JP5307676B2 - Duct and manufacturing method thereof - Google Patents

Description

  The present invention relates to a duct formed from a nonwoven fabric containing a thermoplastic resin or a thermosetting resin, and a method for producing the same.

  2. Description of the Related Art Conventionally, there are air intake ducts, air conditioning ducts, and the like in automobiles that are made of a nonwoven fabric containing a thermoplastic resin. As shown in FIG. 6, the manufacturing method of the duct constituted by the nonwoven fabric containing the thermoplastic resin is first formed by heating and compressing the nonwoven fabric 51 with the concave mold 71 and the convex mold 73 to form a mold surface shape. A duct half 81 having a portion 83 is formed. At the time of the heat compression, the flange portion 83 is shaped in the compressed state by compressing the nonwoven fabric between the concave mold 71 and the convex mold 73. Next, as shown in FIG. 7, the duct halves 81 are overlapped with each other, and the flange portion 83 is joined by welding or the like to form a tubular shape, thereby obtaining a duct 80 as shown in FIG. The flange portion 83 is required to have a width (projection length) of about 3 to 10 mm in order to ensure the bonding strength of the duct half 81.

  However, the duct 80 formed by joining the duct half body 81 made of the nonwoven fabric with the flange portion 83 is in a hard state where the flange portion 83 is heated and compressed between the concave shape and the convex shape and the fibers are dense. When it is arranged in an engine room as an intake duct for an automobile, there is a problem that the flange portion 83 rubs against surrounding parts, devices, etc. due to vibrations and generates abnormal noise. In addition, since various parts and devices are present in the engine room and the space for arranging the ducts is limited, the ducts are arranged separately from the parts and devices, and the flange portion 83 is surrounded by surrounding parts and devices due to vibration or the like. I couldn't even get out of contact. Further, if the width of the flange portion 83 is reduced (the protruding length is shortened) for the purpose of increasing the distance between the flange portion 83 and the surrounding parts and devices, the joint strength of the duct half 81 is insufficient. On the other hand, when the pipe diameter of the duct is reduced, the opening area of the duct is reduced, the flow rate of the gas is reduced, and the function of the duct is reduced. Therefore, the width of the flange portion 83 is reduced ( Neither the projection length was shortened nor the duct diameter was reduced.

JP-A-11-343938 JP 2007-176316 A JP 2008-20082 A

  The present invention has been made in view of the above points, and it is an object of the present invention to provide a duct that is less likely to generate abnormal noise when the flange portion of the duct formed from a nonwoven fabric rubs against other parts and the like, and a method for manufacturing the same. .

  The invention according to claim 1 is a duct in which duct halves made of a nonwoven fabric containing a thermoplastic resin or a thermosetting resin are overlapped with each other and joined by flange portions formed on both sides of the duct half. The base portion of the flange portion is made of a compressed state of the nonwoven fabric, and the tip portion is made of an uncompressed state of the nonwoven fabric.

  The invention of claim 2 is a method in which a non-woven fabric containing a thermoplastic resin or a thermosetting resin is heated and compressed between a concave mold and a convex mold to form duct halves with protruding flanges on both sides, and the duct halves are overlapped. In addition, in the method of manufacturing a duct for joining the flange portion together, the non-woven fabric is compressed at a position corresponding to the base portion of the flange portion when the non-woven fabric is heated and compressed by the concave mold and the convex mold. The non-compressed non-woven fabric is formed into a duct half in which the base portion of the flange portion is in a compressed state of the non-woven fabric and the distal end portion of the flange portion is in an uncompressed state of the non-woven fabric. By joining the flange portions between the bodies, the base portion of the flange portion is formed of a compressed state of the non-woven fabric, and the tip portion is formed of a non-compressed state of the non-woven fabric. It is characterized in.

  In the duct of the present invention, since the non-woven fabric is in an uncompressed state at the front end of the flange portion, the front end of the flange portion is soft and has a cushioning property inherent to the non-woven fabric. Therefore, the duct according to the present invention is arranged in an engine room of an automobile, and even if the tip of the flange portion rubs against other objects due to vibration of the automobile or the like, the tip of the flange portion is good at that time. Absorbing noise can be prevented by exhibiting buffering properties. In addition, the duct of the present invention does not need to increase the distance between the other object and the flange end by reducing the width of the flange or reducing the duct diameter from the viewpoint of preventing abnormal noise. In addition, it is possible to ensure a sufficient joint strength in the flange portion and a sufficient opening area of the duct.

  In addition, according to the manufacturing method of the present invention, even if the tip of the flange portion rubs against other objects due to vibration or the like, the tip of the flange portion exhibits a good cushioning property at that time, and abnormal noise is generated. A duct that can be prevented can be easily manufactured. In addition, according to the manufacturing method of the present invention, it is not necessary to reduce the width of the flange portion or the pipe diameter of the duct in order to prevent abnormal noise. A duct that can secure a large opening area can be manufactured.

