JP2005238768A - Foaming member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inhibit the poor shaping of a foam element foamed between a substrate and a facing material. <P>SOLUTION: The thickness S (S1, S2, S3, S4) of a facing material 14 is varied with the thickness H (H1, H2, H3, H4) of a foaming member 30. By this, the thickness of a foaming space 18 defined between a substrate 12 and the facing material 14 is fixed approximately, and the thickness F (F1, F2, F3, F4) of a foam element 16 foamed in this foaming space 18 is also fixed approximately at any part. In addition, the above facing material 14 molded from the reaction injection molding technique is implemented suitably. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a foam-molded member, and more specifically, relates to a foam-molded member comprising a base material and a skin material, and a foam interposed between the two members, the thickness of which varies depending on each part. Is.

For example, as illustrated in FIG. 7, a synthetic resin base material 12 preformed in a required shape, and a synthetic resin skin material 14 preformed in the required shape and disposed outside the base material 12. The foam molded member 10 having a three-layer structure composed of a foam 16 interposed by foam molding between the base material 12 and the skin material 14 is implemented as an instrument panel, a floor console, or the like that is a vehicle interior member. It is offered to. The base material 12 mentioned above is a synthetic resin molded member molded from a resin raw material such as polyethylene (PE) or polypropylene (PP) based on an injection molding technique or the like. Further, the skin material 14 has been suitably implemented conventionally (a) one formed from a resin sheet material based on vacuum forming technology, (b) one formed from resin powder based on powder slush molding technology, and the like. ing. And the foam 16 is shape | molded based on foam molding technology from foaming raw materials, such as a polyurethane, and has appropriate elasticity. Such a foam-molded member having a three-layer structure is disclosed in Patent Document 1, for example.
JP 2000-246742 A

  The foamed molded member 10 described above has a wide variety of shapes, sizes, designs, and the like depending on the purpose of use, and is often designed to have a complicated external design shape combining concave and convex portions and curved surface portions. Here, the skin material 14 exposed on the outer surface of the foam molded member 10 needs to be molded in the same shape as the outer surface design shape, but is thin and thin with a thickness S of about 1 mm, and thus is flexible. Even a fairly complicated shape can be molded with a skin mold and can be removed from the skin mold. However, the above-described base material 12 has a limitation in molding technology (mainly whether or not it can be removed from the base material mold), and therefore cannot be formed into a complicated shape approximate to the above-described skin material 14. In other words, the mold must be formed in a shape that allows for removal from the base mold. For this reason, in the foam molded member 10 illustrated in FIG. 7, the shape of the skin material 14 and the base material 12 is large at the bent portion 20, the central portion 22, the boss forming portion 24, the opening forming portion 26, etc. on the left side in the drawing. Accordingly, the thicknesses H (H1, H2, H3, H4) of these portions 20, 22, 24, 26 are greatly different.

  Further, the skin material 14 formed based on the above-described vacuum forming technique or powder slush forming technique can be formed only to a substantially uniform thickness S as a whole due to the characteristics of the forming technique. For this reason, the foaming space 18 defined between the front surface 12A of the base material 12 and the back surface 14B of the skin material 14 includes the bent portion 20, the central portion 22, and the boss forming portion described above as illustrated in FIG. 24 and the opening forming portion 26 have greatly different thicknesses D (D1, D2, D3, D4), and corner portions are defined when the shape change is large. The thickness F (F1, F2, F3, F4) of the foam 16 molded inside is also different for each part 20, 22, 24, 26 (FIG. 7). In other words, when the thickness H of the conventional foamed molded member 10 is different depending on each part, the thickness F of the foam 16 is changed to cope with it.

  However, when the thickness D (D1, D2, D3, D4) of the foaming space 18 is different in each of the aforementioned parts (the bent part 20, the boss forming part 24, the opening forming part 26), When the foaming raw material injected into is expanded and expanded, air tends to remain in the corners of these portions 20, 22, 24, and 26. Further, in the final curing stage of the foam 16, the shrinkage rate increases as the thickness F increases, and this tendency is particularly remarkable in the bent portion 20, the boss forming portion 24, the opening forming portion 26, and the like. Appears. For this reason, the bent portion 20, the boss forming portion 24, the opening forming portion 26, and the like described above, as illustrated in FIG. 9 and FIG. 10, are inside the foam 16 and / or the foam 16 and the skin material. Cavity B due to the presence of residual air is formed between them and a recess is formed at a corresponding portion of the skin material 14 forming the external design surface of the foam molded member 10, thereby causing a product defect. It was inherent.

