JP2020175253A - Method of manufacturing vehicle seat pad - Google Patents

Abstract

To provide a method of manufacturing a vehicle seat pad.SOLUTION: A method of manufacturing a vehicle seat pad in which at least a reception surface portion on a side contacting a passenger is formed of a front layer pad 4 of a soft polyurethane foamed molding comprises the steps of: setting a core pad 2 being a bead foamed molding and having a flange part 22 protruding toward the outer side from a side wall 21 on an upper die 9; injecting a foaming material g into a lower die cavity surface 81; interposing and mold-closing an outer flange part 23 on the tip side of the flange part 22 between the upper die 9 and a lower die 8; forming a reception surface portion on a design surface side; foam-molding a front layer pad 4 whose inner side opposite to the design surface side is integrally joined to the surface of the core pad 2 in the state where the outer flange part 23 extends from a lower edge joint part 221 contacting a lower edge 42a on the design surface side with respect to the front layer pad 4 of the flange part 22; and removing the outer flange part 23 along the lower edge joint part 221 from the seat pad having the outer flange part 23 after mold removal.SELECTED DRAWING: Figure 12

Description

The present invention relates to a method for manufacturing a vehicle seat pad constituting a vehicle seat.

The seat pads that make up the seats and backrests of vehicle seats such as automobiles have conventionally been made of flexible polyurethane foam moldings so as to provide comfortable cushioning. However, in recent years, there has been a movement to respond to the weight reduction of vehicles by carrying a part of them to bead foam molded products and the like. There is also a manufacturing method in which the bead foam molded product and the flexible polyurethane foam molded product are separately molded and then overlapped to form a seat pad, but in such a case, abnormal noise is generated from the overlapped surface. Therefore, an invention has been proposed in which a beaded foam molded product is used as an insert product to foam mold a flexible polyurethane foam molded product (for example, Patent Documents 1 and 2).

Japanese Patent No. 3474571 Japanese Unexamined Patent Publication No. 9-70330

The upper layer formed of the seat body of Patent Document 1 and the polyurethane foam of Patent Document 2 corresponds to the surface layer pad of the present invention, and the frame element and the patent document formed by the relatively high-density hard foam of Patent Document 1. The lower layer formed of the polyester foam of No. 2 corresponds to the core pad of the present invention.

However, the invention of Patent Document 1 states, "Once the frame and pelvis support element 104 are molded, the fixing portion 132 of each vehicle fixing means 112 is accepted in the gap 140 provided in the mold, as shown in FIG. In addition, this is put in the empty space 134 of the double door mold 136. ”After that, the process proceeds to injection of foam material, mold closing, and foam molding of the seat body, but when the frame is lifted from the mold, the back of the frame There is a problem that the foaming material wraps around. In Patent Document 2, due to the shape of the layered different hardness pad shown in FIG. 1, there is a possibility that the foamed raw material may wrap around to the back surface of the frame during foam molding of the upper layer.
Further, in recent seat pads, as described in paragraph 0018 of Japanese Patent Application Laid-Open No. 2015-173786, a locking portion 22 g is recessed on the back surface of the "back layer pad (core pad in the present invention) ...". As described above, the locking portion (groove for attaching the skin in the present invention) is provided, and when the core pad is lifted from the mold, the foamed raw material wraps around there. "A plurality of locking portions 22g are provided along the outer peripheral portion of the back surface of the back layer pad 22. " Therefore, when the foamed raw material wraps around to the back surface side in the foam molding of the surface layer pad, the locking portion is easily provided. It gets into the groove of. As a result, it is necessary to remove the troublesome burrs that have entered each of the numerous grooves.

The present invention solves the above problem by integrally molding the surface layer pad with the core pad so that the foamed raw material does not wrap around to the back surface side and does not stain the back surface side of the core pad. In addition, a groove for attaching the skin It is an object of the present invention to provide a method for manufacturing a vehicle seat pad without deburring work.

