Seat pad and method for manufacturing a seat pad

Abstract

To provide a seat pad in which deformation of a hollow body buried in a foam body is suppressed, and a seat pad manufacturing method to acquire the seat pad.SOLUTION: A seat pad 1 includes a resin hollow body 10 and a foam body F in which the hollow body 10 is buried. The hollow body 10 is formed with one or more holes A10, and the one or more holes A10 are formed so that a condition of 10≤S / V (S: total area of the hole, V: content volume of the hollow body) is satisfied. A seat pad manufacturing method includes: a hollow body arrangement process for arranging the hollow body 10 in a cavity formed by closing a mold using the hollow body 10; and a foam body forming process for forming the foam body by foaming resin supplied in the cavity after the hollow body arrangement process.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a seat pad and a method for manufacturing the seat pad.

Background Art

[0002] Among conventional seat pads, there is a seat pad with a resin duct embedded therein (see, for example, Patent Document 1). The seat pad with the duct is foam-molded by closing the air intake of the duct with a sealing tape and closing the air outlet of the duct with a raised portion provided in the lower mold.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when foam-molding is performed with the inside of a resin hollow body closed as in the above seat pad with a duct, the hollow body may be deformed.

[0005] An object of the present invention is to provide a seat pad in which deformation of a resin hollow body embedded in a foam is suppressed, and a method for manufacturing the seat pad for obtaining the seat pad.

Means for Solving the Problems

[0006] The seat pad according to the present invention has a resin hollow body and a foam in which the hollow body is embedded, and one or more holes are formed in the hollow body, and the one or more holes satisfy: 10≦S / V···(1) S: Total area of the holes (square centimeters), V: Internal volume of the hollow body (liters) It is formed to satisfy the conditions. According to the present invention, the sheet pad is formed in which the deformation of the resin hollow body embedded in the foam is suppressed.

[0007] In the seat pad according to the present invention, the one or more holes are S / V ≤ 30 ···(2) It is preferable that the sheet pad is formed to satisfy the following conditions. In this case, the deformation of the hollow resin body is more suppressed.

[0008] In the seat pad according to the present invention, it is preferable that the hollow body has two opposing walls, and further, that the hollow body has support columns inside to support the two opposing walls. In this case, the deformation of the resin hollow body is further suppressed in the seat pad.

[0009] In the sheet pad according to the present invention, it is preferable that the hollow body has ribs extending along the surface of the hollow body. In this case, the deformation of the resin hollow body is further suppressed in the sheet pad.

[0010] A method for manufacturing a sheet pad according to the present invention is a method for manufacturing a sheet pad having a hollow body made of resin and a foam in which the hollow body is embedded, comprising: a hollow body placement step of placing the hollow body in a cavity formed by closing a mold, and after the hollow body placement step, foaming the resin supplied to the cavity. The process includes a foam forming step of forming the foam by and the hollow body having one or more holes formed therein, 10 ≤ S / V ···(1) S: Total area of ​​the holes (square centimeters), V: Internal volume of the hollow body (liters) It is formed to satisfy the following conditions. According to the method for manufacturing a sheet pad according to the present invention, a sheet pad can be obtained in which the deformation of the resin hollow body embedded in the foam is suppressed.

[0011] In the method for manufacturing a sheet pad according to the present invention, the one or more holes are S / V ≤ 30 ···(2) It is preferable that the sheet pad is formed to satisfy the following conditions. In this case, a sheet pad can be obtained in which the deformation of the resin hollow body is more suppressed.

[0012] In the method for manufacturing a sheet pad according to the present invention, in the hollow body arrangement step, it is preferable that the holes be positioned at a location that does not coincide with the supply port through which the resin is supplied. In this case, a decrease in the density of the foam can be suppressed and the total area of ​​the holes can be secured.

[0013] In the method for manufacturing a sheet pad according to the present invention, in the hollow body arrangement step, it is preferable that the holes are positioned at a location that does not coincide with the mating surface of the mold. In this case, a sheet pad can be obtained in which the deformation of the resin hollow body is further suppressed.

[0014] In the method for manufacturing a seat pad according to the present invention, it is preferable that the hollow body has two opposing walls, and further, that the hollow body has support columns inside that support the two opposing walls. In this case, a seat pad can be obtained in which the deformation of the resin hollow body is further suppressed.

