Manufacturing method for foam molded article, backing material and foam molded article

Abstract

To provide a method for producing a foam molded article, which can produce a foam molded article by setting a backing material in the correct position on the back surface of a pad, and to provide a backing material and a foam molded article. [Solution] The method for manufacturing a foam molded product includes the steps of preparing a backing material 30 for reinforcing a pad 20, the backing material having a separation-intended portion D (perforations 34) for later separation of a portion of the backing material, a setting step of setting the backing material 30 in an upper mold 41, a step of injecting a foamable raw material into a lower mold 46, and a foam molding step of filling the foamable raw material into the cavity of the closed mold, foaming the foamable raw material to form a pad 20, and integrating the backing material 30 with the pad to obtain a foam molded product. At a timing later than the setting step or the foam molding step, a portion of the backing material 30 is separated along the separation-intended portion D.

Description

[Technical Field]

[0001] The present application relates to a foam molded article having a pad and a backing material integrally fixed to the back side of the pad, and to a method for producing the foam molded article by filling a foamable raw material into a mold and foaming it.The application also relates to a foam molded article and a backing material used in the production method thereof. [Background technology]

[0002] Patent Document 1 discloses a vehicle seat 1 in which an airbag module 4 is incorporated into the side of the seat back 2 (backrest). According to Figures 1 and 3 and paragraph 0014 of the document, the seat back is formed by integrally molding a seat pad 3 and a seat cover 7, and the seat pad 3 is provided with a backing material 31 on the side opposite the seat cover 7. The 11th sentence of paragraph 0014 of the document explains, "Note that although the seat pad 3 is provided with a backing material 31, there is a portion between the airbag module 4 and the burst line 75 where the backing material 31 is not provided." This is because, when the airbag module 4 is activated, the bag body 41 applies pressure to the portion where the backing material 31 is not provided, thereby enabling the bag body 41 to break through the burst line 75.

[0003] In general, when foam molding a seat pad (foam molded article) with a backing material, the backing material is set in advance on one side of the mold (usually the upper mold), and the pad main body is foam molded after the upper and lower molds are closed. However, if there is a portion (of the pad main body to be obtained) where the backing material is not provided (i.e., a portion where the backing material is partially interrupted and discontinuous), the separated portions of the backing material will move when setting the backing material in the mold, making it difficult to determine its position. As a result, it becomes difficult to set the backing material in the correct position in the mold (upper mold). If foam molding is performed without setting the entire backing material in the correct position in the mold, the seat pad obtained will have at least a portion of the backing material displaced from the correct position on the back surface of the pad (i.e., a defective or non-compliant foam molded article), which is undesirable. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2014-189239 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a method for producing a foam molded article, which allows a backing material to be set in the correct position on the back surface of a pad to produce a foam molded article, and to provide a backing material to be used in the production method, and a foam molded article obtained by the production method. [Means for solving the problem]

[0006] The invention of claim 1 is a method for producing a foam molded product in which a pad made of a foam material and a backing material fixed to the back side of the pad are integrated, using a molding die having first and second dies that can form a cavity when the die is closed, a preparation step of preparing a backing material for reinforcing the pad, the backing material having a separation portion formed thereon for separating a portion of the backing material later; a setting step of setting the back surface material in a first mold of the molding die; an injection step of injecting a foamable raw material into a second mold of the molding die; a foam molding step of closing the first mold against the second mold, filling a foamable raw material into a cavity of the molding mold, foaming the foamable raw material to form a pad, and integrating the backing material with the pad to obtain a foam molded article; The method for producing a foamed molded article is characterized by comprising the steps of:

[0007] According to the manufacturing method of the present invention, the lining material used has a separation-intended portion for separating (or dividing) a portion thereof later, and when the lining material is set in the first mold of the molding die, the separation-intended portion is in an unseparated, connected state. Therefore, compared with conventional lining materials in which a portion of the lining material is already separated when set, the lining material is easier to handle in the setting step, and the entire lining material can be set correctly in the desired position on the molding die. On the other hand, since the portion of the lining material (the separation-intended portion) can be separated (or divided) later in a step or at a timing subsequent to the setting step, a foam molded article can be obtained in which a portion (desired portion) of the lining material is separated.

