JP2018167551A - Integrally-molded body, and method for manufacturing integrally-molded body - Google Patents

Abstract

To provide an integrally-molded body and a method for manufacturing thereof capable of avoiding exposure of an uneven shape caused by an insert member.SOLUTION: An integrally-molded body 1 includes a sheet-like foam-molded body 3 and an insert member 2. The sheet-like foam-molded body 3 has a first surface 3da and a second surface 3b facing each other. The insert member 2 includes a body 2a and an extended portion 2b extended from the body 2a. The extended portion 2b is embedded in the foam-molded body 3 on the first surface 3da side.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an integrally molded body and a method for manufacturing the same.

  Some automobile interior members such as door trims may require attachment of insert members such as clips to a resin molded body (base material) made of thermoplastic resin for the purpose of assembly with other parts. . In such a case, an integrally molded body composed of the base material and the insert member is formed by introducing the resin into the cavity in a state where the insert member is disposed in the cavity of the mold. In Patent Document 1, a foamed resin sheet is obtained by reheating one foamed resin sheet to a softened state and placing the foamed resin sheet under reduced pressure from both molds. A technique is disclosed in which a sheet is subjected to secondary foaming to form a thick portion in a foamed molded product.

JP 2001-310380 A

  Thus, the integrally molded body used as the automobile interior member is required to have high designability with respect to the appearance (design surface) visually recognized by the consumer. For example, if the integrally molded body is a double wall body, the uneven shape derived from the insert member does not occur on the design surface side, but if it is a single wall body, the uneven shape appears on the design surface side and the design properties are reduced. It is assumed that Further, as a workaround, the product thickness is increased to a level at which the uneven shape does not appear, but the product weight increases, and the utility as a product may be impaired.

  This invention is made | formed in view of such a situation, and provides the integrally molded object which can avoid the exposure of the uneven | corrugated shape by an insert member, and its manufacturing method.

  According to a first aspect of the present invention, a sheet-like foam molded body and an insert member are provided, the foam molded body has first and second surfaces facing each other, and the insert member includes a main body portion. And an extending portion extending from the main body portion, and the extending portion is embedded in the foamed molded body on the first surface side. Is provided.

  In the integrally molded body according to the first aspect of the present invention, the base material is made of foamed resin and is lightweight, and the insert member is embedded in the base material and molded. Exposure of the concavo-convex shape derived from the insert member can be avoided. That is, an integrally molded body with higher practicality and design can be formed.

  In the present invention, a solid resin is not used for the substrate, but a foamed resin is used. In the case of a solid single wall body, it is necessary to increase the thickness of the base material in order to hide the unevenness. However, when a foamed resin is used, it is easy to make a lighter product than an unfoamed molded product. Moreover, since it is a foamed resin, it can be thickened by vacuum forming. At this time, when insert molding is performed only by increasing the bubble diameter, even if the product thickness is increased to a level at which the uneven shape does not appear, there is almost no need to change the product weight.

  Moreover, since it is a foamed resin compared with the conventional solid resin, it is anticipated that insert member pullout strength will fall. For this reason, by compressing the periphery of the place where the insert member is disposed, the pulling strength can be increased by improving the periphery of the resin to the insert member.

  As described above, according to the present invention, the insert member attaching portion can be pulled out without causing the uneven shape of the insert member attaching portion to appear on the design surface side, and even when the thickness of the base material is large, and by compressing the peripheral portion. A foam design with high strength and high design can be produced.

Hereinafter, various embodiments of the present invention will be exemplified. The following embodiments can be combined with each other.
Preferably, the second surface has a flat area corresponding to the insert member and a surrounding area.
Preferably, the foamed molded body includes first and second portions, in which the insert member is embedded, and t1> t2, where t1 is a thickness of the first portion. Yes, t2 is the thickness of the second portion.
Preferably, a groove is provided at a boundary between the first portion and the second portion.
Preferably, the second surface is covered with a skin member.
Preferably, the average thickness of the foam molded article is 20 mm or less.

  According to a second aspect of the present invention, there is provided a method for producing an integrally molded body using the first and second molds, the method comprising an insert step, an arrangement step, and a molding step. In the insert step, an insert member is mounted on the second mold, and in the placement step, the mold is interposed between the first and second molds with the insert member mounted on the second mold. The foamed resin in a molten state is suspended, and the insert member includes a main body part and an extending part extending from the main body part, and the extending part is embedded in the foamed resin in the molding step. A method is provided.

