JPWO2020195244A1 - Automotive silencer - Google Patents

Abstract

The press-molded silencer for automobiles includes a first fiber layer 110 and a second fiber layer 120. The first fiber layer 110 contains 60 to 99% by weight of the main fiber 115 containing a non-melting component and 1 to 40% by weight of the thermoplastic fiber 116. The second fiber layer 120 contains 50 to 100% by weight of the thermoplastic fiber 126. The silencer 1 may further include a third fiber layer 130 containing 60 to 99% by weight of the main fiber 135 containing the non-molten component and 1 to 40% by weight of the thermoplastic fiber 136. The second fiber layer 120 may be located between the first fiber layer 110 and the third fiber layer 130.

Description

The present invention relates to a press-molded silencer for an automobile.

As a silencer installed in an automobile, for example, a floor silencer interposed between a floor panel and a floor carpet is known. The floor silencer not only provides soundproofing performance, but also has the function of preventing the unevenness of the floor panel from appearing on the surface of the carpet and the function of giving the occupant a good feel when stepping on it. As a silencer for realizing these functions, for example, as shown in International Publication No. 2015/146428, a fibrous silencer containing an inexpensive clothing anti-hair fiber as a main component is used.

International Publication No. 2015/146428

Reducing the weight of the silencer may reduce the footing feel when stepping on the floor carpet. In addition, when the silencer has a low density, there is a possibility that when the floor carpet is stepped on by the foot, the silencer is compressed in the thickness direction and does not return to the original thickness.
It should be noted that the above problems are not limited to the silencer for floor carpets, but also exist for various automobile silencers such as dash silencers.

The present invention discloses an automobile silencer capable of obtaining an appropriate compression strength even if the weight is reduced.

The present invention is a press-molded silencer for automobiles.
A first fiber layer containing 60 to 99% by weight of a main fiber containing a non-melted component and 1 to 40% by weight of a thermoplastic fiber.
A second fiber layer containing 50 to 100% by weight of thermoplastic fibers,
Has aspects, including.

Further, the present invention is a press-molded silencer for automobiles.
The first fiber layer containing the thermoplastic fiber and the second fiber layer containing the thermoplastic fiber having a weight ratio higher than the weight ratio of the thermoplastic fiber contained in the first fiber layer are included.
The silencer has a thickness of 20 mm or more and has a thickness of 20 mm or more.
The density of the silencer is 0.10 g / cm ³ or less.
The thickness of the silencer and X mm, when the basis weight of the second fiber layer was Yg / m ^2, the basis weight Y is ^{Y ≧ 1.068 · X 2 -23.12 ·} X + 176.4,
When a load of 50 N is applied to a disk having a diameter of 50 mm placed on the surface of the silencer in the thickness direction of the silencer, the distance that the silencer is recessed is 15 mm or less.

According to the present invention, it is possible to provide an automobile silencer capable of obtaining an appropriate compression strength even if the weight is reduced.

FIG. 1 is a perspective view schematically illustrating the appearance of the silencer and the skin material on the passenger compartment side. FIG. 2 is a diagram schematically illustrating a main part of a vertical end surface when a silencer is cut together with a vehicle body panel and a skin material at a position corresponding to A1-A1 in FIG. FIG. 3 is a diagram schematically showing another example of the fiber structure in the second fiber layer. FIG. 4 is a diagram schematically illustrating a main part of a vertical end surface when another silencer is cut together with a vehicle body panel and a skin material at a position corresponding to A1-A1 in FIG. FIG. 5 is a diagram schematically illustrating a main part of a vertical end surface when another silencer is cut together with a vehicle body panel and a skin material at a position corresponding to A1-A1 in FIG. FIG. 6 is a diagram schematically showing an example of a silencer. FIG. 7 is a diagram schematically showing an example of measuring the amount of dent of the silencer by a disk to which a load is applied in the thickness direction. FIG. 8 is a diagram showing the relationship between the basis weight of the second fiber layer and the amount of dent in the silencer. FIG. 9 is a diagram showing the relationship between the thickness of the silencer and the basis weight of the second fiber layer. FIG. 10 is a diagram schematically showing an example of a silencer manufacturing apparatus. FIG. 11 is a vertical end view for explaining an example of a molding process.

Hereinafter, embodiments of the present invention will be described. Of course, the following embodiments merely exemplify the present invention, and not all of the features shown in the embodiments are essential for the means for solving the invention.

(1) Outline of the technique included in the present invention:
First, an outline of the technique included in the present invention will be described with reference to the examples shown in FIGS. It should be noted that the figures of the present application are diagrams schematically showing examples, and the enlargement ratios in each direction shown in these figures may be different, and the figures may not be consistent. Of course, each element of the present technology is not limited to the specific example indicated by the reference numeral.
Further, in the present application, the numerical range "Min to Max" means a minimum value of Min or more and a maximum value of Max or less.

[Aspect 1]
The press-molded silencer 1 for automobiles according to one aspect of the present technology includes a first fiber layer 110 and a second fiber layer 120. The first fiber layer 110 contains 60 to 99% by weight of the main fiber 115 containing a non-melting component and 1 to 40% by weight of the thermoplastic fiber 116. The second fiber layer 120 contains 50 to 100% by weight of the thermoplastic fiber 126.

As a result of repeated studies, even if the weight was reduced by combining the first fiber layer 110 containing a large amount of the main fiber 115 containing a non-melting component with the second fiber layer 120 having a large weight ratio of the thermoplastic fibers. It was found that an appropriate compression strength can be obtained. Since the press-formed second fiber layer 120 contains 50% by weight or more of the thermoplastic fibers 126, the thermoplastic fibers 126 fused to each other give high rigidity to the second fiber layer 120, which is a silencer. It is presumed that the compression strength of the silencer 1 is maintained even if the weight of 1 is reduced. Further, the press-molded first fiber layer 110 contains 60% by weight or more of the main fiber 115 containing a non-melting component, which gives flexibility to the first fiber layer 110, which gives the feel of the silencer 1. It is presumed that it is improving. Since the press-molded first fiber layer 110 contains 1% by weight or more of the thermoplastic fiber 116, the shape of the first fiber layer 110 is maintained. In the press-molded silencer 1, it is presumed that an appropriate compressive strength can be obtained even if the weight is reduced by combining the appropriate rigidity of the second fiber layer 120 and the flexible feel of the first fiber layer 110. ..
From the above, the above aspect 1 can provide a press-molded silencer for automobiles, which can obtain an appropriate compressive strength even if the weight is reduced.

