JP7377606B2 - Vehicle cushion pad and its manufacturing method - Google Patents

Description

The present invention relates to a vehicle cushion pad constituting a vehicle seat and a method for manufacturing the same.

Cushion pads that make up the seats of automobiles and other vehicles have traditionally been made of soft polyurethane foam moldings to provide comfortable cushioning, but in recent years, the interior of the back side has been There is a growing movement to replace foamed resin particles with foamed molded products (hereinafter also referred to as "foamed resin molded products"). However, a shaft-shaped frame is usually attached to the cushion pad along the outer periphery in plan view for reinforcement or the like. A part of the frame protrudes and also serves as an attachment point to the vehicle body.
One manufacturing method is to integrate the frame into a foamed resin molded body by insert molding and then manufacture a cushion pad. However, with this manufacturing method, molding shrinkage of the foamed resin molding applies large stress to the frame, causing warping and twisting. The predetermined accuracy cannot be obtained, making it difficult to subsequently mold the cushion pad or to attach it to the vehicle body.
For this reason, several inventions have been proposed to improve accuracy (for example, Patent Documents 1 and 2).

JP2018-139820A JP2018-23634A

However, Patent Documents 1 and 2 are limited to methods of manufacturing a foamed resin molded body by insert molding after setting a frame in a mold. Even if a slit or void forming process is provided, as long as a part of the frame is embedded in the foamed resin molded product (the core pad of the present invention) and integrated, the foamed resin molded product will shrink after demolding. The frame of a foamed resin molded article with a frame is affected to some extent by the shrinkage. It is considered that it is difficult to stably obtain a predetermined accuracy. Even if the frame is within the tolerance of the product dimensions, when it comes to a foamed resin molded product with a frame, not only the foamed resin molded product itself but also the frame may warp or twist due to molding shrinkage of the foamed resin molded product. There is a risk that the product may be deformed and may not fit within the dimensional tolerance.

The present invention solves the above problems, and provides a cushion pad for a vehicle and a method for manufacturing the same, which contributes to improving quality and yield by ensuring that a frame is accurately and stably arranged in a finished product. The purpose is to

In order to achieve the above object, the gist of the invention as set forth in claim 1 is to provide a cushion pad for a vehicle in which at least the contact surface portion on the side abutted by a seated occupant is formed of a soft polyurethane foam molded product. A core pad which is a molded body and has a groove in its top surface and a through hole penetrating from the bottom surface of the groove to the back surface opposite to the top surface, and which is separate from the core pad. a shaft-shaped frame that enters the groove and is placed on the core pad; and a soft polyurethane foam molded body, which has the contact surface portion and whose inner surface on the opposite side contacts the top surface. A cushion pad for a vehicle, comprising: a surface layer pad which is brought into contact with each other to form a seat layer, and is foam-molded to form a groove filling part that fills the inside of the frame-filled groove. It is in. The cushion pad for a vehicle according to the second aspect of the present invention is characterized in that the groove width of the groove is larger than the shaft diameter of the frame. A vehicle cushion pad according to claim 3 is the invention according to claim 1 or 2, wherein a plurality of through holes are provided, and the cross-sectional shape of the through holes gradually increases from the back surface of the core pad toward the bottom surface of the groove. It is characterized by being set small. In the vehicle cushion pad according to claim 4, in the first to third aspects, the through hole has a large diameter portion larger than the hole diameter at the bottom surface of the groove, and the soft polyurethane foam molded product is arranged in the recess. It is characterized by having an intrusion hardened part that penetrates into the large diameter part from the groove.
The gist of the invention as set forth in claim 5 is a method for manufacturing a cushion pad for a vehicle in which at least the contact surface portion on the side that a seated occupant contacts is formed of a soft polyurethane foam molded product, the cushion pad being made of a foamed molded product of expandable resin particles. Insert the protrusion protruding from the upper mold cavity surface into the back side hole opening of the through hole that penetrates from the bottom of the groove provided on the top surface of the core pad to the back surface of the core pad, and set the core pad in the upper mold. At the same time, the axial frame placed in the groove is magnetically attracted to the magnet fixed to the tip of the protrusion, and the frame is set in the groove, and then a soft polyurethane foam molded article is placed on the lower mold cavity surface. Injecting the foaming raw material and closing the mold, then forming a seat layer having the abutting surface portion on the lower mold cavity surface and bringing the inner surface on the opposite side into contact with the top surface of the core pad, A method of manufacturing a cushion pad for a vehicle, characterized in that a surface pad of a soft polyurethane foam molded product having a groove filling portion filled in the groove filled in the frame is formed by foam molding. A sixth aspect of the present invention provides a method for manufacturing a cushion pad for a vehicle according to the fifth aspect, wherein the width of the groove is larger than the shaft diameter of the frame. According to a seventh aspect of the invention, there is provided a method of manufacturing a vehicle cushion pad according to the fifth or sixth aspect, wherein a plurality of through holes are provided, and the cross-sectional shape of the through holes is adjusted from the back surface of the core pad toward the bottom surface of the groove. is gradually set smaller, the protrusion is tapered toward the tip in accordance with the cross-sectional shape, and the protrusion is inserted into the hole on the back side of the through hole, thereby attaching the core pad to the upper mold. It is characterized by being set. The invention according to claim 8 provides a method for manufacturing a cushion pad for a vehicle, in which, in claims 5 to 7, when the projection is inserted into the through hole, the hole wall of the back side opening of the through hole is provided. It is characterized in that an engaging part is provided that bites into the core pad, and the core pad is held on the upper die by the engaging part. The method for manufacturing a vehicle cushion pad according to claim 9 is the method according to claims 5 to 8, wherein the through hole has a large diameter portion larger than the hole diameter at the bottom surface of the groove, and The foaming raw material is characterized in that during foam molding of the surface layer pad, the foaming material enters the large diameter portion from the groove to form an intrusion hardening portion.

