JP6465695B2 - Production method of sound absorbing material, sound absorbing material and silencer for automobile exhaust system - Google Patents

Description

  The present invention relates to a method for producing a sound absorbing material disposed inside an automobile exhaust system silencer, a sound absorbing material, and an automobile exhaust system silencer.

  Conventionally, a method of mainly enhancing the silencing effect of high-frequency components by filling a fiber material made of glass wool or metal wool as a sound-absorbing material into the silencer of an automobile exhaust system. In such a silencer, the work of filling the fiber material uniformly requires labor, and the fiber material easily scatters to the environment, causing a deterioration of the work environment, and in some cases causing a health hazard. There is. Further, even in the use stage for automobiles, there has been a problem that the exhaust gas causes the fiber material to scatter from the sound passage holes of the silencer and adversely affect the environment.

  Therefore, in order to solve this problem, the bag body is divided into a plurality of equal chambers by packing and sewing the fiber material into the bag body, and the sound absorbing material covered with such a bag body is placed inside the silencer. A method is known in which the fiber material is prevented from scattering by being inserted, and the bag body is divided into a plurality of pieces and the fiber material is uniformly filled to improve the silencing effect (see, for example, Patent Document 1). .

JP 2007-170315 A

  However, since the sound absorbing material as described above has a simple rectangular shape as a whole and the thickness of the sound absorbing material is substantially uniform, the shell 100 having a simple structure such as a so-called pre-silencer as shown in FIG. Although it is effective when filling the fiber material 102 between the exhaust pipes 101, there are some difficulties when filling the interior of the silencer having a complicated or narrow layout structure with many internal interferences. That is, the sound absorbing material packed in the bag interferes with the structure inside the silencer or the thickness of the sound absorbing material is insufficient depending on the installation location. In addition, there is a problem that the filling operation takes time. In addition, if the fiber material is unevenly filled in the silencer, abnormal noise may occur due to the fiber material moving in the silencer due to exhaust pressure, or density irregularity may occur in the fiber material. There was a problem that the silencing effect could not be demonstrated.

  The present invention has been made to solve such problems, and even when the sound absorbing material is filled into the silencer having a complicated internal structure, the sound absorber is closely attached to the wall surface inside the silencer. The sound absorbing material and the sound absorbing material are provided in such a manner that the sound absorbing material can be filled into a predetermined position of the silencer by a simple operation while ensuring a good working environment. It aims at providing the silencer provided with.

  According to the first aspect of the present invention, a fiber material is disposed on a bag-like member that is disposed in a predetermined part surrounded by a structure such as a shell or a separator inside a silencer for an exhaust system for automobiles and enhances the silencer function. A method for producing a filled sound absorbing material, wherein an upper sheet member and a lower sheet member made of a heat-resistant material, or an upper sheet portion and a lower sheet portion made of a heat-resistant material are sewn with a thread-like member, Form a bag-like member consisting of a plurality of bag parts, fill each bag part with fiber material, sew the part that interferes with the structure in the silencer with a thread-like member, and further fill the space in the silencer The portion where the thickness is insufficient is folded back at the sewn portion to ensure the thickness of the sound absorbing material.

  In this application, “interference” means that the sound absorbing material in a bag comes into contact with a structure such as a shell or a separator with excessive deformation or load on the sheet member or the sound absorbing material, and the sound absorbing material is appropriately compressed. However, when it comes into contact with the structure, it is simply expressed as “contact, contact, or close contact”.

A second aspect of the present invention is characterized in that a slit portion is formed at a portion that interferes with the structure in the silencer so that the structure in the silencer can be avoided as an integral bag-like member.
In the portion where the thickness of the sound absorbing material is reduced by sewing with a thread-like member, the width in the sewing direction of the sheet member is reduced so that the width of the sewing portion does not increase in a state where the fiber material is filled. To do.