[0008] The invention of claim 2 is characterized in that in the method for producing a foam molded article of claim 1, the separation-intended portion of the back surface material is at least partially constituted by perforations.

[0009] According to the invention of claim 2, in addition to the effects of the invention of claim 1, the following effect can be obtained: By forming at least a part of the separation portion as a perforation, the separation portion can be easily configured.

[0010] The invention of claim 3 is characterized in that, in the method for manufacturing a foam molded body described in claim 1, a portion of the back surface material is separated along the intended separation portion at a timing later than the setting process or the foam molding process.

[0011] According to the invention of claim 3, in addition to the effects of the invention of claim 1, the following effect can be obtained. That is, at the stage of setting the backing material in the mold, a part of the backing material (the part to be separated) is not separated (or divided), so the workability in the setting step is improved compared to conventional methods. On the other hand, by separating a part of the backing material along the part to be separated at a timing after the setting step or the foam molding step, it is possible to finally obtain a foam molded article in which the desired part of the backing material is separated.

[0012] The invention of claim 4 is characterized in that, in the method for manufacturing a foamed molded body described in claim 1, the back surface material prepared in the preparation step has a folded portion that will be positioned in a position that is not visible to an operator when the back surface material is set in the first mold, and the intended separation portion is formed in the folded portion.

[0013] According to the invention of claim 4, in addition to the effect of the invention of claim 1, the following effect can be obtained: When the lining material is set in the first mold, the folded portion of the lining material is positioned in a position that is not visible to the worker, but at the setting stage, the portion of the lining material to be separated remains connected (not yet separated), making it easy to set the lining material (especially the folded portion) in the first mold.

[0014] The invention of claim 5 is a backing material used in the method for producing the foam molded article according to any one of claims 1 to 4, A backing material characterized in that it has a separation-intended portion for separating a part of the backing material later, and the separation-intended portion can maintain an unseparated connected state at least until the backing material is set in a molding die.

[0015] According to the invention of claim 5, by using such a backing material, it becomes possible to smoothly carry out the methods for producing foamed molded articles according to claims 1 to 4.

[0016] The invention of claim 6 is as follows: A pad made of a foam material; a backing material integrally fixed to the back side of the pad to reinforce the pad; In a foamed molded article comprising: The foam molded article is characterized in that the back surface material has a separation-intended portion for later separation of a portion of the back surface material, and the separation-intended portion remains in an unseparated, connected state when foam molding of the foam molded article is completed.

[0017] According to the invention of claim 6, the foam molded article comprises a back surface material having a separation portion, which remains connected and unseparated when foam molding of the foam molded article is completed. Therefore, the separation portion can be separated (or cut) as needed to produce a desired foam molded article.

[0018] The invention of claim 7 is characterized in that, in the foam molded body described in claim 6, the pad has a separation portion as a recess or void at a position corresponding to the intended separation portion of the backing material.

[0019] According to the invention of claim 7, in addition to the effect of the invention of claim 6, the following effect can be obtained: Since the pad is provided with a separation portion as a recess or void at a position corresponding to the separation portion of the backing material, even when separating (or dividing) the separation portion of the backing material, the pad does not get in the way of the separation operation, and therefore the separation portion can be easily separated. [Effects of the Invention]

[0020] According to the method for producing a foam molded article of the present invention and the backing material used in the production method, the foam molded article can be produced by setting the backing material in the correct position on the back surface of the pad. According to the foam molded article of the present invention, the intended separation portion, which remains connected and unseparated at the time of completion of foam molding, can be separated as necessary to obtain a desired foam molded article. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 2 is a perspective view of a seat pad as a foam molded body, viewed from the back side. [Figure 2] FIG. 2 is a perspective view of a backing material for a foam molded article as viewed from the back side. [Figure 3] FIG. 2 is a perspective view of a backing material for a foam molded article, viewed from the front side. [Figure 4] FIG. 2 is a perspective view of a mold for a foam molded article (in an open state). [Figure 5]5A is a partially enlarged view of the circle V portion in FIG. 2, and FIG. 5B is a partially enlarged view of a comparative example, equivalent to FIG. 5A. [Figure 6] FIG. 6 is a partially enlarged view equivalent to FIG. 5(A) showing another example of the back surface material. DETAILED DESCRIPTION OF THE INVENTION