  Therefore, in the present invention, by changing the thickness of the skin material and / or the thickness of the base material and making the thickness of the foam interposed between the skin material and the base material substantially constant at any part, An object of the present invention is to provide a foam molded member configured to suitably prevent molding defects of the foam.

In order to solve the above-mentioned problems and achieve the intended purpose, the present invention provides:
In a foam molded member comprising a base material and a skin material, and a foam interposed between both members, the thickness of which varies depending on each part,
The thickness of the skin material and / or the thickness of the base material is changed according to the thickness of the foam molded member,
The thickness of the foam interposed between the base material and the skin material is configured to be substantially constant at any part thereof.

In order to solve the above-mentioned problem and achieve the intended purpose, another invention is as follows.
In the foam-molded member comprising a base material and a skin material that have been preformed respectively, and a foam that is foam-molded between the base material and the skin material, the thickness of which varies depending on each part,
The thickness of the skin material and / or the thickness of the base material is changed according to the thickness of the foam molded member,
By making the thickness of the foaming space defined between the base material and the skin material substantially constant, the thickness of the foam foam-molded in the foaming space can be made substantially constant at any part thereof. It is characterized by comprising.

  According to the foam molded member according to the present invention, by changing the thickness of the skin material and / or the thickness of the base material according to the thickness of the foam molded member, the distance between the back surface of the skin material and the surface of the base material is changed. Any of these parts can be made substantially constant. Therefore, there is an advantage that the thickness of the foam interposed between the skin material and the base material can be made substantially constant at any part thereof.

  According to the foam-molded member according to another invention, the thickness of the skin material and / or the thickness of the base material is changed according to the thickness of the foam-molded member, and the distance between the back surface of the skin material and the surface of the base material, By making the thickness of the foaming space defined between them substantially constant, there is an advantage that the thickness of the foam molded in the foam space can be made substantially constant at any part thereof. . Therefore, when the foam is foam-molded in the foam space, air can be prevented from remaining in the foam space, and the shrinkage rate of the foam is substantially constant as a whole. Or, there is a beneficial effect such that it is possible to suitably avoid occurrence of defective foaming due to the formation of a cavity between the foam and the skin material.

  Next, preferred embodiments of the foam molded member according to the present invention will be described below with reference to the accompanying drawings. In the examples described later, in order to clarify the difference between the foam molded member of the present example and the conventional foam molded member 10 illustrated in FIG. 7, a foam molded member having the same shape as the foam molded member 10 is used. Illustrate. Therefore, the same members / parts as those already shown in FIGS. 7 to 10 will be described with the same reference numerals.

(First embodiment)
FIG. 1 is a schematic cross-sectional view showing the structure of a foam molded member according to the first embodiment. The foam molded member 30 of the first embodiment is basically the same as the conventional foam molded member 10 illustrated in FIG. 7, the synthetic resin base material 12 preformed in a required shape, and a preliminary shape in the required shape. A three-layer structure comprising a synthetic resin skin material 14 that is molded and disposed outside the base material 12, and a foam 16 interposed between the base material 12 and the skin material 14 by foam molding. It has a structure. The foam molded member 30 of the first embodiment has the same shape as that used for the conventional foam molded member 10 in the base material 12, and the thickness S of the skin material 14 is set to the foam molded member 30 concerned. By changing the thickness according to the thickness H, the distance between the back surface 14B of the skin material 14 and the surface 12A of the base material 12, that is, the thickness of the foaming space 18 defined between the skin material 14 and the base material 12. It is characterized in that D is substantially constant and the thickness F of the foam 16 formed by foaming in the foaming space 18 is substantially constant at any part thereof.

  The base material 12 is a synthetic resin molded member formed by injection molding using, for example, an injection mold (not shown), an olefin-based synthetic resin such as polyethylene (PE) or polypropylene (PP). The base material 12 is provided with a bent portion 32 corresponding to the bent portion 20 described above, and a boss 36 protruding from the back surface of the concave portion 34 provided corresponding to the boss forming portion 24 described above. An opening 40 is formed in a recess 38 provided corresponding to the part 26. The base material 12 is generally configured with the bent portion 32, the boss portion 36, the recessed portion 38, and the like set to a shape / angle, etc., that is allowed to be removed after molding by an injection mold (not shown). The shape is similar to the outer surface design shape of the foam molded member 30. In addition, the thickness K of the base material 12 is set to about 2 mm which is substantially uniform in any part including the bent part 32, the recessed part 34, the recessed part 38, and the like.

