Soundproof cover and method for manufacturing the same

Abstract

To provide a soundproof cover with a highly durable connection. [Solution] The soundproof cover 10 is positioned to surround a sound source and suppress the leakage of sound emitted from the sound source to the outside. The soundproof cover 10 is formed at least in part from a soft foamed resin and comprises a plurality of cover bodies 12 that surround the sound source, connecting parts 14 and 16 provided on the cover bodies 12 that connect the cover bodies 12 to each other, and three-dimensional mesh bodies 18 and 20 embedded in the connecting parts 14 and 16. The soft foamed resin is arranged within the mesh of the three-dimensional mesh bodies 16 and 18.

Description

Technical Field

[0001] This invention relates to a soundproof cover and a method for manufacturing the same.

Background Art

[0002] As disclosed in Patent Document 1, a compressor cover configured to be openable and closable by bending a cover body made of foamed urethane at a hinge portion has been proposed to protect a compressor from collision with foreign objects.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Since the hinge portion of Patent Document 1 is formed of foamed urethane, there is a concern about insufficient strength.

[0005] In view of the above problems in the prior art, the present invention has been proposed to preferably solve these problems, and an object thereof is to provide a soundproof cover having a connection portion with excellent strength and a method for manufacturing the same.

Means for Solving the Problems

[0006] A first aspect of the soundproof cover according to the present invention is a plurality of cover bodies at least partially formed of a soft foamed resin and surrounding a sound source, a connection portion provided on the cover body and connecting the cover bodies to each other, and a three-dimensional mesh body embedded in the connection portion, and the gist is that the foamed resin is disposed within the mesh of the three-dimensional mesh body.

[0007] A second embodiment of the soundproof cover according to the present invention is, in the first embodiment, The three-dimensional mesh body may be made of de-membrane urethane foam.

[0008] A third aspect of the soundproof cover according to the present invention is, in the first or second aspect, The connecting portion may be a hinge that connects the cover bodies in a way that allows them to be opened and closed.

[0009] A fourth aspect of the soundproof cover according to the present invention is, in the first or second aspect, The connecting portion is a contact portion that comes into contact with each other when the cover bodies are closed, and may have a through hole that penetrates the embedded three-dimensional mesh body.

[0010] A fifth aspect of the soundproof cover according to the present invention is, in the second aspect described above, The number of cells in the defilmed urethane foam may be in the range of 6 cells / 25 mm to 20 cells / 25 mm.

[0011] A first aspect of the method for manufacturing a soundproof cover according to the present invention is: A method for manufacturing a soundproof cover comprising a plurality of cover bodies surrounding a sound source, and connecting parts provided on the cover bodies for connecting the cover bodies to each other, A three-dimensional mesh body is placed in the part of the mold used to form the cover body and the connecting part, The gist of this method is to inject foamed resin raw material into the mold to form the cover body, which is at least partially made of soft foamed resin, and to impregnate the mesh of the three-dimensional mesh body with the foamed resin raw material to form the connecting portion which is made of foamed resin. [Effects of the Invention]

[0012] The soundproof cover according to the present invention has a connection part with excellent strength. According to the method for manufacturing a soundproof cover of the present invention, a soundproof cover having a connection part with excellent strength can be obtained. [Brief explanation of the drawing]

[0013] [Figure 1] It is a schematic perspective view showing the soundproof cover according to the embodiment in a closed state. [Figure 2] It is a plan view showing the soundproof cover according to the embodiment in a closed state. [Figure 3] It is a plan view showing the soundproof cover according to the embodiment in an open state. [Figure 4] It is a cross-sectional view showing the soundproof cover according to the embodiment in a closed state. [Figure 5] It is a cross-sectional view showing the soundproof cover according to the embodiment in an open state. [Figure 6] It is a cross-sectional view showing the manufacturing process of the soundproof cover according to the embodiment. [Figure 7] It is a cross-sectional view showing the manufacturing process of the soundproof cover according to the embodiment. [Figure 8] It is a plan view showing the manufacturing process of the soundproof cover according to the embodiment. [Figure 9] It is a cross-sectional view showing the soundproof cover according to another embodiment in a closed state

Mode for Carrying Out the Invention

[0014] Next, the soundproof cover and the method for manufacturing the soundproof cover according to the present invention will be described below with reference to the accompanying drawings by giving preferred embodiments. The embodiments and drawings described below illustrate a part of the embodiments of the present invention, and are not used for the purpose of limiting to these configurations, and can be appropriately changed without departing from the gist of the present invention.