As in claims 1 and 5, when the frame is disposed separately from the core pad having a groove on the top surface and inserted into the groove, the frame is not affected by molding shrinkage of the core pad. If the core pad is provided with a through hole that penetrates from the bottom surface of the groove to the back surface opposite to the top surface, when the core pad is set on the upper mold, a protrusion is provided at a position opposite to the through hole and the By fixing a magnet to the tip, the core pad and frame can be easily set on the upper mold by inserting a protrusion into the through hole and magnetically attracting the frame with the magnet. After that, the mold is closed and the surface pad is foam-molded to produce a cushion pad. The frame can provide flexibility in the arrangement set within the groove, and since the surface pad having the groove filling part and the seat layer that fills the frame-filled groove is foam-molded, the frame can be arranged in the groove. To obtain a cushion pad buried while maintaining dimensional accuracy.

The vehicle cushion pad and its manufacturing method of the present invention can maintain the dimensional accuracy of a pre-formed frame in its initial state, even if the cushion pad incorporates a core pad made of a foam molded product of expandable resin particles. It allows for stable production and is highly effective in improving quality and yield.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall perspective view of a cushion pad, which is an embodiment of a vehicle cushion pad and a method for manufacturing the same according to the present invention. FIG. 2 is a perspective view of the inner lower part of the cushion pad with the surface pad of FIG. 1 removed. It is a sectional view taken along the line III-III in FIG. 1, and the upper view is an enlarged view inside the circle. FIG. 3 is an exploded perspective view of the inner lower part of the cushion pad in FIG. 2; FIG. 3 is a perspective view of the core pad seen from the back side. (A) is an explanatory sectional view showing how to set the core pad on the upper mold, and (B) is a sectional view taken along the line VI-VI of (A). It is a partially enlarged cross-sectional view of the core pad and frame set on the upper mold. FIG. 3 is an explanatory cross-sectional view of injecting foaming raw material after setting the frame-containing core pad into the upper mold. It is an explanatory cross-sectional view with the mold closed. FIG. 2 is an explanatory cross-sectional view of a surface layer pad formed by foam molding. FIG. 3 is a diagram showing another aspect of the core pad in place of FIG. 2; FIG. 6 is a diagram showing another aspect of the core pad in place of FIG. 5; 13 is a diagram showing another aspect of the core pad shown in FIG. 12 in place of FIG. 6, in which the core pad is set on an upper mold; FIG. (A) is an alternative view of FIG. 7 in which the core pad and frame of FIG. 12 are set on the upper mold, (B) is an enlarged view of the area around the protrusion, and (C) is a sectional view taken along the Y-Y line of (A).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The vehicle cushion pad (hereinafter also simply referred to as "cushion pad") and its manufacturing method according to the present invention will be described in detail below.
1 to 14 show one embodiment of the cushion pad and its manufacturing method of the present invention, FIG. 1 is a perspective view of the cushion pad, FIG. 2 is a perspective view of the inner lower part of the cushion pad with the surface pad removed, and FIG. 3 is a perspective view of the cushion pad. FIG. 1 is a cross-sectional view taken along the line III-III in FIG. 1, FIG. 4 is an exploded perspective view of the inner lower part of the cushion pad, FIG. 5 is a perspective view of the core pad from the back side, and FIG. 6 is a cross-sectional view of setting the core pad on the upper mold. 7 is a cross-sectional view of the core pad and frame set in the upper mold, FIG. 8 is a cross-sectional view of the foaming material being injected after the core pad with frame is set in the upper mold, FIG. 9 is a cross-sectional view of the mold closed, and FIG. 11 is a cross-sectional view of a surface pad formed by foam molding, FIG. 11 is a diagram of another embodiment in place of FIG. 2, FIG. 12 is a diagram of another embodiment in place of FIG. 5, and FIGS. 13 and 14 are diagrams of another embodiment in place of FIGS. 6 and 7. In each figure, important parts of the invention are emphasized and parts not directly related to the invention are simplified or omitted to make the drawings easier to understand.

(1) Vehicle Cushion Pad The vehicle cushion pad 1 is a cushion pad that supports the lower body of a seated occupant. Applicable to the cushion pad 1 of the rear seat of a vehicle (Figures 1 to 5). If the cushion pad 1 is covered with an outer skin to form a seat cushion, a rear seat with an auxiliary seat portion 3C in the vehicle width direction is formed with a seat back made by covering a known back pad with an outer skin. FIG. 3 shows the cushion pad 1 installed in a vehicle, with the left side of the page showing the front of the vehicle and the top of the page showing the top of the vehicle.
The cushion pad 1 includes a core pad 2, a frame 4, and a surface pad 3.

