JP2010023403A - Foamed resin molded product and its molding method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture a void-free vehicular seat pad by preventing gas from remaining in the vicinity of the end part of a cavity. <P>SOLUTION: The seat back pad 1 includes a main plate 2 the front surface of which a passenger's back contacts, an extension part 3 extending backward from the upper margin of the main plate 2, left and right side margins, and an overhanging part 4 overhanging from the extension part 3 to the central side of the back surface of the main plate part 2. The overhanging part 4 mounted along the upper margin of the seat back pad 1 sags from the extension part 3. A shell-like body 5 is mounted on the overhanging part 4 on the main plate 2 side. The shell body 5 is composed of a non-woven fabric having a V-shaped cross section, and has an opening 5e on the extension part 3 side. The foamed resin constructing the overhanging part 4 is filled in the shell body 5 to construct an embedded body. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a foamed resin molded article suitable for application to a vehicle seat pad, and in particular, a vehicular seat back pad in which an overhang is provided at the periphery of the back surface, and an embedded body is provided in the overhang. The present invention relates to a foamed resin molded article suitable as The present invention also relates to a method for molding the foamed resin molded product.

  A protruding portion is provided on the back surface of the upper edge of the seat back pad so as to protrude downward. When a seat back pad having such an overhanging part is foam-molded by a mold, gas remains in the overhanging part and voids are easily generated (Patent Document 1 below). The reason for this will be described with reference to FIGS.

  The molding die (mold) 20 includes a lower die 21, an upper die 22 and a core 23. The upper mold 22 and the core 23 are connected to one end side of the lower mold 21 through support shafts 24a and 24b so as to be opened and closed.

  The cavity has a first space 25a for molding the main plate portion 31 of the seat back pad, a second space 25b for molding the extension portion 32, and a third space 25c for molding the overhang portion 33.

  In order to mold a vehicle seat back pad using the molding die 20, first, a foamed resin material is injected into the first space 25a in a state where the mold is opened. Further, a covering sheet 26 (refer to FIG. 5) commonly referred to as a support material is pasted on the molding surface of the core 23 with, for example, a double-sided tape. In this state, the core 23 and the upper mold 22 are closed to foam the foamed resin material.

  The foamed resin material in the first space 25a fills the first space 25a, the second space 25b, and the third space 25c in this order as the foaming progresses. The gas in the cavity is discharged to the outside from between the mating surfaces of the mold, but if the gas remains in the third space 25c without being completely removed, a void B is generated as shown in FIG. Appearance is impaired.

  In Patent Document 1, an embedded body (auxiliary foam) 27 having a mountain-shaped cross section is disposed in the third space 25c as shown in FIG. When the embedded body 27 is provided, the height of the space is gradually narrowed from the second space 25b side to the top position of the embedded body 27 in the third space 25c. The space height is gradually narrowed from the top position of the embedded body 27 toward the tip of the third space 25c. For this reason, the foamed resin (urethane) M that has flowed into the third space 25c flows smoothly through the flow path in the third space 25c while gradually increasing the flow velocity. As a result, the gas in the third space 25c is smoothly pushed out of the molding die 20 from between the mating surfaces of the upper mold 22 and the core 23, and the foamed resin M fills the third space 25c smoothly. To do. Thereby, generation of void B is prevented.

  FIG. 8 is a longitudinal sectional view of the seat back pad 30 formed in this way, 31 is a main plate portion, 32 is an extended portion extending rearward from the upper edge of the main plate portion 31, and 33 is the An overhanging portion that hangs down from the rear end of the extending portion 32 is shown. The back of the occupant comes into contact with the front surface of the main plate portion 31.

Patent Document 2 also describes providing a similar buried body.
JP 2008-23084 A JP2007-23084

  In the conventional vehicle seat back pad 30 described above, the embedded body 27 is formed by bonding resin foam chips with a binder, and is temporarily fixed to the covering sheet 26 with double-sided tape (0017, 0021 of Patent Document 1). Paragraph). Since the embedded body 27 is bulky, if it is integrated with the covering sheet in advance, the covering sheet becomes bulky and transportation efficiency is low. If the embedded body 27 is attached to the covering sheet 26 in the molding process, the work is troublesome and the manufacturing efficiency is low.