It is a perspective view of the duct of one embodiment in the present invention. It is 2-2 sectional drawing of FIG. It is sectional drawing which shows the heat compression of the nonwoven fabric in one Embodiment of the manufacturing method of this invention. It is sectional drawing which shows joining of the flange part of the duct half body in the embodiment. It is sectional drawing of the duct manufactured by the same embodiment. It is sectional drawing which shows the heat compression of the nonwoven fabric in the conventional manufacturing method. It is sectional drawing which shows joining of the flange part of the duct half body in the conventional manufacturing method. It is sectional drawing of the duct manufactured by the conventional manufacturing method.

Hereinafter, a duct and a method for manufacturing the duct according to an embodiment of the present invention will be described with reference to the drawings.
The duct 10 shown in FIG. 1 is obtained by overlapping and joining the duct halves 11 to each other. The duct 10 has a rectangular tube shape in this embodiment, but may have a circular tube shape or other tube shapes.

  The duct half body 11 is made of a nonwoven fabric containing a thermoplastic resin or a thermosetting resin, and includes a half-pipe half body portion 13 and flange portions 15 formed on both sides of the half body portion 13. ing. The duct half body 11 is obtained by heating and compressing a nonwoven fabric containing a thermoplastic resin or a thermosetting resin between a concave shape and a convex shape. In addition, the nonwoven fabric containing the thermoplastic resin or the thermosetting resin is shaped into a mold surface shape by heat compression using a concave mold and a convex mold, and the shape is fixed by subsequent natural cooling or the like.

  As the thermoplastic resin or thermosetting resin constituting the nonwoven fabric, a composite thermoplastic resin fiber composed of a high melting point resin portion such as polyester or polypropylene and a low melting point resin portion such as polyethylene is preferable. The composite thermoplastic resin fiber has a core-sheath structure in which the center core is made of a high-melting resin and the outer sheath is made of a low-melting resin, or the high-melting resin part and the low-melting resin An example in which the parts are arranged can be mentioned. The nonwoven fabric may be a mixture of high melting point resin fibers and low melting point resin. Furthermore, the nonwoven fabric may be composed of both thermoplastic resin fibers and other fibers.

  The flange portion 15 is a portion used for joining the duct halves 11, and is formed in the overlapping portion of the duct halves 11 along the length direction of the duct halves 11. The flange portions 15 of the duct halves 11 are overlapped and joined by welding, an adhesive, or the like. As shown in FIG. 2, the flange portion 15 protrudes outward from the overlapping portion of the half body portion 13, and the base portion 16 on the half body portion 13 side is compressed from the nonwoven fabric. Thus, the tip 17 is made of the non-compressed state of the nonwoven fabric.

  The base 16 is formed by compressing the nonwoven fabric in a softened state during heat compression of the concave and convex nonwoven fabric and fixing the compressed state by subsequent natural cooling or the like, and the fibers are denser than the nonwoven fabric before heat compression. It has become. The thickness of the base portion 16 is appropriately determined, but in order to obtain sufficient bonding strength, about 2/3 to 1/5 of the thickness of the nonwoven fabric before heat compression molding is preferable. The width (protrusion length from the half body portion 13) a of the base portion 16 in the compressed state is appropriately determined, but is preferably about 2 to 5 mm in order to obtain sufficient bonding strength.

  On the other hand, the tip portion 17 is non-compressed at the time of heat compression of the nonwoven fabric of the concave shape and the convex shape, has the softness and cushioning property of the nonwoven fabric before heat compression molding, and is nonwoven fabric than the base portion 16. The fibers are rough and are thicker than the base 16. The width (protrusion length from the half body portion 13) b of the tip portion 17 in the uncompressed state is appropriately determined, but the outer shape of the duct 10 is not excessively large and sufficient buffering properties are obtained. Is preferably about 1 to 5 mm.

  Since the nonwoven fabric is in an uncompressed state at the distal end portion 17 of the flange portion 15, the duct 10 is soft at the distal end of the flange portion 15 and has a cushioning property inherent to the nonwoven fabric. Even if it rubs against an object, the front end of the flange portion 15 exhibits a good cushioning property at that time, and the generation of abnormal noise can be prevented. Further, even if the duct 10 may cause condensation on the outer surface during use, the duct 10 receives the condensed water on the outer surface of the duct 10 at the base portion 16 of the flange portion 15 or is impregnated and held at the tip portion 17 of the flange portion 15. Thus, the effect of making it difficult to drop from the duct 10 is also obtained. That is, since the base portion 16 of the flange portion 15 has a groove shape between the half body portion 13 and the tip portion 17 of the flange portion 15, one of the flange portions 15 on both sides of the duct is on the upper side and the other is the lower side. When the duct 10 is installed so as to be, the dew condensation water that has moved downward along the outer surface of the duct 10 can be received by the groove-shaped base 16 in the flange portion 15. Further, when the duct 10 is installed with the flange portions 15 on both sides of the duct being horizontal as shown in FIG. 1, dew condensation water can be received by the groove-like base portion 16 in the flange portion 15 of the upper duct half. Furthermore, even if the flanges on both sides of the duct are either in the vertical direction or in the horizontal direction, the tip part 17 of the flange part 15 is in a non-compressed state as described above, and the fibers are dense. Therefore, the condensed water is easily impregnated and easily retained.