[0015] As shown in Fig. 1, the soundproof cover 10 according to the embodiment includes two (a plurality of) cover bodies 12 surrounding the sound source 50, a connecting portion (hinge 14 and abutting portion 16 described later) provided on the cover bodies 12 and connecting the cover bodies 12 to each other, and three-dimensional mesh bodies 18 and 20 (see Fig. 4) embedded in the connecting portion. The soundproof cover 10 includes, as the connecting portion, a hinge 14 that connects the two cover bodies 12 to be openable and closable, and an abutting portion 16 that abuts against each other when the two cover bodies 12 are closed. The soundproof cover 10 is in a closed state where the abutting portions 16 overlap each other by bending the hinge 14 and abutting the two cover bodies 12 against each other (see Figs. 2 and 4). At this time, the soundproof cover 10 is held in the closed state by inserting and fastening a connector 22 (see Fig. 4) such as a push clip into a through hole 16a formed through the abutting portion 16. Further, the soundproof cover 10 is in an open state by separating the two cover bodies 12 from each other with the hinge 14 as a fulcrum (see Figs. 3 and 5). The soundproof cover 10 is arranged to surround the sound source 50 and suppresses the sound emitted from the sound source 50 from leaking to the outside. Examples of the sound source 50 surrounded by the soundproof cover 10 include devices such as a compressor, a motor, and a pump, and it is particularly suitable for in-vehicle devices mounted on a vehicle.

[0016] As shown in Figure 4, the cover body 12 is formed in the shape of a container with one side open, and when the two cover bodies 12 are closed, a space is formed inside that matches the outer shape of the sound source 50. As shown in Figure 5, the cover body 12 has hinges 14 that protrude outward from its edge, and the two cover bodies 12 are connected by the hinges 14. The hinges 14 are plate-shaped and are so-called integral hinges that can be bent due to the toughness of the material that makes up the hinges 14. The hinges 14 also have a groove 14a in the center that extends in a direction perpendicular to the protruding direction of the hinges 14, and the thickness of the plate in the center of the hinges 14 is thinner than in other positions. The hinges 14 bend starting from the grooves 14a, and when the soundproof cover 10 is closed, the hinges 14 bend at the grooves 14a. As shown in Figure 3, a constriction 14b is formed in the center of the hinge 14, which is recessed inward in a plan view, and the width of the hinge 14 narrows at the position of the groove 14a.

[0017] As shown in Figure 5, the cover body 12 has a contact portion 16 that protrudes outward from its edge, and when the two cover bodies 12 are closed, the two contact portions 16 overlap and come into contact with each other. The contact portion 16 is plate-shaped and has a through hole 16a that penetrates in the direction of its plate thickness. When the two cover bodies 12 are closed and the contact portions 16 come into contact with each other, the through holes 16a of the two contact portions 16 align.

[0018] The cover body 12, including the hinge 14 and the contact portion 16, is entirely made of a soft foamed resin. Examples of foamed resins include polyurethane foam and olefin-based foam, and the cover body 12 is a molded product of foamed resin. By forming the cover body 12 from a soft foamed resin in this way, the sound-absorbing effect unique to the cell structure of the foamed resin is obtained, as well as the sound source 50 protection effect due to the flexibility of the soft foamed resin.

