Abstract: A muffler for equipment powered by compressed air, the muffler comprising a flexible muffler body formed from a sufficiently resilient material to resiliently deform under the influence of an exhaust air stream from an air motor, the body having an inlet and an outlet; a plurality of flexible baffles located within said body to muffle the sound of the air powered equipment; and an oil mist remover extending at least partially through said body, said oil mist remover being sized and shaped to prevent trapped oil from being re-misted by said exhaust air stream.

Abstract: An exhaust muffler with a single-wall shell having a first end and a second end features a plurality of embossments formed on the shell and extending from the first end of the muffler to the second end of the muffler. The embossments are arranged in a pattern such that any straight line extending from the first end to the second end intersects at least one of the embossments, thereby imparting increased stiffness to the muffler shell. Each of the embossments preferably have an elliptical shape and are arranged in rows extending substantially parallel to a longitudinal axis of the muffler. The embossments in any given row are rotated ninety degrees from the embossments in preceding and succeeding rows and are spaced to provide an interlocking pattern.

Abstract: An improved exhaust system for an internal combustion engine generally comprises two expanding megaphones, separated by a dual core annular flow silencing section. The two or split megaphone design facilitates broadening of the time of the negative pressure wave to provide a desirable broad range power output while substantially reducing obnoxious sound output.

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 fluid guideline with at least two structural elements made of substantially soundproof material has at least one opening for sound damping. An impedance change (in particular in the form of an impedance discontinuity) of the flow resistance of the fluid flowing through the fluid guideline is present between two adjacent structural elements, and the at least one opening is arranged in the region of the impedance change between two adjacent structural elements.

Abstract: An absorptive and reactive muffler includes an annular flow path for the gas with the center of the annulus having a plurality of resonators which are in open communication with the downstream end of the annular flow path and make up the reactive portion of the muffler. The flow path is at least partially lined by an absorptive material overlain by a perforate material and makes up the absorptive portion of the muffler.

Abstract: An exhaust muffler with a single-wall shell having a first end and a second end features a plurality of embossments formed on the shell and extending from the first end of the muffler to the second end of the muffler. The embossments are arranged in a pattern such that any straight line extending from the first end to the second end intersects at least one of the embossments, thereby imparting increased stiffness to the muffler shell. Each of the embossments preferably have an elliptical shape and are arranged in rows extending substantially parallel to a longitudinal axis of the muffler. The embossments in any given row are rotated ninety degrees from the embossments in preceding and succeeding rows and are spaced to provide an interlocking pattern.

Abstract: Disclosed is a diffuser apparatus for facilitating a reduction in fluid pressure and suppression of noise. The apparatus comprises a tubular inner sleeve, a tubular muffler and a tubular outer sleeve. The inner sleeve defines a fluid flow axis and has a plurality of inner sleeve passages. The outer sleeve has the inner sleeve concentrically positioned therein and defines a plurality of outer sleeve passages. The muffler is concentrically positioned between the inner and outer sleeves such that fluid flows radially outwardly through the inner sleeve passages, through the muffler, and through the outer sleeve passages. The muffler may be spaced from the inner sleeve so as to define a gap between the muffler and the inner sleeve. The muffler may also be spaced from the outer sleeve so as to define a gap between the muffler and the outer sleeve.

Abstract: A reactive silencer intended for industrial supply air or exhaust air channels has a sound attenuator chamber (10), to which is fitted a partition wall (12) dividing the sound attenuator chamber into a first and second chamber part (14, 16). The partition wall (12) is fitted with two or more channels or pipes (26, 26′, 26″) which connect the first chamber part (14) to the second chamber part (16). In this way a silencer of small size and simple structure is obtained for attenuating noise, especially that produced by large or several small air channels.

Abstract: An acoustic muffler for a turbine engine exhaust comprises an outer shell of tubular configuration, a tubular liner disposed within the shell, and a plurality of dividing walls extending between the liner and the outer shell so as to divide the generally annular space between the liner and shell into a plurality of chambers circumferentially spaced about the muffler. A central longitudinal axis of the liner is radially offset from the central longitudinal axis of the shell such that the chambers have different depths in a radial direction of the muffler, and the liner has at least one opening into each chamber. Thus, the muffler has a plurality of chambers of different sizes providing noise attenuation at a plurality of specific tuned frequencies, and the liner provides broad band attenuation.

Abstract: An air resonator for an air intake system includes a plurality of serially positioned increasing volume chambers. Air passing to the engine passes through these chambers. Noise passing from the engine back towards the source of air will also pass through these increasing volume chambers. As the noise serially passes through the increasing and then decreasing volume, the noise is dissipated.