  Such a problem is a foamed resin molded product having a main part and a sub part connected to the main part, and the foamed resin expands the resin material from the main part toward the sub part. It is generally common to foamed resin molded products that are molded.

  An object of the present invention is to efficiently produce a foamed resin molded article such as a vehicle seat pad that is free from residual gas in the vicinity of a cavity end and has no voids.

  The foamed resin molded article according to claim 1 is a foamed resin molded article having a main part and a sub part connected to the main part, wherein the foamed resin is a resin material from the main part toward the sub part. Foamed resin molded product that is molded so as to expand, and the sub-portion is provided with an embedded body extending in a direction crossing the direction from the main portion toward the sub-portion In the product, the embedded body is characterized by comprising a shell-like body filled with a foamed resin constituting the sub part.

  A foamed resin molded article according to a second aspect is characterized in that, in the first aspect, an opening is provided on a surface of the shell-like body on the main part side.

  The foamed resin molded product according to claim 3 is the foamed resin molded product according to claim 1 or 2, wherein a support material is provided on an outer surface of at least a sub-portion of the foamed resin molded product, and the shell is connected to the support material. It is characterized by this.

  According to a fourth aspect of the present invention, the foamed resin molded product according to any one of the first to third aspects is characterized in that the shell is made of a nonwoven fabric.

The foamed resin molded product according to claim 5 is the foamed resin molded product according to any one of claims 1 to 4, wherein the foamed resin molded product is a vehicle seat pad, and the main portion is a main plate portion having an occupant contact surface. There is provided an extending portion extending from at least a part of the periphery of the main plate portion in a direction opposite to the occupant contact surface, and the sub-portion extends from the extended portion to the center of the back surface of the main plate portion. The overhanging part
The embedded body is provided on the main plate portion side of the overhang portion.

  According to a sixth aspect of the present invention, the foamed resin molded product according to the fifth aspect is characterized in that the embedded body extends in a direction substantially perpendicular to the extending direction of the protruding portion.

  The foamed resin molded product according to claim 7 is the foamed resin molded product according to claim 5 or 6, wherein a sheet-like support material is provided on the back surface of the vehicle seat pad, and the shell is connected to the support material. It is characterized by.

The foamed resin molded product according to claim 8 is the foamed resin molded product according to claim 7, wherein the length L in the extending direction of the shell-like body is 30 to 150 mm, the length in the extending direction is 30 to 300 mm, and A thickness h ₁ from the surface on the main plate portion side of the protruding portion to a surface on the opposite side thereof, and a thickness h _{2 in a} direction from the main plate portion side of the shell toward the inner side of the overhang portion The difference (h ₁ −h ₂ ) is 10 to 30 mm.

  According to a ninth aspect of the present invention, in the foamed resin molded product according to any one of the fifth to eighth aspects, the vehicle seat pad is a front seat back pad.

  A method for molding a foamed resin molded product according to claim 10 is a method for molding the foamed resin molded product according to any one of claims 1 to 9, wherein the shell-like body is placed in a mold and foam molding is performed. It is characterized by doing.

  The foamed resin molded product of the present invention (Inventions 1 to 9) is molded by the molding method of the present invention (Invention 10). In this foamed resin molded product, a buried body is constituted by the shell-like body and the foamed resin filled in the shell-like body. For example, when this shell-like body has an opening on the extending portion side and the shell-like body is attached to a support material and foamed, the resin that has entered the overhanging portion while being foamed is filled into the shell-like body. The buried body is constructed.

  Since the shell is not bulky, the support material is not bulky even if it is attached to the support material in advance, and the transport efficiency of the support material is good.

  When the shell is made of a nonwoven fabric such as felt, the nonwoven fabric has good gas permeability, so no gas remains in the shell and the generation of voids is prevented.