[0019] As shown in Figure 4, a first three-dimensional mesh body 18 (three-dimensional mesh body) is embedded in the hinge 14. Foamed resin constituting the hinge 14 is arranged within the mesh of the first three-dimensional mesh body 18. The first three-dimensional mesh body 18 is arranged in at least the area including the groove 14a in the protruding direction of the hinge 14, and preferably is arranged between the base of the hinge 14 that connects to the cover body 12 or a position close to the base. By doing so, the strength-enhancing effect of the hinge 14, which is created by the combined effect of the first three-dimensional mesh body 18 and the foamed resin arranged within the mesh of the first three-dimensional mesh body 18, can be increased. Furthermore, the first three-dimensional mesh body 18 may be arranged over the entire thickness or almost the entire thickness of the hinge 14, which also increases the strength-enhancing effect of the hinge 14, which is created by the combined effect of the first three-dimensional mesh body 18 and the foamed resin arranged within the mesh of the first three-dimensional mesh body 18. Furthermore, the first three-dimensional mesh body 18 may be arranged over the entire width of the hinge 14 or almost the entire width. By doing so, the effect of improving the strength of the hinge 14, which is generated by the combined effect of the first three-dimensional mesh body 18 and the foamed resin placed within the mesh of the first three-dimensional mesh body 18, can be increased.

[0020] As shown in Figure 4, a second three-dimensional mesh body 20 (three-dimensional mesh body) is embedded in the contact portion 16. Foamed resin constituting the contact portion 16 is arranged within the mesh of the second three-dimensional mesh body 20. The through-hole 16a of the contact portion 16 penetrates the embedded second three-dimensional mesh body 20. The second three-dimensional mesh body 20 is arranged to surround the through-hole 16a, thereby increasing the strength-enhancing effect of the contact portion 16, which is generated by the combined effect of the second three-dimensional mesh body 20 and the foamed resin arranged within its mesh. Furthermore, the second three-dimensional mesh body 20 may be arranged over the entire thickness of the contact portion 16 or almost the entire thickness direction, thereby increasing the strength-enhancing effect of the contact portion 16, which is generated by the combined effect of the second three-dimensional mesh body 20 and the foamed resin arranged within its mesh. Furthermore, the second three-dimensional mesh body 20 may be arranged over the entire width of the contact portion 16 or almost the entire width of the contact portion 16. By doing so, the effect of improving the strength of the contact portion 16, which is generated by the combined effect of the second three-dimensional mesh body 20 and the foamed resin placed within the mesh of the second three-dimensional mesh body 20, can be increased.

[0021] As the three-dimensional mesh bodies 18 and 20, foam, a three-dimensional network structure, or a porous material can be used. As foam, for example, polyurethane foam, polypropylene foam, or polyethylene foam can be used. As a three-dimensional network structure, a three-dimensional knitted fabric composed of a monofilament or multifilament connecting layer that links two layers of knitted fabric, front and back, can be used. Such a three-dimensional knitted fabric is also called a three-dimensional structured mesh, three-dimensional mesh, or three-dimensional structured mesh. A porous material is one that has many pores, such as a sponge. Among these, foam is preferred as the three-dimensional mesh bodies 18 and 20 from the viewpoint of compatibility with the foamed resin that constitutes the cover body 12 and resistance to the heat effects that occur when the cover body 12 is molded.

[0022] If the three-dimensional mesh bodies 18 and 20 are foams, an open-cell structure is used, that is, a structure in which cells are interconnected and cells open to the outer surface of the three-dimensional mesh bodies 18 and 20. As an open-cell foam, a defilmed foam is preferred, in which the cell membranes between cells have been removed. In a defilmed foam, only the three-dimensional mesh-like skeletal structure of the resin remains after the cell membranes have been removed. For example, the cell membranes may be removed by blowing them off with a blast of combustion gas, or by hydrolysis with alkali. Thus, if the three-dimensional mesh bodies 18 and 20 are defilmed foams, it is easy to arrange the foamed resin constituting the connecting parts 14 and 16 within the cells (mesh). Here, when the foamed resin is said to be arranged or impregnated within the mesh of the three-dimensional mesh bodies 18 and 20, it means that the foamed resin is arranged in the gaps between the skeletal structures that make up the mesh, and is different from the foamed resin penetrating the skeletal structure itself.

