JP3176075U - Foamed resin molds and dissimilar foamed resin molded products - Google Patents

Abstract

The present invention provides a foamed resin molding die and a different kind of foamed resin molded product capable of increasing the joint strength at the joint interface between different kinds of foamed resin materials.
A foamed resin molding die includes a shutter 40 that slidably protrudes from a fixed die 20 side with respect to a movable die 30 to partition a cavity 12. The first cavity 24 and the second cavity 27 partitioned by the shutter are filled with the first foamed resin particles 50 and the second foamed resin particles 60 made of foamed resin materials having different foaming ratios, respectively, and the shutter is slid open. By heating, foamed resins having different foaming ratios are continuously formed. It has a side groove 22 that is recessed in the inner surface of the fixed mold and fits in the side of the shutter, and a bottom groove 32 that is recessed in the inner surface of the movable mold and fits in the tip of the shutter. The widths W and W ′ allow any foamed resin material to enter when the shutter is slid open and heated.
[Selection] Figure 2

Description

  The present invention relates to a foamed resin molding die for continuously molding a different foamed resin material and a different foamed resin molded product.

  A foamed resin molded product is obtained by filling a cavity of a foamed resin molding mold having a fixed mold and a movable mold movable with respect to the fixed mold with particles of the foamed resin material and heating the inside of the mold. It is produced by thermally expanding the particles.

  A different type of foamed resin molded article is known in which different foaming resin materials having different foaming ratios are used, and the foaming ratio changes midway. For example, in Patent Document 1, a cavity of a foamed resin molding mold composed of a fixed mold and a movable mold is partitioned by a shutter that can protrude and retract from the fixed mold, and each of the cavities partitioned by the shutter is filled with foamed resin particles having different foaming ratios. The molding is performed by opening the shutter and heating.

JP 2006-123732 A

When the difference in foaming ratio between the foamed resin materials becomes large (for example, a density difference of 0.03 g / cm ³ or more), the joint strength between the different foamed resin materials becomes weak, and there is a risk of peeling at the joint interface. is there.

  An object of the present invention is to provide a foamed resin molding die and a different type of foamed resin molded product that can increase the joint strength at the joint interface between different kinds of foamed resin materials.

The foamed resin mold according to the present invention is
A cavity formed by a fixed mold and a movable mold;
Provided with a shutter that slidably moves from the fixed mold side to the movable mold to partition the cavity,
By filling the first cavity and the second cavity partitioned by the shutter with the first foamed resin particles and the second foamed resin particles made of foamed resin materials having different foaming ratios, respectively, and by opening the shutter and heating it. A foamed resin molding die for continuously molding foamed resins having different foaming ratios,
A side groove recessed in the inner surface of the fixed mold and into which a side portion of the shutter is fitted;
A bottom groove recessed in the inner surface of the movable mold, into which the tip of the shutter fits;
Have
The side groove and the bottom groove have such a width that any foamed resin material enters when the shutter is slid open and heated.

In addition, the different foamed resin molded product of the present invention is
A different type of foamed resin molded product obtained by continuously molding a first foamed resin material and a second foamed resin material having different foaming ratios,
At the joining interface between the first foamed resin material and the second foamed resin material, a ridge that protrudes from the first foamed resin material is formed on the outer periphery.

According to the foamed resin molding die of the present invention, when the shutter is slid open, any one of the foamed resin particles enters the side groove and the bottom groove. The foamed resin material that has entered the side groove and the bottom groove becomes a raised ridge protruding from the outer periphery of the joint interface between the first foamed resin material and the second foamed resin material in the different foamed resin molded product.
The different foamed resin molded product can take a large area of the joint interface between the first foamed resin material and the second foamed resin material by this raised ridge, and can increase the strength of the joint interface.

FIG. 1 is a cross-sectional view of a foamed resin molding die according to an embodiment of the present invention, showing a state before filling with foamed resin particles. FIG. 2 is a cross-sectional view of the foamed resin molding die showing a state in which foamed resin particles are filled. FIG. 3 is a cross-sectional view of the foamed resin molding die showing a state where the shutter is opened. FIG. 4 is a cross-sectional view of the foamed resin molding die, showing a state where the movable die is separated from the fixed die. FIG. 5 is an enlarged perspective view showing a main part of the different foamed resin molded product of the present invention. 6 is a cross-sectional view taken along line AA in FIG.