  In the second aspect of the present invention, the foamed resin sheet in a molten state is sucked under reduced pressure by both the first and second molds, whereby the air bubbles in the central part, which are less susceptible to cooling by the atmosphere and are low in viscosity, are stretched. It becomes possible to increase the wall thickness to the gap provided between them. For this reason, when an insert member is inserted, an uneven | corrugated shape cannot appear easily on the design surface side, and a flat molded object with high design property can be manufactured.

Preferably, the molding step includes an expansion step, and the expansion step includes the first and second molds such that a gap larger than the thickness of the foamed resin is provided between the first and second molds. The foamed resin is expanded to the thickness of the gap by sucking the foamed resin under reduced pressure by both the first and second molds while the mold is brought close to the mold.
Preferably, the expansion step includes a first suction step, a mold proximity step, and a second suction step in this order. In the first suction step, the foamed resin is sucked under reduced pressure by the first die. The foamed resin is shaped into a shape along the cavity of the first mold, and in the mold proximity step, the first and second molds are provided so that the gap is provided between the first and second molds. Two molds are brought close to each other, and in the second suction step, the foamed resin is expanded to the thickness of the gap by sucking the foamed resin under reduced pressure by the first and second molds.
Preferably, the second mold includes a convex portion that surrounds the mounting portion of the insert member, and in the expansion step, the convex portion presses the foamed resin to form a groove in the foamed resin.

It is a perspective view of the integrally molded body 1 which concerns on embodiment of this invention, and especially FIG. 1A has shown the 1st surface 3a side, and FIG. 1B has shown the 2nd surface 3b side. FIG. 2 is an exploded view of the integrally molded body 1 shown in FIG. 1 disassembled into an insert member 2 and a foam molded body 3. 3A is a plan view of the integrally molded body 1 shown in FIG. 1, FIG. 3B is a cross-sectional view taken along line P-P in FIG. 3A, and FIG. 3C is a partially enlarged view of FIG. 3B. It is a perspective view of the integrally molded body 1 which concerns on the modification which does not provide the 1st partial 1st surface 3ca and groove | channel 3e which are illustrated by FIG. 2 etc. FIG. An example of the foam molding machine which can be utilized with the manufacturing method of the integrally molded object 1 which concerns on embodiment of this invention is shown. FIG. 3 is a perspective view of first and second molds 21 and 22. Here, the vacuum suction holes 21a and 22a are not shown in view of visibility. It is the perspective view seen from the angle different from FIG. FIG. 8 is an end view showing the Q cross section of FIG. 7 for the first and second molds 21 and 22. FIG. 9 is an end view showing a state in which the insert member 2 is arranged and the foamed resin sheet 23 is suspended from the state of FIG. 8. FIG. 10 is an end view showing a state where the vacuum suction is performed through the vacuum suction hole 21 a continuously from the state of FIG. 9. FIG. 11 is an end view showing a state in which vacuum suction is performed through the vacuum suction hole 21a continuously from the state of FIG. FIG. 12 is an end view showing a state in which the foamed resin sheet 23 is expanded to the thickness of the gap G by performing vacuum suction through the vacuum suction hole 22a continuously from the state of FIG. The cross-sectional photograph of the foaming molding 3 obtained in the Example of this invention is shown. An example of a bubble form for explaining a method of calculating a temporary average bubble diameter is shown.

  Hereinafter, embodiments of the present invention will be described. Various characteristic items shown in the following embodiments can be combined with each other. In addition, the invention is independently established for each feature.

1. Integrated molded body 1
1A and 1B are perspective views showing an integrally molded body 1 according to an embodiment of the present invention. As shown in FIGS. 1A and 1B, an integrally molded body 1 according to an embodiment of the present invention is an automobile interior member such as a door trim, for example, and is an integrally molded body formed by insert molding. That is, the integrally molded body 1 includes an insert member 2 (for example, a clip) molded by injection molding or the like and a foam molded body 3 molded so that the insert member 2 is embedded. As shown in FIGS. 1A and 1B, the foam molded body 3 has a sheet-like shape and has a first surface 3a and a second surface 3b. Here, the first surface 3a is a surface to which the insert member 2 is attached, the second surface 3b is the back surface (so-called design surface), and corresponds to the region corresponding to the insert member 2 (that is, the second surface 3b is opposed). The region in which the insert member 2 is embedded in the first surface 3a and the surrounding region are flat. Although not shown in FIGS. 1A and 1B, the second surface 3b may be covered with a skin member such as a carpet. In addition, in the manufacturing method of the below-mentioned integral molded object 1, it demonstrates supposing the case where it covers with a skin member.