The core pad 2 is a foamed molded body of foamable resin particles formed into a block shape and has a size that occupies the inner lower part of the cushion pad 1 (FIGS. 3 and 5). Expandable resin particles are resin particles in which a volatile expansion agent is encapsulated in hollow particles whose capsule walls are made of thermoplastic resin such as polystyrene or polypropylene, and expand upon heating. The "foamed molded product of expandable resin particles" of the present invention refers to a foamed resin molded product that is foam-molded by injecting a large number of expandable resin particles into a mold. For example, it is a foam molded product obtained by a so-called bead foaming method, and is a block-shaped foam molded product that is formed by in-mold foam molding after preliminary foam molding of raw material beads. The bead foaming method is also simply referred to as the bead method. The bead foam molded product is preferably a molded product containing foamed polystyrene, foamed polypropylene, foamed polyethylene, or at least one of these. It is a bead foam molded product with air bubbles sealed inside, and most of the volume is gas, making it lightweight and retaining its shape.

An annular groove 22 as shown in FIG. 4 is formed along the outer peripheral edge 21 of the top surface 2a of the core pad 2, which is on the top side when installed in a vehicle. An annular groove 22 that is one size smaller than the outer circumferential shape of the top surface 2a in a plan view runs a U-shaped cross section formed by recessing the top surface 2a. Although the groove 22 of this embodiment is a continuous annular groove in plan view as shown in FIG. 4, the frame 4 inserted into the groove 22 can be maintained in a desired shape during the manufacturing process of the cushion pad 1. If so, the grooves may be discontinuous (details will be described later).
The groove width W22 of the groove 22 is set to be larger than the shaft diameter t4 of the frame 4 so that the frame 4 can fit into the groove with a margin (FIG. 3). The depth of the groove 22 is also set larger than the shaft diameter t4 of the frame 4. In the present invention, "the frame is placed in the groove" does not necessarily mean that the entire frame 4 is placed in the groove 22. The frame 4 is housed in the annular groove 22, and a notch 23 is provided so that the U-shaped protrusion 42 protrudes horizontally outward even if the frame main portion 41 is housed in the groove 22. Here, cuts 23 having a U-shaped cross section that are approximately equal to the groove width W22 and depth of the groove 22 penetrate from four parts of the groove 22 on the rear side of the vehicle to the core pad side wall surface 27. . In this embodiment, the groove 22 has a substantially U-shaped cross section, but the groove 22 may have a dovetail groove shape, an inverted trapezoidal cross section, or the like.

The core pad 2 is provided with a through hole 26 that penetrates from the bottom surface 221 of the groove 22 to the back surface 2b opposite to the top surface 2a. It is preferable to provide a plurality of through holes 26 (three in this case) as shown in FIG. This is to ensure that the core pad 2 and frame 4 are held securely in the manufacturing method of the cushion pad 1, which will be described later. The through hole 26 may have the same cross-sectional shape as shown in FIG. 13, but it is more preferable that the cross-sectional shape S26 of the through hole 26 is set gradually smaller in the direction from the back surface 2b of the core pad 2 to the groove bottom surface 221 as shown in FIG. . This is because it becomes easier to insert the protrusion 92 (details will be described later) of the upper die 9 into the through hole 26. The through hole 26 of this embodiment has a circular cross-sectional shape S26, and the hole diameter gradually decreases from the core pad back surface 2b toward the groove bottom surface 221.

The core pad 2 shown in FIG. 5 can be divided into two (multiple divisions) as shown in other embodiments of FIGS. 12 and 13, for example. The two divided core pads 2A and 2B are each provided with two (plural) through holes 26 to facilitate positioning and setting of the core pad 2 to the upper mold 9.
Reference numeral 24 indicates a through hole penetrating from the top surface 2a to the back surface 2b of the core pad 2, reference numeral 25 indicates a recess with a larger hole diameter than the through hole 24 on the back surface 2b side of the core pad, and reference numeral 272 indicates a hole in the side wall surface 27 of the core pad 2. The provided stepped surface, reference numeral 275, indicates an outwardly inclined surface that is inclined outwardly toward the top surface 2a.

The frame 4 is a shaft-shaped body that is separate from the core pad 2 and inserted into the groove 22 and arranged in an annular or curved shape along the outer peripheral edge 21 of the core pad 2.
The frame 4 of this embodiment is made of an annular (ring-shaped) metal wire that is loosely fitted into an annular groove 22 formed along the outer peripheral edge 21 of the top surface 2a. The frame 4 is made of a ferromagnetic metal such as iron, nickel, cobalt, and alloys thereof, which is strongly attracted to the magnet, at least at a portion in contact with the magnet 93. The frame 4 is provided with a frame main part 41 that fits into the groove 22 by inserting the frame 4 into the groove 22, and a U-shaped protrusion 42 that projects from the notch 23 to the outside of the core pad 2. The frame 4 inserted into the groove 22 and placed there is loosely fitted into the groove 22, and the frame 4, which is pre-shaped into an annular shape, has the flexibility to maintain its shape and adjust its position. . Therefore, the wire that falls within the dimensional tolerance can be placed and set in the groove 22 while maintaining its dimensional quality.
Note that even a frame 4 in which a metal plate piece or the like is incorporated in a part is considered to be the shaft-shaped frame 4 of the present invention. Further, the cross section of the axial frame 4 is not limited to the circular shape shown in FIG. 3. It may be a polygon such as a rectangle or an ellipse.

