the inside surface of the chamber wall there is arranged an exhaust gas conveying passage communicating with the exhaust gas chamber and being adapted to deflect an exhaust gas current by preferably 90.degree.. This passage is adapted to convey the thus deflected exhaust gas current through an aperture in the chamber wall. Above this aperture on the outside of the chamber wall and projecting therefrom there is provided a bend from which the exhaust gas current through an outlet in the bend flows at least approximately parallel to a portion of the chamber wall.

Abstract: An improved concentric pass-type muffler construction. The muffler includes an outer generally cylindrical casing enclosed by a pair of end heads, and an inlet tube, connected to the exhaust pipe of an engine, is mounted axially on one head, while an outlet tube is mounted on the opposite head. Located centrally within the casing is an inner body having a central closure or baffle and the inlet tube communicates with the upstream end of the inner body, while the outlet tube communicates with the downstream end of the body. The upstream end of the inner body is provided with an oval configuration and the major diameter of the upstream end is secured to the inner surface of the cylindrical casing. The downstream end of the inner body is also provided with an oval configuration, with the major diameter being displaced 90.degree. from the major diameter of the upstream end of the body, and is secured to the caasing.

Abstract: Disclosed is an exhaust silencer suitable for use with portable combustion engines, and particularly for use with chain saw engines, comprising a chamber having an inlet and outlet for receiving the engine exhaust; means disposed about the chamber outlet for reducing the kinetic energy of the exhaust flowing therethrough; and an air duct means mounted exteriorly of the chamber below the chamber outlet for cooling the chamber, the kinetic energy reducing means, and the exhaust gas by contact with a stream of ambient air flowing therethrough.

Abstract: There is disclosed a muffler for an internal combustion engine, particularly an automobile engine, which includes a heavy steel outer casing formed from a section of cylindrical tubing together with an internal baffle structure of two sections of smaller diameter cylindrical steel tubing at least one of which is perforated to create a plurality of louvered openings extending along and around the tubing section. Each of the tubing sections has an end that is offset by reason of a pair of opposite-direction bends in the tubing, and the offset ends of the two sections of tubing are overlapped and joined together by welding or other suitable means to produce an extended baffle structure of approximately the same length as the outer casing. The offset ends of the sections of tubing which are joined together are preferably flattened on the sides adjacent to each other to reduce the maximum dimension of the baffle structure along the portion thereof where the two tube sections overlap.

Abstract: A muffler comprising: an upper case provided at the opposite ends with semi-cylindrical inlet and outlet sections respectively and having an outwardly raised central portion and an integral flange-like edge portion; a lower case joined at a flange-like edge portion to that of said upper case and substantially symmetrical with said upper case with respect to the underside thereof; an exhaust inlet tube forming member having at least a semi-cylindrical inlet section inserted in a cylindrical inlet formed by the inlet sections of said upper and lower cases joined together and a gutter-like guide section connected to said inlet section and being joined to said upper case, lower case or both of them, said forming member being provided adjacent to an end thereof with a perforated portion; and an exhaust outlet tube forming member having at least a semi-cylindrical outlet section fitted in a cylindrical outlet formed by the outlet sections of said upper and lower cases and a gutter-like guide section connected to sa

Abstract: An exhaust gas silencer having a casing including gas inlet and exhaust passages, a plurality of baffle plates having inner portions together defining a central chamber constituting one of said passages and extending longitudinally of the casing, and outer portions extending between the central chamber and the inner wall of the casing to direct the exhaust gas along a tortuous path, each outer portion meeting said inner wall along a line circumferentially spaced from any radius extending from the longitudinal axis of the central chamber through the juncture of the inner and outer portions.

Abstract: A muffler for automobiles having a drum-shaped expansion chamber of diameter D and length h, to which gas inlet and outlet pipes and an insert pipe of a Helmholtz resonator open so that the gas flow traverses the expansion chamber substantially diametrically therethrough, wherein the ratio h/D is substantially 0.25 - 0.4.