  FIG. 2 is an exploded view in which the integrally molded body 1 shown in FIG. 1A is disassembled into an insert member 2 and a foamed molded body 3. 3A is a plan view of the integrally molded body 1 shown in FIGS. 1A and 1B, FIG. 3B is a cross-sectional view taken along the line PP in FIG. 3A, and FIG. 3C is a partially enlarged view of FIG. 3B. It is. The insert member 2 may be a resin molded body or a metal molded body, and its manufacturing method is not particularly limited. As shown in FIG. 2, the insert member 2 includes a main body portion 2 a and an extension portion 2 b. In particular, as shown in FIGS. 3B and 3C, the main body portion 2a is adjacent to the embedded portion 2aa and the embedded portion 2aa embedded in the foamed molded body 3 via the first surface 3a in the integrally molded body 1. And the protrusion part 2ab which is not embedded in the foaming molding 3, but protrudes from the 1st surface 3a is provided. The extending part 2b is adjacent to the embedded part 2aa on the second surface 3b side with respect to the embedded part 2aa. The extending portion 2b extends in the surface direction related to the first and second surfaces 3a and 3b. With such a configuration, the insert member 2 is prevented from coming out of the foam molded body 3. In the present embodiment, as shown in FIG. 3A and the like, the shape of the extending portion 2b in a plan view is a substantially square shape, but this may be a substantially rectangular shape or a substantially circular shape.

  The foamed molded body 3 has the first and second surfaces 3a and 3b as described above. The foam molded body 3 includes a first portion 3c and a second portion 3d, which are two portions having different thicknesses. The first surface 3a for the two portions is defined as the first portion first surface 3ca and the first portion 3ca. This is referred to as a second partial first surface 3da. It arrange | positions so that the insert member 2 may be embedded in 1st part 1st surface 3ca. As shown in FIG. 3C, when the thickness of the first portion 3c is t1, and the thickness of the second portion 3d is t2, t1> t2. The value of t1 / t2 is, for example, 1.1 to 3.0. Specifically, for example, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1. 7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, and may be within a range between any two of the numerical values exemplified here.

  As shown in FIG. 3C, when the thickness of the extending portion 2b is t3, the value of t3 / t1 is, for example, 0.05 to 0.90, specifically, for example, 0.05, 0 .10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70 0.75, 0.80, 0.85, 0.90, and may be within a range between any two of the numerical values exemplified here.

  As shown in FIG. 3C, when the height of the embedded portion 2aa (that is, the depth at which the extended portion 2b is embedded from the first partial first surface 3ca) is h, the value of h / t1 is, for example, 0.05 to 0.80, specifically, for example, 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0. 45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, even within the range between any two of the numerical values exemplified here Good.

  As shown in FIGS. 3B and 3C, a groove 3e is provided at the boundary between the first partial first surface 3ca and the second partial first surface 3da. As shown in FIG. 3C, when the depth of the groove is d, the value of d / t2 is, for example, 0.05 to 0.90, specifically, for example, 0.05, 0.10, 0 .15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75 0.80, 0.85, and 0.90, and may be within a range between any two of the numerical values exemplified here. That is, the first portion 3c and the second portion 3d are defined with the groove 3e therebetween. In the present embodiment, as shown in FIG. 3A and the like, the first portion first surface 3ca has a substantially square shape, but the first portion first surface 3ca has a substantially rectangular shape or a substantially circular shape. 3e may be formed. Furthermore, it should be noted that the insert member 2 is only required to be prevented from falling off the foamed molded body 3, and the first partial first surface 3ca and the groove 3e are not essential components (see FIG. 4).