Abstract: The present invention provides a muffler which has an outlet tube with a funnel shaped element having a large diameter end positioned in an expansion chamber and conically tapering to a junction with a cylindrical neck element extending into an inlet end of an outlet tube. An inlet tube is supported by an outer shell which also supports the outlet tube. The inlet tube is attached to the outer shell by a first partition and a first end cap, forming a tuning chamber. The outlet tube is attached to the outer shell by the funnel shaped element and a second end cap, forming an outlet chamber. A space defined by the distance between the first partition and the second partition and the geometry of the outer shell forms an expansion chamber. The three different chambers serve to either tune or quiet the exhaust coming from an internal combustion engine, and the funnel shaped element serves to smooth the flow of exhaust from the inlet tube to the outlet tube.

Abstract: Pipe section running along a curve, intended for use in a muffler, comprising two hollow-formed molded parts which are mirror-symmetrical in relation to the radial plane of the curve and which have connected thereto a flat outside edge running in the radial plane along the outside of the curve, which flat outside edges are placed on each other so that the molded parts together form the pipe section, a third flat part being placed at the position of the radial plane between the two molded parts in such a way that a curved edge of said third flat part is situated between the two flat outside edges of the molded parts and is fastened to said outside edges.

Abstract: A noise suppressor for a displacement-type compressor, in particular in an engine installation with such a compressor connected in series with a turbocharger. The noise suppressor comprises a nozzle (31). The inlet of the nozzle is connected to the outlet of the compressor. The compressor's outlet merges into an expansion chamber (32) with a largest diameter ("d") greater than the largest inlet diameter ("e") of the nozzle. The chamber has an outlet formed by a second nozzle (33) identical to the first nozzle.

Abstract: A method and apparatus for manufacturing a hose for a vacuum cleaner, such hose having anti-whistling characteristics. In a standard blow molding process, a blow pipe is configured with a plurality of printing rollers having arcuate outer surfaces configured and spaced in such a manner as to assure engagement of the entirety of the hose with a printing roller during the manufacturing process. The printing rollers are provided with apertures which, upon engagement with the tacky material of the inner surface of inwardly extending corrugations causes indentations or protrusions in such surface. The roughened interior surface prevents the formation of audible harmonics when air passes through the tube response to a vacuum source at one end thereof.

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 invention concerns a reactive sound attenuator for air-conditioning ducts, in particular for air ducts in paper mills. The sound attenuator includes at least two chambers separated from another by means of a partition wall. The partition wall is provided with an opening or with a tube placed in the direction of flow of the air flowing through the sound attenuator, the air flowing through said opening or tube out of one chamber into the other. The main plane of the partition wall is at an acute angle in relation to the direction of air flow through the sound attenuator. Preferably, the partition wall is at an angle .alpha. from about 40.degree. to about 70.degree. in relation to the direction of air flow through the sound attention.

Abstract: A muffler for an internal combustion engine or the like having improved attenuation, minimal back pressure and minimal effect to column inertia through the muffler. The muffler comprises an outer housing and a first perforated tube insert extending from one end of the housing and terminating within the muffler. In another embodiment the perforated first tube includes a second tube insert abutting the distal end of the first tube in a continuous flow relationship therewith. The second tube has a smaller diameter than the first tube and includes at least one enlarged portion between its ends. Other embodiments are shown that include a combination of either the first and second tubes alone, a second tube with a plurality of enlarged portions between its ends, different sized enlarged portions between the ends of the second tube, various configured enlarged portions and at least two different sized perforations through the perforated tubes. A bracket is shown for attaching the tubes within the housing.

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: Attachment means for connecting an insulated pipe to an element, such as the manifold, in the exhaust system of a vehicle. The attachment means includes a conduit which extends into the end of the insulated pipe. A transverse lug or a helical flange on the conduit engages the spiral corrugations of the inner diameter of the pipe to allow the conduit to be threaded into the pipe. The end of the pipe is received in an end cap slidably mounted on the conduit. When the cap hits a stop on the conduit during threading of the conduit into the pipe the lug or helical flange pulls the pipe against the cap, tightening the connection to the pipe.

Abstract: A straight through type muffler for generating an exhaust flow from an internal combustion engine includes a closed expansion chamber in communication with the straight through passage of the muffler. A minority of the gases passing through the straight through passage will be accumulated in the expansion chamber and will be returned to the straight through passage when the pressure of the gases passing through the straight through passage is reduced, thereby minimizing the back pressure from the muffler.