  According to a fourth aspect of the present invention, there is provided a sound-absorbing material arranged in a closed space inside a silencer for an automobile exhaust system, which is manufactured by the manufacturing method according to the first to third aspects.

  A fifth aspect of the present invention is a muffler for an automobile exhaust system, wherein the sound absorbing material according to the fourth aspect is arranged.

  According to the invention of claim 1, in the state where the sound absorbing material filled with the fiber material is arranged in the closed space, the sheet member is manufactured so that the sound absorbing material is in close contact with the entire wall surface except for the corner of the closed space, In order to avoid interference with the structure in the device, the thickness of the sound absorbing material is reduced by sewing the sheet with a thread-like member. If the thickness of the sound absorbing material is insufficient, the sound absorbing material is sewn with the thread-like member. Since the thickness of the sound absorbing material is secured by folding the sound absorbing material at the folded part set by reducing the thickness of the sound absorbing material, when the sound absorbing material is filled into the silencer with a complicated layout structure with many interferences Even so, it can be placed in close contact with the inner wall of the silencer without interfering with the structure inside the silencer or the thickness of the sound absorber is insufficient, and the workability of assembling the sound absorber is improved. Improve It is possible. In addition, the fiber material is filled into the sheet member in a uniform state, and can be installed in close contact with the wall surface inside the silencer, and exhibits a silencing effect without causing uneven density of the fiber material or displacement of the sound absorbing material. can do. Moreover, since the fiber material is a sound-absorbing material covered with a bag, it is possible to easily perform the filling operation without preventing the fiber material from being scattered and causing a deterioration of the working environment.

  According to the invention of claim 2, by avoiding the structure in the silencer and forming the sheet member so as to be integrated by forming a slit portion at a portion that interferes with the structure, there are many interferences and complicated. Even when the sound absorbing material is filled in the silencer having the layout structure, the filling operation can be facilitated, and the disassembling operation at the time of recycling after use can be easily performed.

  According to the invention of claim 3, in the portion where the thickness of the sound absorbing material is reduced by sewing with the thread-like member, the width of the sound absorbing material is reduced in the state where the fiber material is filled by reducing the width in the sewing direction of the sheet member. Even if the sound absorbing material is folded back at the folded part set by reducing the thickness of the sound absorbing material, the sound absorbing material can be easily put inside the silencer without being sandwiched by the silencer shell or protruding from the outer cylinder. Can be installed.

(A) is a top view which shows the sound-absorbing material which concerns on this invention, (b) is the front view, (c) is the right view. (D) is a cross section AA. It is the schematic which shows the manufacturing process of the sound-absorbing material shown in FIG. (A) is a top view which shows the sheet | seat member of the sound-absorbing material which concerns on this invention, (b) is a top view after folding a sheet | seat member and sewing the edge part into bag shape, (c) is front and back (D) shows a state in which a predetermined portion is sewn and the bag-like member is completed in each housing portion. It is the schematic which showed the whole structure of the silencer of the Example. It is the figure which showed the structure which concerns on a prior art (Unexamined-Japanese-Patent No. 2007-170315).

  Hereinafter, an embodiment of a method for producing the sound absorbing material 1 of the present invention will be described with reference to FIGS. 1 and 2.

  Fig.1 (a) is a top view of the sound-absorbing material 1 of the present invention. The sound absorbing material 1 is composed of a bag-like member 6 having nonflammability and high heat resistance, and a glass fiber material 3 having excellent heat resistance accommodated in the bag-like member 6 shown in FIG. A plurality of accommodating portions 6 a capable of accommodating the glass fiber material 3 are formed inside the bag-like member 6.

  That is, the bag-shaped member 6 includes a first bag portion 6A that is long in the vertical direction in FIG. 1A, and a second bag portion 6B and a third bag portion 6C that are long in the left and right in FIG. Each of the first bag portion 6A, the second bag portion 6B, and the third bag portion 6C has an accommodating portion 6a that can accommodate the glass fiber material 3 therein. Between the first bag portion 6A, the second bag portion 6B, and the third bag portion 6C, a portion that does not have the accommodating portion 6a, that is, a thin interference avoiding portion 2e is provided.