Here, the places where the silencer of this technology can be installed include the passenger compartment floor, the passenger compartment side wall, the passenger compartment ceiling, the deck floor, the dashboard, the engine hood, the fender, etc. It may be a part or an exterior part.
The main fibers containing non-melt components include anti-hair fibers such as clothing anti-hair fibers, non-melt fibers such as cellulosic fibers, and the like.
In the present application, "first", "second", "third", ... Are terms for identifying each component included in a plurality of components having similarities to each other, and do not mean an order. Which of the plurality of components corresponds to "first", "second", "third", ... Is relatively determined.
The thermoplastic fiber of the first fiber layer and the thermoplastic fiber of the second fiber layer may be the same type of fiber or different types of fiber.
The above-mentioned additional notes are also applied in the following aspects.

[Aspect 2]
By the way, the thickness T0 of the silencer 1 may be 20 mm or more. The density of the silencer 1 ^{may be 0.10 g / cm 3} or less. The thickness T0 of the silencer 1 and X mm, when the basis weight of the second fiber layer 120 was set to Yg / m ^2, the basis weight Y good even ^{Y ≧ 1.068 · X 2 -23.12 ·} X + 176.4. The distance (recess amount L0 shown in FIG. 7) that the silencer 1 is recessed when a load F of 50 N is applied in the thickness T0 direction of the silencer 1 to the disk 500 having a diameter of 50 mm placed on the surface 10 of the silencer 1 may be 15 mm or less. ..

Was subjected to repeated study, basis weight Y of the second fiber layer 120 is a ^{Y ≧ 1.068 · X 2 -23.12 ·} X + 176.4, silencer 1 dented L0 is 15mm or less, density It was found that the feel when pushed in the thickness direction D3 was further improved even at 0.10 g / cm ^{3 or less.} Therefore, the above aspect 2 can provide an automobile silencer capable of obtaining a more appropriate compression strength.

[Aspect 3]
As illustrated in FIG. 2, the silencer 1 further contains a third fiber layer 130 containing 60 to 99% by weight of the main fiber 135 containing a non-melting component and 1 to 40% by weight of the thermoplastic fiber 136. May be good. The second fiber layer 120 may be located between the first fiber layer 110 and the third fiber layer 130. This aspect can provide an automotive silencer capable of further improving the feel when pushed in the thickness direction.
Here, the main fiber of the first fiber layer and the main fiber of the third fiber layer may be the same type of fiber or different types of fiber. Further, the thermoplastic fiber of the first fiber layer and the thermoplastic fiber of the third fiber layer may be the same type of fiber or different types of fiber.

[Aspect 4]
By the way, the press-molded silencer 1 for automobiles according to one aspect of the present technology is based on the weight ratio of the first fiber layer 110 containing the thermoplastic fiber 116 and the thermoplastic fiber 116 contained in the first fiber layer 110. It also includes a second fiber layer 120, which includes a thermoplastic fiber 126 with a high weight ratio. The thickness T0 of the silencer 1 is 20 mm or more. The density of the silencer 1 is 0.10 g / cm ³ or less. The thickness T0 of the silencer 1 and X mm, when the basis weight of the second fiber layer 120 was set to Yg / m ^2, the basis weight Y is ^{Y ≧ 1.068 · X 2 -23.12 ·} X + 176.4. When a load F of 50 N is applied to the disk 500 having a diameter of 50 mm placed on the surface 10 of the silencer 1 in the thickness direction D3 of the silencer 1, the distance that the silencer 1 is recessed (the recess amount L0 shown in FIG. 7) is 15 mm or less. be.

As a result of repeated studies, the second fiber layer 120 in which the weight ratio of the thermoplastic fiber was increased was combined with the first fiber layer 110, and the texture Y of the second fiber layer 120 was Y ≧ 1.068 · X ² It was found that an appropriate compressive strength can be obtained even ^{when the density of the silencer 1 is 0.10 g / cm 3} or less by setting the dent amount L0 of the silencer 1 to -23.12 · X + 176.4 or less. The weight ratio of thermoplastic fibers 126 of the second fiber layer 120 which is press-molded is large, by basis weight Y of the second fiber layer 120 is ^{Y ≧ 1.068 · X 2 -23.12 ·} X + 176.4, It is presumed that the thermoplastic fibers 126 fused to each other give high rigidity to the second fiber layer 120, which maintains the compressive strength of the silencer 1 even if the silencer 1 is made lighter. Further, it is presumed that the small weight ratio of the thermoplastic fibers 116 of the press-molded first fiber layer 110 gives flexibility to the first fiber layer 110, which improves the feel of the silencer 1. NS. Further, when the recess amount L0 of the silencer 1 is 15 mm or less, the feel of the silencer 1 is further improved. Since the press-molded first fiber layer 110 contains the thermoplastic fiber 116, the shape of the first fiber layer 110 is maintained. In the press-molded silencer 1, it is presumed that an appropriate compressive strength can be obtained even if the weight is reduced by combining the appropriate rigidity of the second fiber layer 120 and the flexible feel of the first fiber layer 110. ..
From the above, the above aspect 4 can provide a press-molded silencer for automobiles, which can obtain an appropriate compressive strength even if the weight is reduced.

(2) Specific examples of automobile silencers:
FIG. 1 schematically illustrates a press-molded silencer for an automobile and a press-molded skin material for an automobile. In FIG. 1, FRONT, REAR, LEFT, RIGHT, UP, and DOWN indicate front, rear, left, right, top, and bottom, respectively. The left-right positional relationship is based on the direction in which the vehicle is viewed. FIG. 2 schematically illustrates a main part of a vertical end face when a silencer is cut together with a vehicle body panel and a skin material at a position corresponding to A1-A1 in FIG.