[0015] In the method for manufacturing a sheet pad according to the present invention, it is preferable that the hollow body has ribs extending along the surface of the hollow body. In this case, a sheet pad can be obtained in which the deformation of the resin hollow body is further suppressed. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide a sheet pad in which the deformation of a hollow body embedded in a foam is suppressed, and a method for manufacturing the sheet pad to obtain the sheet pad. [Brief explanation of the drawing]

[0017] [Figure 1]It is a perspective view schematically showing a seat pad according to an embodiment of the present invention. [Figure 2] It is a cross-sectional view showing the seat pad of FIG. 1 in a cross-section taken along line A-A of FIG. 1. [Figure 3] It is a perspective view showing an example of a hollow body applicable to the seat pad of FIG. 1. [Figure 4] It is a plan view of the hollow body of FIG. 3. [Figure 5] It is a perspective view showing the hollow body of FIG. 3 corresponding to a cross-section taken along line B-B of FIG. 4. [Figure 6] It is another perspective view showing the hollow body of FIG. 3 corresponding to a cross-section taken along line B-B of FIG. 4. [Figure 7A] It is a cross-sectional view schematically showing a molding die that can be used in a method for manufacturing a seat pad according to an embodiment of the present invention in a state before mold clamping. [Figure 7B] It is a cross-sectional view schematically showing a mold clamping state of the molding die of FIG. 5A.

Mode for Carrying Out the Invention

[0018] [[ID=​​​​​​​​​​The cushion pad 2 has a center pad portion 2a and side pad portions 2b located on both the left and right sides of the center pad portion 2a. The center pad portion 2a is configured to support the seated person's buttocks and thighs from below. The two side pad portions 2b are configured to support the seated person's buttocks and thighs from both the left and right sides.

[0021] The back pad 3 also has a center pad portion 3a and side pad portions 3b located on both the left and right sides of the center pad portion 3a. The center pad portion 3a is configured to support the seated person's back and waist from the rear. The two side pad portions 2b are configured to support the seated person's back and waist from both the left and right sides.

[0022] Referring to Figure 2, in the sheet pad 1 according to this embodiment, the cushion pad 2 has a hollow body 10 made of resin and a foam body F in which the hollow body 10 is embedded, and one or more holes A10 are formed in the hollow body 10.

[0023] In this embodiment, the foam F is composed of a foamed resin. The foamed resin is formed by foaming a resin. Examples of the resin include polyurethane. Flexible polyurethane is preferred as the polyurethane. However, according to the present invention, various foamable resins can be used as the resin.

[0024] In this embodiment, the hollow body 10 is a bulking material with a specific gravity lighter than the foam F. The bulking material is embedded in the foam F for the purpose of reducing the weight of the sheet pad. In this embodiment, the hollow body 10 is a blow-molded product made of resin. The hollow body 10 is positioned close to the back surface (bottom surface) 2f of the cushion pad 2 (sheet pad). In this embodiment, the outer surface 10f of the hollow body 10 and the back surface 2f of the cushion pad 2 coincide. That is, in this embodiment, the hollow body 10 is embedded in the foam F so as to form a part of the back surface 2f of the cushion pad 2. An internal space S10 is formed inside the hollow body 10. Hole A10 is a through hole formed in the hollow body 10. Hole A10 allows the internal space S10 to be connected to the outside. The hollow body 10 is embedded in the foam F such that the hole A10 opens toward the back surface (bottom surface) 2f of the cushion pad 2 (sheet pad). The resin constituting the hollow body 10 is, for example, polypropylene (PP). However, according to the present invention, various resins can be used as the resin.

[0025] There may be at least one hole A10. However, the hole A10 is formed to satisfy the condition of the following equation (1).

[0026] 10 ≤ S / V ···(1) S: Total area of ​​hole A10 (square centimeters), V: Internal volume of hollow body 10 (liters)

[0027] The total area S is the opening area S1 of a single hole A10 if there is one hole A10. If there are multiple holes A10, it is the sum of the opening areas S1 of all holes A10. For example, if hole A10 is a circular hole with radius r1, the opening area S1 = π × r 2 The unit of total area S is square centimeters (cm²). 2 )

[0028] The internal volume V is the volume of the internal space S10 of the hollow body 10. The internal space S10 is the closed space before the hole A10 is formed. The unit of the internal volume V is liters (L).