In order to achieve the above object, the gist of the invention according to claim 1 is in a method for manufacturing a vehicle seat pad in which at least a receiving surface portion on the side where an occupant comes into contact is formed of a surface pad of a flexible polyurethane foam molded body. A core pad, which is a foam molded body and has a flange portion protruding outward from the side wall, is set in the upper mold, and then a foaming material is injected into the lower mold cavity surface, and the outside of the flange portion tip side is injected. The collar portion is interposed between the upper mold and the lower mold to close the mold, and then the receiving surface portion is formed on the design surface side, and the lower edge portion of the collar portion on the design surface side related to the surface pad is formed. in the state in which the outer flange portion as a starting point here from the lower edge joint portions in contact is extending, a surface layer pad inner surface opposite to the design surface side is integrally joined to the surface of the core pad foam molding, A method for manufacturing a vehicle seat pad, which comprises removing the outer flange portion along the lower edge portion joint portion from the seat pad having the outer flange portion after demolding.
Here, the "bead foam molded article" referred to in the present invention is obtained by the so-called bead foaming method (Patent No. 4855138, JP 2015-101620, JP 2013-22911, JP 2011-105879, etc.). This is a foam molded product obtained by pre-foam molding beads impregnated with a foaming agent in pellets and then performing in-mold foam molding. The bead foaming method is also simply referred to as the bead method.
The method for manufacturing a vehicle seat pad according to claim 2 is the method of claim 1 , wherein a wedge is provided on the upper die and / or the lower die, and the outer flange portion is interposed between the upper die and the lower die. As the mold is closed, the wedge forms a V notch along the lower edge portion joint, and after demolding, the outer collar portion is removed from the seat pad having the outer collar portion according to the V notch. It is characterized by going . The method for manufacturing a vehicle seat pad according to claim 3 is characterized in that, according to claim 1 or 2, the bead foam molded product is a molded product containing at least one of foamed polypropylene, expanded polystyrene, or one of them. The method for manufacturing a vehicle seat pad according to the fourth aspect of the present invention is the method of manufacturing the vehicle seat pad according to the first to third aspects, wherein the core pad is located at a portion of the collar portion on the proximal end side of the outer collar portion of the core pad. A through hole penetrating from the front surface side to the back surface side of the core pad is provided, and after the mold is closed, the receiving surface portion is formed on the design surface side, and a flexible polyurethane foam molded portion that fills the inside of the through hole is formed. A surface pad having an inner surface opposite to the design surface side joined and integrated with the surface of the core pad is foam-molded.

In the method for manufacturing a vehicle seat pad of the present invention, an outer flange portion is interposed between the upper mold and the lower mold to close the mold, and then the surface pad is foam-molded. As a result, the foamed raw material cannot wrap around to the back surface side by integrally molding the surface layer pad with the core pad, and the back surface side of the mold is not soiled. Since the foamed raw material does not wrap around to the back surface side of the mold, the foamed raw material does not enter the groove for attaching the skin, and the deburring work is eliminated. Further, since the outer flange portion is interposed between the upper mold and the lower mold to close the mold, the outer flange portion itself acts as a sealing material, and the work of removing burrs on the parting line due to urethane leakage does not occur. Moreover, the outer flange that contributes to such quality improvement and workability improvement can be easily removed according to the perforations or V-notches provided along the lower edge joint, so that it does not take time and effort, and the seat pad can be removed. It exerts excellent effects such as no hindrance to the appearance shape.

It is one form of the manufacturing method of the seat pad of this invention, and is the perspective view of the seat pad with the outer flange, and the perspective view of the seat pad which removed the outer flange portion from here. It is a perspective view of the core pad seen from the back side. It is a perspective view of the core pad of another aspect alternative to FIG. It is sectional drawing which sets the core pad in the upper mold in the mold open state. It is sectional drawing which injects the foaming raw material into the lower mold in an open state. It is a cross-sectional view with a mold closed. It is a cross section of a surface pad integrated with a core pad formed by foam molding. It is a partial cross-sectional view which foam-molded the surface layer pad integrated with the core pad of another aspect. It is a partial cross-sectional view which foam-molded the surface layer pad integrated with the core pad of FIG. It is the perspective view of the seat pad with the outer flange of FIG. 9 which was demolded, and the perspective view of the seat pad which removed the outer flange portion from here. It is sectional drawing which opens the foam molding mold provided with the wedge of another aspect, and injects a foaming raw material. It is sectional drawing which closed the mold after FIG.