  FIG. 1 is a plan sectional view of a foamed resin mold (10) showing an embodiment of the present invention. As shown in the figure, the foamed resin molding die (10) is composed of a fixed mold (20) and a movable mold (30), and between the fixed mold (20) and the movable mold (30), a foamed resin material ( A cavity (12) filled with 50) and (60) is formed.

  The foamed resin molding die (10) described in the present embodiment is for molding a bumper core material of an automobile, and is configured such that the fixed die (20) is a concave die and the movable die (30) is a convex die. Yes. More specifically, as shown in FIGS. 5 and 6 to be described later, the dissimilar foamed resin molded product (80) produced according to the present example is a fixed mold (which is a concave mold in the outer periphery (81) (82) ( The 20) side is configured to be a mounting surface (83) to be mounted on the automobile frame.

  A steam chamber in which heated steam is introduced around the foamed resin mold (10) to heat the fixed mold (20) and the movable mold (30) to fuse the foamed resin material in the cavity (12). (14) is formed.

The movable mold (30) can be moved toward and away from the fixed mold (20) by a slide mechanism (not shown).
In addition, a slit (21) is formed in the fixed mold (20), and a shutter (40) that can be projected and retracted toward the movable mold (30) passes through the slit (21). One end of the shutter (40) is connected to an opening / closing mechanism (42) composed of a cylinder or the like, and the shutter (40) is fixed to the fixed type (20) by the operation of the opening / closing mechanism (42), that is, expansion and contraction of the cylinder. It is possible to partition the cavity (12) by intruding toward the movable mold (30).

  The shutter (40) is formed to have an outer shape and dimensions that are slidably fitted into a side groove (22) and a bottom groove (32) that are recessed in the fixed mold (20) and the movable mold (30) described below.

On the inner surface of the fixed mold (20), a side groove (22) is provided continuously with the slit (21) so that the side portion of the shutter (40) can be slidably fitted therein.
The width W of the side groove (22) is set to be equal to or larger than the particle diameter of the first foamed resin particle (50) so that the first foamed resin particle (50) described later can enter the side groove (22). Is preferred. More desirably, it is 1 to about 3 times the particle size of the first foamed resin particles (50). Note that at least the thickness t of the shutter (40) is set to be equal to or greater than t, and the width W is set to the thickness t + 0.2 to 0.4 mm of the shutter (40) in order to smoothly slide the shutter (40).

  In addition, a bottom groove (32) into which the tip of the shutter (40) is fitted is recessed in the inner surface of the movable mold (30) at the tip of the slide transition path of the shutter (40). The bottom groove (32) can be formed to be continuous with the side groove (22) of the movable mold (20) when the movable mold (30) is moved in the closing direction with respect to the fixed mold (20).

  The width W ′ of the bottom groove (32) is the same as the width W of the side groove (22) of the fixed mold (20) so that the first foamed resin particles (50) can enter the side groove (22). The width is preferably equal to or larger than the particle diameter of the first foamed resin particles (50). More desirably, it is 1 to about 3 times the particle size of the first foamed resin particles (50). Note that at least the thickness t of the shutter (40) is set to be equal to or larger than the thickness t, and the width W ′ is set to the thickness t + 0.2 to 0.4 mm of the shutter (40) in order to smoothly slide the shutter (40).

  By sliding the shutter (40) toward the movable mold (30), the cavity (12) is divided into two spaces. Here, among the divided spaces, the left space in the figure is referred to as a first cavity (24), and the right space is referred to as a second cavity (27).

  The fixed mold (20) is provided with raw material filling holes (25) and (28) communicating with the first cavity (24) and the second cavity (27), respectively, and the raw material filling holes (25) (28) ) Are each connected to a raw material feeder (not shown).