[0029] Figures 3 to 6 show an example of a hollow body 10 applicable to the seat pad 1. In this embodiment, the hollow body 10 is embedded in the foam F of the cushion pad 2.

[0030] Referring to Figure 3, the hollow body 10 has two opposing walls 11 and a side wall 12 connected to the two opposing walls 11. The internal space S10 of the hollow body 10 is an internal space partitioned by the two opposing walls 11 and the side wall 12 (see, for example, Figures 5 and 6).

[0031] In this embodiment, the hollow body 10 has a rectangular parallelepiped external shape. Specifically, as shown in Figure 4, the external shape of the two opposing walls 11 is rectangular in plan view. Also, in this embodiment, the side wall 12 includes four side walls 12. Referring to Figure 3, the four side walls 12 are each formed by two inclined walls 12A that incline outward from one opposing wall 11 to the other opposing wall 11. In this embodiment, the confluence of the two inclined walls 12A is formed by a flange 12F that encircles the hollow body 10 along the four side walls 12. In this embodiment, the flange 12F is located at the center of the thickness direction of the hollow body 10. Here, the thickness direction of the hollow body 10 is the direction in which the perpendiculars of the two opposing walls 11 extend.

[0032] Furthermore, referring to Figure 5, the hollow body 10 has support columns 13 inside the hollow body 10 that support the two opposing walls 11. The support columns 13 mechanically increase the rigidity of the hollow body 10 in the thickness direction by supporting the two opposing walls 11. This mechanically increases the rigidity of the hollow body 10. Therefore, according to the hollow body 10 of this embodiment, the provision of support columns 13 suppresses compressive deformation that may occur between the two opposing walls 11.

[0033] In this embodiment, the hollow body 10 is embedded in the foam F such that when the seat pad 1 is attached to the vehicle, the two opposing walls 11 are positioned facing each other in the vertical direction. In this case, the support column 133 extends along the vertical direction. As a result, the hollow body 10 has excellent rigidity against vertical loads and compression deformation in the vertical direction is suppressed. In addition, in this embodiment, the support column 13 has a boss hole A13. The boss hole A13 is filled with foam F. As a result, the hollow body 10 is firmly embedded in the foam F. Furthermore, the boss hole A13 reduces the amount of resin used in the support column 13. This makes it possible to reduce the weight of the hollow body 10.

[0034] Referring to Figure 6, in this embodiment, the support column 13 has a waist portion 13a at an intermediate position along the extending axis O13 of the support column 13 (which is parallel to the vertical axis when the seat pad 1 is attached to the vehicle). The area of ​​the support column 13 in a cross-sectional area perpendicular to the support column 13 is smallest at the waist portion 13a. Here, the cross-sectional area of ​​the support column 13 is the cross-sectional area of ​​the support column 13 when the cross-section is a plane perpendicular to the extending axis O13 of the support column 13. As in this embodiment, when a constriction is formed such that the cross-sectional area of ​​the waist portion 13a is the smallest along the extending axis O13 of the support column 13, a large internal volume (volume of the internal space S10) of the hollow body 10 can be secured. However, according to the present invention, the support column 13 can be a straight support column of the same diameter along the extending axis O13 of the support column 13. Alternatively, according to the present invention, the support column 13 can also be shaped to form a bulge such that the cross-sectional area of ​​the waist portion 13a is the largest among the extensional axis O13 of the support column 13.

[0035] Furthermore, referring to Figure 6, the hollow body 10 extends along the surface of the hollow body 10. It has ribs 14. The ribs 14 mechanically increase the rigidity of the opposing wall 11 or side wall 12 on which the ribs 14 are provided. This mechanically increases the rigidity of the hollow body 10. Therefore, according to the hollow body 10 of this embodiment, the compression deformation of the hollow body 10 is suppressed by providing the ribs 14.

