Abstract: A muffler for a vehicle includes a plurality of baffles fixed at a predetermined distance in a longitudinal direction of a muffler housing, an exhaust gas inflow pipe, an intermediate pipe, and a plurality of exhaust gas outflow pipes having an inlet thereof positioned in the same chamber defined by the adjacent pair of the baffles with the outlet of the intermediate pipe to considerably reduce exhaust noise, flow-induced noise, and booming noise of exhaust gas. The muffler is effectively protected from thermal damage of a vehicle by implementing a sound-absorbing heat-insulating material therein, and impresses consumers with dynamic, powerful, and polished image by making the exhaust gas outflow pipe in a dual type composed of first and second exhaust gas outflow pipes and disposing the outlet at the lower center of a rear bumper to be exposed to the outside, thereby considerably improving productivity of vehicles.

Abstract: A vehicle exhaust component includes an outer shell defining an internal cavity and at least one internal pipe located within the internal cavity. A wire tube surrounds the internal pipe and is spaced apart from the pipe by a radial gap. This radial gap is filled with a fiber material.

Abstract: A muffler for a vehicle may include a plurality of baffles to form a plurality of chambers, an exhaust gas inflow pipe having an outlet connected to one of the chambers inside the muffler housing through the baffles, an intermediate pipe disposed in parallel with the exhaust gas inflow pipe in the muffler housing through the baffles to fluid connect at least two chambers and a plurality of exhaust gas outflow pipes having an inlet positioned with an outlet of the intermediate pipe in any one chamber divided by the baffles and an outlet protruding outward through the muffler housing, without passing through the baffles, such that the exhaust gas passing through the intermediated pipe may be discharged outside the muffler housing.

Abstract: An absorptive muffler assembly includes a first body and a second body surrounding the first body. A resilient mount having at least one resilient portion and at least one support arm supports the first body and isolates the second body from vibrations of the first body.

Abstract: In a muffler which includes an outer tube which configures an outer wall, an inner tube provided in the outer tube and having punching holes formed therein, and a sound absorbing material filled between the outer tube and the inner tube, and which is attached to an exhaust pipe for exhausting exhaust gas from an engine, the number of punching holes at portions of the inner tube which have a great length to the outer tube is set greater than the number of punching holes at portions of the inner tube which have a small length to the outer tube in comparison with the portions having the great length.

Abstract: An exhaust system for a motorcycle is configured to enhance output while maintaining a necessary noise level. The exhaust system includes an exhaust pipe connected to an engine, and a silencer connected to the exhaust pipe. The silencer includes a hermetically sealed outer cylinder and an inner cylinder disposed within the outer cylinder so as to extend along an axis of the outer cylinder. The outer cylinder has a front end portion connected to the exhaust pipe and a rear end portion opened toward the atmosphere. The inner cylinder includes a reduced diameter portion with a diameter which becomes smaller in the downstream direction, a throttle portion with a constant diameter, the throttle portion being connected to the reduced diameter portion, and an enlarged diameter portion connected to the throttle portion with a diameter which becomes larger in the downstream direction.

Abstract: The invention concerns an external gear hydraulic pump including a pump body housing rotating pinions that mutually engage. Located on opposite sides of the body are a cover and a support, forming an outlet manifold for high pressure fluid. Acoustic insulation elements damp the vibrations produced by the pinions. The acoustic insulation elements acoustically decouple the pump body from the support.

Abstract: The object of the present invention is to provide an intake duct having waterproof function without increasing parts count. An intake duct 10 for air intake from the outside to an internal combustion engine E includes a duct wall 11 made of a resin in a tubular form. The duct wall 11 includes a waterproof and humidity-transparent component 20 having a water-repellent layer 21 made of high-density fiber and a waterproof and humidity-transparent layer 22 made of fine porous film laminated to each other.

Abstract: An attenuation device, particularly a pulsation attenuator, has a casing (1) defining a fluid chamber (11) through which a fluid may flow along a flow axis (7), and has an attenuation element made of a resilient material located within the casing (1). The attenuation element has at least two annular bodies (15, 17) that are disposed in an at least partially overlapping manner, surrounding the flow axis (7) at least partially.