  Further, as shown in FIG. 3C, the length of one side of the first partial first surface 3ca in the surface direction is L1, the length of one side of the extending portion 2b in the same direction is L3, and the width of the groove 3e is Assuming w, the value of L3 / L1 is, for example, 0.30 to 0.80. Specifically, for example, 0.30, 0.35, 0.40, 0.45, 0.50,. 55, 0.60, 0.65, 0.70, 0.75, and 0.80, and may be within the range between any two of the numerical values exemplified here. The value of w / L1 is, for example, 0.01 to 0.30. Specifically, for example, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0 .07, 0.08, 0.09, 0.10, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19 , 0.20, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.30, illustrated here It may be within a range between any two of the numerical values.

  Note that the average thickness of the foamed molded body 3 in consideration of all of the first and second portions 3c, 3d and the groove 3e is preferably 20 mm or less. The average wall thickness is, for example, 1 to 20 mm. Specifically, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 17, 18, 19, 20 mm, and may be within a range between any two of the numerical values exemplified here.

2. Configuration of Foam Molding Machine 4 Next, a foam molding machine that can be used for carrying out the method of manufacturing an integrally molded body according to an embodiment of the present invention will be described with reference to FIGS. FIG. 5 shows an example of a foam molding machine that can be used in the method of manufacturing the integrally molded body 1 according to the embodiment of the present invention. The foam molding machine 4 includes a resin supply device 5, a T die 18, a first mold 21 and a second mold 22. The resin supply device 5 includes a hopper 12, an extruder 13, an injector 16, and an accumulator 17. The extruder 13 and the accumulator 17 are connected via a connecting pipe 25. The accumulator 17 and the T die 18 are connected via a connecting pipe 27. The T die can also be implemented using a cylindrical die core. Hereinafter, each configuration will be described in detail.

<Hopper 12, Extruder 13>
The hopper 12 is used for charging the raw resin 11 into the cylinder 13 a of the extruder 13. Although the form of the raw material resin 11 is not specifically limited, Usually, it is a pellet form. The raw material resin is, for example, a thermoplastic resin such as polyolefin, and examples of the polyolefin include low density polyethylene, linear low density polyethylene, high density polyethylene, polypropylene, ethylene-propylene copolymer, and a mixture thereof. The raw material resin 11 is poured into the cylinder 13a from the hopper 12 and then melted by being heated in the cylinder 13a to become a molten resin. Moreover, it is conveyed toward the front-end | tip of the cylinder 13a by rotation of the screw arrange | positioned in the cylinder 13a. A screw is arrange | positioned in the cylinder 13a and conveys molten resin by kneading | mixing by the rotation. A gear device is provided at the base end of the screw, and the screw is driven to rotate by the gear device. The number of screws arranged in the cylinder 13a may be one or two or more.

<Injector 16>
The cylinder 13a is provided with an injector 16 for injecting a foaming agent into the cylinder 13a. Examples of the foaming agent injected from the injector 16 include physical foaming agents, chemical foaming agents, and mixtures thereof, but physical foaming agents are preferred. As physical foaming agents, inorganic physical foaming agents such as air, carbon dioxide, nitrogen gas, and water, organic physical foaming agents such as butane, pentane, hexane, dichloromethane, dichloroethane, and their supercritical fluids are used. be able to. As the supercritical fluid, carbon dioxide, nitrogen or the like is preferably used. If nitrogen, the critical temperature is 149.1 ° C. and the critical pressure is 3.4 MPa or more. If carbon dioxide, the critical temperature is 31 ° C., the critical pressure. It is obtained by setting it to 7.4 MPa or more. Examples of the chemical foaming agent include those that generate carbon dioxide by a chemical reaction between an acid (eg, citric acid or a salt thereof) and a base (eg, sodium bicarbonate). The chemical foaming agent may be supplied from the hopper 12 instead of being injected from the injector 16.

<Accumulator 17, T-die 18>
The foamed resin obtained by melt-kneading the raw material resin and the foaming agent is extruded from the resin extrusion port of the cylinder 13 a and injected into the accumulator 17 through the connecting pipe 25. The accumulator 17 includes a cylinder 17a and a piston 17b that can slide inside the cylinder 17a, and foamed resin can be stored in the cylinder 17a. Then, by moving the piston 17b after a predetermined amount of foamed resin is stored in the cylinder 17a, the foamed resin is pushed out from the slit provided in the T-die 18 through the connecting pipe 27 to hang down the foamed resin sheet 23. Form.