[0036] In this embodiment, the rib 14 is a concave rib that is recessed toward the internal space S10. In this case, since the rib 14 does not protrude from the outer surface of the hollow body 10, the rigidity of the hollow body 10 can be increased while suppressing an increase in the size of the hollow body 10. Also in this embodiment, the rib 14 is formed in a shape in which the hollow body 10 is bent into a concave shape, as shown in Figure 6, for example. In this case, the rigidity of the hollow body 10 can be increased while suppressing the thickness of the hollow body 10. That is, in this case, the amount of resin used in the hollow body 10 can be reduced, the weight of the hollow body 10 can be reduced, and the rigidity of the hollow body 10 can be increased. However, according to the present invention, the rib 14 can be a convex rib that protrudes toward the opposite side of the internal space S10 (the outer surface side of the hollow body 10). The convex rib 14 can also be formed in a shape in which the hollow body 10 is bent into a convex shape.

[0037] In this embodiment, the ribs 14 extend along the surface of the opposing wall 11 and the surface of the side wall 12. In this embodiment, the ribs 14 are connected to the support portions 13 on the opposing wall 11. More specifically, the ribs 14 are connected to each of the boss holes A13 of adjacent support portions 13. In addition, in this embodiment, the ribs 14 extend in the thickness direction of the hollow body 10 on the side wall 12 (the direction in which the two opposing walls 11 face each other, more specifically in this embodiment, the direction in which the support portions 13 extend). Furthermore, in this embodiment, the ribs 14 on the side wall 12 are connected to the ribs 14 on the opposing wall 11. Referring to Figure 4, the ribs 14 are formed in a grid pattern on the opposing wall 11 in a plan view. Also referring to Figure 4, the support portions 13 are located on the intersections where the two ribs 14 meet.

[0038] In this embodiment, the hollow body 10 has increased rigidity of the entire opposing wall 11 by arranging a plurality of support columns 13 in the central part of the opposing wall 11. Furthermore, the hollow body 10 has a plurality of small regions R11 that are partitioned by a plurality of ribs 14. Dividing the opposing wall 11 into a plurality of small regions R11 as in this embodiment increases the rigidity of each of the small regions R11. Therefore, according to the hollow body 10 in this embodiment, by arranging a plurality of support columns 13 in the central part of the opposing wall 11 and partitioning the opposing wall 11 into a plurality of small regions R11 by a plurality of ribs 14, pressure deformation (deformation caused by pressure applied to the hollow body 10, for example, compression deformation) that may occur in the entire opposing wall 11 can be effectively suppressed. In addition, the hollow body 10 can have increased rigidity in the thickness direction (the direction in which the support columns 13 extend: the direction along the axis O13) because the ribs 14 extend across the side wall 12. Therefore, the hollow body 10 can effectively suppress pressure deformation of the hollow body 10 (particularly compressive deformation in the thickness direction of the hollow body 10).

[0039] In this embodiment, the hole A10 is formed in one of the multiple sub-regions R11 partitioned by the opposing wall 11. However, according to the present invention, the hole A10 can be formed in each of at least two or more of the multiple sub-regions R11. Furthermore, according to the present invention, multiple holes A10 may be formed in a single sub-region R11.

[0040] Furthermore, the holes A10 can be formed in, for example, the ribs 14. In this case, the holes A10 can be formed in each of the multiple ribs 14. Also, according to the present invention, multiple holes A10 may be formed in a single rib 14.

[0041] According to the present invention, the hole A10 can be formed at any position in the hollow body 10. Furthermore, when the foam F of the cushion pad 2 is molded in the mold, it is preferable that the hole A10 is positioned so as not to coincide with the resin supply port for forming the foam F. In this embodiment, the flange 12F of the hollow body 10 corresponds to the portion of the mating surface of the mold formed at the position of the mating surface of the mold. In this embodiment, the hole A10 is positioned to avoid the flange 12F.

[0042] In conventional sheet pads, the internal space of the hollow body was a closed space, enclosed from the outside world within the mold during the integral foaming process. However, when the hollow body is placed in the cavity of the mold with its interior closed and then foamed, there was a risk of deformation occurring in the hollow body for reasons described later.