Abstract: A noise elimination method based on sound ray refraction theory and the muffler thereby are disclosed. The method use s low temperature refrigeration system (2) to form a temperature gradient inside and outside the chamber of the muffler, and the temperature inside the pipe wall of the chamber is higher than the outside. The temperature gradient may force sound ray to reflect towards the low temperature direction, so the noise of the system may be captured and reduced. The muffler comprises a housing (1) whose inner wall is laid with a sound absorbing structure (4), and on the outer wall of the housing (1) is provide a low temperature refrigerating system (2). The system covers at least of the area of the outer wail of muffler housing (1) and combines with a temperature control system (3) to realize quantitative control of the temperature gradient. The muffler improves the noise-absorbing effect of the existing muffler effectively.

Abstract: A method and apparatus for providing a loudspeaker assembly is provided. In accordance with at least one embodiment, a method is provided for mounting a loudspeaker driver in a loudspeaker driver aperture defined in a ground plane and installing a grille in relation to the ground plane such that a distance between the grille and the ground plane decreases as the distance from the loudspeaker driver increases. In accordance with at least one embodiment, apparatus is provided comprising a ground plane, a loudspeaker driver mounted in a loudspeaker driver aperture of the ground plane, and a grille positioned relative to the ground plane such that a distance between the grille and the ground plane decreases with increasing distance from the loudspeaker driver.

Abstract: A silencer for a motorcycle has a front cup which has a tapered tubular shape, a center sleeve which is connected to the front cup, and a tail cup which is connected to the center sleeve. Since the front cup has a tapered tubular shape, the front cup is arranged such that a front end of the front cup is positioned in the vicinity of a main frame. A distal end of the silencer can be shifted frontward in the longitudinal direction of a vehicle compared to a silencer of a prior art. As a result, a length of the silencer can be increased while avoiding interference between the silencer and legs of a rider and hence, silencing performance of the silencer can be enhanced. Since the distal end of the silencer can be shifted frontward in the longitudinal direction of the vehicle, the concentration of a mass can be acquired.

Abstract: A silencer capable of preventing a damage of a metallic layer formed on an inner surface of an external cylinder formed from CFRP, and the external cylinder for the silencer. The silencer 1 includes the external cylinder 2, an internal cylinder 3 and an acoustic absorbent (not shown). A posterior end 2r of the external cylinder 2 is detachably provided with a tail cap 4. An anterior end 2f of the external cylinder 2 is detachably provided with a coupling body 5. An inner circumferential surface of the posterior end 2r of the external cylinder 2 includes a posterior covering portion 30 while an inner circumferential surface of the anterior end 2f thereof includes an anterior covering portion 32. This posterior covering portion 30 covers a posterior end portion 8r of a metallic layer 8 while the anterior covering portion 32 covers an anterior end portion 8f thereof.

Abstract: The present invention relates to a coolant circuit of a cooling system including a pipe-shaped body defining a cavity. It has a sound absorber defining a flow channel and at least one resonator chamber which is connected to the flow channel via a connection channel. The sound absorber is an insert in the cavity of the pipe-shaped body, which forms the flow channel, the at least one resonator chamber, and the at least one connection channel.

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: An inlet silencer for an air inlet in a housing, which housing contains a source of high frequency noise radiated by an air intake for the source of high frequency noise, comprises: a plenum that extends longitudinally within the housing that couples the air inlet in an upstream region of the plenum to the air intake for the source of high frequency noise in a downstream region of the plenum; a partition that extends laterally within the plenum between the upstream region of the plenum and the downstream region of the plenum; at least one channel that penetrates longitudinally through the partition that has a gap across its inner surface that approximates one wavelength of at least one fundamental frequency of high frequency noise that the source of high frequency noise generates; and acoustic damping material that lines the inner surface of the channel.

Abstract: A vehicular muffler is configured and arranged to smoothly introduce exhaust gas into a sound-absorbing material disposed inside of an outer case which has a plurality of relatively short inner sleeves therein. The muffler includes a porous plate which is disposed inside of the outer case, and which is connected to an exhaust pipe, and the porous plate is operatively connected to an outlet pipe which discharges an exhaust gas to the outside environment through an opening formed in an outlet side of the outer case. In one embodiment, the inner sleeves are arranged substantially parallel to each other, and are fluidly connected to a joint exhaust feed pipe disposed inside the outer case. The inner sleeves are connected to the outlet pipe on the outlet side of the outer case.