[0022] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described with reference to the drawings, in which the present invention is embodied in a seat pad for a front seat back (backrest portion) of a passenger vehicle.

[0023] [Seat pad as foam molding] FIG. 1 shows the entire seat pad 10, which is one component of the seat back of a front seat (in this example, the passenger seat). The seat pad 10 includes a pad 20 made of a foam material and a backing material 30 integrally fixed to the back side of the pad. The pad 20 is made of a foam material such as urethane foam, and is a component that primarily ensures cushioning. The backing material 30 is a cloth-like component made of a non-foam material such as nonwoven fabric, and when integrated with the pad 20, it functions to reinforce the foam molded body (seat pad) and to prevent noise from rubbing against the metal seat frame. The backing material 30 will be described in detail later.

[0024] As shown in FIG. 1, the pad 20 has left and right volume portions (21L, 21R) extending generally vertically (heightwise) on both left and right sides. The right volume portion 21R has a folded portion 22 located near its upper end and extending downward, and a right end portion 23 located to the right of the folded portion 22. A separation portion 24, which serves as a recess or void extending vertically (heightwise), is formed between the folded portion 22 and the right end portion 23 of the right volume portion 21R. This separation portion 24 is provided to ensure the mobility and deformability of the foam molded body, making it easier to remove the foam molded body from the molding die 40 (see FIG. 4) after foam molding is completed. In the completed seat pad 10, no backing material is placed (or no backing material is required) in the position corresponding to the separation portion 24.

[0025] 1, a through-hole 25 is provided near the upper end of the right volume portion 21R of the pad, opening on the right side. This through-hole 25 provides a storage space for various operating devices (for example, switches for adjusting the reclining state of the rear seats by the driver sitting in the driver's seat).

[0026] [Backing material for foam molding] 2, 3 and 5(A) show the backing material 30 used in this embodiment. As shown in these drawings, the backing material 30 has a three-dimensional shape corresponding to the shape (concave and convex shape) of the back surface of the pad 20. Specifically, the backing material 30 has left and right volume portion-corresponding lining portions 31L, 31R corresponding to the left and right volume portions 21L, 21R of the pad, A folded portion 32 of the backing material corresponding to the folded portion 22 of the pad, and a through-hole-corresponding lining portion 33 corresponding to the through-hole 25 of the right volume portion 21R of the pad; The folded portion 32 of the back surface material is disposed at a position that is not visible to an operator when the back surface material 30 is set in the forming mold 40 (FIG. 4).

[0027] Such a three-dimensional or cubic shaped backing material 30 can be made by known press molding or sewing. When press molding is used, a fabric sheet made of nonwoven fabric or felt is heated and softened, and then press molded using a shaping die, thereby obtaining a three-dimensional backing material that matches the shape of the back surface of the pad (see, for example, JP 2015-16036 A). When sewing is used, a three-dimensional backing material that matches the shape of the back surface of the pad can be obtained by making cuts in appropriate places in a fabric sheet made of nonwoven fabric or felt and sewing the appropriate places.

[0028] In the back surface material 30 of this embodiment, a separation portion D is formed in the folded portion 32 (see FIGS. 2 and 5(A)). The separation portion D shown in FIGS. 2 and 5(A) is entirely composed of a perforation 34. Specifically, the perforation 34 starts from the end edge 32a of the folded portion (illustrated as the edge 32a of the tip portion of the folded portion hanging downward in FIG. 2 etc.) and extends from there in an almost straight line toward the base of the folded portion 32 (the base end portion opposite the tip portion). The length (extension length) of the perforation 34 is not particularly limited and is set appropriately depending on the length of the folded portion 32 (for example, 1 to 4 cm).