Hereinafter, a method for manufacturing a vehicle seat pad (hereinafter, also simply referred to as “seat pad”) according to the present invention will be described in detail. 1 to 12 are aspects of the present invention, FIG. 1 is a perspective view of a seat pad with an outer flange and a perspective view of the seat pad, FIG. 2 is a perspective view of a core pad viewed from the back surface side, and FIG. 3 is FIG. FIG. 4 is a cross-sectional view in which the core pad is set in the upper mold in the mold open state, FIG. 5 is a cross-sectional view in which the foamed raw material is injected into the lower mold in the mold open state, and FIG. A closed sectional view, FIG. 7 is a sectional view obtained by foam-molding a surface pad integrated with the core pad, FIG. 8 is a partial sectional view obtained by foam-molding a surface pad integrated with the core pad of another aspect, and FIG. 9 is FIG. A partial cross-sectional view of a surface pad integrated with a core pad formed by foaming, FIG. 10 is a perspective view of a demolded seat pad with an outer flange and a perspective view of the seat pad, and FIG. 11 is a foam having a wedge of another aspect. A cross-sectional view in which the foaming raw material is injected with the molding die in the open state, FIG. 12 shows a cross-sectional view in which the mold is closed after FIG.
In each drawing, the flange portion 22, the outer flange portion 23, the perforation 27, and the wedge 88 of the main part of the invention are highlighted in order to make the drawing easy to understand, and the parts not directly related to the present invention are omitted. The core pads 2 other than those shown in FIGS. 2 and 3 omit the hatching of the cross-sectional display.

In the method of manufacturing a vehicle seat pad, at least the receiving surface portion 41 on the side where the occupant comes into contact is formed of a flexible polyurethane foam molded product, and the surface pad 4 of the flexible polyurethane foam molded product is foam-molded so that the inner surface 4b side is lightweight. This is a manufacturing method in which the core pad 2 is joined and integrated (FIG. 7). The seat pad P is used for a seat or a backrest of a vehicle seat. Here, it is applied to the cushion pad P for the seat portion of the rear seat of the vehicle shown in FIG. In the cushion pad P in the vehicle installed state of FIG. 1, the diagonally upper right side of the paper surface is the front side of the vehicle, the diagonally lower left side is the rear part of the vehicle, the upper part of the paper surface is the upper side, and the lower side of the paper surface is the lower side. The upper and lower parts of the present invention follow this.
Prior to foam molding of the surface pad 4, the core pad 2 and the foam molding mold 7 are prepared.

The core pad 2 is a core member having a flange portion 22 having an outer flange portion 23 at the tip thereof on its side wall 21 and integrated with the surface layer pad 4 by covering the surface 2a side by foam molding of the surface layer pad 4. Yes (Figs. 2 and 7). The lower half of the cushion pad P is formed, and the flange portion 22 protruding outward at the lower portion of the side wall 21 is the core pad 2 having the outer flange portion 23 at the tip portion. As shown in FIG. 2, the core pad 2 of the present embodiment is formed so that the collar portion 22 and the outer collar portion 23 surround the side wall 21 of the core pad 2. In the flange portion 22 that goes around the side wall 21 of the core pad 2 and extends outward from the side wall 21, the outer flange portion 23 is joined to the lower edge portion 42a on the design surface side of the surface layer pad 4. Starting from the part 221 and extending from here to the outside horizontally as shown in FIG. Then, the perforation 27 is provided at the root portion of the outer collar portion 23 with the collar portion 22 at a substantially intermediate point in the width direction. The perforations 27 are formed in a curved dot shape so as to circulate and surround the side wall 21 at the edge of the lower edge portion joint portion 221. The outer flange portion 23 is easily separated from the main body of the core pad 2 along the perforation 27.
Here, the "front side" of the core pad 2 is the back side of the paper surface in FIG. 2, and is the "front side" of the cushion pad P of FIG. 1 mounted on the vehicle. The "design surface side" of the surface layer pad 4 is also the "front surface side" of the paper surface in terms of the cushion pad P of FIG. 1 attached to the vehicle, and has the same meaning. The wording is used properly to make it easier to identify the part.