Abstract: A composite structure and an associated exhaust washed structure are provided which may be formed of ceramic matrix composite (CMC) materials. A method of fabricating a composite structure which may include the CMC material is also provided. A composite structure may include a corrugated septum extending in a lengthwise direction. The composite structure may also include a flute within which the corrugated septum is disposed to form, for example, a partitioned flute assembly.

Abstract: According to the invention, at least part of the edge of the hole is loosely surrounded with a mesh structure so as to create a space between the latter and said edge part.

Abstract: A noise damper for a compressed air device includes a tubular housing part provided with an air inlet and an inserted insulating material, in particular, an inserted knitted fabric roll. The air inlet is embodied in the envelope of the tubular housing part such that the supplied air tangentially flows through the insulating material or the knitted fabric roll, is radially deviated inside the tubular housing part, and axially flows out from at least one end of the tubular housing part.

Abstract: An exhaust system includes a tubular inner shell for passing therethrough exhaust gases from a combustion engine, and a tubular outer shell enclosing the tubular inner shell and cooperating therewith to define a sound silencing chamber into which the exhaust gases are introduced. The tubular inner shell forms an inner peripheral wall of the sound silencing chamber, and an upstream portion of the inner peripheral wall is formed with a perforated wall area having a plurality of communicating perforations for communicating between an interior of the tubular inner shell and the sound silencing chamber, and a downstream portion of the inner peripheral wall has a non-perforated wall area having no communicating perforation defined therein.

Abstract: An exhaust system for a straddle-type vehicle, such as a motorcycle, which achieves miniaturization and also provides a reduced noise output. The exhaust system is connectable to an engine of an associated vehicle and includes an exhaust pipe and a silencer. The silencer comprises an outer housing and an inner core accommodated in the outer housing. A sound absorbing material is arranged on an outer surface of a side wall of the inner core in a manner to come into close contact therewith. An air space is provided between an outer surface of the sound absorbing material and an inner surface of the outer housing.

Abstract: An exhaust device for a straddle type vehicle allowing a compact design while still satisfying the sound deadening characteristic requirements is provided. The exhaust device for a straddle type vehicle comprising: an exhaust pipe that is connected to an engine; a silencer that is connected to the exhaust pipe wherein the exhaust pipe is provided with a Helmholtz resonator, and the Helmholtz resonator is filled with a sound absorbing material. The Helmholtz resonator is formed with an opening that communicates with the inside of the exhaust pipe. The opening is formed in a place where the sound pressure in the exhaust pipe is high during the operation of the engine.

Abstract: In a muffler which includes an outer tube which configures an outer wall, an inner tube provided in the outer tube and having punching holes formed therein, and a sound absorbing material filled between the outer tube and the inner tube, and which is attached to an exhaust pipe for exhausting exhaust gas from an engine, the number of punching holes at portions of the inner tube which have a great length to the outer tube is set greater than the number of punching holes at portions of the inner tube which have a small length to the outer tube in comparison with the portions having the great length.

Abstract: An exhaust device for a straddle-type vehicle that satisfies the requirements of sound deadening characteristics and which has a reduced size is provided. The exhaust device for a straddle-type vehicle that includes an exhaust pipe connected to an engine and a silencer connected to the exhaust pipe. The silencer includes at least one resonator selected from a group consisting of a Helmholtz resonator and a side branch resonator. The resonator is packed with a sound absorbing material.

Abstract: The present invention provides composite muffler systems formed of a long fiber thermoplastic. Long fiber thermoplastic technology allows the fibers, to maintain a length sufficient to provide structural strength at lower fiber loading. The long fiber thermoplastic material for forming composite muffler systems also provides increased impact strength and creep resistance as well as chemical and thermal resistance. Mufflers molded with long fiber thermoplastics demonstrate improved dimensional stability as compared to known short fiber based moldings. One suitable muffler structure is a multi-piece muffler assembly including at least one long fiber thermoplastic shell section. In accordance with the present invention, the long fiber thermoplastic material and moldings may also be combined with over-molding of preforms of unidirectional or woven inlays, which provide local structural performance.