<Molds 21 and 22>
6 and 7 are perspective views of the first and second molds 21 and 22. Here, the vacuum suction holes 21a and 22a are not shown in view of visibility. The foamed resin sheet 23 (see FIG. 9) is guided between the first mold 21 and the second mold 22 (they are collectively referred to as molds 21 and 22). As shown in FIGS. 8 to 12, the first mold 21 is provided with a number of vacuum suction holes 21 a, and the foamed resin sheet 23 is sucked under reduced pressure along the cavity 21 b of the first mold 21. It is possible to shape into different shapes. Further, as shown in FIGS. 6 and 8 to 12, a pinch-off portion 21d is provided so as to surround the cavity 21b. As shown in FIGS. 8 to 12, the second mold 22 is provided with a number of vacuum suction holes 22 a, and the foamed resin sheet 23 is sucked under reduced pressure along the cavity 22 b of the second mold 22. It is possible to shape into different shapes. As shown in FIGS. 7 to 12, a pinch-off portion 22d is provided so as to surround the cavity 22b.

  In the present embodiment, the second mold 22 is provided with an insert member arrangement portion 22e into which the insert member 2 can be inserted. Here, as an example, the number of insert member placement locations 22e is one, but a plurality of insert member placement locations 22e may be provided so that a plurality of insert members 2 can be placed. Here, it should be noted that the insert member 2 is disposed above the center of the second mold 22. Generally, the resin temperature tends to be higher on the upper side of the mold than on the lower side. That is, with this arrangement, the thickness of the insert member 2 when the insert member 2 is embedded in the foamed molded body 3 is improved. This also increases the pull-out strength of the insert member 2. Further, a convex portion 22 f is provided around the insert member placement portion 22 e in the second mold 22. When the molds 21 and 22 are clamped, the foamed resin around the insert member 2 is compressed by the convex portions 22f, which will be described in detail later.

3. Manufacturing Method of Integrally Molded Body 1 Here, a manufacturing method of the integrally molded body 1 according to the embodiment of the present invention will be described with reference to FIGS. The method of this embodiment includes an insert process, an arrangement process, and an expansion process. Details will be described below.

3.1 Insert Step In this step, in the opened molds 21 and 22 shown in FIG. 8, the insert member 2 molded in advance is placed at the insert member placement location 22 e in the second die 22. (FIG. 9). Here, the skin member 6 is assumed to be suspended between the molds 21 and 22 in advance. The method for inserting the second mold 22 may be a method using a robot in addition to a method of attaching by a human hand.

3.2 Arrangement Step In this step, as shown in FIG. 9, a single foamed resin sheet 23 formed by extruding the foamed resin in a molten state from the slit of the T die 18 and hanging down is formed between the molds 21 and 22. And it arrange | positions rather than the skin member 6 at the metal mold | die 22 side. That is, the skin member 6, the foamed resin sheet 23, and the insert member 2 are arranged in this order from the mold 21 to the mold 22. In the present embodiment, since direct vacuum molding is performed using the foamed resin sheet 23 extruded from the T die 18 as it is, the foamed resin sheet 23 is not cooled and solidified to room temperature before molding, The solidified foamed resin sheet 23 is not heated before molding. Further, the foamed resin sheet 23 of the present embodiment has a substantially uniform temperature immediately after being extruded from the slit, and is gradually cooled from the surface by the atmosphere while being suspended. And since it becomes hard to receive the influence of cooling by air | atmosphere, so that it goes to the center of the thickness direction of the foamed resin sheet 23, the temperature rises and the viscosity of the foamed resin sheet 23 of this embodiment goes to the center of the thickness direction. Has the property of lowering. Although the thickness of the foamed resin sheet 23 is not specifically limited, For example, it is 0.5-5.0 mm, Preferably, it is 1.0-3.0 mm. Specifically, this thickness is, for example, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0 mm. It may be within the range between any two of the numerical values exemplified here.