[0029] Regarding the perforations 34 as the intended separation portions, the perforations 34 (i.e., the separation of a portion of the back surface material 30) can be achieved by separating the back surface material 30 along the perforations afterward. However, in this embodiment, the perforations 34 as the intended separation portions are kept in an unseparated (undivided) connected state at least until the back surface material 30 is set in the molding die 40 described below.

[0030] [Mold for foam molding] As shown in Fig. 4, the molding die 40 used in this embodiment has an upper die 41 as a first die and a lower die 46 as a second die. The upper die 41 is rotatably provided with respect to the lower die 46 by a hinge mechanism (not shown), and the molding die 40 can be in either an open state (Fig. 4) in which the upper die 41 is separated from the lower die 46, or a closed state (not shown) in which the upper die 41 is close to the lower die 46.

[0031] The lower mold 46 has an upper surface 47 that can face the upper mold 41. The lower mold 46 is formed with a molding recess 48 that opens to the upper surface 47 side of the lower mold.

[0032] The upper mold 41 is composed of an upper mold body 42 having a lower surface 42a that can face the lower mold 46, and a core mold portion 43 provided on the lower surface side of the upper mold body. The core mold portion 43 is provided so as to hang from the lower surface side of the upper mold body 42 via multiple legs 44, and a small gap is secured between the lower surface of the upper mold body 42 and the core mold portion 43. The core mold portion 43 is primarily a holding portion for temporarily holding or temporarily fastening the backing material 30 during foam molding of the pad 20, and has a shape that roughly corresponds to the shape of the backing material 30. For example, one end (the upper end in FIG. 4) of the core mold portion 43 is provided with a hook portion 43a (engagement portion) for hooking (engaging) the folded portion 32 of the backing material 30 using the aforementioned gap. Furthermore, one end (the upper end in FIG. 4) of the core mold portion 43 is provided with a through-hole forming portion 43b near the hook portion 43a. The through-hole forming portion 43b of the core mold portion is a portion (protrusion) that engages with the through-hole corresponding lining portion 33 of the back surface material 30 before foam molding and ultimately forms the through-hole 25 of the pad during foam molding.

[0033] When the molding die 40 is closed, the core mold portion 43 of the upper die 41 enters the molding recess 48 of the lower die 46, and the lower surface 42a of the upper die approaches the upper surface 47 of the lower die, thereby forming a cavity for pad molding between the inner wall surface of the molding recess 48 and the core mold portion 43.

[0034] [Manufacturing procedure for foam molded products] The seat pad 10 (FIG. 1) as a foam molded body is manufactured through a series of procedures or steps described below.

[0035] Preparation process: 2, 3, and 5(A) is prepared. As described above, this backing material 30 is a backing material on which perforations 34 are formed as intended separation portions D for separating a portion of the backing material later.

[0036] Set process: The back surface material 30 is set on the upper mold 41 of the mold in the open state. More specifically, the back surface material 30 is aligned and superimposed on the surface of the core mold portion 43 of the upper mold 41, and the folded portion 32 of the back surface material is hooked onto the hook portion 43a of the core mold portion. During this hooking operation, the folded portion 32 of the back surface material must be inserted into the gap between the upper mold main body portion 42 and the core mold portion 43, so the folded portion 32 is positioned in a position that is invisible (or difficult to see) to the worker. However, the separation portion D formed on the folded portion 32 of the back surface material remains connected and not separated or separated at this setting stage. In other words, the entire folded portion 32 maintains its integrity as a single piece of fabric. Therefore, even in conditions where it is difficult for the worker to see, the entire folded portion 32 can be easily set in the correct position on the core mold portion 43.