[0043] (During foam molding) After placing a hollow body in the cavity of a mold, when resin M, which is the raw material for forming a foam, is supplied to the cavity and foamed, the pressure inside the cavity rises due to the foaming pressure of the resin (hereinafter also referred to as "supplied resin") M. This pressure rise can cause deformation of the hollow body placed inside the cavity. When the supplied resin foams inside the cavity, the temperature inside the cavity rises due to the foaming heat of the supplied resin M. This temperature rise can also cause deformation of the hollow body. Therefore, when a hollow body is used as an insert in foam molding, the hollow body, which has been heated by the foaming heat, is subjected to the increased pressure inside the cavity due to the foaming pressure, which can cause deformation of the hollow body.

[0044] (After foam molding) Immediately after molding, a foam has many of its cell membranes closed, and therefore, the foam may shrink over time after molding. Conventionally, to prevent shrinkage, the foam is crushed (bubble broken) to open the cell membranes. Crushing is generally performed under vacuum or near-vacuum conditions. In this case, the hollow body, along with the foam, may deform due to the negative pressure (pressure close to vacuum) generated during the crushing process.

[0045] In contrast, according to the sheet pad 1 of this embodiment, as shown in Figure 2, the hollow body 10 embedded in the foam F of the cushion pad 2 has at least one hole A10. That is, in this embodiment, the hollow body 10 is an open space with an open internal space S10. In addition, the hole A10 is 10 ≤ S(cm) in the above formula (1). 2 It is formed to satisfy the relationship ) / V(L). If the hole A10 is formed to satisfy the relationship in equation (1) above, the pressure in the internal space S10 and the pressure in the cavity will be kept in a state close to equilibrium through the hole A10.

[0046] According to the sheet pad 1 of this embodiment, when molding the foam F of the cushion pad 2, even when the pressure inside the cavity rises due to the foaming pressure of the supplied resin M, the internal pressure of the hollow body 10 (pressure in the internal space S10) remains close to equilibrium with the foaming pressure generated inside the cavity. Therefore, the sheet pad 1 can suppress pressure deformation (e.g., compression deformation) of the hollow body 10 caused by the pressure rise inside the cavity during the molding of the foam F. In particular, when molding the foam F, the temperature of the cavity rises due to the foaming heat of the supplied resin M, and the hollow body 10 is prone to softening due to this temperature rise. Therefore, as in this embodiment, if the internal pressure of the hollow body 10 is close to equilibrium with the foaming pressure generated in the cavity, the pressure difference between the pressure received from the outside of the hollow body 10 (pressure in the cavity) and the internal pressure of the hollow body 10 is suppressed, even when the hollow body 10 is softened. Thus, the sheet pad 1 according to this embodiment is effective in suppressing pressure deformation of the hollow body 10 caused by the rise in pressure in the cavity.

[0047] Furthermore, according to the sheet pad 1 of this embodiment, even when the sheet pad 1 is placed in the crushing state after molding, the internal pressure of the hollow body 10 is close to equilibrium with the pressure (vacuum pressure) around the hollow body 10. Therefore, the sheet pad 1 can suppress pressure deformation (e.g., expansion deformation) of the hollow body 10 caused by pressure changes around the hollow body 10 after molding of the foam F.

[0048] Therefore, according to the sheet pad 1, the deformation of the resin hollow body 10 embedded in the foam F is suppressed, resulting in a sheet pad.

[0049] Furthermore, in the sheet pad 1 according to this embodiment, the hole 1 is formed to satisfy the conditions of the following formula (2).

[0050] S / V ≤ 30 ···(2)

[0051] In this case, the supplied resin M is less likely to flow into the hole A10, making it less likely to block the hole A10. Therefore, in this case, the deformation of the resin hollow body 10 is more suppressed in the sheet pad. Also, in this case, because the size of the hole A10 is small relative to the internal volume V of the hollow body 10, there are fewer constraints on the installation location when installing the hole A10 on the hollow body 10. This makes it possible to install the hole A10 in a location where the supplied resin M is less likely to flow from the beginning, and it is easier to maintain the mechanical strength of the hollow body 10. The internal volume V of the hollow body 10 can be maintained because the supplied resin M is less likely to flow into the hole A10.

[0052] Furthermore, referring to Figure 6, for example, in this embodiment, the hollow body 10 has two opposing walls 11, and furthermore, the hollow body 10 has a support column 13 inside that supports the two opposing walls 11. In this case, the mechanical rigidity of the hollow body 10 is improved by the support column 13. Therefore, in this case, the deformation of the resin hollow body 10 is further suppressed in the seat pad.