3.3 Expansion Step In this step, as shown in FIGS. 10 to 12, the molds 21 and 22 are placed so that a gap G larger than the thickness of the foamed resin sheet 23 is provided between the molds 21 and 22. The foamed resin sheet 23 is sucked under reduced pressure from both the molds 21 and 22 in a state of being close. Thereby, the foamed resin sheet 23 is expanded to the thickness of the gap G. At this time, the convex part 22f presses the foamed resin sheet 23 locally, and the said location is compressed. The location corresponds to the groove 3 e in the foamed molded body 3. By such compression, the foamed resin effectively wraps around the extending portion 2b of the insert member 2 disposed in the second mold 22, and the detachment of the insert member 2 is prevented. As a result of such molding, the first portion 3c is molded to be thicker than the second portion 3d, so that the insert member 2 does not protrude toward the second surface 3b. In other words, the second surface 3b has a flat region corresponding to the insert member 2 (that is, a region where the insert member 2 is embedded in the first surface 3a opposite to the second surface 3b) and its surrounding region. It will be formed as follows. As shown in FIGS. 10 to 12, in this step, the skin member 6 and the foamed resin sheet 23 are integrated on the mold 21 side. In addition, the said expansion | swelling process is not essential, For example, you may shape | mold so that the foamed resin sheet 23 may be crushed with the 1st and 2nd metal mold | die 21 and 22, and the insert member 2 may be embedded. In such a case, a cylindrical foamed parison may be employed instead of the foamed resin sheet 23.

  In the present embodiment, the molds 21 and 22 are provided with pinch-off parts 21d and 22d. When the molds 21 and 22 are brought close to each other until the pinch-off parts 21d and 22d come into contact with each other, a space surrounded by the pinch-off parts 21d and 22d. Becomes the sealed space S. A portion of the foamed resin sheet 23 in the sealed space S is the foamed molded body 3. On the other hand, a portion of the foamed resin sheet 23 outside the sealed space S is a burr 3f.

  The cavities 21b and 22b of the molds 21 and 22 are located between the molds 21 and 22 over the entire portion of the foamed resin sheet 23 that becomes the foamed molded body 3 (that is, the portion in the sealed space S). The gap G is configured to be substantially constant. When the foamed resin sheet 23 is sucked under reduced pressure by the molds 21 and 22 in this state, the foamed resin sheet 23 expands to the thickness of the gap G and the foamed molded body 3 is formed. Note that the pinch-off portions 21d and 22d are not essential, and the molds 21 and 22 may be brought close to each other so that a gap G is formed between the molds 21 and 22. However, if the vacuum suction is performed by the molds 21 and 22 in a state where the pinch-off portions 21d and 22d are brought into contact with each other and the sealed space S is formed, the pressure in the sealed space S is easily reduced, and thus the foamed resin sheet 23 is expanded. There is a merit that it is easy.

  The thickness of the gap G is not particularly limited, but is preferably 1.1 to 3.0 times the thickness of the foamed resin sheet 23. Specifically, (thickness of the gap G) / (thickness of the foamed resin sheet 23) is, for example, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1 .7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9 3.0, and may be within a range between any two of the numerical values exemplified here.

  The vacuum suction by the molds 21 and 22 may be started by the vacuum suction by the first mold 21 first, or the vacuum suction by the second mold 22 may be started first by the molds 21 and 22. The vacuum suction may be started simultaneously. Further, the vacuum suction by the first mold 21 may be stopped first, the vacuum suction by the second mold 22 may be stopped first, or the vacuum suction by the molds 21 and 22 may be stopped simultaneously. Good. The vacuum suction by the molds 21 and 22 may be started before the molds 21 and 22 are brought close to each other, or may be started after they are brought close to each other.

  When the foamed resin sheet 23 is sucked under reduced pressure by both the molds 21 and 22, foaming of the foamed resin sheet 23 is promoted and the foamed resin sheet 23 expands. Since the foamed resin sheet 23 has the lowest viscosity in the vicinity of the center in the thickness direction (the highest fluidity), the foaming in the vicinity of the center in the thickness direction is particularly promoted and the foamed resin sheet 23 expands. As a result, it is possible to obtain the foam molded body 3 having a configuration in which the average cell diameter in the layer near the center in the thickness direction (center layer) is large and the average cell diameter in the surface layer near the surface is small. Such a foam-molded product 3 has a sandwich structure in which a central layer having a large average cell diameter is sandwiched between surface layers having a small average cell diameter, and thus is lightweight and highly rigid.