An embodiment of a method for manufacturing the duct 10 will be described. The manufacturing method of a duct consists of the heating compression process of a nonwoven fabric, and the joining process of a duct half body.
In the nonwoven fabric heating and compressing step, as shown in FIG. 3 (3A), the nonwoven fabric 31 containing the thermoplastic resin or the thermosetting resin is disposed between the concave mold 21 and the convex mold 25, and (3B) in FIG. As shown in the figure, the duct half body 11 is formed by sandwiching the concave mold 21 and the convex mold 25 and performing heat compression molding, and shaping the nonwoven fabric 31 into a mold surface shape.

  The concave mold 21 has a mold surface 22 adapted to the outer surface shape of the duct half body 11. The mold surface 22 includes a half body portion forming portion 23 corresponding to the half body portion 13 and a flange portion forming portion 24 corresponding to the flange portion 15. On the other hand, the convex mold 25 has a mold surface 26 that matches the shape of the inner surface of the duct half body 11. The mold surface 26 includes a half body portion forming portion 27 corresponding to the half body portion 13 and a flange portion forming portion 28 corresponding to the flange portion 15. The distance between the mold surfaces when the concave mold 21 and the convex mold 22 are closed is set to a value corresponding to the thickness of the duct half body 11.

  A flange portion forming portion 24 in the mold surface 22 of the concave mold 21 and a flange portion forming portion 28 in the mold surface 26 of the convex mold 25 are portions 24 a and 28 a corresponding to the base portion 16 of the flange portion 15 in the duct half body 11. And portions 24 b and 28 b corresponding to the front end portion 17 of the flange portion 15 in the duct half body 11. The portions 24a and 28a corresponding to the base portion of the flange portion have a space between the mold surfaces smaller than the thickness of the nonwoven fabric 31 so that the nonwoven fabric 31 is compressed by a predetermined amount when the concave mold 21 and the convex mold 25 are closed in the heat compression molding process. It is set to small. As described above, the distance between the portions 24a and 28a corresponding to the base portion of the flange portion at the time of the closing, that is, the degree of compression of the nonwoven fabric is 2/3 of the thickness of the nonwoven fabric 31 before heat compression molding before heat compression. About 1/5 is preferable. On the other hand, the portions 24b and 28b corresponding to the front ends of the flange portions in the flange portion forming portions 24 and 28 do not compress the nonwoven fabric 31 when the concave mold 21 and the convex mold 25 are closed in the heat compression molding process. The space between the mold surfaces is set to be equal to or greater than the thickness of the nonwoven fabric 31 before heating and compression. In the illustrated example, the portion 24b corresponding to the front end portion of the flange portion in the concave mold 21 is recessed, whereas the portion 28b corresponding to the front end portion of the flange portion in the convex mold 25 is flat. However, the opposite may be possible, or the portions 24b and 28b corresponding to the tip portions of the flange portions of the concave mold 21 and the convex mold 25 may be recessed.

  The heating temperature of the nonwoven fabric 31 at the time of the heat compression molding is a temperature at which the nonwoven fabric 31 can be heat compression molded (shaped), for example, a thermoplastic resin or a thermosetting resin constituting the nonwoven fabric 31 is a composite thermoplastic resin. In the case of fibers, the temperature is higher than the melting point of the low melting point resin and lower than that of the high melting point resin. The nonwoven fabric 31 may be heated by a heating device outside the mold, or heating means are provided on the concave mold 21 and the convex mold 25 to heat the mold surfaces 23 and 26, and the heated mold surfaces 23 and 26 are used. The nonwoven fabric 31 may be heated.

  After the heat compression molding step, the concave mold 21 and the convex mold 25 are separated to take out a molded product, and unnecessary parts are cut out as necessary to obtain the duct half body 11. The duct half 11 thus obtained has a base portion 16 of the flange portion 15 in a compressed state of a nonwoven fabric, while a distal end portion 17 of the flange portion 15 has a non-compressed state of the nonwoven fabric. The other duct half body 11 is also formed by the same heat compression molding process as described above.