On the floor panel (body panel 80) in the passenger compartment of an automobile, the floor panel is usually covered and shielded by laying a floor carpet (skin material) 20 as illustrated in FIG. As a result, the interior design of the occupant's room and the treading comfort, which means a good feel when the occupant steps on the foot, are imparted. In order to absorb the unevenness formed on the floor panel and secure the flatness of the floor surface, the floor silencer 1 functioning as a raising material is installed between the floor panel and the floor carpet 20.

From the need for improving quietness in the vehicle interior, as illustrated in FIG. 1, the silencer 1 is integrally or separately formed so as to cover the entire back surface of the floor carpet, and covers the entire floor panel. The large silencer 1 shown in FIG. 1 is formed into an integrally molded product that covers the entire surface of the floor panel by being molded so that the thickness and basis weight differ for each region according to the unevenness of the floor panel. The function as is given. As a result, the silencer 1 simultaneously exerts the functions of sound absorption and sound insulation against the noise that has entered from the outside of the vehicle. That is, the floor silencer laid on the vehicle body panel is molded and laid in a shape along the unevenness of the vehicle body panel, and is used for ensuring the performance of the vehicle floor such as cushioning and soundproofing. .. In addition to being installed on the floor, the automobile silencer of this technology can be adapted to the shape of parts such as the side wall of the passenger compartment, the ceiling of the passenger compartment, the deck floor, the dashboard, the engine hood, and the fender. It is also possible to install it at the site.

The automobile silencer 1 shown in FIG. 1 includes a substantially flat floor panel (a type of vehicle body panel 80) constituting the floor surface of the vehicle body, and a toe board panel (of the vehicle body panel 80) rising upward from the floor panel surface in the front part of the passenger compartment. It is said to be a functional material that is placed on top of (a type), etc. The silencer 1 for the passenger compartment is laid on the passenger compartment C1 side of the vehicle body panel 80. The silencer 1 shown in FIG. 1 is aligned with the tunnel portion 14 that bulges upward and extends forward and backward in accordance with the tunnel portion of the vehicle body panel, and each substantially flat portion of the vehicle body panel on the outer side in the vehicle width direction from the tunnel portion 14. Each of the substantially flat portions 13 is formed into a three-dimensional shape so as to follow the standing wall of a protruding portion such as a console or a rocker panel. A floor carpet 20 is laid on the passenger compartment C1 side of the silencer 1. The floor carpet 20 is formed into a three-dimensional shape along the standing wall of the protrusion of the silencer 1 to decorate the passenger compartment.

The floor carpet 20 shown in FIG. 1 is press-molded to form an uneven shape 22 on the vehicle interior C1 side, and is arranged so as to face the vehicle interior C1. The uneven shape 22 includes a footrest portion 23 on each substantially flat portion 13 of the silencer 1. The carpet 20 is, for example, a tufted carpet having a backstitch of the pile 26 on the base layer 25, and a large number of piles 26 are raised on the vehicle interior C1 side of the base layer 25. As the base fabric constituting the base layer 25, a non-woven fabric such as a spunbonded non-woven fabric, a knitted fabric of various fibers, or the like can be used. The back side of the base cloth (the surface on the silencer 1 side) may be lined. A resin material (including an elastomer), a fiber material, or the like can be used for this lining. Of course, for the carpet 20, it is also possible to adopt a needle punch carpet or the like in which a non-woven fabric is kneaded and fibers are entwined with each other to form fluff on the surface.

In the silencer 1 shown in FIGS. 1 and 2, uneven shapes are formed by press molding on the first and second molding surfaces 11 and 12 which are opposite to each other in the thickness direction D3, and the vehicle body panel 80 and the floor carpet 20 are formed. It is installed between and. Here, the first molding surface 11 is on the carpet 20 side, and the second molding surface 12 is on the vehicle body panel 80 side. In this case, the first molding surface 11 is the surface 10 on which the disk 500 shown in FIG. 7 is placed. The silencer 1 includes a first fiber layer 110, a second fiber layer 120, and a third fiber layer 130 in this order from the first molding surface 11 to the second molding surface 12. The first fiber layer 110 includes the first molding surface 11. The second fiber layer 120 includes a first adhesive surface 121 to which the first fiber layer 110 is adhered and a second adhesive surface 122 to which the second fiber layer 120 is adhered. The third fiber layer 130 includes a second molding surface 12.
As a result of repeated studies, it was found that an appropriate compression strength can be obtained even if the silencer 1 is made lighter under the conditions described later.

The first fiber layer 110 contains 60 to 99% by weight of the main fiber 115 containing a non-melting component and 1 to 40% by weight of the thermoplastic fiber 116. Here, the main fiber 115 and the thermoplastic fiber 116 are collectively referred to as a fiber 114. The fibers 114 are randomly oriented. The third fiber layer 130 contains 60 to 99% by weight of the main fiber 135 containing a non-melting component and 1 to 40% by weight of the thermoplastic fiber 136. Here, the main fiber 135 and the thermoplastic fiber 136 are collectively referred to as a fiber 134. The fibers 134 are randomly oriented. The second fiber layer 120 between the first fiber layer 110 and the third fiber layer 130 contains 50 to 100% by weight of the thermoplastic fiber 126. That is, all the fibers 124 of the second fiber layer 120 may be the thermoplastic fibers 126, or as shown in FIG. 3, the auxiliary fibers 125 containing the non-melting component may be contained together with the thermoplastic fibers 126. Here, the thermoplastic fiber 126 and the auxiliary fiber 125 are collectively referred to as the fiber 124. The fibers 124 are randomly oriented.

The main fibers 115 and 135 and the auxiliary fibers 125 may contain non-melt components, and anti-hair fibers such as clothing anti-hair fibers, natural fibers such as cellulose-based fibers and animal fibers, and the like can be used. Cellulose-based fibers include plant fibers such as cotton and hemp, synthetic fibers such as rayon, and the like. Plant fiber is also a natural fiber. Animal fibers include wool, silk, and the like. It should be noted that the clothing anti-hair fibers may be mixed with thermoplastic fibers having a high melting point of 220 ° C. or higher, such as polyester fibers and polyamide fibers.