  As shown in the cross-sectional photograph of FIG. 13, the foam molded body 3 obtained by the method of the present embodiment is a layer having a thickness of 10% from the surface of the foam molded body 3 to the thickness of the foam molded body 3. Is a surface layer, and a layer having a thickness of 25 to 50% from the surface of the foam molded body is a central layer, the average cell diameter of the central layer is larger than the average cell diameter of the surface layer. The ratio of (average cell diameter of the central layer) / (average cell size of the surface layer) is not particularly limited, but is, for example, 1.2 to 10. Specifically, this ratio is, for example, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 7.0, 8.0, 9.0, 10.0, exemplified here It may be within a range between any two of the numerical values.

  The average cell diameter of the entire foam molded body 3 in the thickness direction is, for example, 100 to 2000 μm. Specifically, the average bubble diameter is, for example, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1500, 2000 μm, and between any two of the numerical values exemplified here. It may be within the range. The average cell diameter of the surface layer is, for example, 80 to 500 μm. Specifically, the average bubble diameter is, for example, 80, 100, 150, 200, 250, 300, 350, 400, 450, 500 μm, and is within the range between any two of the numerical values exemplified here. May be. The average cell diameter of the central layer is, for example, 100 to 2000 μm. Specifically, the average bubble diameter is, for example, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, It may be within a range between any two of the numerical values exemplified here.

The average bubble diameter is measured by the following method.
First, as shown in FIG. 14, a cross-sectional photograph of the foamed molded product 3 is taken at a magnification of 50 times.
Next, five reference lines R1 to R5 extending in the thickness direction are drawn in the cross-sectional photograph. The interval between the reference lines is 500 μm.
For each reference line, count the number of bubbles that the reference line passes through in the layer to be measured (surface layer, center layer, or the entire thickness direction).
-For each bubble, measure the maximum length in the thickness direction (the length at the portion where the length in the thickness direction is the longest).
-According to Formula 1, a temporary average bubble diameter is calculated for each reference line. Further, the average bubble diameter is calculated by arithmetically averaging the temporary average bubble diameters calculated for each reference line.
(Expression 1) Temporary average bubble diameter = total maximum length of all counted bubbles / number of counted bubbles

  For example, in the example of FIG. 14, the number of bubbles through which the reference line R passes in the central layer is six, and the maximum length in the thickness direction for each bubble is 11 to 16. Therefore, in this example, the provisional average bubble diameter of the central layer is calculated by (l1 + l2 + l3 + l4 + l5 + l6) / 6.

  The expansion step is preferably performed by executing the first suction step, the mold proximity step, and the second suction step in this order. In the first suction step, as shown in FIG. 10, the foamed resin sheet 23 is sucked under reduced pressure by the first mold 21 to shape the foamed resin sheet 23 into a shape along the cavity 21 b of the first mold 21. . In the mold proximity process, the molds 21 and 22 are brought close to each other so that the gap G is provided between the molds 21 and 22 as shown in FIG. In the second suction step, as shown in FIG. 12, the foamed resin sheet 23 is expanded to the thickness of the gap G by sucking the foamed resin sheet 23 under reduced pressure by the molds 21 and 22.

  When vacuum suction by the molds 21 and 22 is started after the molds 21 and 22 are brought close to each other, the foamed resin sheet 23 comes into contact with the convex portion 22c of the mold 22 before the foamed resin sheet 23 is shaped. . Usually, the temperatures of the molds 21 and 22 are lower than the temperature of the foamed resin sheet 23. Therefore, when the foamed resin sheet 23 comes into contact with the convex portion 22c of the mold 22, the foamed resin sheet 23 is cooled and its viscosity increases. In addition, the followability of the molds 21 and 22 to the cavities 21b and 22b is deteriorated. On the other hand, when the expansion process is performed by executing the first suction process, the mold proximity process, and the second suction process in this order, the foamed resin sheet 23 has a shape along the cavity 21b of the first mold 21. Since it is minimized that the foamed resin sheet 23 comes into contact with the molds 21 and 22 before being shaped, the increase in the viscosity of the foamed resin sheet 23 is suppressed, and the foamed resin sheet 23 is removed from the mold 21. , 22 can be followed with high accuracy.

3.4 Finishing Step After the expansion step, the molds 21 and 22 are opened, the foamed molded product 3 with the burr 3f is taken out, and the burr 3f is cut off to obtain the foamed molded product 3. The insert member 2 is embedded in the foamed molded body 3, that is, a desired integral molded body 1 can be obtained.