  In the foamed resin molding die (10) having the above-described configuration, with the movable die (30) engaged with the fixed die (20), the opening / closing mechanism (42) is operated as shown in FIG. Slide 40) in the direction of the movable mold (30). As a result, the side of the shutter (40) is fitted into the side groove (22) of the fixed mold (20), and the tip is fitted into the bottom groove (32) of the movable mold (30).

  As described above, the cavity (12) is divided into the first cavity (24) and the second cavity (27) by the shutter (40), and as shown in FIG. The foamed resin material (50) and the second cavity (27) are filled with the second foamed resin material (60).

The first foamed resin material (50) and the second foamed resin material (60) can be filled in the cavities (24) and (27) in the form of foamed resin particles, respectively.
The foamed resin particles are obtained by pre-foaming synthetic resin particles containing a foaming agent. The synthetic resin constituting the synthetic resin particles may be any foamed resin, but is preferably a thermoplastic resin foamed resin. Thermoplastic resins include polystyrene resins, polyolefin resins (eg, polypropylene resins, polyethylene resins), polyester resins (eg, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate), polycarbonate resins, polylactic acid resins, etc. Is mentioned. Among these, it is preferable to use a composite resin containing polystyrene and polyethylene.

As the first foamed resin material (50) and the second foamed resin material (60), different foaming resin materials, that is, different foamed resin materials are selected. In the present embodiment, the first foamed resin material (50) will be described as a foamed resin material having a lower foaming ratio than the second foamed resin material (60).
In this case, the desirable expansion ratio of the first foamed resin material (50) is 5 to 50 times, and the desirable expansion ratio of the second foamed resin material (60) is 10 to 90 times.

  Particles of the first foamed resin material (50) (hereinafter also referred to as “first foamed resin particles (50)”) are particles of the second foamed resin material (60) (hereinafter referred to as “second foamed resin particles (60)”). It is desirable to have a smaller particle size. Desirable particle diameters of the foamed resin particles are 1.5 to 6.5 mm for the first foamed resin material (50) and 2.5 to 15 mm for the second foamed resin material (60).

  As shown in FIG. 2, the first foamed resin particles (50) are filled into the first cavities (24) from the raw material filling holes (25) on the first cavity (24) side, and the second foamed resin particles (60) are filled. Is filled into the second cavity (27) from the raw material filling hole (28) on the second cavity (27) side.

  The first foamed resin particles (50) and the second foamed resin particles (60) that have been charged are sequentially stacked from the bottom of the cavities (24) and (27) by gravity.

  As shown in FIG. 2, when the first foamed resin particles (50) and the second foamed resin particles (60) are sufficiently filled in the cavities (24) and (27), the supply of the raw materials is stopped and the raw material is filled. The holes (25) and (28) are closed and the opening / closing mechanism (42) is operated to open the shutter (40) as shown in FIG.

  When the shutter (40) is opened, the first foamed resin particles (50) having a small particle size enter the side groove (22) of the fixed mold (20), and as shown in FIG. 3, the bottom of the movable mold (30) The first foamed resin particles (50) also enter the groove (32).

  In this state, when heated steam is introduced into the steam chamber (14) and the foamed resin particles (50) and (60) are heated, these particles soften and expand, and enter the bonding interface (85) (see FIG. 6). Are joined together. At this time, the first foamed resin particles (50) that have entered the side groove (22) and the bottom groove (32) expand along the shape of the side groove (22) and the bottom groove (32).

  After the heating, the cavity (12) is cooled and the slide mechanism is operated to move the movable mold (30) away from the fixed mold (20) as shown in FIG. Take out.

  FIG. 5 is a partially enlarged perspective view of the molded different-shaped foamed resin molded product (80), and the surface visible on the upper side is the movable mold (30) side. 6 is a cross-sectional view taken along the line AA in FIG. 5, and similarly, the upper side is the movable mold (30) side.

  As shown in FIG. 5, in the different foamed resin molded product (80) of the present invention, the first foamed resin material (50) protrudes along the shape of the side groove (22) and the bottom groove (32), and the ridge (84) ) Is formed. As shown in FIG. 6, the ridges (84) are formed so as to protrude from the outer periphery (81) of the joint interface (85) between the first foamed resin material (50) and the second foamed resin material (60). .