The surface pad 3 is a cushion body in which at least a contact surface portion 311 on the side abutted by a seated occupant is formed of a soft polyurethane foam molding. The surface pad 3 has a contact surface portion 311, and the inner surface 3b on the opposite side thereof forms a seat layer 31 in contact with the top surface 2a of the core pad 2, and is foam-molded. A seated occupant contacts the contact surface portion 311 via a not-shown skin covering the cushion pad 1.

In the foam molding of the surface pad 3, even if its inner surface 3b is brought into contact with the core pad 2, the soft polyurethane foam molding of the surface pad 3 and the core pad 2, which is a foam molding of expandable resin particles, have poor adhesion. Therefore, the bond between the two becomes weak and unstable. However, in the present invention, during the foam molding process of the surface pad 3, the foaming raw material g for the soft polyurethane foam molded product of the surface pad 3 enters the groove 22 containing the frame 4, and the groove 22 is formed together with the frame 4. A groove filling portion 33 to be filled is formed. Therefore, the cushion pad 1 has a surface pad 3 formed integrally with the core pad 2 and the frame 4 by foam molding. If the concave groove 22 is formed into the above-mentioned dovetail groove shape, the surface pad 3 and the core pad 2 can be more firmly integrated with the frame 4 interposed therebetween. In addition, a large diameter portion larger than the hole diameter at the groove bottom surface 221 is formed in the through hole 26, and when the surface pad 3 is foam-molded, a part of the foaming raw material g enters the large diameter portion of the through hole 26 and enters the hardened portion. Even if 36 is formed, the surface pad 3 and core pad 2 with the frame 4 interposed therebetween will be more strongly integrated. FIG. 3 shows an intrusion hardening portion 36 extending from the groove filling portion 33 and filling the large diameter portion of the through hole 26. As shown in FIG.
Further, by molding the surface pad 3, a hole filling part 34 and a depression filling part 35 are formed to fill the through hole 24 and the depression 25, and the surface pad 3 becomes firmly integrated with the core pad 2 and the frame 4. In the side circumferential layer 32 of the surface pad 3, a lower portion 37 that fills the outside of the outer inclined surface 275 and a lower portion 37 that fills the outside of the retreating side wall surface 271 extending from the stepped surface 272 toward the back surface 2b are also used as core pads. 2. Integrally strengthen the frame 4 and surface pad 3.

In FIG. 3, in the surface pad 3, a seat layer 31 covers the top surface 2a of the core pad, and a side peripheral layer 32 covers the side wall surface 27 of the core pad 2. The upper surface of the seat layer 31 of the surface pad 3 becomes a designed surface 3a on the contact surface portion 311 side that the seated occupant comes into contact with, and the outer surface of the side circumferential layer 32 becomes the side surface side designed surface 3d of the surface pad 3. The surface pad 3 covers and is integrated with the core pad 2, except for the core pad back surface 2b which also serves as the cushion pad back surface 1b.
The surface pad 3 has its inner surface 3b in contact with the top surface 2a of the core pad 2 arranged at the inner lower part of the cushion pad 1, and enters into the groove 22, so that the frame main part 41 placed therein is The concave groove filling part 33 wraps around the groove. When the surface pad 3 is foam-molded, the frame main part 41 is buried inside the cushion pad, so the frame 4 does not fall off or come off, and exhibits its effectiveness as a reinforcing member for the cushion pad 1.
Thus, the surface pad 3 forms the seat layer 31 by bringing the inner surface 3b opposite to the contact surface portion 311 into contact with the top surface 2a, and also forms the groove filling portion 33 that fills the inside of the groove 22 into the frame 4. The cushion pad 1 is formed into a desired cushion pad 1 which is integrally foam-molded with the core pad 2 and the frame 4.

Note that although the back side hole opening 260 of the through hole 26 is exposed on the back side 1b of the cushion pad, it is not on the design side and does not pose a problem. 3A is the main part of the passenger seat, 3B is the side part, 3D is the slope, 3E is the joining part with the backrest, 391 is the vertical groove of the hanging groove 39, and 392 is the horizontal groove.

FIG. 11 is an alternative view of FIG. 2, showing a core pad 2 in which a lower region 29 is formed one step lower on the core pad top surface 2a at the front side of the vehicle and at the center in the vehicle width direction. By forming the low region portion 29, the groove 22 becomes intermittent, and the frame main portion 41 passing through the low region portion 29 is exposed without being accommodated in the groove 22. However, by fitting the other frame main portion 41 into the groove 22, the frame 4 within the dimensional tolerance can be placed and set on the core pad 2 while maintaining a predetermined accuracy. In addition, a mortar-shaped recess 241 and a through hole 24 are formed in the lower region 29 so that excess gas generated during foam molding of the surface pad 3 can be efficiently vented in the cushion pad manufacturing method described below. I have to.