The fineness of the main fibers 115 and 135 and the auxiliary fibers 125 is not particularly limited, but may be, for example, about 2.2 to 16 dtex. The lengths of the main fibers 115 and 135 and the auxiliary fibers 125 are not particularly limited, but may be, for example, about 27 to 76 mm. The cross-sectional shapes of the main fibers 115 and 135 and the auxiliary fibers 125 are not particularly limited, and may be an ellipse including a perfect circle, a triangle, a flat shape, or the like. Further, the main fibers 115 and 135 and the auxiliary fibers 125 may be hollow fibers having a hollow cross section.
Of course, a plurality of types of fibers may be combined with the main fibers 115 and 135 and the auxiliary fibers 125.

Further, the same type of fiber may be used for the main fibers 115 and 135, or different types of fibers may be used. As the auxiliary fiber 125 when used in the second fiber layer 120, the same type of fiber as the main fibers 115 and 135 may be used, or a different type of fiber from the main fibers 115 and 135 may be used. good.

The melting points of the thermoplastic fibers 116, 126, 136 are preferably 80 to 200 ° C. The melting points of the thermoplastic fibers 116, 126, 136 are more preferably 90 ° C. or higher, further preferably 100 ° C. or higher, in order to suppress the plasticization of the thermoplastic fibers due to the temperature rise in the automobile. Further, in order to facilitate the molten state of the thermoplastic fiber during press molding, the melting points of the thermoplastic fibers 116, 126, 136 are more preferably 190 ° C. or lower, further preferably 180 ° C. or lower, and particularly preferably 160 ° C. or lower. As the thermoplastic fibers 116, 126, 136 having such a low melting point, fibers made of a thermoplastic resin (including a thermoplastic elastomer) are preferable. The thermoplastic resin includes polyester resin such as polyethylene terephthalate (PET) resin, polyolefin resin such as polypropylene (PP) resin and polyethylene (PE) resin, modified resin obtained by adding an elastomer to these synthetic resins, and these synthetic resins. A material to which an additive such as a colorant is added can be used. As the thermoplastic fibers 116, 126, 136, it is also possible to use a conjugate fiber having a conjugate structure such as a core sheath structure or a side-by-side structure. In this case, some of the plurality of components contained in the conjugated fiber may be components having a high melting point of, for example, exceeding 200 ° C.

The fineness of the thermoplastic fibers 116, 126, 136 is not particularly limited, but can be, for example, about 2.2 to 16 dtex. The lengths of the thermoplastic fibers 116, 126, 136 are not particularly limited, but can be, for example, about 27 to 76 mm. The cross-sectional shape of the thermoplastic fibers 116, 126, 136 is not particularly limited, and may be an ellipse including a perfect circle, a triangle, a flat shape, or the like. Further, the thermoplastic fibers 116, 126, 136 may be hollow fibers having a hollow cross section.
Of course, the thermoplastic fibers 116, 126, 136 may be combined with a plurality of types of fibers.

Further, as the thermoplastic fibers 116 and 136, the same type of fibers may be used, or different types of fibers may be used. As the thermoplastic fiber 126 of the second fiber layer 120, the same type of fiber as the thermoplastic fiber 116, 136 may be used, or a type of fiber different from the thermoplastic fiber 116, 136 may be used.

In the first fiber layer 110 and the third fiber layer 130, the compounding ratio of the main fibers 115 and 135 is 60% by weight or more, and the compounding ratio of the thermoplastic fibers 116 and 136 is 40% by weight or less. This is to give the silencer 1 an appropriately flexible feel (for example, stepping property through the carpet 20). From the viewpoint of further improving the feel of the silencer 1, it is more preferable that the blending ratio of the main fibers 115 and 135 is 65% by weight or more and the blending ratio of the thermoplastic fibers 116 and 136 is 35% by weight or less. Further, in the fiber layers 110 and 130, the compounding ratio of the main fibers 115 and 135 is 99% by weight or less, and the compounding ratio of the thermoplastic fibers 116 and 136 is 1% by weight or more. This is to prevent the fiber layers 110 and 130 from collapsing after press molding. It is more preferable that the blending ratio of the main fibers 115 and 135 is 95% by weight or less and the blending ratio of the thermoplastic fibers 116 and 136 is 5% by weight or more in order to better maintain the shapes of the fiber layers 110 and 130. It is more preferable that the compounding ratio of the main fibers 115 and 135 is 90% by weight or less and the compounding ratio of the thermoplastic fibers 116 and 136 is 10% by weight or more, and the compounding ratio of the main fibers 115 and 135 is 80% by weight or less. It is particularly preferable that the blending ratio of the thermoplastic fibers 116 and 136 is 20% by weight or more.
Of course, the blending ratio of the main fiber 115 and the blending ratio of the main fiber 135 may be the same or different.

In the second fiber layer 120, the compounding ratio of the thermoplastic fiber 126 is 50% by weight or more, and the compounding ratio of the auxiliary fiber 125 is 50% by weight or less. This is to give high rigidity to the second fiber layer 120 by the thermoplastic fibers 126 fused to each other, and to give good compressive strength to the lightweight silencer 1. From the viewpoint of further increasing the rigidity of the second fiber layer 120, it is more preferable that the compounding ratio of the thermoplastic fiber 126 is 70% by weight or more and the compounding ratio of the auxiliary fiber 125 is 30% by weight or less, and the compounding ratio of the thermoplastic fiber 126 is further increased. It is more preferable that the ratio is 90% by weight or more and the compounding ratio of the auxiliary fiber 125 is 10% by weight or less, and the compounding ratio of the thermoplastic fiber 126 is 95% by weight or more and the compounding ratio of the auxiliary fiber 125 is 5% by weight or less. It is particularly preferable to have.