The core pad 2 is a bead foam molded product having an apparent density smaller than that of the flexible polyurethane foam molded product. The core pad 2 is a lumpy bead foam molded product. It is a core member composed of a bead foam molded body having an apparent density smaller than the apparent density of the flexible polyurethane foam molded body forming the surface pad 4, and is arranged on the back surface side of the cushion pad. The density of the core pad 2 and the surface pad 4 is compared not by the density of the material before foaming but by the apparent density after foaming.
The bead foam molded product of the core pad 2 is sufficient if the apparent density is smaller than the apparent density of the flexible polyurethane foam molded product forming the surface pad 4, but at least one of non-breathable expanded polypropylene, expanded polystyrene, or one of them is satisfied. It is more preferable that the molded product contains. For example, the styrofoam molded product of the bead method styrofoam is a beaded styrofoam molded product in which air bubbles are sealed inside, and most of the volume is made lightweight by gas, and the apparent density is the appearance of the flexible polyurethane foam molded product. Can be less than density. Foamed polypropylene of bead method expanded polypropylene is also very similar to expanded polystyrene, and can be made into a beaded expanded molded product in which air bubbles are sealed inside, which is functionally excellent as a material for the core pad 2 and can reduce its apparent density. Foamed polypropylene is also used for the core pad 2 of the present embodiment. Foamed polypropylene is more elastic than Styrofoam, and by foam molding of the surface layer pad 4, the outer flange portion 23 can exert a sealing function as a gasket, and as a constituent material of the core pad 2 for seat pad P, which is required to have cushioning properties. It has become preferable.

The core pad 2 is preferably provided with a through hole 24 penetrating from the front surface 2a side to the back surface 2b side near the outer peripheral edge of the core pad 2 as shown in FIG. 8, and further, the core pad of the through hole 24 is provided as shown in FIG. It is more preferable to increase the hole diameter of the back surface 2b side portion of No. 2 to provide a recess 241 having a large hole diameter. This is because the joint integration of the surface pad 4 and the core pad 2 is strengthened (details will be described later). Reference numeral 29 indicates a groove for attaching the skin.

The foam molding mold 7 is a split mold as shown in FIG. 5, and the lower mold 8 and the upper mold 9 are connected so as to be openable and closable. When the mold is closed as shown in FIG. 6, the lower cavity surface 81, which is dented like a bowl to form the design surface of the receiving surface portion 41, and the upper cavity surface 91, which is aligned with the back surface 2b of the core pad 2 which is flat as a whole. Then, the cavity C of the cushion pad P is made. The foam molding mold 7 is such that the outer flange portion 23 is interposed between the upper mold 9 and the lower mold 8 to close the mold. As the mold is closed, the outer flange surface 23a abuts on the lower mold surface 89, and the outer flange back surface 23b abuts on the upper mold surface 99, so that the lower mold surface 89 and the upper mold surface 99 come into contact with each other. The outer collar portion 23 is sandwiched over the entire circumference.
The foam molding molds 7 of FIGS. 4 to 9 have a mold structure in which the surface pad 4 integrated with the core pad 2 which is the cushion pad is formed in an upside down position with the cushion pad of FIG. 1 in the vehicle installed state. It has become.

Using the foam molding mold 7 and the core pad 2, the seat pad P is manufactured as follows, for example.
First, the foam molding mold 7 is set to the mold open state shown in FIG. Under this mold open state, the core pad 2 is set in the upper mold 9. The outer flange portion 23 related to the flange portion 22 of the core pad 2 is applied to the upper mold surface 99, and the remaining flange portion 22 on the base end side and the back surface 2b of the core pad are brought into contact with the upper mold cavity surface 91 to set. To do.