(2) Manufacturing method of vehicle cushion pad The cushion pad 1 is manufactured, for example, by the following manufacturing method (FIGS. 6 to 10). Using the foaming mold 7, the surface pad 3 having at least the contact surface 311 on the side that the passenger contacts is made of a soft polyurethane foam molding is foam-molded, and the frame 4 is placed between the core pad 2 by the foam molding. (More specifically, this is a method for manufacturing a vehicle cushion pad in which the main frame portion 41 is embedded and integrated.)

Prior to manufacturing the cushion pad, the core pad 2, frame 4, and foam mold 7 are prepared. The core pad 2 and the frame 4 are the same as those described in (1) Cushion pad, and their explanation will be omitted.
The foaming mold 7 is a split mold as shown in FIG. 8, and a lower mold 8 and an upper mold 9 are connected so as to be openable and closable. When the mold is closed as shown in FIG. 9, there is a lower mold cavity surface 81 that is recessed into a bowl shape as a whole to form the design surface of the contact surface portion 311, and an upper mold cavity surface 91 that is generally flat as a whole and matches the back surface of the core pad 2. Create cavity C for cushion pad 1. On the upper mold cavity surface 91, when the core pad 2 is set in the upper mold 9, a convex protrusion 92 as shown in the figure protrudes at a position corresponding to the through hole 26, and a block-shaped magnet 93 (here Now fix the permanent magnet). The magnet 93 is a solid magnet or a flexible magnet, preferably a rare earth magnet containing a rare earth such as Nd or Sm, or a rare earth iron magnet, which has a strong magnetic force, and this embodiment also employs these solid magnets. When the core pad 2 with frame 4 is set on the upper mold cavity surface 91, the magnet 93 at the tip of the protrusion 92 inserted into the through hole 26 comes into contact with the frame 4 in the groove 22, and the frame 4 is It can be held by magnetic attraction (Figure 8).
The core pad 2 with the frame 4 arranged in the groove 22 is set on the upper mold cavity surface 91, and after the foaming raw material g is injected, the mold is closed and the surface pad 3 is foam-molded to produce the cushion pad 1 shown in FIG. 3. It has become a foam mold 7 that can be used. The foaming mold 7 shown in FIGS. 6 to 10 molds the cushion pad 1 shown in FIG. 3 upside down.

The manufacturing method of this cushion pad is to use the foaming mold 7 and the core pad 2 to turn the core pad 2 made of a foam molded product of foamable resin particles with its back side 2b facing up and the back side of the through hole 26. Insert the protrusion 92 of the upper mold 9 into the side hole opening 260 and set it in the upper mold 9 (FIG. 6). The through hole 26 penetrates from the groove bottom surface 221 of the groove 22 to the core pad back surface 2b. There are three (plural) through holes 26 and three projections 92, and by inserting each projection 92 into the respective through holes 26, the core pad 2 is autonomously positioned and adjusted and set on the upper mold cavity surface 91. In this embodiment, the through hole 26 is set so that the hole cross-sectional shape S26 becomes gradually smaller in the direction from the back surface 2b of the core pad 2 to the groove bottom surface 221 (see FIG. 3), and the hole cross-sectional shape has a protruding cross-section. Corresponding to the shape S92, the protrusion 92 is formed in a tapered shape toward the tip (FIG. 6). The tip of the protrusion 92 is smaller than the back side hole opening 260 of the through hole 26, so that the protrusion 92 of the upper die 9 can be easily inserted into the through hole 26.
Further, it is preferable to provide an engaging portion 925 at the base end of the projection 92 that bites into the hole wall 265 of the back side hole opening 260 of the through hole 26 when the projection 92 is inserted into the through hole 26 . Due to the presence of the engaging portion 925, when the protrusion 92 is inserted into the back side hole opening 260 of the through hole 26, the engaging portion 925 bites into the hole wall 265 of the back side hole opening 260 of the through hole 26, and the core The pad 2 is set and held on the upper mold 9. For example, FIGS. 13 and 14 are views of other aspects of the core pad 2 and the upper mold 9, in which the through hole 26 has a constant diameter, but the protrusion 92 has a substantially triangular cross section on the circumferential side 923 of the proximal end. A triangular protruding engaging portion 925 extending in the protruding direction of the protrusion 92 is set. When the protrusion 92 is inserted into the through hole 26 and the core pad 2 is set on the upper mold 9 as shown in FIG. 2 is set and held in the upper mold 9.

Next, the frame 4 is inserted into the groove 22 of the core pad 2 and set. In this embodiment, all the groove widths W22 of the grooves 22 are made larger than the shaft diameter t4 of the frame 4 so that the frame 4 has the flexibility to adjust the arrangement. I end up falling. However, in the present invention, when the core pad 2 is set on the upper mold cavity surface 91, the magnet 93 is exposed from the groove bottom surface 221 of the groove 22 as shown in FIG. The frame 4 is held by magnetic attraction (FIG. 7).
In this way, the core pad 2 is set in the upper die 9 with the top surface 2a facing downward, and the frame 4 placed in the groove 22 can be magnetically attracted by the magnet 93 and set in the groove 22. The frame 4 now follows the outer peripheral edge 21 of the core pad 2 (FIG. 8).
Thereafter, a foaming raw material g for a flexible polyurethane foam molded product is injected onto the lower mold cavity surface 81 using an injection nozzle NL or the like.