Abstract: Mufflers suitable for use with automobile engines include a main body closed at the forward and rear ends thereof by forward and rear end plates, an inlet pipe leading into the main body through an aperture in the forward end plate and an outlet pipe leading out of the main body through the rear end plate. Features in accordance with the present invention contributing to muffling of engine sound are a flared end on the upstream end of the outlet pipe, a porous covering of heat-resistant material over the downstream end of the inlet pipe, short-circuit holes in at least one of the pipes, a porous partition separating the interior of the main body into forward and rear chambers, and selected ratios of the lengths of the portions of the inlet and outlet pipes within the main body.

Abstract: An engine muffler which includes a chamber divided into two balanced sections, an inlet pipe that extends through a first chamber into the second, and a transfer tube for carrying exhaust gas from the second chamber to the first. A spark arrester at the exit end of the muffler includes a plurality of slightly spaced plates that permit the outflow of gas but not of large carbon particles, and a closed dish-shaped end plate for receiving the carbon particles.

Abstract: A muffler and spark arrester for use on an internal combustion engine has an outer tube extending along an axis between an inlet and an outlet. A perforate inner tube is disposed coaxially within the outer tube and merges therewith adjacent the inlet and is in effect connected thereto near the outlet by a partially toroidal end wall. Sound absorbing material is lodged between the inner and outer tubes. A plurality of nested, partially toroidal cups is disposed coaxially adjacent the end wall. A resonator-arrester chamber is coaxially nested with the toroidal cups. A central tube is held by a gas barrier wall coaxially within a portion of the inner tube. The parts are held together by an axially extending through bolt.

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: An apparatus for reducing acoustical pressure in a tubing is disclosed comprising a first molded plastic member having a first support with an orifice extending therethrough and having a first side forming a substantially saucer shaped member. A plurality of first walls are molded into the first member to extend from the first support radially spaced about the orifice and interposed between the orifice and the first side. A second molded plastic member, which is smaller than the first member, includes a second support and a second side. A plurality of second walls extend from the second support radially spaced and interposed between the center of the second support and the second side. A tubing having acoustical pressure is receivable in the orifice of the first member. The first and second members are mounted to one another forming a labyrinth passage between the orifice and the first and second sides of the first and second members.

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 muffler for attenuating sound in internal combustion engine exhaust systems comprises an inner shell subdivided into an inlet chamber and an outlet chamber, inlet and outlet tubes for the muffler opening into the respective chambers, and an outer shell surrounding the inner shell but spaced transversely from it to provide a passage between the outer periphery of the inner shell and the inner periphery of the outer shell through which gas flows toward the inlet end of the muffler from the inlet chamber to the outlet chamber.

Abstract: A fluid operated hydraulic pump of the type using air pressure to produce high pressure hydraulic fluid wherein an air pressure driven motor and a hydraulic pump are positioned in adjacent axially aligned relationship and the air motor includes a reciprocating piston which drives the hydraulic pump. The air motor includes an exhaust passage having an expansion chamber therein for receiving exhaust air flow and including a plurality of baffles therein, the expansion chamber and the baffles functioning in combination to reduce the noise generated by the air motor without the use of other muffling material thereby avoiding undue back pressure in the air motor and increasing the speed and efficiency and operation of the air motor and the pump.

Abstract: The pressure in a high-pressure steam boiler or other pressure fluid tank is occasionally relieved by means of a discharge device having a pressure-relief valve mounted on an ejection conduit opening into a hood connected to a discharge conduit. A break in continuity is provided between this ejection conduit and this hood in order to allow relative movements thereof under thermal expansion; furthermore the ejection conduit opens into the hood through a generally transversely directed nozzle system so that the jet issuing therefrom has a zero or negligible axial velocity component.

Abstract: A refrigerant compressor including discharge gas muffling means formed within the outer housing means by first and second wall means which cooperate with the bottom of the outer housing means to provide first and second chambers. The first chamber is connected by an inlet port to the compression mechanism for receiving discharge gas therefrom and a discharge port is provided from the second chamber to communicate the discharge gas to the discharge line of a refrigeration system. Divider walls within the first and second chambers are provided with restricted openings so as to provide restriction passages and expansion chamber muffling regions within the first and second chambers to effectively muffle noises emanating from the discharge gas passing from the compression mechanism to the discharge line outside of the compressor.

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.