  A predetermined gap is formed between the second bag portion 6B and the third bag portion 6C, whereby the bag-like member 6 has a bifurcated shape. Between the second bag portion 6B and the third bag portion 6C, a bracket 8 (shown in FIG. 3), which is one of the structures inside the silencer described later, is arranged. That is, the sound absorbing material 1 is formed in a bifurcated shape so as to avoid interference with the bracket 8 and is configured as an integral bag-like member 6.

  The sheet member 2 (shown in FIG. 2) constituting the bag-like member 6 is made of a glass cloth sewing product and has air permeability. The skin of the sheet member 2 prevents the internal glass fiber material 3 from being released or scattered to the outside, and has an aperture ratio suitable for incident sound to enter the inside of the skin. The air-borne sound that has entered the glass fiber material 3 through the skin is attenuated by internal pores, air viscosity, fiber vibration, and the like. The sound absorption coefficient, thickness, frequency characteristics, and the like of the glass fiber material 3 are set so as to match the noise characteristics of the engine to which the sound absorbing material 1 is attached. For example, Advantex (registered trademark) of Owens Corning Co. can be used as the glass fiber material 3.

  Next, a manufacturing method of the bag-like member 6 will be described with reference to FIG.

  First, the shape of the bag-like member 6 is filled with a predetermined glass fiber material 3 required for a desired silencing performance, and the bag-like member 6 is a structure such as a surrounding shell 10 or a separator 7 (shown in FIG. 3). It is designed to be in close contact with the flat portion of the plate and generate a predetermined pressure. As a result, the sound absorbing material 1 exhibits a sufficient silencing performance, and even when a vehicle vibration or the like is applied, problems such as misalignment or abnormal noise due to vibration do not occur inside the silencer.

  Conversely, the thickness of the bag-like member 6 is adjusted by sewing so as to avoid interference with the internal structure that would cause the bag-like member 6 to be damaged by contact.

  FIG. 2 is a view showing a manufacturing process of the bag-like member 6. As shown in FIG. 2A, a substantially line-symmetric sheet member 2 having a predetermined dimension is molded. For this, a normal automatic cutting device can be used.

  Next, the sheet member 2 is folded in two with the center line 2a as the center of bending, thereby being stacked in two layers. In FIG. 2, the upper sheet portion and the lower sheet portion are formed by bending one sheet member 2, but the present invention is not limited to this. For example, two sheet members cut in advance, that is, the upper sheet are formed. A member and a lower sheet member may be prepared, and the upper sheet member and the lower sheet member may be stacked.

  As shown in FIG. 2 (b), after the sheet member 2 is folded in two so that the outer edges of the upper and lower sheet portions overlap, a gap for avoiding interference with the structure inside the silencer is shown in FIG. 1 (a). In order to form between the second bag portion 6B and the third bag portion 6C shown, the slit portion 2b is formed over the upper and lower sheet portions, and then the upper and lower edges of the sheet member 2 and the periphery of the slit portion 2b are nonflammable and highly Sewing is performed using the thread-like member 4 having heat resistance. By sewing, a bag-like intermediate product is obtained in which the left side is opened in FIG. 2B and the right side is bifurcated.

  In addition, you may perform this formation of the slit part 2b at the process of shape | molding the sheet | seat member 2 of a previous process.

  Examples of the non-flammable and highly heat-resistant thread-like member 4 include thread-like members made of glass fiber, silica fiber, alumina fiber, bazaruto fiber, ceramic fiber, stainless steel fiber, metal fiber, carbon fiber, aramid fiber, and zylon fiber. . A thread-like member made of glass fiber is desirable from the viewpoint of cost. High heat resistance refers to the property that the shape can be maintained at the ambient temperature when used inside an automobile silencer.