Abstract: A silencer comprising a cylindrical casing assembled from two half-cylindrical shell members is produced by placing in one of the shell members a row of modular channel blocks and then completing the silencer by mounting the other shell member over the row of blocks. The modular blocks are selected from a multi store holding groups of blocks of generally uniform outer shapes, but prefabricated with mutually different inner shapes such that the different blocks, each one or each pair thereof, show specific characteristics with respect to the throttling and/or sound damping capacity, whereby effective silencers for different engines are easy and cheap to manufacture, even with the use of non-corroding materials.

Abstract: In order to reduce static and dynamic pressures in pipelines or tubes and, in particular, in order to attenuate the transmission of sound through tubes in a longitudinal direction it is proposed to provide an outer member and/or an inner member of the tube in such a way as to afford elastic yieldability. Such an elastically yieldable outer member may, for example, be constituted by a low-wave, soft, radially breathing compensator or a corrugated tube. An elastically yieldable inner member may, for example, be constituted by an imperforate breathing body disposed within the tube.

Abstract: A combined gear cover and mount for an internal combustion engine is disclosed for use on an engine having a vibration damper mounted on a projecting end of the engine crankshaft wherein the gear cover includes a housing for enclosing the vibration damper while re-enforcing the engine mount formed integrally with the gear cover. The gear cover is adapted to connect with a gear plate mounted directly on the engine block to form an enclosure for the gear train of the engine. The gear cover also includes an integral fan clutch housing and a lubrication fluid transfer passage for an engine driven air compressor.

Abstract: A method and apparatus for suppressing internally generated gas turbine engine low frequency noise is disclosed. The apparatus is comprised of means for structuring the cross-sectional area of the gas flow path into one or more open elements of a predetermined size. The method involves a way of determining the size of each of the elements and the total number of elements.

Abstract: A muffler apparatus has an outer housing for being attached to a motorcycle or the like. Disposed internally of the housing is a passageway assembly having a connecting tube with a flare for being connected to an exhaust pipe and a perforated tube connected to the connecting tube. A solid tube, opened at both of its ends, is rigidly affixed to the interior of the perforated tube in concentric relationship. The solid tube extends through at least a portion of the length of the perforated tube. Alternatively, several solid tubes in either clustered or concentric arrangements may be used in place of the single solid tube.

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: A low noise level, pressure fluid spouting device includes an inlet for introducing a pressure fluid therein at one end thereof; a nozzle connected to the inlet for jetting or emitting the pressure fluid therefrom, the nozzle having an annular inner wall of a predetermined diameter as a nozzle port thereof with an enlarged portion at the other end thereof for spouting the pressure fluid from the nozzle. The enlarged portion has a predetermined length (1.sub.o) from the entrance to the exit or open end thereof, and comprises an annular inner wall of a predetermined diameter (d.sub.2) larger than that of the nozzle means as an enlarged passage communicating with the nozzle port; and an outer wall which is tapered or gradually decreased in width towards the exit or open end portion of the enlarged portion with a predetermined angle of inclination (.theta.). The wall of the enlarged portion has a predetermined thickness (t) at the exit or open end portion of the enlarged portion.

Abstract: A silencer device for attenuating fluid borne noise has a flow through housing with an open upstream end for the entrance of a fluid into the housing and a coaxial open downstream end for exhausting the fluid from the housing. An entrance header formed of a plurality of spaced apart intersecting elongated members defining a plurality of rectangular entrance apertures, each elongated member having a V-shaped transverse cross-section shape and oriented with its apex pointed in an upstream direction, is coextensively disposed over the upstream open end. An exhaust header also formed of a plurality of spaced apart intersecting elongated members defining a plurality of rectangular exhaust apertures, each elongated member having a V-shaped transverse cross-section shape and oriented with its apex pointed in a downstream direction, is coextensively disposed over the downstream open end.

Abstract: A noise silencer for an internal combustion engine has a hollow pipe serving as an air intake for the internal combustion engine and having a length L which is an even submultiple of the wavelength at the lowest of a range of noise frequencies from the internal combustion engine which are to be attenuated. The hollow pipe attenuates noise at the lowest frequency and at certain other frequencies throughout the range. Intervening frequencies are attenuated by at least one expansion chamber coupled to the pipe and having extended inlets and outlets the lengths of which are even submultiples of L. In certain preferred arrangements of the silencer the hollow pipe extends into one expansion chamber forming an extended outlet, a second hollow pipe extends between and within the expansion chamber and a second expansion chamber forming an extended inlet and an extended outlet and a third hollow pipe extends into the second expansion chamber from the internal combustion engine to form an extended inlet.