  In the duct half joining step, as shown in FIG. 4, the duct halves 11 are overlapped with each other and the flange portions 15 are joined to obtain the duct 10 shown in FIG. 5. The flange portion 15 is joined by welding or an adhesive. In addition, even if the base part 16 of the said flange part 15 piled up is pressed with a heating apparatus from both sides, the base part 16 is joined, or an adhesive is applied to the base part 16 of the said flange part 15, and the said base part 16 is joined. Good. Thus, if the base portion 16 in the compressed state in the flange portion 15 is joined and the tip portion 17 in the non-compressed state is unjoined, the flexibility and cushioning properties of the tip portion 17 of the flange portion 15 become better, When the front end of the flange portion 15 rubs against another object, the generation of abnormal noise can be prevented more reliably.

Non-woven fabric (thickness 5 mm, weight per unit area) formed of a core-sheath composite thermoplastic resin fiber (2.0 denier) consisting of polypropylene (melting point 165 ° C.) in the center and polyethylene (melting point 130 ° C.) in the sheath portion 700 g / m ² ) is cut into 1000 × 1000 mm, heated with a heater at a temperature of 140 ° C., placed between the concave mold and the convex mold shown in FIG. 3, the concave mold and the convex mold are closed, and the nonwoven fabric is heat compression molded. Thereafter, unnecessary portions were cut off to form one duct half. Similarly, the other half of the duct was formed.

  The concave mold surface forming the half body portion in the concave mold has a size of 40 mm × 75 mm × 600 (length) mm, and the mold surface forming the half body portion in the convex mold is a closed mold. It is sometimes dimensioned to form a 2 mm shaping gap between the concave mold surface. Further, the width of the mold surface corresponding to the base of the flange portion of the duct half in the concave and convex molds (the width corresponding to the width a of the base of the flange portion in FIG. 2) is 3 mm, The width of the mold surface corresponding to the front end portion of the flange portion (the width corresponding to the width b of the front end portion of the flange portion in FIG. 2) is 5 mm. Further, the concave mold and the convex mold are arranged so that the distance between the base of the flange half of the duct half and the corresponding mold surface in the concave mold and the convex mold is 1 mm when closed, and the flange half of the duct half The distance between the tip and the corresponding mold surface was set to 5 mm. During the heat compression molding, the mold temperature of the concave mold and the convex mold was set to 30 to 40 ° C.

  The duct half obtained in this way has outward flanges on the sides on both sides, the flange base is in a compressed state, and the flange end is in an uncompressed state. Become. Next, the two duct halves are made to face each other with their inner surfaces facing each other, and the side flange portions are overlapped, and the plate-like heating member (at 170 ° C.) whose tip is equal to the width of the base portion of the flange portion. The base part of the flange part was welded and joined together, and the two duct halves were integrated into a tubular shape to produce the duct 10 shown in FIG. The duct 10 obtained in this way has a base portion of the flange portion in a compressed state and a tip portion of the flange portion in an uncompressed state, the tip of the flange portion is soft, and the original cushioning property of the nonwoven fabric is obtained. Had.

DESCRIPTION OF SYMBOLS 10 Duct 11 Duct half body 13 Half body main part 15 Flange part 16 Flange part base 17 Flange part tip part 21 Concave type 22 Concave mold surface 23 Half body part forming part in concave mold surface 24 Concave part mold surface Flange part forming part 24a Part corresponding to the base part of the flange part 24b Part corresponding to the tip part of the flange part 25 Convex 26 Convex mold surface 27 Half body part forming part 28 in concave mold surface 28 Convex mold surface Flange portion forming portion 28a portion corresponding to the base portion of the flange portion 28b portion corresponding to the tip portion of the flange portion 31 non-woven fabric

Claims (2)

In the duct where the duct halves composed of a thermoplastic resin or a non-woven fabric containing a thermosetting resin are overlapped with each other and joined by flange portions formed on both sides of the duct halves,
A duct characterized in that a base portion of the flange portion is in a compressed state of the nonwoven fabric, and a tip portion is in an uncompressed state of the nonwoven fabric. A non-woven fabric containing a thermoplastic resin or a thermosetting resin is heated and compressed between a concave mold and a convex mold to form a duct half with protruding flanges on both sides, and the duct halves are overlapped to join the flange. In the method of manufacturing a duct,
When the nonwoven fabric is heated and compressed by the concave mold and the convex mold, the nonwoven fabric is compressed at a position corresponding to the base of the flange portion, and the nonwoven fabric is uncompressed on the outer side of the compressed portion, thereby the flange portion. The base portion of the non-compressed nonwoven fabric and the leading end of the flange portion form a non-compressed duct half body,
By joining the flange portions of the duct halves, a base portion of the flange portion is formed of a compressed state of the nonwoven fabric, and a tip portion is formed of a non-compressed state of the nonwoven fabric. A method of manufacturing a duct.

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