[0053] Furthermore, in this embodiment, the hollow body 10 has ribs 14 extending along the surface of the hollow body 10. In this case, the mechanical rigidity of the resin hollow body 10 is improved by the ribs 14. Therefore, in this case, the deformation of the hollow body 10 is more suppressed in the resulting seat pad.

[0054] [Method of manufacturing a seat pad] The method for manufacturing a sheet pad according to this embodiment is a method for manufacturing a sheet pad having a hollow body 10 made of resin and a foam body F in which the hollow body 10 is embedded. The method for manufacturing a sheet pad according to this embodiment includes a hollow body placement step of placing the hollow body 10 in a cavity C formed by closing a mold 100, and a foam body forming step of forming a foam body F by foaming a supply resin M supplied into the cavity C after the hollow body placement step. The hollow body 10 has one or more holes A10 formed therein, and the one or more holes A10 are formed to satisfy the conditions of formula (1).

[0055] The method for manufacturing a seat pad according to this embodiment will be described below with reference to Figures 7A and 7B. The method for manufacturing a seat pad according to this embodiment will be described as a method for manufacturing a cushion pad to obtain the cushion pad 2.

[0056] Figure 7A schematically shows a mold 100 usable in a sheet pad manufacturing method according to one embodiment of the present invention in its state before clamping. Figure 7B schematically shows the mold 100 in its clamped state.

[0057] Referring to Figure 7B, reference numeral 100 denotes a mold for obtaining the cushion pad 2. The mold 100 comprises an upper mold 101 located above the mold 100 and a lower mold 102 located below the mold 100. The inner surface 100f of the mold 100 is formed by the inner surface 101f of the upper mold 101 and the inner surface 102f of the lower mold 102. That is, in this embodiment, the cavity C formed in the mold 100 is formed by the inner surface 101f of the upper mold 101 and the inner surface 102f of the lower mold 102.

[0058] (Hollow body placement process) Referring to Figure 7A, in the hollow body placement step, after opening the upper mold 101 and the lower mold 102, the hollow body 10 described above, for example using Figures 3 to 6, is placed between the upper mold 101 and the lower mold 102. The hollow body 10 can be positioned relative to the lower mold 102 by, for example, a holding portion (not shown) formed on the inner surface 102f of the lower mold 102. Next, as shown in Figure 7B, the upper mold 101 and the lower mold 102 are combined to form a cavity C inside the molding die 100. As a result, the hollow body 10 is positioned in a predetermined location within the cavity C. In this embodiment, in the hollow body placement step, the hole A10 of the hollow body is positioned at a location that does not coincide with the supply port (not shown) to which the supply resin M is supplied. In this embodiment, the supply port is located in the lower mold 102. That is, the supply resin M is supplied from the side of the lower mold 102, and the supply resin M foams from the lower mold 102 toward the upper mold 101. In this embodiment, the hollow body 10 is set in the cavity C so as to be positioned closer to the upper mold 101 than to the lower mold 102. Furthermore, the hollow body 10 is set in the cavity C so as to be positioned so that the hole A10 faces the upper mold 101. As in this embodiment, by positioning the hollow body 10 close to the upper mold 101 and positioning the hole A10 toward the upper mold 101, the hole A10 will automatically not face the supply port. Thus, in this embodiment, the hole A10 is automatically positioned so as not to coincide with the supply port. In other words, according to the present invention, if the hollow body 10 is positioned close to the upper mold 101 (lower mold 102) in the lower mold 102 (upper mold 101) where the supply port is located, and the hollow body 10 is positioned so that the hole A10 faces the upper mold 101 (lower mold 102), then the hole A10 is automatically positioned so as not to coincide with the supply port. Furthermore, in this embodiment, in the hollow body positioning step, the hole A10 of the hollow body is positioned so as not to coincide with the mating surface between the upper mold 101 and the lower mold 102 of the molding die 100 (see Figure 7B).

[0059] (Foam formation process) After the hollow body placement process, the upper mold 101 and lower mold 102 of the mold 100 are joined together and closed, and the supply resin M is injected into the cavity C. The supply resin M foams within the cavity C, forming a foam F that covers the hollow body 10 within the cavity C. Next, the upper mold 101 and lower mold 102 are opened and the foam F in which the hollow body 10 is embedded is removed. This makes it possible to obtain a cushion pad 2 in which the hollow body 10 is embedded in the foam F.