[0037] As shown in the comparative example of FIG. 5(B), if the folded portion 32 of the backing material were provided with a separation portion-corresponding portion 36 as a "cut-out portion" corresponding to the separation portion 24 of the pad 20, rather than with a perforation 34, most of the folded portion 32 would exist as a fin portion 37 adjacent to the separation portion-corresponding portion 36. In this case, even if an attempt is made to hook the folded portion 32 (fin portion 37) onto the hook portion 43a of the core mold portion, the fin portion 37 would flutter or bend, making it impossible to properly set it in the predetermined position of the core mold portion 43. Setting the fin portion 37 in the correct position may require visual confirmation even under conditions that make it difficult to see, significantly reducing work efficiency. In this regard, the folded portion 32 of the backing material in this embodiment maintains its overall integrity through the perforation 34 as a separation-intended portion, and does not have a portion difficult to control the positioning of, such as the fin portion 37. This significantly improves work efficiency, at least compared to the comparative example.

[0038] Injection process: A foamable raw material is injected into the molding recess 48 of the lower mold 46 of the mold in the open state. The foamable raw material may be a polyurethane foam raw material composition (for example, a mixture of polyisocyanate, polyol, catalyst, and blowing agent).

[0039] Foam molding process: The upper mold 41 is closed against the lower mold 46, and the cavity of the molding die 40 is filled with the foamable raw material. The foamable raw material then undergoes a chemical reaction (specifically, a resinification reaction and a foaming reaction) and foams, producing a polyurethane foam. The polyurethane foam then molds a pad 20 having a shape corresponding to the internal shape of the cavity, and the backing material 30 is integrated with the molded pad 20. In this way, the seat pad 10 is formed as a foam molded body. After the foam molding is completed and the mold is opened, the foam molded body 10 is separated from the lower mold 46 together with the core mold portion 43, and the foam molded body (seat pad) 10 is then removed from the molding die 40 (core mold portion 43).

[0040] Regarding the separation period for planned separation section D: At any of the following times (a), (b), and (c), the perforation 34 (the portion to be separated) of the backing material 30 is broken, and a part of the backing material 30 (the folded portion 32) is separated or divided along the perforation 34. That is, (a) The timing after the back surface material 30 is set in the upper mold 41 of the molding die For example, after the back surface material 30 is set in the core mold part 43 of the upper mold, at the timing when the upper mold 41 is closed to the lower mold 46, the back surface material 30 is separated along the perforations 34 by using the pressing force or clamping force at the time of mold closing. (b) Timing after foam molding of the pad 20 is completed For example, at the same time as or after the foam molding of the pad 20 is completed and the mold 40 is opened, the backing material 30 is separated along the perforations 34 using a special tool. (c) Timing for Removing the Foam Molded Article 10 from the Mold 40 For example, when the through-hole 25 is removed from the core mold portion 43, the back surface material 30 is separated along the perforations .

[0041] Needless to say, removing the foamed molded article (seat pad) from the mold after separating the backing material along the perforations 34 makes it easier to deform the product and remove it from the mold.

[0042] Contrary to the case described in the previous paragraph, it is also possible to obtain a foam molded body (seat pad) by removing the product from the mold 40 without separating the perforations 34, that is, by removing the product while leaving the perforations 34. In this case, the foam molded body (seat pad) obtained will have the following structure:

[0043] [Foam molded product 1] A foam molded article comprising a pad (20) made of a foam material and a backing material (30) integrally fixed to the back side of the pad to reinforce the pad, The back surface material has a separation-intended portion (D) for separating a portion of the back surface material later, and the separation-intended portion remains in an unseparated, connected state when foam molding of the foam molded product is completed. [Foam molding part 2] Preferably, in the foam molded article No. 1, the pad (20) is provided with a separation portion (24) as a recess or void at a position corresponding to the intended separation portion of the backing material.

[0044] According to the foam molded articles No. 1 and No. 2, the intended separation portion can be separated (or divided) as necessary to obtain a desired foam molded article.