The third fiber layer 130 described above can be omitted as illustrated in FIGS. 4 and 5.
In the silencer 1 shown in FIG. 4, the first fiber layer 110 on which the first molded surface 11 facing the carpet 20 is formed and the second fiber on which the second molded surface 12 facing the vehicle body panel 80 is formed. It contains layer 120. In this case, the first molding surface 11 is the surface 10 on which the disk 500 shown in FIG. 7 is placed. The second fiber layer 120 includes an adhesive surface 121 to which the first fiber layer 110 is adhered. In the silencer 1 shown in FIG. 4, the second fiber layer 120 is supported by the vehicle body panel, so that the second fiber layer 120 has a high rigidity and the compressive load transmitted from the carpet 20 to the flexible first fiber layer 110 is supported. Therefore, the silencer 1 shown in FIG. 4 has a good feel (for example, stepping property) when pushed in the thickness direction, and can obtain an appropriate compressive strength even if the weight is reduced. Further, when the skin material (for example, the carpet 20) has air permeability in the thickness direction, sound waves from the vehicle interior C1 enter the silencer 1 through the skin material, so that the silencer 1 exerts a sound absorbing function. Therefore, the flow resistance value on the vehicle interior C1 side can be controlled by the first fiber layer 110, and the sound absorption property can be improved.

The silencer 1 shown in FIG. 5 has a second fiber layer 120 on which a second molded surface 12 facing the carpet 20 is formed, and a first fiber on which a first molded surface 11 facing the vehicle body panel 80 is formed. Includes layer 110. In this case, the second molding surface 12 is the surface 10 on which the disk 500 shown in FIG. 7 is placed. The second fiber layer 120 includes an adhesive surface 121 to which the first fiber layer 110 is adhered. In the silencer 1 shown in FIG. 5, since the flexible first fiber layer 110 is provided between the second fiber layer 120 and the vehicle body panel 80, the compressive load transmitted from the carpet 20 to the highly rigid second fiber layer 120 is applied. It is received in a wide range of the flexible first fiber layer 110. Therefore, the silencer 1 shown in FIG. 5 can obtain a more appropriate compression strength.

The silencer 1 shown in FIG. 2 has a third fiber layer 130 between the second fiber layer 120 and the vehicle body panel 80 as compared with the case shown in FIG. 4, so that the carpet 20 to the first fiber layer 110 can be separated. The compressive load transmitted through the highly rigid second fiber layer 120 is received in a wide range of the flexible third fiber layer 130. Therefore, a more appropriate compression strength can be obtained. Further, the silencer 1 shown in FIG. 2 is transmitted from the carpet 20 to the flexible first fiber layer 110 because the fiber layers 110 and 130 are provided on both sides of the second fiber layer 120 as compared with the case shown in FIG. It is supported by a rigid second fiber layer 120 having a high compressive load. Therefore, the feel when pushed in the thickness direction (for example, stepping property) is good, and an appropriate compressive strength can be obtained even if the weight is reduced.

As illustrated in FIG. 6, the second fiber layer 120 described above may be arranged on a part of the facing surface 111 on the opposite side of the first fiber layer 110 from the first molding surface 11. FIG. 6 schematically illustrates the body panel 80 side of the press-molded silencer 1. The lower part of FIG. 6 schematically illustrates a vertical cross section when the silencer 1 is cut at the positions A2-A2. The second fiber layer 120 has a partially different basis weight and is integrated with the facing surface 111 of the first fiber layer 110 having a substantially uniform basis weight. The third fiber layer 130 has a substantially uniform basis weight, and faces the second fiber layer 120 on the first fiber layer 110 and the facing surface 111 in the first fiber layer 110 of the portion of the second fiber layer 120 where there is no fiber. Is integrated into. The basis weights of the layers 110, 120, and 130 and the basis weight of the silencer 1 are the weights per unit area in a virtual plane orthogonal to the thickness direction D3 of the silencer 1.

The second molded surface 12 formed on the third fiber layer 130 is an uneven surface 140. The uneven surface 140 is formed with a convex portion 141 substantially corresponding to the portion of the second fiber layer 120 in which the fiber exists, and a concave portion 142 substantially corresponding to the portion of the second fiber layer 120 in which the fiber does not exist. .. The convex portion 141 has a relatively high convex portion 141a and a relatively low convex portion 141b.
The silencer without the third fiber layer 130 shown in FIG. 6 is also included in the present technology.

The density of the entire silencer 1 described above ^{is preferably 0.03 g / cm 3 or more in terms of imparting good compressive strength to the silencer, and 0.10 g / cm 3} or less in terms of imparting an appropriately flexible feel to the silencer. preferable.

FIG. 7 schematically illustrates a method of measuring the compression strength of the silencer 1 with the recess amount L0. The sample SA of the silencer 1 may have an area of 200 mm square or more. The dent amount L0 is the distance at which the sample SA is dented when a load F of 50 N is applied to the disk 500 having a diameter of 50 mm placed on the surface SA1 of the sample SA in the thickness direction D3 of the sample SA by a pressurizing device (not shown). .. The surface SA1 corresponds to the surface 10 of the silencer 1 shown in FIGS. 2, 4 and 5. The load F of 50N is a load set by assuming that the load F is applied to the silencer 1 from the feet of an occupant sitting on a seat of an automobile.

The combined basis weight of the first fiber layer 110 and the third fiber layer 130 ^{is preferably 600 g / m 2} or more in terms of imparting an appropriately flexible feel to the silencer, and 1000 g / m 2 in terms of imparting good compressive strength to the silencer. M ² or less is preferable, and 800 g / m ² is particularly preferable.

This specific example has a feature that the basis weight of the second fiber layer 120 is set according to the thickness T0 of the silencer 1 shown in FIGS. 2, 4 and 5. Hereinafter, the basis weight conditions of the second fiber layer 120 will be described with reference to FIGS. 8 and 9.