Next, the upper mold 9 is operated to close the mold (FIG. 9). By closing the upper mold 9 and the lower mold 8, a cavity C for the cushion pad 1 in which the core pad 2 with the frame 4 is inserted is formed. In this embodiment, the mold was closed after the foaming raw material g was injected, but the foaming raw material g could also be injected after the mold was closed.

After closing the mold, the process moves to foam molding of the surface layer pad 3. A surface pad 3 having a contact surface portion 311 on the design surface side and an inner surface 3b on the opposite side contacting the top surface 2a of the core pad 2 to form a seat layer 31 is foam-molded. The mold closed state shown in FIG. 9 is maintained for a predetermined period of time, and the surface pad 3 of the soft polyurethane foam molded product is foam-molded (FIG. 10). A concave groove that forms a contact surface portion 311 on the lower mold cavity surface 81, brings the inner surface 3b opposite to the contact surface portion 311 into contact with the top surface 2a of the core pad 2, and fills the inside of the concave groove 22 containing the frame 4. The surface layer pad 3 with the filling portion 33 formed thereon is foam-molded.

As the surface pad 3 is foam-molded, the foaming raw material g rises inside the cavity C under the closed mold, and the air and excess foaming gas existing in the cavity C pass through the through holes 24 and are released outside the mold. . In the cavity C in which the upside-down cushion pad 1 is molded, excess foaming gas collects not only in the mortar-shaped recess 241 and the through hole 24 provided on the top surface 2a of the core pad, but also in the through hole 26, and the through hole 26 collects. Excess gas is smoothly released from 26 to the outside of the mold. The truncated conical protrusion 92 inserted into the through hole 26 is provided with a gas venting groove 920 like a keyway in the vertical direction of its conical surface (FIG. 7). Excess foaming gas is released outside the mold. Note that illustration of the gas vent groove 920 is omitted except in FIG.
On the other hand, the liquid foaming raw material g foams up and fills the cavity C forming the surface layer pad 3, a part of it enters into the groove 22 to bury the frame 4, and fills the inside of the groove 22 to form the groove. It enters the filling portion 33 and further into the through hole 26 to form an entry hardening portion 36 (FIG. 3). Further, the surface pad 3 is formed by foam-molding, filling the depression 25 and the through hole 24 to form a depression filling part 35 and a through hole filling part 34, and covering the core pad 2 with the seat layer 31 and the side circumferential layer 32.

When the foam molding of the surface layer pad 3 is completed and the mold is removed, a cushion pad 1 is obtained in which the frame 4 maintains the desired dimensional accuracy and the weight is reduced by incorporating the core pad 2 (FIG. 3). Further, the core pad 2 and the surface pad 3 are connected by the groove filling part 33, the hardening part 36, the through hole filling part 34, the hollow filling part 35, the lower part 37 of the side circumferential layer 32, etc. A desired cushion pad 1 with enhanced bonding strength with 3 is completed.
Reference numeral 921 indicates the top surface of the protrusion, and reference numerals 89 and 99 indicate mold matching surfaces on the lower mold 8 side and the upper mold 9 side.

(3) Effect In the vehicle cushion pad and the manufacturing method thereof configured as described above, the separate frame 4 enters the core pad 2 which has been foam-molded with the groove 22 formed therein, and the core Since it is arranged on the pad 2, even if the core pad 2 shrinks during foam molding of expandable resin particles, the frame 4 is not affected by the mold shrinkage. The frame 4, which is preformed along the outer peripheral edge 21 of the core pad 2, can be placed and set in the groove 22 while maintaining its dimensional accuracy. Since the surface pad 3 is foam-molded by forming the groove filling part 33 that fills the groove 22 in the frame 4, the desired cushion pad 1 can be stably produced while the frame 4 maintains the dimensional accuracy.

According to Patent Documents 1 and 2, although the improvement is achieved to a certain extent, since the core pad 2 with frame 4 is still molded with the frame 4 embedded, the core pad with frame 4 may be damaged due to deformation such as warping or twisting due to molding shrinkage. 2 may become difficult to set in the upper die 9 of FIG. Further, even if the upper mold 9 is set, there is a problem that a gap is formed between the upper mold 9 and the back surface 2b of the core pad, and the foaming raw material g enters the gap during the subsequent foam molding of the surface layer pad 3. There is a slot on the back side 2b of the core pad for fixing a clip provided at the edge of the outer skin covering the cushion pad 1, and if there is such a gap, it will cause a problem that it will be filled in when the surface layer pad 3 is formed. Furthermore, the fact that the frame 4 is twisted or the like may cause problems in assembling the cushion pad 1 into a vehicle after it is completed.
In contrast, in the present invention, the frame 4 is placed in the groove 22 of the core pad 2 without applying any external force while maintaining the annular shape, and the surface pad fills the groove 22 containing the frame 4. Since 3 is the cushion pad 1 formed by foam molding, the frame 4 can maintain its initial shape. If the frame 4 is manufactured accurately within tolerance, it will not be affected by molding shrinkage during molding of the core pad 2. Therefore, foam molding of the surface layer pad 3 does not cause problems such as making it difficult to set it in the upper mold 9 or filling up the slot for fixing the clip. Further, after the cushion pad 1 is completed, the frame protrusion 42 can be smoothly attached to the vehicle without any hindrance. The frame 4 is arranged in the cushion pad 1 with high precision, contributing to quality improvement and yield improvement.