  The present invention is suitable for application to a front seat back pad.

  Hereinafter, embodiments will be described with reference to the drawings.

  FIG. 1 (a) is a perspective view from the back of a seat back pad for a front seat of an automobile according to the embodiment, FIG. 1 (b) is a sectional view taken along the line BB of FIG. 1 (a), and FIG. ) Is an enlarged view of a part of FIG. 2B, FIG. 2A is a sectional view of a part of a mold for forming a seat back pad, and FIG. 2B is a BB line of FIG. It is sectional drawing. FIG. 3 is a perspective view of the shell. FIG. 4 is a perspective view showing another example of the shell-like body.

  As shown in FIG. 1, the vehicle seat back pad 1 includes a main plate portion 2 on which the occupant's back hits the front surface, and an extended portion 3 extending rearward from the upper edge and left and right side edges of the main plate portion 2. And an overhanging portion 4 projecting from the extending portion 3 toward the center of the back surface of the main plate portion 2. In the overhanging portion 4 provided along the upper edge of the seat back pad 1, the overhanging portion 4 hangs from the rear portion of the extending portion 3.

  An embedded body is provided on the main plate portion 2 side of the overhang portion 4 along the upper edge portion of the seat back pad 1. As shown in FIG. 1 (a), the embedded body extends in the left-right direction of the seat back pad 1. The buried body is composed of a shell-like body 5 and a foamed resin filled in the shell-like body. A support material (covering sheet) 6 is provided from the back surface of the main plate portion 2 to the extending portion 3.

  This shell-shaped body 5 has a V-shaped cross-sectional shape, and is directed to the front inclined piece 5a on the extending portion 3 side, the rear inclined piece 5b on the opposite side, and the front inclined piece 5a toward the extending portion 3. The front flange piece 5c extends, the rear flange piece 5d extends from the rear oblique piece 5b in the opposite direction to the front flange piece 5c, and a plurality of openings 5e provided in the front oblique piece 5a. The total opening area of the openings 5e is preferably about 10 to 100%, particularly 50 to 100%, especially 50 to 95% of the area of the front oblique piece 5a. It is preferable that 1 to 4 openings 5 e are provided at intervals in the longitudinal direction of the shell 5.

  The shell 5 is preferably made of a nonwoven fabric such as felt. Since the nonwoven fabric is well-familiar with foamed resin materials (for example, foamed polyurethane, foamed polystyrene, foamed polyethylene, etc.) and has excellent gas permeability, gas is prevented from remaining in the shell 5.

  The seat back pad 1 is formed by using a mold 10 shown in FIG.

  The mold 10 includes a lower mold 11, an upper mold 12 and a core 13. The upper mold 12 and the core 13 are connected to one end side of the lower mold 11 through a support shaft (not shown) so as to be opened and closed.

  The cavity has a first space 15 a for molding the main plate portion 2, a second space 15 b for molding the extension portion 3, and a third space 15 c for molding the overhang portion 4.

  In order to mold the seat back pad 1 using the mold 10, first, a urethane stock solution as a foamed resin material is injected into the first space 15a in a state where the mold is opened. In addition, a support material (covering sheet) 6 is pasted on the molding surface of the core 13 with, for example, a double-sided tape. Note that the flange 5c, 5d of the shell 5 is attached to the support member 6 in advance by sewing, bonding or the like. Therefore, the shell 5 is also set on the core 13 simply by attaching the support material 6 to the core 13. As described above, the opening 5e of the shell 5 is directed to the second space 15b for forming the extension part 3. In this state, the core 13 and the upper mold 12 are closed to foam the foamed resin material.

  The urethane stock solution in the first space 15a fills the first space 15a, the second space 15b, and the third space 15c in this order as the foaming proceeds. The gas in the cavity is discharged to the outside from between the mating surfaces of the mold 10.