Next, the foaming raw material g is injected into the lower mold cavity surface 81, and the outer flange portion 23 on the tip end side of the flange portion 22 is interposed between the upper mold 9 and the lower mold 8 to close the mold.
A predetermined amount of the foaming raw material g for the surface pad 4 (raw material for the flexible polyurethane foam molded product) is injected onto the lower mold surface 89 dented in a bowl shape using an injection nozzle NL or the like (FIG. 5). Subsequently, the upper mold 9 is operated to close the mold (FIG. 6). The outer flange portion 23 is interposed between the upper mold 9 and the lower mold 8 so that the outer flange portion 23 abuts on the lower mold surface 89, and the mold is closed. As described above, the flange portion 22 and the outer flange portion 23 are formed so as to circulate and surround the side wall 21 of the core pad 2, and the outer side 21 circulates between the upper mold 9 and the lower mold 8. The collar portion 23 is interposed over the entire circumference thereof. The upper mold 9 and the lower mold 8 securely sandwich both plate surfaces of the plate-shaped outer flange portion 23 and seal the plates. By closing the upper mold 9 and the lower mold 8, a cushion pad cavity C in which the core pad 2 is insert-set is formed. In this embodiment, the mold is closed after the foaming raw material g is injected, but the foaming raw material g can be injected after the mold is closed.

After closing the mold, the main process is foam molding. A surface pad 4 made of a flexible polyurethane foam molded product having a seated occupant receiving surface portion 41 (here, a “seat surface portion”) on the design surface 4a side is foam-molded. The receiving surface portion 41 is formed on the design surface 4a side, and the inner surface 4b side is joined and integrated with the surface 2a of the core pad 2 while the outer flange portion 23 is sandwiched and sealed between the lower mold surface 89 and the upper mold surface 99. The surface pad 4 is foam-molded. Thus, in the foam molding process, the foamed raw material g on the lower mold cavity surface 81 side does not get over the sandwiched and sealed outer flange portion 23 and enter the upper mold cavity surface 91 side.
The mold closed state is maintained for a predetermined time to form the receiving surface portion 41 of the surface layer pad 4, the lower edge portion 42 of the surface layer pad 4 reaches the flange portion 22 in the cavity C, and the side wall 21 is covered by the pad side surface 43. cover. Then, the outer flange portion 23 is exposed outward from the lower edge portion joint portion 221 in contact with the lower edge portion 42a on the design surface side related to the surface layer pad 4, and the inner surface 4b opposite to the design surface 4a side is exposed. The surface pad 4 whose side is joined and integrated with the surface 2a of the core pad 2 is foam-molded (FIG. 7).

Here, if the core pad 2 is provided with a through hole 24 penetrating from the core pad front surface 2a side to the back surface 2b side (FIG. 8), the foamed raw material g comes into contact with the occupant in foam molding after the mold is closed. In the process of ascending so as to fill the surface pad main body cavity C having the receiving surface portion 41 on the side, it advances into the through hole 24. In the foam molding process of the surface pad 4, the receiving surface portion 41 is formed and the flexible polyurethane foam molded portion 44 that fills the inside of the through hole 24 is formed, and the inner surface 4b side is joined and integrated with the surface 2a of the core pad 2. The pad 4 is foam-molded. Further, when the back surface side through hole 24 is expanded in diameter to provide the recess 241 (FIG. 9), the inside of the through hole 24 and the recess 241 is filled to form a flexible polyurethane foam molded portion 441, which is further joined to the core pad 2. A surface pad 4 of a reinforced flexible polyurethane foam molded product is produced.