  The skin material 14 is a urethane molding material molded based on a reaction injection molding technique. In this reaction injection molding technique, as is well known, a foaming raw material polyol and isocyanate are injected into a cavity of a required shape defined in a skin mold while stirring, and these are reacted in the cavity. This is a method of forming a urethane molded material having the same outer shape as the cavity by advancing the foaming reaction. Therefore, for example, a sheet-like member having a different thickness for each part, a member having a complicated outer surface shape having a concavo-convex portion and / or a curved surface portion, etc. can be removed from the forming die in the same manner as a general injection molding technique. If it is a simple shape, it has a feature that it can form a wide variety of shapes.

  As illustrated in FIG. 1, the skin material 14 of the first embodiment that is molded based on such a reaction injection molding technique has its thickness changed for each part by taking advantage of the characteristics of this molding technique. The shape of the front surface 14 </ b> A is the same shape as the external design shape required for the foam molded member 30, and the shape of the back surface 14 </ b> B is a shape that approximates the shape of the surface 12 </ b> A of the substrate 12. That is, the thickness S of the skin material 14 is set to about 1 mm at the corresponding portion of the portion where the thickness H of the foamed molded member 30 is set to the minimum, and the bent portion 20, the central portion 22, and the boss formation are thicker than this. In the part 24, the opening forming part 26, and the like, the thicknesses are set to S1, S2, S3, and S4, which are larger than this.

  And by making the shape of the back surface 14B of the skin material 14 approximate to the shape of the surface 12A of the base material 12, the distance between the surface 12A of the base material 12 and the back surface 14B of the skin material 14, that is, of these members As shown in FIG. 4, the thickness D of the foaming space 18 defined between them is substantially the same at any part (D1 = D2 = D3 = D4). That is, when the foam mold is closed with the base material 12 and the skin material 14 set in a foam mold (not shown), the bent portion 20, the central portion 22, the boss forming portion 24, the opening forming portion 26, etc. The thickness D of the foaming space 18 defined between the front surface 12A of the base material 12 and the back surface 14B of the skin material 14 is set to be substantially constant in all the parts including the base material 12. The thickness D of the foam space 18 varies depending on the size and shape of the foam molded member 30, the intended use, and the like, but is generally set within a range of about 5 to 7 mm. Here, “substantially constant” as defined in the present application includes “constant” in which the thickness D is the same in all the parts.

  Therefore, since the foam 16 is formed in the foaming space 18 described above, when the foaming material injected into the foaming space 18 expands and expands, the thickness D in the foaming space 18 changes rapidly. In addition, since the corners are not defined in the above-described portions 20, 22, 24, 26, etc., as illustrated in FIG. 2 and FIG. It will not remain. Further, since the thickness D of the foaming space 18 is substantially constant, when the foam 16 to be molded is finally cured, the shrinkage rate is substantially constant at any part. Therefore, the cavity B caused by the residual residual air illustrated in FIGS. 9 and 10 may be formed at all inside the molded foam 16 and / or between the foam 16 and the skin material 14. Therefore, no depressions or the like are formed at appropriate portions of the skin material 14 constituting the external design surface of the foam molded member 30.

  Thus, in the foam molded member 30 of the first embodiment, the thickness S of the skin material 14 is set to the thickness of the foam molded member 30 on the assumption that the skin material 14 is molded based on the reaction injection molding technique. The distance between the back surface 14B of the skin material 14 and the front surface 12A of the base material 12 is changed according to H (where the thickness H of the foamed molded member 30 is large, the thickness S of the skin material 14 is also set large). That is, the thickness D of the foaming space 18 defined between them is made to be substantially constant at any part thereof. Therefore, the thickness F of the foam 16 that is foam-molded in the foam space 18 is substantially constant at any part thereof, and air can be prevented from remaining in the foam space 18 and the shrinkage rate of the foam 16 can be reduced. Since it becomes substantially constant as a whole, it is possible to suitably avoid occurrence of defective foam molding due to the formation of the cavity B inside the foam 16 and / or between the foam 16 and the skin material 14.