[0060] The hollow body 10 used in this embodiment is an open space in which the internal space S10 is opened by the hole A10. In addition, the hole A10 is 10 ≤ S(cm) in the above equation (1). 2 The structure is formed to satisfy the relationship ) / V(L). In this case, when the mold 100 is closed, even when the temperature of the cavity rises due to the foaming heat of the supplied resin M and the pressure of the cavity rises due to the foaming pressure of the supplied resin, the pressure in the internal space S10 and the pressure in the cavity are maintained in a state close to equilibrium through the hole A10. That is, according to the sheet pad manufacturing method of this embodiment, even when the pressure of the cavity C, which has risen due to the foaming pressure, is applied to the hollow body 10 heated by the foaming heat, the internal pressure of the hollow body 10 remains in a state close to equilibrium with the foaming pressure generated in the cavity. Therefore, according to the sheet pad manufacturing method of this embodiment, pressure deformation (e.g., compression deformation) of the hollow body 10 caused by the pressure rise in the cavity C can be suppressed.

[0061] Therefore, according to the sheet pad manufacturing method of this embodiment, a cushion pad 2 can be obtained in which the deformation of the resin hollow body 10 embedded in the foam F is suppressed.

[0062] Furthermore, in this embodiment, the hole A10 is formed to satisfy the conditions of formula (2) above. In this case, the supply resin M is less likely to flow into the hole A10, making it less likely to block the hole A10. As a result, a sheet pad can be obtained in which the deformation of the resin hollow body 10 is further suppressed.

[0063] Furthermore, in the hollow body placement step in this embodiment, the hole A10 is positioned so as not to coincide with the supply port through which the supplied resin M is supplied when the hollow body 10 is placed in the cavity C. In this case, it is possible to make it difficult for the supplied resin M to flow into the internal space S10 through the hole A10. If the hole A10 coincides with the supply port, it is possible that the supplied resin M will reach the hole A10 in a low viscosity state. In this case, it is possible that the supplied resin M will unintentionally enter the hole A10. The entry of the supplied resin M will cause a decrease in the density of the foam F and a decrease in the total area of ​​the hole A10. The decrease in the density of the foam F will affect the cushioning properties, and the decrease in the total area of ​​the hole A10 will affect the suppression of deformation of the hollow body 10. In contrast, as in this embodiment, if the hole A10 is not aligned with the supply port, it is possible to prevent the supplied resin M from entering the hole A10. This prevents the supplied resin M from unintentionally entering the holes A10, and as a result, prevents the supplied resin M from blocking the holes A10. Therefore, in this case, the decrease in density of the foam F can be suppressed while ensuring the total area of ​​the holes A10.

[0064] Furthermore, in the hollow body arrangement step in this embodiment, the hole A10 is positioned at a location that does not coincide with the mating surface of the mold 100. In this case, it becomes difficult for the supplied resin M to flow into the hole A10. Therefore, in this case, a sheet pad can be obtained in which the deformation of the resin hollow body is further suppressed.

[0065] Furthermore, in this embodiment, the hollow body 10 has two opposing walls 11, and also has support columns 13 inside the hollow body 10 that support the two opposing walls 11. In this case, the mechanical rigidity of the hollow body 10 is improved by the support columns 13. Therefore, in this case, a seat pad can be obtained in which the deformation of the resin hollow body 10 is further suppressed.

[0066] Furthermore, in this embodiment, the hollow body 10 has ribs 14 extending along the surface of the hollow body 10. In this case, the mechanical rigidity of the hollow body 10 is improved by the ribs 14. Therefore, in this case, a sheet pad can be obtained in which the deformation of the resin hollow body 10 is more suppressed.

[0067] Tables 1 and 2 below show the results of testing samples 101-120 of the hollow body 10 and evaluating the amount of permanent deformation that occurred in them.