[0023] The foamed resin placed within the mesh of the three-dimensional mesh bodies 18 and 20 may be foamed, and in this case, its foaming ratio may be lower than that of the foamed resin outside the three-dimensional mesh bodies 18 and 20. The foamed resin may be placed in a portion of the surface area within the mesh of the three-dimensional mesh bodies 18 and 20, but placing it throughout the entire mesh of the three-dimensional mesh bodies 18 and 20 can increase the effect of improving the strength of the hinge 14 and the contact portion 16.

[0024] When using defilm removal foam, the cell count of the defilm removal foam is preferably in the range of 6 cells / 25 mm to 20 cells / 25 mm. When the cell count of the defilm removal foam is 20 cells / 25 mm or less, the cells of the defilm removal foam become relatively large, making it easier to arrange the foamed resin between the framework (mesh). Also, when the cell count of the defilm removal foam is 6 cells / 25 mm or more, the framework of the defilm removal foam becomes relatively thick, resulting in relatively high strength of the defilm removal foam. The cell count is a value measured according to JIS K6400-1.

[0025] The manufacturing method of the aforementioned soundproof cover 10 will be explained with reference to Figures 6 to 8. The soundproof cover 10 according to the embodiment is obtained by molding two cover bodies 12 in an open state using a mold 30 having a first mold 32 and a second mold 34. The first three-dimensional mesh body 18 is set in the hinge molding section 36 that molds the hinge 14 in the first mold 32 (see Figure 6). Here, the first three-dimensional mesh body 18 is a plate-like body having a recess 18a in the center that is recessed inward to match the constriction of the hinge 14 (see Figure 8), and the first three-dimensional mesh body 18 is positioned in the first mold 32 by fitting this recess 18a into the protrusion 36a that molds the constriction 14b in the first mold 32. In addition, the central part of the first three-dimensional mesh body 18 is held in a compressed state by being sandwiched between the protrusions 37 that mold the groove 14a of the hinge 14 when the mold is closed. The second three-dimensional mesh body 20 is set in the contact portion forming section 38 that forms the contact portion 16 in the first mold 32 (see Figure 6). Here, the second three-dimensional mesh body 20 has a hole portion 20a that penetrates in the plate thickness direction to match the through hole 16a (see Figure 8), and the second three-dimensional mesh body 20 is positioned in the first mold 32 by fitting this hole portion 20a into the projection 38a that forms the through hole 16a in the first mold 32.

[0026] As shown in Figure 7, the mold 30 is closed and foam resin material is injected into the cavity 30a formed between the first mold 32 and the second mold 34. At this time, the foam resin material enters the mesh of the first three-dimensional mesh body 18 installed in the hinge molding section 36 and the mesh of the second three-dimensional mesh body 20 installed in the contact section molding section 38. As the foam resin material flows through the mesh of the first three-dimensional mesh body 18 and the second three-dimensional mesh body 20, the foam resin material can be distributed throughout the entire hinge molding section 36 and the contact section molding section 38, thereby suppressing molding defects of the hinge 14 and the contact section 16. In this way, as the foam resin material foams and hardens to become foam resin, a cover body 12 made of soft foam resin is formed in the mold 30. Furthermore, the foamed resin material impregnated into the mesh of the first three-dimensional mesh body 18 foams up to form a hinge 14, and the foamed resin material impregnated into the mesh of the second three-dimensional mesh body 20 foams up to form a contact portion 16. Because the framework of the three-dimensional mesh bodies 18 and 20 is present, the degree of foaming of the foamed resin material that enters the mesh of the three-dimensional mesh bodies 18 and 20 is smaller than that of the outside of the three-dimensional mesh bodies 18 and 20, and the foaming ratio of the foamed resin generated inside the mesh is reduced. In this way, a soundproof cover 10 is obtained that comprises a cover body 12 made of soft foamed resin, a hinge 14 in which foamed resin is arranged within the mesh of the first three-dimensional mesh body 18 embedded therein, and a contact portion 16 in which foamed resin is arranged within the mesh of the second three-dimensional mesh body 20 embedded therein. Note that the foamed resin material may be injected into the first mold 32 before closing the mold 30, and then the first mold 32 and the second mold 34 may be closed.