Moreover, in the present invention, the groove 22 is provided on the top surface 2a side of the core pad 2, so that the inner surface 3b of the surface layer pad on the opposite side to the contact surface portion 311 contacts the top surface 2a, and the inside of the groove 22 containing the frame 4 is made into contact with the top surface 2a. The frame 4 is sandwiched between the surface pad 3 and the core pad 2 to form the groove filling portion 33 to be filled. If the frame 4 is integrated into a part of the core pad 2 or is assembled along or near the back surface of the core pad 2, there is a risk that it will fall off from the core pad 2 when an external force is applied. 1, a frame main portion 41 is embedded in the contact surface between the core pad 2 and the surface pad 3. Since the frame main portion 41 is buried inside the cushion pad 1, the attachment and fixation to the vehicle can be ensured.

In addition, when the core pad 2 is provided with a through hole 26 penetrating from the groove bottom surface 221 of the concave groove 22 to the back surface 2b opposite to the top surface 2a, the back surface 2b side is directed toward the upper mold cavity surface 91, as shown in FIG. The core pad 2 can be set on the upper mold 9 as shown in FIGS. 6 to 8. By providing a plurality of through holes 26 and corresponding projections 92, the arrangement of the core pad 2 on the upper mold cavity surface 91 can be uniquely determined by simply inserting each projection 92 into the respective through hole 26. , the core pad 2 can be positioned and set on the upper mold cavity surface 91 very easily.
Furthermore, if an engaging portion 925 is provided at the base end of the protrusion 92 that bites into the hole wall 265 of the back side hole opening 260 of the through hole 26 when the protrusion is inserted into the through hole 26, the protrusion into the through hole 26 can be inserted into the through hole 26. 92, the engaging portion 925 can be bit into the hole wall 265 of the back side hole opening 260 of the through hole 26 as shown in FIGS. be done. The core pad 2 can be set on the upper die 9 even without a locking tool.

Then, a magnet 93 is fixed to the tip of the protrusion 92 so that the magnet 93 passes through the through hole 26 of the core pad 2 set in the upper mold 9 and looks into the groove bottom surface 221 as shown in FIG. The frame 4 can be set in the groove 22 by magnetically attracting the frame 4 to the groove 22. Even when the core pad 2 with frame 4 is set in the upper mold 9 and the cushion pad 1 is molded upside down as shown in FIG. 8, the frame 4 is placed and set in the groove 22. It can be maintained until the surface layer pad 3 is molded.

Furthermore, if the groove width W22 of the groove 22 is larger than the shaft diameter t4 of the frame 4, even if the contour shape of the groove 22 is slightly deformed due to molding shrinkage of the core pad 2, the frame 4 will maintain its shape. The position can be adjusted and set within the concave groove 22 while maintaining the position. The permissible range in which the core pad 2 can be received and the frame 4 can be placed and set within the groove 22 is widened, contributing to an improvement in yield.

In addition, the present cushion pad 1 has a problem in that the bonding force between the foam molded body of the expandable resin particles constituting the core pad 2 and the soft polyurethane foam molded body of the surface layer pad 3 is weak. Since the surface pad 3 can be foam-molded by forming the groove filling part 33 and the hardening part 36 that fill the inside of the groove 22, the two can be integrated by forming the groove filling part 33 and the hardening part 36.
Further, by providing the through holes 24 and the depressions 25 and forming the through hole filling portions 34 and the depression filling portions 35 by molding the surface pad 3, it is possible to further enhance the integral reinforcement of the core pad 2 and the surface pad 3. By providing the stepped surface 272 and the outwardly inclined surface 275 on the side wall surface 27 of the core pad 2, the lower portion 37 of the side circumferential layer 32 that prevents the core pad 2 from falling off from the surface pad 3 can be easily formed by molding the surface layer pad 3. Therefore, it is possible to obtain a cushion pad 1 in which the bonding force between the two is further increased.

Furthermore, by providing the gas vent groove 920 in the protrusion 92, excess gas during foam molding can be released outside the mold, and the protrusion 92 can be used in place of the through hole 24. Although not shown, if the portion of the through hole 26 where the hardened entry portion 36 is made is made larger like the recess 25 relative to the through hole 24, the hardened entry portion 36 can act as a part to prevent the core pad 2 from falling off the surface pad 3. is also helpful.
In addition, since the core pad 2 can be locked and set to the upper mold 9, when the mold is opened during demolding, the cushion pad 1 is locked to the upper mold 9. Since the worker can take out the cushion pad 1 while standing without bending his or her waist, work efficiency is improved.
As described above, the present vehicle cushion pad and its manufacturing method exhibit the various excellent effects described above and are extremely useful.