FIG. 8 shows a recess amount L0 according to the basis weight of the silencer 1 when the basis weights of the fiber layers 110 and 130 are 400 g / m ² , that is, the basis weight of the fiber layers 110 and 130 is 800 g / m ^{2, which is particularly preferable.} Is shown in the graph of the result obtained by computer simulation. Assuming that the basis weight of the second fiber layer 120 is Y (g / m ² ), the basis weight Y is a value obtained by subtracting ^{800 g / m 2} from the basis weight of the silencer 1. Here, the blending ratio of the main fibers 115 and 135 in the fiber layers 110 and 130 is set to a particularly preferable 70% by weight, and the blending ratio of the thermoplastic fibers 126 in the second fiber layer 120 is set to a particularly preferable 100% by weight. There is. In FIG. 8, the horizontal axis is the basis weight of the silencer 1 (g / m ² ), and the vertical axis is the recess amount L0 (mm). The ten curves shown in FIG. 8 show the silencer 1 thickness T0 (unit: mm) of 10, 15, 20, 25, 30, 35, 40, 45, 50 in order from the bottom to the top. , And the correspondence when changing to 60 is shown.

Here, when the dent amount L0 when a load F of 50 N is applied to the thickness direction D3 to the disk 500 having a diameter of 50 mm placed on the first molding surface 11 of the silencer 1 is 15 mm or less, an appropriate compressive strength is obtained. Is obtained. For this reason, the thickness T0 of the silencer itself is preferably 20 mm or more. The basis weight Y at which the dent amount L0 is 15 mm for each curve having a thickness T0 of 20 to 60 mm is the minimum basis weight required for the second fiber layer 120.

FIG. 9 shows a graph of the correspondence relationship CO1 and CO2 between the thickness T0 of the silencer 1 and the basis weight Y of the second fiber layer 120. In FIG. 9, the horizontal axis is the silencer thickness T0 (mm), and the vertical axis is the basis weight Y (g / m ² ) of the second fiber layer. The correspondence CO1 shown in FIG. 9 shows the minimum basis weight obtained from the basis weight Y in which the dent amount L0 is 15 mm for each curve having a thickness T0 of 20 to 60 mm in FIG. The correspondence CO2 shown in FIG. 9 shows the minimum basis weight obtained from the basis weight Y in which the dent amount L0 is 15 mm when the material of the second fiber layer 120 is replaced with the material of the fiber layers 110 and 130. .. When the thickness T0 of the silencer 1 is X (mm) and the basis weight of the second fiber layer 120 is Y (g / m ² ), the correspondence CO1 is
^{Y = 1.068 · X 2 -23.12 ·} X + 176.4 ... (1)
It is represented by. In addition, the correspondence relationship CO2 is
^{Y = 1.755 · X 2 -24.97 ·} X-48.35 ... (2)
It is represented by.

According to the correspondence CO1 shown in FIG. 9, the basis weight Y of the second fiber layer 120 is within the range ^{where the density of the silencer 1 is 0.10 g / cm 3 or less.
Y ≧ 1.068 · X 2 -23.12 ·} X + 176.4 ... (3)
Is preferable.
Although the basis weight Y of the second fiber layer is limited by the density of the silencer 1 being 0.10 g / cm ³ or less, the basis weight Y of the second fiber layer is determined by the correspondence CO2 shown in FIG.
^{Y <1.755 · X 2 -24.97 ·} X-48.35 ... (4)
Is preferable.

Actually, clothing anti-hair fibers are used for the main fibers 115 and 135, PET resin fibers having a melting point of 100 to 120 ° C. are used for the thermoplastic fibers 116, 126 and 136, and the density of the sample SA of the silencer 1 is 0.10 g / cm. ^The sample SA was prototyped so that the thickness X of the sample SA and the texture Y of the second fiber layer 120 satisfy the above inequality (3). The dent amount L0 of the obtained sample SA was 15 mm or less, and the sample SA had an appropriate compressive strength. Further, even when the third fiber layer 130 is not provided, a sample SA having an appropriate compressive strength of L0 ≦ 15 mm can be produced. Further, conjugate fibers having a core made of PET resin and a sheath made of PE resin having a melting point of 130 to 140 ° C. are used for the thermoplastic fibers 116, 126, 136, or the second fiber layer 120 is in the range of 50% by weight or less. The auxiliary fibers 125 are added, the main fibers 115 and 135 of the fiber layers 110 and 130 are changed in the range of 60 to 99% by weight, and the combined texture of the fiber layers 110 and 130 is in the range of 600 to 1000 g / m ² . Even if it is changed, a sample SA having L0 ≦ 15 mm having an appropriate compressive strength can be produced.

If the basis weight of the entire silencer 1 is Ya (g / m ² ), the basis weights of the fiber layers 110 and 130 are added to the basis weight Y of the second fiber layer 120.
^{Ya ≧ 1.068 · X 2 -23.12 ·} X + 976.4 ... (5)
Is preferable. Further, although the basis weight Ya is limited by the density of the silencer 1 being 0.10 g / cm ^{3 or less,
Y <1.755 · X 2 -24.97 ·} X + 751.7 ... (6)
Is preferable.

(3) Specific example of manufacturing method of automobile silencer:
FIG. 10 schematically shows an example of a silencer manufacturing apparatus for manufacturing a silencer 1 for an automobile. The upper part of FIG. 10 illustrates a schematic plan view of the silencer manufacturing apparatus 400 as viewed from above. FIG. 11 schematically illustrates the vertical end face of the press molding machine 200.

The silencer manufacturing apparatus 400 shown in FIG. 10 includes a first fiber supply section 410 that feeds the fiber F1 downward, a second fiber supply section 420 that feeds the fiber F2 downward, a third fiber supply section 430 that feeds the fiber F3 downward, and a conveyor. It has 440, a control unit 450, and a press molding machine 200. Here, the fiber F1 becomes the fiber 114 of the first fiber layer 110, the fiber F2 becomes the fiber 124 of the second fiber layer 120, and the fiber F3 becomes the fiber 134 of the third fiber layer 130. When forming the silencer 1 without the third fiber layer 130, the third fiber supply unit 430 may be omitted.

The first fiber supply unit 410 defibrate and mix the raw yarn for the fiber F1 and supply the fiber F1 onto the conveyor 440 moving in the moving direction D4 so that the thickness and the basis weight are substantially constant. The feed fiber layer 310 is formed. Therefore, the first fiber supply step S1 is mainly carried out by the first fiber supply unit 410 and the conveyor 440. The first supply fiber layer 310 is a first fiber layer 110 having a substantially flat first molded surface 11.