(Second embodiment)
FIG. 5 is a schematic cross-sectional view showing the structure of a foam molded member according to the second embodiment. In the foam molded member 50 of the second embodiment, both the thickness K of the base material 12 and the thickness S of the skin material 14 change according to the thickness H (H1, H2, H3, H4) of the foam molded member 30 concerned. By doing so, the distance between the back surface 14B of the skin material 14 and the front surface 12A of the base material 12, that is, the thickness D of the foaming space 18 defined between both members is made substantially constant at any part. It is composed. That is, on the premise that demolding at the time of injection molding is permitted, the base material 12 has a thickness K2 as a convex curved surface shape that approximates the surface shape of the portion corresponding to the central portion 22 described above to the shape of the external design surface, for example. Is set large, and the surface shape of the portion corresponding to the boss forming portion 24 described above is flat, and the thickness K3 is set large. In addition, the thickness K1 of the site | part corresponding to the bending site | part 20 mentioned above and the thickness K4 of the site | part corresponding to the opening formation site | part 26 are made the same with the base material 12 of 1st Example. On the other hand, on the premise that the skin material 14 is molded based on the reaction injection molding technique described above, the thickness S2 of the part corresponding to the central part 22 and the thickness S3 of the part corresponding to the boss forming part 24 are usually set. Thickness (about 1 mm). The thickness S1 of the portion corresponding to the bent portion 20 and the thickness S4 of the portion corresponding to the opening forming portion 26 are the same as those of the skin material 14 implemented in the first embodiment.

  When the foaming mold is closed with the base material 12 and the skin material 14 molded as described above set in a foaming mold (not shown), as shown in FIG. 22, the thickness D (D1, D2) of the foaming space 18 defined between the front surface 12A of the base material 12 and the back surface 14B of the skin material 14 in all the parts including the boss forming part 24, the opening forming part 26, and the like. , D3, D4) are substantially constant. Therefore, as in the first embodiment described above, when the foam 16 is foam-molded in the foam space 18, no air remains in the foam space 18 and the shrinkage rate of the foam 16 is totally reduced. Therefore, the cavity B is not formed inside the foam 16 and / or between the foam 16 and the skin material 14.

  Thus, in the foam molded member 50 of the second embodiment, the thickness S of the skin material 14 and the thickness K of the base material 12 are based on the premise that the skin material 14 is molded based on the reaction injection molding technique. By changing both of these according to the thickness H of the foam molded member 30, the thickness D of the foam space 18 defined between the back surface 14B of the skin material 14 and the surface 12A of the base material 12 is made substantially constant. Thus, the thickness F of the foam 18 formed by foaming in the foaming space 18 is made substantially constant at any part thereof. Accordingly, when foaming the foam 16 in the foaming space 18, air can be prevented from remaining in the foaming space 18 and the shrinkage rate of the foam 16 is substantially constant as a whole. It is possible to preferably avoid occurrence of defective foam molding due to the formation of the cavity B inside the body 16 and / or between the foam 16 and the skin material 14.

(Example of change)
In addition, regarding the base material 12 described above, if it is possible to freely set the shape of the surface 12A on the premise that demolding is allowed at the time of injection molding, only the thickness K of the base material 12 is set. By changing the foam molding member 30 according to the thickness H, the distance between the back surface 14B of the skin material 14 and the surface 12A of the base material 12, that is, the thickness D of the foam space 18 is substantially reduced at any part. It can be configured to be constant. In this case, the skin material 14 can be set to have a substantially uniform thickness S in any part. Therefore, the skin material 14 is not limited to the one formed on the basis of the reaction injection molding technique described above, but the conventional vacuum molding technique. It is possible to suitably implement those molded based on the above, those molded based on the powder slush molding technique, and those molded based on the spray molding technique.