Abstract: The present invention relates to a muffler facia assembly including a muffler with at least one thermoplastic shell formed into a facia assembly on a motor vehicle. The facia may be any suitable body part of a motor vehicle, such as a bumper, a rocker panel, an air dam, a spoiler, a sideboard or a body module. An assembly in accordance with the present invention includes structural members to provide crash management features to increase the strength and impact resistance. In accordance with the present invention, the long fiber thermoplastic material and moldings may also be combined with over-molding of preforms of unidirectional or woven inlays, which provide local structural performance. The use of such preforms is particularly suited to use in the manufacture of high temperature, structural articles such as bumper muffler combinations.

Abstract: A muffler for an internal combustion engine exhaust system includes a housing having an inlet and outlet headers enclosing opposite ends of an outer shell. A partition divides a housing interior into first and second chambers, the first chamber having sound absorbing material positioned therein. The partition has an aperture allowing fluid communication between the first and second chambers. A through pipe extends through the inlet and outlet headers and the partition and has a plurality of perforations enabling fluid communication between the through pipe and the first chamber. A valve assembly has a valve flap positioned inside the through pipe for rotation with an axle pivotally coupled to the pipe between a closed position and an open position. The valve is positioned downstream of the pipe perforations such that all of an exhaust gas flowing through the muffler passes through the valve regardless of the valve flap position.

Abstract: The insert for an engine exhaust system has at least one conical section of flexible mesh or rovings of metallic or other high temperature resistant fiber or tape. Each section includes a rigid anchor or attachment ring having an outer diameter closely conforming to the inner diameter of the exhaust pipe, with the anchor ring being welded to the mesh or roving or tape material or the mesh or roving or tape being crimped between two concentric rings. A smaller diameter support ring may be provided at the opposite end of the conical mesh, with the support ring braced by a series of radial arms. The device may serve to reduce the sound output of the exhaust system, and/or may serve as a spark arrestor as well.

Abstract: A silencer capable of preventing a damage of a metallic layer formed on an inner surface of an external cylinder formed from CFRP, and the external cylinder for the silencer. The silencer 1 includes the external cylinder 2, an internal cylinder 3 and an acoustic absorbent (not shown). A posterior end 2r of the external cylinder 2 is detachably provided with a tail cap 4. An anterior end 2f of the external cylinder 2 is detachably provided with a coupling body 5. An inner circumferential surface of the posterior end 2r of the external cylinder 2 includes a posterior covering portion 30 while an inner circumferential surface of the anterior end 2f thereof includes an anterior covering portion 32. This posterior covering portion 30 covers a posterior end portion 8r of a metallic layer 8 while the anterior covering portion 32 covers an anterior end portion 8f thereof.

Abstract: Provided is a sub-muffler which needs no heat resistant material such as SUS, and which can keep its durability and sound absorbing performance even when the sub-muffler is exposed to various corrosive components in the exhaust gas. At the same time, accomplished is a low-cost manufacture, which is a challenge that sub-mufflers and sound absorbing materials commonly face. Disclosed is a sub-muffler in which a perforated exhaust pipe is arranged, and caps and an out pipe are arranged outside the perforated pipe. Sound absorbing materials are filled in the space between the perforated exhaust pipe, and the caps and the out pipe. The sub-muffler is characterized in that, among the sound absorbing materials, at least part of the sound absorbing material of the perforated pipe side is a basalt fiber for high temperature.

Abstract: A delivery pipe includes an outer pipe, an inner pipe, and a noise emission decreasing device. The outer pipe is connected to a plurality of fuel injectors. The inner pipe is disposed in the outer pipe and has an open end through which an interior of the inner pipe communicates with atmosphere. The noise emission decreasing device acts so as to decrease a noise emitted from the inner pipe. The noise emission decreasing device includes a mesh, a porous member, a vibration suppressing member provided to the inner pipe, an elastic tube fitted into the inner pipe, or a wire harness inserted into the inner pipe.