  In this embodiment, the shell-like body 5 is arranged near the entrance of the third space 15c so that the opening 5e faces the second space 15b. Therefore, the second space 15b is lifted and the third space 15c is raised. The urethane foam that has entered is first received by the shell 5 and gradually flows into the third space 15c. Specifically, the urethane foam that has progressed from the second space 15 b to the third space 15 c enters the shell 5 and fills the shell 5. Thereafter, the urethane foam gradually flows into the innermost portion of the third space 15c, that is, the cavity end C so as to get over the shell 5. As a result, the gas in the third space 15c is sufficiently discharged from the mating surface (parting line PL) between the upper mold 12 and the core 13 near the end C of the cavity, and voids are generated in the molded product. Is prevented. The parting line PL is closer to the distal end side of the overhanging portion 4 than the shell 5.

  In this embodiment, since the shell-like body 5 is made of a nonwoven fabric such as felt that is easily infiltrated with urethane and has good gas permeability, generation of voids is prevented.

  In this embodiment, since the shell 5 is attached to the support material 6 in advance, the work efficiency when the shell 5 and the support material 6 are set in the mold (core 13) is high, and the core 13 can be easily fitted.

  The width L in the overhanging direction (the length in the substantially vertical direction in FIG. 1C) L of the inner volume portion of the shell 5 is preferably about 30 to 150 mm, particularly about 40 to 50 mm. Since the cross-sectional shape of the shell-like body 5 is V-shaped, the width of the base portion in contact with the support material 6 is L.

In the state where the front oblique piece 5a and the rear oblique piece 5b of the shell-like body 5 are pinned in a flat plate shape and the shell-like body 5 has a V-shaped cross-sectional shape, the height of the third space 15c, that is, the overhanging portion 4 A thickness h ₁ from the surface on the main plate portion 2 side to a surface on the opposite side thereof, and a thickness h ₂ in the direction from the main plate portion 2 side to the inner side of the overhang portion 4 of the shell 5 The difference h ₁ −h ₂ is preferably 10 ≦ (h ₁ −h ₂ ) ≦ 30 mm, particularly preferably 15 ≦ (h ₁ −h ₂ ) ≦ 25 mm.

  The length of the seat back pad in the left-right direction of the shell 5 is preferably about 30 to 300 mm, particularly about 200 to 300 mm.

Incidentally, the inflow rate of the urethane foam from the second space 15b come to flow into the third space 15c (volume rate) and V _1, the volume rate of the urethane foam that passes through the arrangement portion of the shell-like body 5 V ₂ In this case, by setting the size and arrangement of the shell 5 so that V ₁ and V ₂ are substantially equal, a gas such as air that has been pushed from the second space 15b to the third space 15c. It becomes easy to hold the urethane foam.

Omitting the shell-like body 5, greater than V ₁ is V _2, urethane urethane spread within the volume when flowing into the third space 15c, urethane foam is less likely to retain the gas. Furthermore, since the viscosity is increased, if the volume suddenly increases, the urethane foam becomes difficult to hold the gas, and the urethane filling is delayed. Further, gas remains on the ceiling side of the third space 15c, and defects such as voids occur.

[Other embodiments]
As shown in FIG. 4A, the shell may be a shell 16 having a substantially semicircular or substantially U-shaped cross section, or a shell 17 having a square cross section. The shell-like body 16 includes a substantially semicircular or substantially U-shaped main body portion 16a, a front flange piece 16b extending from the front edge of the main body portion 16a toward the front, that is, in the second space 15b, and the main body portion 16a. A rear flange piece 16c extending from the rear edge in the opposite direction to the front flange piece 16b, and an opening 16d provided on the surface of the main body portion 16a on the second space 15b side.

  The shell 17 includes a top piece 17a, a front leg piece 17b and a rear leg piece 17c depending from the front edge and the rear edge of the top piece 17a, and a front flange piece 17d extending forward from the lower end of the front leg piece 17b. The rear flange piece 17e extends rearward from the lower end of the rear leg piece 17c, and the opening 17f is provided in the front leg piece 17b.