[0068] [Table 1]

[0069] [Table 2]

[0070] Here, "hole diameter" refers to the diameter of hole A10. The unit of "hole diameter" is centimeters (cm). "Number" refers to the number of holes A10 formed in the hollow body 10. "Area" is indicated by "S". "S" is the total area (total opening area) of holes A10. The unit of "S" is square centimeters (cm). 2 ) is the case. "V" is the internal volume of the hollow body 10. The unit of "V" is liters (L). In this test, "V" is 0.92 L (liters). "X", "Y", and "Z" are the coordinate axis directions of the hollow body 10. "〇" is an evaluation result indicating that (almost) no permanent deformation has occurred. "×" is an evaluation result indicating that permanent deformation has occurred that makes it unsuitable for use. "△" is an evaluation result indicating that permanent deformation has occurred that makes it suitable for use.

[0071] In the above test, two samples with the same "hole diameter" and "number of holes" were treated as one pair, and a total of 10 pairs of samples (101-102, 103-104, 105-106, 107-108, 109-110, 111-112, 113-114, 115-116, 117-118, 119-120) were used to improve the accuracy of the test results.

[0072] Referring to Tables 1 and 2, it can be seen that in pairs of samples where both samples satisfy 10 ≤ S / V (107-108, 109-110, 111-112, 115-116, 117-118, 119-120), there was little permanent deformation observed in all coordinate axes of the hollow body 10.

[0073] The above describes exemplary embodiments of the present invention, and various modifications can be made without departing from the scope of the claims. For example, in this embodiment, the cushion pad 2 of the seat pad 1 was described, but the present invention can be applied to the back pad 3 or the headrest 4. Furthermore, the seat pad according to the present invention may include at least one of the cushion pad 2, the back pad 3, and the headrest 4. Also, the molding die 100 may include at least two parts, an upper mold 101 and a lower mold 102. In addition, the various configurations adopted in each of the above embodiments can be substituted for each other as appropriate. [Explanation of Symbols]

[0074] 1: Seat pad, 2: Cushion pad, 3: Back pad, 4: Headrest, 10: Hollow body, 11: Opposing wall, 12: Side wall, 12A: Inclined wall, 12F: Flange section, 13: Support section, 13A: Boss hole, 14: Rib, 100: Molding mold, 101: Upper mold, 102: Lower mold, A10: Hole, S10: Internal space, C: Cavity, F: Foam, M: Supply resin, R11: Small area

Claims

1. It comprises a hollow body made of resin and a foam in which the hollow body is embedded, and the hollow body has one or more holes formed therein. The one or more holes mentioned above are 10.2 ≤ S / V ≤ 27.3 ... (1) The structure is formed to satisfy the conditions that S is the total area of ​​the holes (square centimeters) and V is the internal volume of the hollow body (liters), and furthermore, the total area S of the holes is 9.4 ≤ S ≤ 25.1 ... (2) A seat pad that satisfies the following conditions.

2. The seat pad according to claim 1, wherein the hollow body has two opposing walls, and further has support columns inside the hollow body that support the two opposing walls.

3. The sheet pad according to claim 1 or 2, wherein the hollow body has ribs extending along the surface of the hollow body.

4. A method for manufacturing a sheet pad, comprising a hollow body made of resin and a foam in which the hollow body is embedded, A hollow body placement step involves placing the hollow body within a cavity formed by closing the mold, The process includes, after the hollow body arrangement step, a foam forming step in which the resin supplied into the cavity is foamed to form the foam, The hollow body has one or more holes formed in it. The one or more holes mentioned above are 10.2 ≤ S / V ≤ 27.3 ... (1) S: Total area of ​​the holes, V: Internal volume of the hollow body It is formed to satisfy the following conditions, and furthermore, the total area S of the holes is 9.4 ≤ S ≤ 25.1 ... (2) A method for manufacturing a seat pad that satisfies the relationship.

5. A method for manufacturing a sheet pad according to claim 4, wherein in the hollow body arrangement step, the hole is positioned at a location that does not coincide with the supply port through which the resin is supplied.

6. The method for manufacturing a sheet pad according to claim 5, wherein in the hollow body arrangement step, the hole is positioned at a location that does not coincide with the mating surface of the mold.

7. A method for manufacturing a sheet pad according to any one of claims 4 to 6, wherein the hollow body has two opposing walls, and further has support columns inside the hollow body that support the two opposing walls.

8. A method for manufacturing a sheet pad according to any one of claims 4 to 7, wherein the hollow body has ribs extending along the surface of the hollow body.

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