[0027] The soundproof cover 10 comprises two cover bodies 12 made of soft foamed resin, hinges 14 and contact parts 16 provided on the cover bodies 12, a first three-dimensional mesh body 18 embedded in the hinge 14 with foamed resin arranged within the mesh, and a second three-dimensional mesh body 20 embedded in the contact part 16 with foamed resin arranged within the mesh. The foamed resin arranged within the mesh of the three-dimensional mesh bodies 18 and 20 has a lower foaming ratio and higher density compared to the foamed resin on the outside of the three-dimensional mesh bodies 18 and 20, thereby improving the hardness of the foamed resin arranged within the mesh compared to the foamed resin on the outside of the three-dimensional mesh bodies 18 and 20. Furthermore, the three-dimensional mesh bodies 18 and 20 act as reinforcing materials, improving the strength of the hinge 14 in which the first three-dimensional mesh body 18 is embedded and the contact part 16 in which the second three-dimensional mesh body 20 is embedded, compared to the cover body 12 in which the three-dimensional mesh bodies 18 and 20 are not embedded. Thus, the soundproof cover 10 is equipped with a hinge 14 and a contact portion 16 that have excellent strength. Furthermore, according to the manufacturing method described above, a soundproof cover 10 equipped with a hinge 14 and a contact portion 16 that have excellent strength can be easily obtained. It is preferable that the three-dimensional mesh bodies 18 and 20 are made of film-removing foam because they are inexpensive, the foamed resin is easily impregnated into the mesh, and they are less susceptible to the heat effects that occur when the cover body 12 is molded.

[0028] As mentioned above, the hinge 14 has the first three-dimensional mesh body 18 embedded in it, which, in addition to the improvement in hardness mentioned above, improves the breaking strength of the hinge 14 when it bends during opening and closing the cover body 12. Here, the foamed resin placed inside the first three-dimensional mesh body 18 has improved hardness, but because it is foamed, it retains flexibility. In the hinge 14 according to this embodiment, the first three-dimensional mesh body 18 acts as a reinforcing material, so even if a groove 14a is provided to determine the bending position in the hinge 14 and the wall is made thin, it becomes difficult to tear or break. In this way, the soundproof cover 10 can improve the durability of opening and closing the cover body 12 due to the high breaking strength of the hinge 14.

[0029] The contact portion 16 is the part that comes into contact with each other when the cover bodies 12 are closed, and has a through hole 16a that penetrates the embedded second three-dimensional mesh body 20. The contact portion 16 has increased hardness because the through hole 16a through which the connector 22 is inserted and removed is made of the second three-dimensional mesh body 20 in which foamed resin is arranged within the mesh, making it easier to insert and remove the connector 22 into the through hole 16a and improving the fastening strength when the connector 22 is fitted into the through hole 16a.

[0030] If the three-dimensional mesh bodies 18 and 20 are made of de-membrane urethane foam, setting the number of cells in the range of 6 cells / 25 mm to 20 cells / 25 mm provides a good balance between the ease of arranging the foamed resin within the mesh and the strength of the framework of the three-dimensional mesh bodies 18 and 20 themselves.