Abstract: One embodiment of the invention includes a product including a fuel-cell exhaust diffuser; an air funnel; and at least two exhaust tubes attached to the diffuser.

Abstract: A vehicle exhaust component provides comparable fully packed noise reduction capability without requiring a fully packed configuration. A pack is mounted within an internal cavity defined by an exhaust component body. A plurality of pack positions are defined within the internal cavity and at least one pack is positioned at a desired pack position to provide a desired noise reduction.

Abstract: An exhaust silencer of a combustion engine, comprising a housing (1) that is to be connected to an exhaust pipe, through which housing the exhaust gases are arranged to be conducted and which comprises a reactive part (2) and an absorbing part (3) in the flow direction of the exhaust gases. The reactive part (2) is mainly hollow and comprises, at the inlet thereof, a first exhaust pipe (5) for feeding the exhaust gases to the reactive part (2) and, at its outlet, a second exhaust pipe (6) for directing the exhaust gases from the reactive part (2) to the absorbing part (3), both exhaust pipes (5, 6) being arranged so as to essentially extend inside the reactive part (2) of the housing. The absorbing part (3) comprises an absorbing filling element (7), which essentially fills the absorbing part (3) of the housing and, at the inlet of the absorbing part (3), is shaped so as to direct the exhaust gases to the space (8) between the filling element (7) and the inner lining of the housing (1).

Abstract: A method and apparatus for providing a loudspeaker assembly is provided. In accordance with at least one embodiment, a method is provided which comprises forming a loudspeaker frame so as to define a driver housing portion, a horn portion, and a conformal portion. A driver aperture is defined for the driver housing portion, and a port aperture is defined for the horn portion. A driver is attached to the loudspeaker frame proximate to the driver aperture. A rear baffle is applied to a first conformal portion surface of the conformal portion of the loudspeaker frame. The rear baffle defines a horn cavity wall of a horn cavity of the horn portion. The horn cavity has an increasing cross sectional area as the distance from the driver housing portion increases. A grille is applied to a second conformal portion surface of the conformal portion of the loudspeaker frame.

Abstract: An air conditioning system, comprising: a channel to carry a flow of refrigerant, and a first noise reducer to change at least one property of the refrigerant as the refrigerant flows through the channel.

Abstract: A muffler assembly includes a housing defining at least one internal chamber. The housing is constructed from a composite material made from a thermoplastic resin and a reinforcing element. The reinforcing element is selected from a group of reinforcing materials consisting of glass fibers, aramid fibers, polyamide fibers, carbon fibers, graphite fibers, mineral fibers, ceramic fibers, carbon nanotubes, nano fillers, mineral fillers, ceramic fillers and combinations thereof. A pipe is received in the housing. The pipe includes at least one opening providing acoustic communication between an internal passage in the pipe and the chamber in the housing. An acoustic attenuating material is received in that chamber.

Abstract: An absorption muffler includes a metallic exhaust pipe including a plurality of perforations, a polymeric housing carried by the exhaust pipe and enclosing the plurality of perforations, and including axially opposed ends. Thermal insulation is carried radially between the exhaust pipe and the polymeric housing and axially between the axially opposed ends inclusive thereof. Acoustic insulation is carried between the thermal insulation and the polymeric housing.

Abstract: An absorptive muffler assembly includes a first body and a second body surrounding the first body. A resilient mount having at least one resilient portion and at least one support arm supports the first body and isolates the second body from vibrations of the first body.

Abstract: An apparatus and method for attenuating the sound generated by a single duct terminal unit in an HVAC (heating, ventilating, and air conditioning) system. The apparatus utilizes internal geometry to minimize noise due to air disturbances and aerodynamic effects within the apparatus.

Abstract: A silencer for a CPAP device comprises a housing assembly defining a flow path passing therethrough and including at least one of an inlet chamber, an acoustic chamber and a blower chamber. Each of the chambers has an inlet and an outlet for fluid communication therebetween. The silencer includes a combination of reactive components, resonators and dissipative elements disposed within the inlet, acoustic and blower chambers. The reactive component may be configured as a compliant-walled reactive tube. The resonator may be configured as a perforated plate defining a cavity volume. The dissipative element may comprise porous material substantially occupying the cavity volume bounded by the perforated plate in the chamber walls.