  Next, it is reversed so that the inner surface of the intermediate product shown in FIG. 2 (b) becomes the outer surface so that the sheet portion outside the sewn portion is accommodated inside. As a result, as shown in FIG. 2 (c), a bag-like intermediate manufactured product is formed in which the sheet portion outside the part that has been sewed enters, and the right side in FIG. 2 (c) has a bifurcated shape. Reference numeral 2g also indicates a part.

  Further, as shown in FIG. 2 (d), the formation of a bent portion and sewing for avoiding the structure inside the silencer are performed.

  First, sewing is performed along the folding line L that becomes the folded portion, that is, the folded portion 2c, and the thickness of the sound absorbing material 1 is reduced at the sewing portion, so that the sound absorbing material 1 can be easily assembled in the silencer manufacturing process. Like that. At this time, the upper and lower end portions of the sewing portion indicated by reference numeral 2d in FIG. 2 (d) are folded back to the opposite side with a predetermined length to perform sewing, so that the second bag portion 6B and the third bag portion 6C are sewn at the sewing portion. The width in the sewing direction (vertical direction in FIG. 2D) is reduced. As a result, the glass fiber material 3 is filled into the bag-like member 6, and even when the center of the bag-like member 6 is inflated, the sewing portion that is the end portion does not protrude, and the assembling work inside the silencer can be performed. It becomes easy.

  In addition, linear sewing is performed at two locations close to the interference avoiding portion 2e that needs to avoid interference with the tail pipe 9 (shown in FIG. 3) inside the silencer. Thereby, between two linear sewing parts, it becomes a part by which the filling of the glass fiber material 3 was restrict | limited by the desired width | variety, and interference with the tail pipe 9 can be avoided.

  Finally, the left-side opening portion is sewn along the end 2f, whereby the bag-like member 6 having a predetermined shape having a plurality of accommodating portions 6a surrounded by the sheet-like member and the sewn portion is completed.

  Next, the process of filling the bag-like member 6 with the glass fiber material 3 will be described. The weight necessary for exhibiting the desired silencing performance is calculated in advance for each housing portion 6a.

  The glass fiber material 3 is filled in each housing portion 6a by inserting a filling nozzle (not shown), which is a known method, into each chamber of the bag-like member 6 and filling the glass fiber material 3 with a predetermined weight. To do.

  Next, a method for assembling the bag-like member 6 to the silencer will be described with reference to FIG.

  In the present embodiment, an outer shell is formed by an upper shell (not shown) and a lower shell 10, and a silencer having a structure such as a plurality of tail pipes 9, separators 7, and brackets 8 is partitioned by the separators 7. The sound absorbing material 1 is assembled in one substantially closed space. As shown in FIG. 3, the sound absorbing material 1 is assembled with the tail pipe 9, the bracket 8, and the like disposed on the lower shell 10. On the front side of the drawing, a bracket 8 is disposed at the center in parallel with the separator 7 and a tail pipe 9 is disposed at the center of the drawing. .

  As described above, the sound absorbing material 1 is also formed with the part 2g, and the bracket 8 is positioned between the second bag part 6B and the third bag part 6C formed by the formation of the part 2g. The second bag portion 6B and the third bag portion 6C are accommodated in the lower shell 10. Thereby, the sound absorbing material 1 can be accommodated in a predetermined portion in the lower shell 10 while avoiding interference with the bracket 8. At this time, the thickness of the sound-absorbing material 1 can be easily increased by folding the second bag portion 6B and the third bag portion 6C along the fold-back portion 2c that has been sewn. Material 1 can be filled. Further, both ends of the folded portion 2c do not protrude even after being bent by the effect of the sewing portion 2d described above, and assembly is not hindered.