[0045] [Effects of the embodiment] According to this embodiment, the backing material 30 used has perforations 34 as a separation-intended portion D for separating (or dividing) a portion thereof later, and when the backing material 30 is set in the upper mold 41 of the molding die, the separation-intended portion is in an unseparated, connected state. Therefore, compared to conventional backing materials in which a portion of the backing material 30 is already separated when set, the backing material 30 is easier to handle in the setting step, and the entire backing material 30 can be set correctly in the desired position on the molding die 40. On the other hand, the portion of the backing material 30 (separation-intended portion D) can be separated (or divided) later in a step or at a timing subsequent to the setting step, and therefore, a foam-molded product can be obtained in which a portion (desired portion) of the backing material is separated.

[0046] [Example of change] The present invention is not limited to the embodiment shown in FIGS. 1 to 5, and can be modified and implemented in the following manner.

[0047] 3 and 5(A), the separation portion D is formed as perforations 34. However, instead of perforations, the separation portion D may be configured as a linear portion or groove portion that is relatively thinner than the surrounding portion (of the separation portion D). In other words, the separation portion D in the present invention may be formed to be weaker than the other portions of the back surface material 30 other than the separation portion D, so that it can be separated or divided afterwards.

[0048] In the above-described embodiments of FIGS. 3 and 5(A), the entire separation portion D is formed by the perforation 34. However, the separation portion D may be configured as shown in FIG. 6. That is, the entire length of the separation portion D is divided into approximately two equal parts, and approximately half of the divided length located closer to the end edge 32a of the folded-back portion is configured by the perforation 34, while the remaining approximately half (i.e., approximately half located closer to the base of the folded-back portion) is configured by the slit 35. In this way, by adopting a hybrid configuration of "separation portion D = perforation 34 + slit 35," the length of the perforation 34 is shortened. As a result, it becomes easier to break the perforation 34 (i.e., to separate a portion of the backing material) when separating the sheet along the perforation 34 later. [Explanation of symbols]

[0049] 10 Seat pad (foam molded body) 20 pads 22 Pad fold 24 Separation (recess or void) 30 Backing material 32 Folded part of backing material 32a Edge of folded part 34 Perforation (to be separated) 35 Slit (to be separated) 40 mold 41 Upper mold (first mold) 46 Lower mold (second mold) D Separation section

Claims

1. A method for producing a foam molded article in which a pad made of a foam material and a backing material fixed to a back side of the pad are integrated, using a molding die having first and second dies capable of forming a cavity when the die is closed, comprising: a preparation step of preparing a backing material for reinforcing the pad, the backing material having a separation portion formed thereon for separating a portion of the backing material later; a setting step of setting the back surface material in a first mold of the molding die; an injection step of injecting a foamable raw material into a second mold of the molding die; a foam molding step of closing the first mold against the second mold, filling a foamable raw material into a cavity of the molding mold, foaming the foamable raw material to form a pad, and integrating the backing material with the pad to obtain a foam molded article; A method for producing a foamed molded article, comprising:

2. The method for producing a foam molded article according to claim 1, wherein at least a part of the separation portion of the back surface material is formed by perforations.

3. The method for producing a foam molded article according to claim 1, wherein a part of the back surface material is separated along the intended separation portion at a timing after the setting step or the foam molding step.

4. 2. The method for producing a foam molded article according to claim 1, wherein the back surface material prepared in the preparation step has a folded portion that is positioned in a position that is not visible to an operator when the back surface material is set in the first mold, and the intended separation portion is formed in the folded portion.

5. A back surface material used in the method for producing the foam molded article according to any one of claims 1 to 4, A backing material characterized in that it has a separation-intended portion for separating a part of the backing material later, and the separation-intended portion can maintain an unseparated connected state at least until the backing material is set in a molding die.

6. A pad made of a foam material; a backing material integrally fixed to the back side of the pad to reinforce the pad; In a foamed molded article comprising: A foam molded article, characterized in that the back surface material has a separation-intended portion for later separation of a part of the back surface material, and the separation-intended portion remains in an unseparated connected state when foam molding of the foam molded article is completed.

7. 7. The foam molded article according to claim 6, wherein the pad is provided with a separation portion as a recess or a void at a position corresponding to the intended separation portion of the backing material.

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