[0031] (Example test) Soundproof covers were fabricated with contact points containing embedded three-dimensional meshes with different cell counts, and the pull-out load of connectors from each contact point and the hardness of the contact points were evaluated. The foamed resin used was a soft polyurethane foam. The three-dimensional meshes used were MF8 (cell count: 8 cells / 25 mm), MF13 (cell count: 13 cells / 25 mm), and MF20 (cell count: 20 cells / 25 mm), which are defilm-removing foams manufactured by Inoac Corporation. The contact points had dimensions of 20 mm in the protruding direction from the cover body, a width of 25 mm, and a plate thickness of 5 mm, with a through hole of 5 mm in diameter. The three-dimensional meshes had dimensions of 18 mm in the protruding direction from the cover body, a width of 23 mm, and a plate thickness of 5 mm. For the connectors, brush clip model number 2488 manufactured by Nifco Corporation was used, and the pull-out load of the connector fitted into the through hole was measured using an autograph. In measuring the pull-out load, the connector pull-out speed was 10 mm / min. Asker C hardness was measured using a 10 mm thick flat plate according to JIS K 7312. The results are shown in Table 1. The comparative example soundproof cover is the same as in Test Examples 1-3, except that a three-dimensional mesh is not embedded in the contact area; the shape of the contact area and test conditions are the same.

[0032] [Table 1]

[0033] It was found that embedding a three-dimensional mesh in the contact area improved the pull-out load and hardness of the connection compared to a comparative example where the three-dimensional mesh was not embedded. Furthermore, it was found that using defilm foam with 8 cells / 25 mm to 20 cells / 25 mm as the three-dimensional mesh allowed for proper arrangement of the foamed resin within the mesh and suppressed molding defects in the contact area.

[0034] (Example of change) The present invention is not limited to the aforementioned matters, but may also be applied as follows, for example. Furthermore, the present invention is not limited to the embodiments and the following specific examples of modifications. (1) In the embodiment described above, there are two cover bodies, but the invention is not limited to this, and three or more cover bodies may be combined. (2) As in the embodiments described above, the entire cover body is not limited to being made of soft foamed resin; it is sufficient if at least a part of the cover body is made of foamed resin. Even in this case, it is preferable to make the connecting parts (hinge, contact parts) out of foamed resin.

[0035] (3) The hinge in the above-described embodiment does not have a through hole, but is not limited to this, and a through hole 15 similar to the through hole 16a provided in the contact portion 16 may be provided in the hinge 14, as in another embodiment shown in Figure 9. In this case, the through hole 15 should be provided in a symmetrical position on either side of the groove 14a at a location close to the base of the hinge 14 in which the three-dimensional mesh body 18 is embedded, and connected to the cover body 12. By doing so, the gap between the cover body 12s that tends to form on the base side of the hinge 14 when the cover body 12 is closed can be narrowed by the connector 22. [Explanation of Symbols]

[0036] 10 Soundproof cover, 12 Cover body, 14 Hinge (connecting part), 16 Contact part (connecting part), 18 First three-dimensional mesh body (three-dimensional mesh body), 20 Second three-dimensional mesh body (three-dimensional mesh body), 30 Molding mold

Claims

1. It is formed at least partially from soft foam resin, and consists of multiple cover bodies surrounding the sound source, The cover body is provided with a connecting portion that connects the cover bodies together, The connection portion comprises a three-dimensional mesh body embedded in it, A soundproof cover in which the foamed resin is arranged within the mesh of the three-dimensional mesh body.

2. The soundproof cover according to claim 1, wherein the three-dimensional mesh body is a de-membrane urethane foam.

3. The soundproof cover according to claim 1, wherein the connecting portion is a hinge that connects the cover bodies in an openable and closable manner.

4. The soundproof cover according to claim 1, wherein the connecting portion is a contact portion that abuts against each other when the cover bodies are closed, and has a through hole that penetrates the embedded three-dimensional mesh body.

5. The soundproof cover according to claim 2, wherein the number of cells in the defilmed urethane foam is in the range of 6 cells / 25 mm to 20 cells / 25 mm.

6. A method for manufacturing a soundproof cover comprising a plurality of cover bodies surrounding a sound source, and connecting parts provided on the cover bodies for connecting the cover bodies to each other, A three-dimensional mesh body is placed in the part of the mold used to form the cover body and the connecting part, A method for manufacturing a soundproof cover, comprising injecting foamed resin raw material into the mold to form the cover body, which is at least partly made of soft foamed resin, and impregnating the mesh of the three-dimensional mesh body with the foamed resin raw material to form the connecting portion which is made of foamed resin.

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