The second fiber supply unit 420 arranged on the downstream side of the first fiber supply unit 410 in the movement direction D4 defibrate and mix the raw yarn for the fiber F2, and the first supply fiber layer moves in the movement direction D4. The fiber F2 is supplied onto the 310 so as to have a partially different thickness and basis weight to form the second supply fiber layer 320. Therefore, the second fiber supply step S2 is mainly carried out by the second fiber supply unit 420 and the conveyor 440. The second supply fiber layer 320 becomes a second fiber layer 120 having an adhesive surface 121. The second fiber supply section 420 shown in FIG. 10 has a plurality of split fiber supply sections 425 in which the supply points of the fibers F2 are different from each other in the width direction D5 of the conveyor 440. FIG. 10 shows that the second fiber supply unit 420 is divided into the divided fiber supply units # 1 to # 10, but the number of the divided fiber supply units 425 installed in the second fiber supply unit 420. Is not limited to 10. Each split fiber supply unit 425 has a function of measuring the fiber F2. From each split fiber supply unit 425, an arbitrary amount of fiber F2 can be deposited at an arbitrary position on the upper surface of the first supply fiber layer 310 transferred by the conveyor 440.

The third fiber supply unit 430 arranged on the downstream side of the second fiber supply unit 420 in the movement direction D4 defibrate and mix the raw yarn for the fiber F3, and the supply fiber layer 310, which moves in the movement direction D4, The fiber F3 is supplied onto the 320 so that the thickness and the texture are substantially constant to form the third supply fiber layer 330. That is, the fiber F3 is deposited on the second supply fiber layer 320 and the first supply fiber layer 310 without the fiber F2 of the second supply fiber layer 320. Therefore, the third fiber supply step S3 is mainly carried out by the third fiber supply unit 430 and the conveyor 440. The third supply fiber layer 330 becomes a third fiber layer 130 having a second molding surface 12.

The conveyor 440 carries the fiber assembly 300 including the supply fiber layers 310, 320, 330 and transfers the fiber assembly 300 in the moving direction D4. A belt conveyor or the like can be used for the conveyor 440. When a large number of ventilation holes are formed in the belt of the belt conveyor, it is suitable for preheating the fiber assembly 300 to a temperature slightly higher than the melting point of, for example, the thermoplastic fibers 116, 126, 136 by hot air heating or the like. ..

The control unit 450 controls the moving speed V1 of the conveyor 440, the supply speeds of the fibers F1 and F3 from the fiber supply units 410 and 430, the supply speed V2 of the fibers F2 from each divided fiber supply unit 425, and the like. In particular, the control unit 450 controls to supply the fiber F2 only to the preset region on the first supply fiber layer 310, and further controls the supply amount of the fiber F2 in the region to supply the fiber F2. The control unit 450 variably controls the basis weight of the fibers F2 supplied from the split fiber supply unit 425 onto the first supply fiber layer 310 in units of the split fiber supply unit 425 according to a sequence constituting the control program.

The fiber aggregate 300 formed through the fiber supply steps S1, S2, and S3 is carried into the press molding machine 200 and press-molded (molding step S5). The fiber assembly 300 may be preheated before the molding step S5 (preheating step S4). In the preheating step S4, the fiber aggregate 300 is carried into a heater such as a suction heater (hot air circulation heater) and preheated to a temperature slightly higher than the melting point of, for example, the thermoplastic fibers 116, 126, 136 by hot air heating or the like. You may. In order to increase the amount of heat during preheating, radiant heating by an infrared heater may be performed at the same time in addition to heating by a suction heater. Of course, heating without using a suction heater is also possible. Further, in the preheating step S4, the preform may be formed by preforming according to the shape of the silencer 1.

The mat-shaped or preform-shaped fiber assembly 300 is carried into a press molding machine 200 as illustrated in FIG. In the press molding machine 200 shown in FIG. 11, the upper mold 212 and the lower mold 214 constituting the press molding mold 210 are provided so as to be close to each other and separable from each other. The upper mold 212 is a mold having a mold surface 213 on the facing surface that matches the shape of the silencer 1 on the vehicle body panel 80 side. The lower mold 214 is a mold having a mold surface 215 on the facing surface that matches the shape of the silencer 1 on the carpet 20 side. The press molding is preferably a hot press with heating, but may be a cold press without heating.

The fiber assembly 300 is arranged on the lower mold 214 (press molding step P1), and when both molds 212 and 214 are close to each other, the silencer 1 before trimming is press molded (press molding step P2). As a result, when the first fiber layer 110 is formed from the first supply fiber layer 310, the second fiber layer 120 is formed from the second supply fiber layer 320, and the fiber assembly 300 has the third supply fiber layer 330. The third fiber layer 130 is formed from the third supply fiber layer 330. The first molding surface 11 is formed on the first fiber layer 110. The second fiber layer 120 is integrated with the first fiber layer 110, and is integrated with the third fiber layer 130 when there is a third supply fiber layer 330. When there is a third supply fiber layer 330, a second molding surface 12 is formed on the third fiber layer 130. When there is no third supply fiber layer 330, the second molded surface 12 is formed on the second fiber layer 120 and the fiber-free portion of the second fiber layer 120 in the first fiber layer 110.

After cooling, the silencer 1 before trimming is taken out from the press molding machine 200 and carried into the outer peripheral cutting machine, and the outer circumference is cut. As the cutting method, cutting with a cutting blade, water jet cutting, manual cutting with a cutter, or the like can be adopted. Further, if necessary, a hole penetrating the silencer 1 in the thickness direction D3 may be formed.