When the foam molding of the surface layer pad 4 is completed and the mold is removed, a cushion pad P having an outer flange portion 23 in which the core pad 2 and the surface layer pad 4 are integrated can be obtained (FIG. 1). The cushion pad P having the outer flange portion 23 has a core pad 2 embedded and integrated into a foam-molded surface pad 4, and the outer flange portion 23 is provided so that burrs do not appear on the back surface 2b of the core pad.
However, even if the skin is covered as it is to make a seat cushion, the outer collar portion 23 protruding from the side wall 21 interferes.
Therefore, in the present invention, the outer collar portion 23 that has finished its role is simply removed from the seat pad P having the outer collar portion 23 (FIG. 1). As described above, the core pad 2 is provided with a perforation 27 at the base of the outer collar portion 23 in advance. After demolding, the outer flange portion 23 is removed from the seat pad P having the outer flange portion 23 according to the perforation 27 provided along the lower edge portion joint portion 221. By cutting the outer collar portion 23 at the perforation 27 from the seat pad P having the outer flange portion 23 shown in the lower part of FIG. 1, the desired seat pad P shown in the upper part of the figure is completed.
Reference numeral 211 is an inner edge portion of the side wall, reference numeral 25 is a base portion for forming a seat portion, reference numeral 26 is a raised portion for a mating portion with a backrest, reference numeral 4A is a main portion, reference numeral 4B is a side portion, reference numeral 4D is a slope, and reference numeral 4E is a back portion. The mating portion with the rest, reference numeral 43f is the side surface of the pad on the front side of the vehicle, reference numeral 43r is the side surface of the pad on the rear side of the vehicle, reference numeral 49 is a suspension groove, reference numeral 491 is a vertical groove, reference numeral 492 is a horizontal groove, and reference numeral 84 is a raised portion for a suspension groove. Is shown.

10 to 12 show another aspect and another aspect of the method for manufacturing the seat pad. FIG. 10 shows a seat pad and a seat pad with an outer flange corresponding to FIG. 1, and a seat pad having an outer flange portion 23 using the core pad 2 of FIG. 3 as in the case of using the core pad 2 of FIG. P is manufactured, and then the outer flange portion 23 is removed to obtain a seat pad P. Instead of the perforation 27 in FIG. 2, a V notch 28 as shown in FIG. 3 is provided. The V notch 28 is formed in a line shape so as to circulate and surround the side wall 21 at the edge of the lower edge portion joint portion 221. The outer flange portion 23 is easily separated from the core pad 2 along the V notch 28. Although the V notch 28 is provided on the outer collar portion surface 23a, it may be provided on the outer flange portion back surface 23b or both.

Further, another method of manufacturing the seat pad P as shown in FIGS. 11 and 12 can be adopted. Here, the core pad 2 having no perforations 27 or V notch 28 as shown in FIGS. 2 and 3 is set in the upper mold 9 as it is, and the V notch 28 is formed by closing the mold thereafter. The V notch 28 is formed by the wedge 88 provided on the upper mold 9 or the lower mold 8 as the outer flange portion 23 is interposed between the upper mold 9 and the lower mold 8 to close the mold. As shown in FIG. 11, a wedge 88 for forming a V notch is provided on the lower mold surface 89. As the mold is closed, the wedge 88 bites into the flange portion 22 of the core pad 2 set in the upper mold 9 as shown in FIG. 12 to form a V notch 28. Similar to FIG. 3, the V notch 28 is formed around the lower edge portion joint portion 221 in a curved groove shape so as to surround the side wall 21.
Although the wedge 88 for forming the V notch is provided on the lower mold surface 89, it may be provided on the upper mold surface 99 or on both sides.
Other configurations are the same as those of the present embodiment described in FIGS. 4 to 9, and after demolding, from the seat pad P having the outer flange portion 23, according to the V notch 28 provided along the lower edge portion joint portion 221. The outer flange portion 23 is removed to obtain a desired seat pad P.

(3) Effect The method for manufacturing a vehicle seat pad configured in this manner includes beads having a core pad 2 and a surface layer pad 4, and the core pad 2 has an apparent density lower than the apparent density of a flexible polyurethane foam molded product. Since it is formed of a foam molded body, the weight is reduced. Nevertheless, since the receiving surface portion 41 with the seated occupant is provided on the design surface 4a side of the surface layer pad 4 made of the flexible polyurethane foam molded body, comfort such as cushioning is ensured.
Further, instead of simply stacking the surface pad 4 and the core pad 2 to form the seat pad P, the core pad 2 is embedded and integrated by the foam molding forming the surface pad 4, so that the overlapping surface is used by the occupant. It does not cause a situation in which abnormal noise is generated due to misalignment.