Note that the present invention is not limited to what is shown in the embodiments described above, and can be variously modified within the scope of the present invention depending on the purpose and use. The shape, size, number, material, etc. of the cushion pad 1, core pad 2, through hole 26, surface layer pad 3, frame 4, foam mold 7, protrusion 92, etc. can be appropriately selected according to the purpose.

1 Cushion pad 2 Core pad 2a Top surface 2b Back surface 22 Concave groove 221 Groove bottom surface 26 Through hole 260 Hole opening 3 Surface layer pad 3b Inner surface 31 Seat layer 311 Contact surface portion 33 Concave groove filling portion 4 Frame 81 Lower mold cavity surface 9 Top Mold 91 Upper mold cavity surface 92 Protrusion 93 Magnet g Foaming raw material

Claims (5)

A cushion pad for a vehicle in which at least the contact surface portion on the side that a seated occupant contacts is formed of a soft polyurethane foam molded product,
A core pad that is a foamed molded product of expandable resin particles, and has a groove on the top surface and a through hole penetrating from the bottom surface of the groove to the back surface opposite to the top surface;
an axial frame that is separate from the core pad and that enters the groove and is disposed on the core pad;
a soft polyurethane foam molded article, which has the abutment surface portion and has an inner surface on the opposite side thereof in contact with the top surface to form a seat layer, and a groove that fills the frame-filled groove; A surface layer pad forming a filling part and formed by foam molding ,
A cushion pad for a vehicle, wherein a plurality of the through holes are provided, and the cross-sectional shape of the through holes is set to become gradually smaller from the back surface of the core pad toward the bottom surface of the groove. A cushion pad for a vehicle in which at least the contact surface portion on the side that a seated occupant contacts is formed of a soft polyurethane foam molded product,
A core pad that is a foamed molded product of expandable resin particles, and has a groove on the top surface and a through hole penetrating from the bottom surface of the groove to the back surface opposite to the top surface;
an axial frame that is separate from the core pad and that enters the groove and is disposed on the core pad;
a soft polyurethane foam molded article, which has the abutment surface portion and has an inner surface on the opposite side thereof in contact with the top surface to form a seat layer, and a groove that fills the frame-filled groove; A surface layer pad forming a filling part and formed by foam molding,
The said through hole has a large diameter part larger than the hole diameter in the said groove bottom surface, and the said soft polyurethane foam molding has an intrusion hardening part which penetrates into this large diameter part from the said groove. A cushion pad for a vehicle in which at least the contact surface portion on the side that a seated occupant contacts is formed of a soft polyurethane foam molded product,
A core pad that is a foamed molded product of expandable resin particles, and has a groove on the top surface and a through hole penetrating from the bottom surface of the groove to the back surface opposite to the top surface;
an axial frame that is separate from the core pad and that enters the groove and is disposed on the core pad;
a soft polyurethane foam molded article, which has the abutment surface portion and has an inner surface on the opposite side thereof in contact with the top surface to form a seat layer, and a groove that fills the frame-filled groove; A surface layer pad forming a filling portion and formed by foam molding,
A cushion pad for a vehicle, wherein the entire shaft-like frame is disposed within the groove without being locked by the core pad. A cushion pad for a vehicle in which at least the contact surface portion on the side that a seated occupant contacts is formed of a soft polyurethane foam molded product,
A core pad that is a foamed molded product of expandable resin particles, and has a groove on the top surface and a through hole penetrating from the bottom surface of the groove to the back surface opposite to the top surface;
an axial frame that is separate from the core pad and that enters the groove and is disposed on the core pad;
a soft polyurethane foam molded article, which has the abutment surface portion and has an inner surface on the opposite side thereof in contact with the top surface to form a seat layer, and a groove that fills the frame-filled groove; A surface layer pad forming a filling part and formed by foam molding,
A cushion pad for a vehicle, wherein all groove widths of the grooves are larger than the width of the frame, and the grooves have a U-shape formed by recessing the top surface . In a method for manufacturing a cushion pad for a vehicle, in which at least the contact surface portion on the side that a seated occupant contacts is formed of a soft polyurethane foam molding,
A protrusion protruding from the upper mold cavity surface is inserted into the back side opening of a through hole that penetrates from the bottom of the groove formed on the top surface of the core pad made of a foam molded product of expandable resin particles to the back surface of the core pad. , setting the core pad on the upper mold, and magnetically attracting the shaft-shaped frame arranged in the groove to a magnet fixed to the tip of the protrusion, and setting the frame in the groove;
Next, a foaming raw material for a flexible polyurethane foam molded article is injected onto the lower mold cavity surface, and the mold is closed.
Thereafter, a seat layer is formed by having the contact surface portion on the lower mold cavity surface and bringing the inner surface on the opposite side into contact with the top surface of the core pad. A method for manufacturing a cushion pad for a vehicle, characterized in that a surface pad of a soft polyurethane foam molded product having a groove filling portion formed therein is foam-molded.

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