  In the first embodiment and the second embodiment described above, the foam molded members 30 and 50 obtained by foam molding the foam 16 between the base material 12 and the skin material 14 that have each been preformed are exemplified. However, the foam molded member targeted by the present application is not limited to that obtained by such a molding method. For example, (a) a foam molded member obtained by pasting a separately prepared foam 16 on the surface 12A of the preformed base material 12 and setting the skin material 14 with the foam 16 set in a skin mold. (B) A foam molded member obtained by pasting a separately prepared foam 16 on the surface 12A of the preformed base material 12, and further pasting a separately formed skin material 14 on the surface of the foam 16, etc. Is also included. In the case of such a paste-type foam molded member, if the skin material 14 is molded based on the reaction injection molding technique described above, the thickness S of the skin material 14 depends on the thickness H of the foam molded member. Therefore, a ready-made foam sheet material standardized to a certain thickness can be implemented as the foam 16. That is, since the thickness F of the foam 16 interposed between the base material 12 and the skin material 14 can be made substantially constant at any part, production rationalization, cost reduction, etc. of the foam molded member can be expected.

  Furthermore, the foam molded member 30 targeted by the present application is not limited to the shape illustrated in FIG. 1 and FIG. In each of the above-described embodiments, the foam molded members 30 and 50 having a so-called three-layer structure in which the foam 16 and the skin material 14 are disposed on the entire surface 12A of the base material 12 are illustrated. The foamed molded member includes a so-called partial three-layer structure in which the foam 16 and the skin material 14 are disposed on a part of the surface 12A of the base 12.

  The foam molded member according to the present invention is a foam molded member comprising a base material and a skin material, and a foam interposed between the two members, the thickness of which varies depending on each part. It can be suitably implemented as a vehicle interior member such as a maintenance panel or a floor console.

It is the schematic sectional drawing which showed the structure of the foaming molding member which concerns on 1st Example. It is the elements on larger scale of the foaming molding member shown in FIG. 1, Comprising: The bending site | part is shown. It is the elements on larger scale of the foaming molding member shown in Drawing 1, Comprising: The opening formation part and the boss formation part are shown. In the foam molding member of 1st Example, it is explanatory sectional drawing which showed the state before foam-molding a foam. It is the schematic sectional drawing which showed the structure of the foaming molding member which concerns on 2nd Example. In the foam molding member of 2nd Example, it is explanatory sectional drawing which showed the state before foam-molding a foam. It is the schematic sectional drawing which showed the structure of the conventional foaming molding member. It is explanatory sectional drawing which showed the state before foam-molding a foam in the conventional foam-molding member. FIG. 8 is an explanatory cross-sectional view showing that a void due to air remaining in the foaming space is formed at a bent portion of the foam molded member illustrated in FIG. 7, resulting in a foam molding failure of the foam. FIG. 8 is an explanatory cross-sectional view showing that a void formed by air remaining in the foaming space is formed in the opening forming part and the boss forming part of the foam molded member shown in FIG.

Explanation of symbols

12 Base material 14 Skin material 16 Foam 18 Foam space 30,50 Foam molded member D Thickness (of foam space)
H Thickness (for foam molded parts)
K thickness (base material)
S Thickness (of the skin material)
F Thickness (of foam)

Claims (5)

The base material (12) and the skin material (14), and a foam (16) interposed between both members, the thickness (H) is a foam molded member (30, 50)
The thickness (S) of the skin material (14) and / or the thickness (K) of the base material (12) is changed according to the thickness (H) of the foamed molded member (30, 50),
The foam molding characterized in that the thickness (F) of the foam (16) interposed between the base material (12) and the skin material (14) is substantially constant at any part thereof. Element. Each of the base material (12) and the skin material (14) subjected to preforming, and the foam (16) foam-molded between the base material (12) and the skin material (14), the thickness ( In the foamed molded member (30, 50) in which H) is different depending on each part,
The thickness (S) of the skin material (14) and / or the thickness (K) of the base material (12) is changed according to the thickness (H) of the foamed molded member (30, 50),
By making the thickness (D) of the foaming space (18) defined between the base material (12) and the skin material (14) substantially constant, the foaming molding is performed in the foaming space (18). A foam molded member, characterized in that the thickness (F) of the foam (16) is substantially constant at any part thereof.   The foam molded member according to claim 1 or 2, wherein when only the thickness (S) of the skin material (14) is changed, a skin material (14) molded based on a reaction injection molding technique is implemented.   When changing only the thickness (K) of the base material (12), the skin material (14) molded based on any one of the vacuum molding technology, powder slush molding technology, spray molding technology or reaction injection molding technology is implemented. The foam-molded member according to claim 1 or 2. When changing both the thickness (S) of the skin material (14) and the thickness (K) of the base material (12), the skin material (14) molded based on a reaction injection molding technique is implemented. Item 3. The foam molded member according to Item 1 or 2.

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