  Since the portion overlapping the tail pipe 9 is the interference avoiding portion 2e in which the thickness of the sound absorbing material 1 is reduced by two-line linear sewing as described above, the sound absorbing material 1 is avoided while avoiding interference with the tail pipe 9. Can be arranged.

  Thereafter, an upper shell (not shown) is placed on the lower shell 10 from above and joined to the lower shell 10 by seam welding or the like. As described above, the widths of the second bag portion 6B and the third bag portion 6C of the sound-absorbing material 1 are kept below a certain level by the sewing portions 2d at both ends of the bent portion 2c. The sound absorbing material 1 can be easily installed inside the silencer without protruding or protruding between the upper shell and the lower shell 10. At this time, the internal sound absorbing material 1 is appropriately compressed by the upper shell, generates a predetermined density and a repulsive force, is held at a predetermined portion, and exhibits a desired silencing action.

  As described above, when the sound absorbing material 1 is disposed in the closed space inside the sound deadening device, interference with the structure inside the sound deadening device can be avoided by the sewn part, and the folded portion 2c installed in the sound absorbing material 1 can be avoided. Thus, even when the thickness of the sound absorbing material 1 is insufficient, the thickness of the sound absorbing material 1 can be ensured by folding back at the folded portion 2c. Therefore, even when the sound absorbing material 1 is installed in a complicated or narrow closed space inside the silencer, the sound absorbing material 1 can be arranged so as to be in contact with the planar portion of the surrounding structure constituting the closed space inside the silencer. This makes it possible to exhibit a desired silencing action while appropriately holding the sound absorbing material 1.

  Although the preferred embodiments of the present invention have been described in detail, the present invention is not limited to the above-described embodiments, and can be modified or changed within the scope of the present invention described in the claims. . For example, when the sheet member 2 is sewn on the folding line L, the sheet member 2 may be sewn entirely in a straight line, or may be partially sewn, such as a dotted or broken line. . In addition, by arranging the linear sewing in parallel and adjusting the needle width, the thickness of the sound absorbing material when folded can be more evenly secured.

  As described above, the present invention can be applied to, for example, an automobile exhaust system silencer.

DESCRIPTION OF SYMBOLS 1 Sound absorption material 2 Sheet | seat member 2a Center line 2b Slit part 2c Folding part 2d Sewing part 2e Interference avoiding part 2g Moreover part 3 Glass fiber material 4 Threaded member 6 Bag-shaped member 7 Separator 8 Bracket 9 Tail pipe 10 Lower shell 10

Claims (5)

A method for producing a sound absorbing material in which a bag-like member is filled with a fiber material, which is disposed in a predetermined portion surrounded by a structure such as a shell or a separator in an exhaust system for an automobile exhaust system, and enhances the sound deadening function. ,
An upper sheet member and a lower sheet member made of a heat-resistant material, or an upper sheet portion and a lower sheet portion made of a heat-resistant material are sewn with a thread-like member to form a bag-shaped member made up of a plurality of bag portions. And
Fill each bag with fiber material,
The part that interferes with the structure in the silencer is sewn with a thread-like member, and the part where the thickness is insufficient to fill the space in the silencer is folded back at the sewn part to ensure the thickness of the sound absorbing material. The production method of sound-absorbing material.   2. The sound absorbing material according to claim 1, wherein a slit portion is formed in a portion that interferes with the structure in the silencer so that the structure in the silencer can be configured as an integral bag-like member while avoiding the structure in the silencer. Production method.   In the portion where the thickness of the sound absorbing material is reduced by sewing with a thread-like member, the width in the sewing direction of the sheet member is reduced so that the width of the sewing portion is not increased in a state where the fiber material is filled. A method for producing a sound absorbing material according to claim 1 or 2.   A sound-absorbing material, which is manufactured by the manufacturing method according to any one of claims 1 to 3, is disposed inside a silencer for an automobile exhaust system.   A sound absorbing device for an automobile exhaust system, wherein the sound absorbing material according to claim 4 is disposed.

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