Then, the outer flange portion 23 provided on the side wall 21 of the core pad 2 is brought into contact with the lower mold surface 89, and the outer flange portion 23 is interposed between the upper mold 9 and the lower mold 8 to close the mold. In the subsequent foam molding of the surface pad 4, the foam raw material g does not wrap around to the back surface 2b side of the core pad. When the outer flange portion 23 is formed so as to circulate and surround the side wall 21 of the core pad 2, the lower mold surface 89 and the upper mold surface 99 cover the outer flange portion 23 over the entire circumference thereof. Since the surface layer pad 4 can be formed with the outer flange portion 23 exposed to the outside of the cavity C by sandwiching and sealing, the foamed raw material g in the cavity C is blocked by the sandwiching and sealing area and reaches the core pad back surface 2b. I never end up. Even if the groove 29 for attaching the skin is provided along the outer periphery of the back surface 2b of the core pad, the foaming raw material g does not enter the groove 29. Therefore, after molding the surface pad 4, it is not necessary to remove the cured product of the foamed raw material g that has entered the groove 29.

Further, if the outer collar portion 23, which does not stain the back surface 2b side of the core pad and is useful for eliminating the deburring work of the skin mounting groove 29, is left as it is, it is convenient when covering the seat pad P with the skin. Although it is bad, the outer collar portion 23 can be easily separated, so that there is no problem. Since the core pad 2 is provided with a perforation 27 or a V notch 28 in advance along the lower edge portion joint portion 221, the outer flange portion 23 is formed along the perforation 27 or the V notch 28 after foam molding of the surface layer pad 4. It can be easily removed from the seat pad P. Regarding the V notch 28, a wedge 88 for forming a V notch is provided in the foam molding mold 7 so that the V notch 28 is formed by closing the mold even if the core pad 2 is not in the stage of setting the foam molding mold 7. You may. In such a case, the manufacturing cost of the core pad 2 can be reduced, which is more preferable.

Further, when the outer flange portion 23 is formed at the tip portion of the plate-shaped flange portion 22 that surrounds the side wall 21 of the core pad 2 and projects horizontally outward, when the foam molding of the surface layer pad 4 is closed, the outer flange portion 23 is formed. The sandwiching seal of the outer flange portion 23 by the lower mold surface 89 and the upper mold surface 99 can be smoothly and surely performed. Since the outer collar portion 23 is formed as a part of the bead foam molded body of the core pad 2 and is non-breathable unlike the open cell type, it is foamed at the time of foam molding by sandwiching the mold surface of the foam molding mold 7. Prevents the raw material g from leaking out of the mold. Further, the outer flange portion 23 is a part of the foam molded body and has appropriate elasticity, and a gasket is used when the outer flange portion 23 is sandwiched and sealed between the lower mold surface 89 and the upper mold surface 99. Even if it is not provided, it can be sealed only by the outer flange portion 23. By providing the outer flange portion 23 on the core pad 2 made of the bead foam molded body, it can be easily sealed only by sandwiching the outer flange portion 23 when molding the surface layer pad 4, and the foam raw material g is moved to the back surface 2b side of the core pad. It has a very reasonable structure to prevent leakage.

Moreover, when the mold is closed, the outer flange portion 23 is interposed between the lower mold 8 and the upper mold 9, and the lower mold surface 89 and the upper mold surface 99 do not come into contact with each other. Therefore, the surface pad 4 is foam-molded. , The parting line traces of the mold dividing line seen on the outer surface of the cushion pad P do not occur. When the mold is closed, the mold surfaces do not come into contact with each other, there is no parting line, and burrs do not naturally appear.
Even if the deburring work is not performed, the portion of the outer flange portion 23 of the seat pad P after the foam molding of the surface layer pad 4 is exposed. The seat pad P can be commercialized without deburring work, which contributes to cost reduction and workability improvement.