Abstract: A vehicular muffler is configured and arranged to smoothly introduce exhaust gas into a sound-absorbing material disposed inside of an outer case which has a plurality of relatively short inner sleeves therein. The muffler includes a porous plate which is disposed inside of the outer case, and which is connected to an exhaust pipe, and the porous plate is operatively connected to an outlet pipe which discharges an exhaust gas to the outside environment through an opening formed in an outlet side of the outer case. In one embodiment, the inner sleeves are arranged substantially parallel to each other, and are fluidly connected to a joint exhaust feed pipe disposed inside the outer case. The inner sleeves are connected to the outlet pipe on the outlet side of the outer case.

Abstract: A motorcycle having a tail pipe formed from a pair of branch pipes that branch from a main pipe and that ensures a sound absorbing effect. A muffler has a casing that surrounds a rear section of an exhaust pipe, and a sound absorbing material that is filled between the casing and the rear section of the exhaust pipe. The rear section of the exhaust pipe includes a main pipe that is connected to the exhaust pipe and that extends to the rear, and first and second branch pipes that are connected to and branch from the main pipe and extend to the rear. A cross sectional area of the casing, when viewed from an exhaust gas flow direction becomes larger as the casing extends toward the branch pipe side.

Abstract: A filter assembly for use with compressor assemblies such as oxygen concentrators, ventilators and other breathing apparatus including a compartmented housing member having at least one inlet opening, an outlet opening, a filter member, and an adjustment member associated with the at least one outlet opening for varying the size of the at least one outlet opening for adjusting the amount of ambient air entering the filter assembly.

Abstract: A noise eliminator for a fuel cell, where an outer shell has a reception section in which a sound absorption material is placed between the outer shell and an inner pipe and has a water discharge section that is positioned so as to face a lower portion in the vertical direction of the inner pipe and in which the sound absorption material is not placed between the outer shell and the inner pipe. The water discharge section receives water flowing into the outer shell and allows the water to flow to the outside of the outer shell. Although the water discharge section receives water flowing into the outer shell, the sound absorption material inside the noise eliminator does not absorb the water from the water discharge section and does not contain it because there is no sound absorption material in the water discharge section.

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 muffler structure capable of suppressing generation of abnormal noise in the muffler even when the outer and the inner tubes expand thermally. Provided is a double-pipe muffler structure including an inner tube and an outer tube. In the muffler structure, an annular front step portion and an annular rear step portion are formed in the inner tube, while the step portions is brought into contact, from inside, with the outer tube and thus are supported by the outer tube. The outer tube supports the front and the rear step portions by being brought into close contact with the step portions partially and elastically.

Abstract: The present invention provides composite muffler systems formed of a long fiber thermoplastic. Long fiber thermoplastic technology allows the fibers, to maintain a length sufficient to provide structural strength at lower fiber loading. The long fiber thermoplastic material for forming composite muffler systems also provides increased impact strength and creep resistance as well as chemical and thermal resistance. Mufflers molded with long fiber thermoplastics demonstrate improved dimensional stability as compared to known short fiber based moldings. One suitable muffler structure is a multi-piece muffler assembly including at least one long fiber thermoplastic shell section. In accordance with the present invention, the long fiber thermoplastic material and moldings may also be combined with over-molding of preforms of unidirectional or woven inlays, which provide local structural performance.

Abstract: A method of forming a sheet member includes feeding first raw slurry into a forming device, dehydrating the first raw slurry to form a first forming body, feeding second raw slurry including inorganic fibers having a minimum diameter substantially equal to or less than 3 micrometers on the dehydrated first slurry, dehydrating the second raw slurry to form a second forming body on the first forming body, feeding third raw slurry into the forming device, dehydrating the third raw slurry to form a third forming body on the first and the second forming bodies, and compressing and dehydrating a forming body having a three-layer structure where the third forming body is formed on the first and the second forming bodies to form a sheet member having a three-layer structure. The first and third raw slurries include inorganic fibers having a minimum diameter substantially greater than 3 micrometers.