(4) Actions and effects of automobile silencers according to specific examples:
As described above, since the press-molded second fiber layer 120 contains 50% by weight or more of the thermoplastic fibers 126, the thermoplastic fibers 126 fused to each other give high rigidity to the second fiber layer 120. ing. It is presumed that this keeps the compression strength of the silencer 1 even if the silencer 1 is made lighter. Further, the press-molded fiber layers 110 and 130 contain 60% by weight or more of the main fibers 115 and 135 containing a non-melting component, thereby giving the fiber layers 110 and 130 flexibility. It is presumed that this improves the feel of the silencer 1. The press-molded fiber layers 110 and 130 contain 1% by weight or more of the thermoplastic fibers 116 and 136, so that the shapes of the fiber layers 110 and 130 are maintained.
In the silencer 1 of this specific example, the second fiber layer 120 having a large weight ratio of the thermoplastic fiber is combined with the fiber layers 110 and 130 containing a large amount of the main fibers 115 and 135 containing the non-melting component. Appropriate compression strength is obtained even if the weight is reduced. This is because, in the press-molded silencer 1, an appropriate compressive strength can be obtained even if the weight is reduced by combining the appropriate rigidity of the second fiber layer 120 and the flexible feel of the fiber layers 110 and 130. It is presumed.

Further, the second fiber layer 120 in which the weight ratio of the thermoplastic fiber is increased to the fiber layers 110 and 130 is combined, and the thickness X mm of the silencer 1 and the basis weight Yg / m ² of the second fiber layer 120 are the above inequality. The silencer 1 has a feature that the relationship of (3) is satisfied and the dent amount L0 is 15 mm or less. As described above, many weight ratio of thermoplastic fibers 126 of the second fiber layer 120 which is press-formed, a basis weight Y of the second fiber layer 120 is ^{Y ≧ 1.068 · X 2 -23.12 ·} X + 176.4 Therefore, the thermoplastic fibers 126 fused to each other give high rigidity to the second fiber layer 120. It is presumed that this keeps the compression strength of the silencer 1 even if the silencer 1 is made lighter. Further, since the weight ratio of the thermoplastic fibers 116 of the press-molded fiber layers 110 and 130 is small, the fiber layers 110 and 130 are given flexibility. It is presumed that this improves the feel of the silencer 1. Further, when the recess amount L0 of the silencer 1 is 15 mm or less, the feel of the silencer 1 is further improved.
Due to the above characteristics, the silencer 1 has an appropriate compressive strength even ^{when the density is 0.10 g / cm 3 or less.} Therefore, the silencer 1 of this specific example can obtain an appropriate compression strength even if the weight is reduced.

In the silencer 1 having the above characteristics, the second fiber layer 120 may contain the thermoplastic fiber 126 having a weight ratio larger than the weight ratio of the thermoplastic fiber 116 contained in the first fiber layer 110. .. Therefore, in the silencer 1 having the above characteristics, the thermoplastic fibers 116 and 136 of the fiber layers 110 and 130 may be more than 40% by weight, and the thermoplastic fibers 126 of the second fiber layer 120 may be 50% by weight. It may be less than.

(5) Modification example:
Various modifications of the present invention can be considered.
For example, automobile silencers to which the present invention can be applied include, in addition to floor silencers for passenger compartments, silencers for luggage compartments, silencers for doors, silencers for ceilings, dash silencers, silencers for engines, and fenders. It may be a silencer, etc.

(6) Conclusion:
As described above, according to the present invention, it is possible to provide a technique such as an automobile silencer capable of obtaining an appropriate compression strength even if the weight is reduced, in various aspects. Of course, the above-mentioned basic actions and effects can be obtained even with a technique consisting of only the constituent requirements according to the independent claims.
In addition, the configurations disclosed in the above-mentioned examples are mutually replaced or the combinations are changed, the known techniques and the respective configurations disclosed in the above-mentioned examples are mutually replaced or the combinations are changed. It is also possible to implement the above-mentioned configuration. The present invention also includes these configurations and the like.

1 ... silencer, 10 ... surface, 11 ... first molding surface, 12 ... second molding surface,
20 ... Carpet (skin material), 80 ... Body panel,
110 ... first fiber layer, 114 ... fiber, 115 ... main fiber, 116 ... thermoplastic fiber,
120 ... Second fiber layer, 124 ... Fiber, 125 ... Secondary fiber, 126 ... Thermoplastic fiber,
130 ... Third fiber layer, 134 ... Fiber, 135 ... Main fiber, 136 ... Thermoplastic fiber,
500 ... disk,
D3 ... Thickness direction,
L0 ... Amount of dent,
T0 ... Thickness of silencer.

Claims (4)

A press-molded silencer for automobiles
A first fiber layer containing 60 to 99% by weight of a main fiber containing a non-melted component and 1 to 40% by weight of a thermoplastic fiber.
A second fiber layer containing 50 to 100% by weight of thermoplastic fibers,
Including silencer. The silencer has a thickness of 20 mm or more and has a thickness of 20 mm or more.
The density of the silencer is 0.10 g / cm ³ or less.
The thickness of the silencer and X mm, when the basis weight of the second fiber layer was Yg / m ^2, the basis weight Y is ^{Y ≧ 1.068 · X 2 -23.12 ·} X + 176.4,
The silencer according to claim 1, wherein when a load of 50 N is applied to a disk having a diameter of 50 mm placed on the surface of the silencer in the thickness direction of the silencer, the distance that the silencer is recessed is 15 mm or less. A third fiber layer containing 60 to 99% by weight of a main fiber containing a non-molten component and 1 to 40% by weight of a thermoplastic fiber is further contained.
The silencer according to claim 1 or 2, wherein the second fiber layer is located between the first fiber layer and the third fiber layer. A press-molded silencer for automobiles
The first fiber layer containing the thermoplastic fiber and the second fiber layer containing the thermoplastic fiber having a weight ratio higher than the weight ratio of the thermoplastic fiber contained in the first fiber layer are included.
The silencer has a thickness of 20 mm or more and has a thickness of 20 mm or more.
The density of the silencer is 0.10 g / cm ³ or less.
The thickness of the silencer and X mm, when the basis weight of the second fiber layer was Yg / m ^2, the basis weight Y is ^{Y ≧ 1.068 · X 2 -23.12 ·} X + 176.4,
A silencer having a distance of 15 mm or less in which the silencer is recessed when a load of 50 N is applied to a disk having a diameter of 50 mm placed on the surface of the silencer in the thickness direction of the silencer.

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