  In the shells 16 and 17, the flange pieces 16b, 16c, 17d, and 17e are attached to the support material so that the openings 16d and 17f are directed to the front, that is, the second space 15b.

  Although illustration is omitted, the cross-sectional shape of the shell may be trapezoidal or polygonal. Further, the number of shells is not limited to one, and a plurality of shells may be installed.

  In the present invention, the embedded body may be disposed at a place other than the figure.

  The present invention is a foamed resin molded article having a main part other than a seat pad and a sub part continuous to the main part, and the foamed resin is made of a resin material from the main part toward the sub part. You may apply to shaping | molding of the foamed resin molded product which was shape | molded so that it might expand | swell.

FIG. 1 (a) is a perspective view from the back of a seat back pad for a front seat of an automobile according to the embodiment, FIG. 1 (b) is a sectional view taken along the line BB of FIG. 1 (a), and FIG. ) Is an enlarged view of a part of FIG. FIG. 2 (a) is a partial cross-sectional view of a seat back pad molding die, and FIG. 2 (b) is a cross-sectional view taken along the line BB of FIG. 2 (a). It is a perspective view of a shell-like body. It is a perspective view which shows another shape of a shell-shaped body. It is sectional drawing of the metal mold | die which shows a prior art example. It is sectional drawing of a part of seat back pad which shows a prior art example. It is sectional drawing of the metal mold | die in the middle of shaping | molding which shows a prior art example. It is sectional drawing of the seat back pad which shows a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,30 Seat back pad 2,31 Main plate part 3,32 Extension part 4,33 Overhang part 5,16,17 Shell-like body 27 Embedded body 10,20 Mold 11,21 Lower mold 12,22 Upper mold 13 , 23 core

Claims (10)

A foamed resin molded product having a main part and a sub part connected to the main part,
The foamed resin is a foamed resin molded product formed such that a resin material expands from the main part toward the sub part,
In the foamed resin molded article provided with an embedded body extending in the direction intersecting with the direction from the main part to the sub part in the sub part,
The embedded resin article is a foamed resin molded product comprising a shell-like body filled with a foamed resin constituting the sub part.   2. The foamed resin molded product according to claim 1, wherein an opening is provided in the surface of the shell-like body on the main part side.   3. The foamed resin molded product according to claim 1, wherein a support material is provided on an outer surface of at least a sub part of the foamed resin molded product, and the shell is connected to the support material.   The foamed resin molded product according to any one of claims 1 to 3, wherein the shell is made of a nonwoven fabric. The foamed resin molded product according to any one of claims 1 to 4, wherein the foamed resin molded product is a vehicle seat pad.
The main portion is a main plate portion having an occupant contact surface, and an extended portion is provided extending in the opposite direction from the occupant contact surface from at least a part of the periphery of the main plate portion.
The sub-portion is an overhang portion that projects from the extension portion to the center side of the back surface of the main plate portion,
A foamed resin molded product, wherein the embedded body is provided on the main plate portion side of the overhang portion.   6. The foamed resin molded product according to claim 5, wherein the embedded body is extended in a direction substantially orthogonal to a protruding direction of the protruding portion.   7. The foamed resin molded product according to claim 5, wherein a sheet-like support material is provided on the back surface of the vehicle seat pad, and the shell is connected to the support material. In Claim 7, the length L in the projecting direction of the shell-shaped body is 30 to 150 mm, the length in the extending direction is 30 to 300 mm, and from the surface of the projecting portion on the main plate portion side. and the thickness h ₁ to the surface opposite thereto, the difference between the thickness h ₂ direction toward the inner side of the overhung portion from the main plate side of the shell-like body (h 1 _{-h 2)} is A foamed resin molded product characterized by having a thickness of 10 to 30 mm.   9. The foamed resin molded product according to claim 5, wherein the vehicle seat pad is a front seat back pad.   A method for molding a foamed resin molded article according to any one of claims 1 to 9, characterized in that the shell-like body is placed in a mold for foam molding. .

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