4). Conclusion According to the integrally molded body 1 according to the present embodiment, the following effects can be obtained.
(1) Since a foamed resin is used as a raw material for the base material, a lighter product than an unfoamed molded product can be produced. Moreover, since it is a foamed resin, it can be thickened by vacuum forming as described above. At this time, only the bubble diameter is increased, and there is almost no need to change the product weight even if the product thickness is increased to a level at which the uneven shape does not appear when insert molding is performed.
(2) Since it is a foamed resin as compared with a conventional solid resin, it is expected that the pull-out strength of the insert member is lowered. For this reason, by compressing the periphery where the insert member 2 is embedded (compressed portion 23e, groove 3e), the resin around the insert member 2 can be improved and the pulling strength can be increased.

  As described above, according to the present embodiment, the uneven shape of the mounting portion of the insert member 2 does not appear on the second surface 3b (design surface) side, and the thickness of the foam molded body 3 (base material) is large. However, it is possible to manufacture an integrally molded body 1 that is lightweight and has high practicality and design.

  Although the embodiment according to the present invention has been described, these are presented as examples and are not intended to limit the scope of the invention. The novel embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. The embodiments and the modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

1: Integrated molded body 2: Insert member 2a: Body portion 2aa: Embedded portion 2ab: Protruding portion 2b: Extending portion 3: Foam molded body 3a: First surface 3b: Second surface 3c: First portion 3ca: First 1 part 1st surface 3d: 2nd part 3da: 2nd part 1st surface 3e: Groove 3f: Burr 4: Foam molding machine 5: Resin feeder 6: Skin member 11: Raw material resin 12: Hopper 13: Extruder 13a : Cylinder 16: Injector 17: Accumulator 17a: Cylinder 17b: Piston 18: T die 21: First mold 21a: Depressurized suction hole 21b: Cavity 21d: Pinch-off part 22: Second mold 22a: Depressurized suction hole 22b: Cavity 22c: convex part 22d: pinch-off part 22e: insert member arrangement part 22f: convex part 23: foamed resin sheet 25: connecting pipe 27: connecting pipe

Claims (10)

A sheet-like foamed molded article and an insert member;
The foamed molded article has first and second surfaces facing each other,
The insert member includes a main body portion and an extending portion extending from the main body portion,
The extending portion is embedded in the foamed molded body on the first surface side.
Integrated molded body. In the second surface, a region corresponding to the insert member and a surrounding region thereof are flat.
The integrally molded body according to claim 1. The foamed molded body includes first and second portions,
In the first part, the insert member is embedded,
t1> t2, and
The t1 is the thickness of the first portion, and the t2 is the thickness of the second portion.
The integrally molded body according to claim 1 or 2. A groove is provided at a boundary between the first portion and the second portion.
The integrally molded body according to any one of claims 1 to 3. The second surface is covered with a skin member,
The integrally molded body according to any one of claims 1 to 4. The foam molded article has an average thickness of 20 mm or less,
The integrally molded body according to any one of claims 1 to 5. A method of manufacturing an integrally molded body using first and second molds,
The method includes an insert process, an arrangement process, and a molding process,
In the insert step, an insert member is attached to the second mold,
In the arranging step, the foamed resin in a mold molten state is suspended between the first and second molds in a state where the insert member is mounted on the second mold,
The insert member includes a main body portion and an extending portion extending from the main body portion, and the extending portion is embedded in the foamed resin in the molding step.
Method. The molding step includes an expansion step,
In the expansion step, the first and second molds are brought close to the first and second molds so that a gap larger than the thickness of the foamed resin is provided between the first and second molds. Expanding the foamed resin to the thickness of the gap by vacuum suctioning the foamed resin with both molds;
The method of claim 7. The expansion step includes a first suction step, a mold proximity step, and a second suction step in this order,
In the first suction step, the foamed resin is sucked under reduced pressure by the first mold, and the foamed resin is shaped into a shape along the cavity of the first mold,
In the mold proximity step, the first and second molds are brought close to each other so that the gap is provided between the first and second molds.
In the second suction step, the foamed resin is expanded to the thickness of the gap by sucking the foamed resin under reduced pressure by the first and second molds.
The method of claim 8. The second mold includes a convex portion surrounding the mounting portion of the insert member,
In the expansion step, the convex portion presses the foamed resin to form a groove in the foamed resin.
10. A method according to claim 8 or claim 9.