Furthermore, by providing the through hole 24, the soft polyurethane foam molded portion 44 filled in the through hole 24 of the core pad 2 exerts an anchor effect by foam molding of the surface layer pad 4, and the surface layer pad 4 and the bead foam are formed. The integration with the core pad 2 which is a molded body can be strengthened. When a recess 241 having a large hole diameter on the back surface side of the through hole 24 is provided, the flexible polyurethane foam molded portion 441 filled in the recess 241 serves as a stopper, and the surface layer pad 4 and the core pad 2 are more reliably integrated. Can be made into something.
As described above, the method for manufacturing the seat pad for the present vehicle exerts the various excellent effects described above and is extremely useful.

In the present invention, the present invention is not limited to the one shown in the above embodiment, and various modifications can be made within the scope of the present invention according to the purpose and application. The shape, size, number, material, etc. of the core pad 2, flange portion 22, outer flange portion 23, through hole 24, recess 241, surface pad 4, flexible polyurethane foam molded part 44,441, foam molded mold 7, etc. are used. It can be selected as appropriate according to. Although the cushion pad P for the seat is used in the embodiment, it can also be applied to the back pad for the backrest. Further, the core pad 2 is not limited to the bead foam molded product made of expanded polypropylene and expanded polystyrene, and may be, for example, a bead foam molded product made of expanded polyethylene.

2 core pad 2a surface (surface of core pad)
21 Side wall 22 Brim part 221 Lower edge joint part 23 Outer collar part 24 Through hole 27 Perforation 28 V notch 4 Surface pad 4a Design surface (design surface of surface pad)
4b Inner surface (inner surface of surface pad)
41 Receiving surface part 42 Lower edge part (lower edge part of surface pad)
42a Lower edge part on the design surface side related to the surface pad 44 Soft polyurethane foam molded part 8 Lower type 88 Wedge 9 Upper type P seat pad (cushion pad)
g Foaming material

Claims (4)

In a method for manufacturing a vehicle seat pad in which at least the receiving surface portion on the side where the occupant comes into contact is formed of a surface pad of a flexible polyurethane foam molded product.
A core pad, which is a bead foam molded product and has a flange portion protruding outward from the side wall, is set in the upper mold, and then a foaming raw material is injected into the lower mold cavity surface, and the tip side of the collar portion is used. The outer collar is placed between the upper and lower molds to close the mold,
Subsequently, the receiving surface portion is formed on the design surface side, and the outer collar portion starts from the lower edge portion joint portion in contact with the lower edge portion on the design surface side of the collar portion related to the surface layer pad. in a state extending, a surface layer pad inner surface opposite to the design surface side is integrally joined to the surface of the core pad foam molding,
A method for manufacturing a vehicle seat pad, which comprises removing the outer collar portion along the lower edge portion joint from the seat pad having the outer flange portion after demolding. A wedge is provided on the upper mold and / and the lower mold, and the wedge is placed along the lower edge portion joint as the outer flange portion is interposed between the upper mold and the lower mold to close the mold. Form a V notch,
The method for manufacturing a vehicle seat pad according to claim 1, wherein after the mold is removed, the outer collar portion is removed from the seat pad having the outer collar portion according to the V notch. The method for manufacturing a vehicle seat pad according to claim 1 or 2, wherein the bead foam molded product is a molded product containing at least one of foamed polypropylene, expanded polystyrene, or one of them. A through hole penetrating from the front surface side to the back surface side of the core pad is provided in the portion of the collar portion on the base end side of the outer collar portion of the core pad, and after the mold is closed, the core pad is provided with a through hole. A surface pad in which the receiving surface portion is formed on the design surface side and a flexible polyurethane foam molded portion that fills the inside of the through hole is formed, and the inner surface side opposite to the design surface side is joined and integrated with the surface of the core pad. The method for manufacturing a vehicle seat pad according to any one of claims 1 to 3, wherein the foam molding is performed.

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