  In this embodiment, as shown in FIG. 5 and FIG. 6, the raised ridge (84) protruding from the outer periphery (81) of the dissimilar foamed resin molded product (80) has an attachment surface (83) to the frame of the automobile. It is formed on three surfaces other than the outer periphery (82). This is because if the raised ridge (84) is formed on the mounting surface (83), it causes backlash and the like.

  The ridges (84) formed by filling the first foamed resin material (50) into the side grooves (22) and the bottom groove (32) are formed on the second foamed resin material (60) side as shown in FIG. It is formed to cover. Therefore, the area of the joining interface (85) between the first foamed resin material (50) and the second foamed resin material (60) is increased, and the joining strength of the joining interface (85) is increased as much as possible. it can.

  When two or more outer peripheral surfaces of the joint interface (85) of the dissimilar foamed resin molded product (80) are the mounting surfaces (83), the corresponding mounting surface (83) is not provided with the ridges (84). It can also be configured. In addition, when the outer periphery (81) (82) of the joining interface (85) does not become the mounting surface (83), it is desirable to provide a ridge (84) on the entire outer periphery of the joining interface (85).

  As described above, the foamed resin molding die (10) of the present invention has a raised strip (84) that can increase the joint strength of the joint interface (84) of the different foamed resin molded product (80) as much as possible. Can be formed.

  In addition, as described above, the dissimilar foamed resin molded product (80) of the present invention has the ridge (84) on the outer periphery (81) of the joining interface (85), thereby increasing the area of the joining interface (85). The bonding strength can be increased as much as possible.

  INDUSTRIAL APPLICABILITY The present invention is useful as a foamed resin molding die and a different type of foamed resin molded product that can increase the joint strength at the joint interface between different kinds of foamed resin materials.

(10) Foamed resin mold
(12) Cavity
(20) Fixed type
(22) Side groove
(30) Movable type
(32) Bottom groove
(40) Shutter
(50) First foamed resin material (particles)
(60) Second foamed resin material (particles)
(80) Different types of foamed resin molded products
(84) Uplift
(85) Bonding interface

Claims (7)

A cavity formed by a fixed mold and a movable mold;
Provided with a shutter that slidably moves from the fixed mold side to the movable mold to partition the cavity,
By filling the first cavity and the second cavity partitioned by the shutter with the first foamed resin particles and the second foamed resin particles made of foamed resin materials having different foaming ratios, respectively, and by opening the shutter and heating it. A foamed resin molding die for continuously molding foamed resins having different foaming ratios,
A side groove recessed in the inner surface of the fixed mold and into which a side portion of the shutter is fitted;
A bottom groove recessed in the inner surface of the movable mold, into which the tip of the shutter fits,
Have
The side groove and the bottom groove are widths into which any foamed resin material enters when heated by sliding the shutter open.
A foamed resin molding die characterized by that. The first foamed resin particles have a smaller particle size than the second foamed resin particles,
2. The foamed resin molding die according to claim 1, wherein the side groove and the bottom groove have a width that allows the first foamed resin particles to enter when the shutter is opened. The first foamed resin particles are a foamed resin material having a lower expansion ratio than the second foamed resin particles,
The foamed resin molding die according to claim 1 or 2, wherein the side groove and the bottom groove have a width that allows the first foamed resin particles to enter when the shutter is opened. A different type of foamed resin molded product obtained by continuously molding a first foamed resin material and a second foamed resin material having different foaming ratios,
The joint interface between the first foamed resin material and the second foamed resin material is a dissimilar foamed resin molded product characterized in that a ridge that protrudes from the first foamed resin material is formed on the outer periphery.   The dissimilar foamed resin molded product according to claim 4, wherein the raised ridge is not formed on an attachment surface to an article.   The different-type foamed resin molded product according to claim 4 or 5, wherein the first foamed resin material is obtained by foam-molding foamed resin particles having a smaller particle diameter than the second foamed resin material.   The said 1st foamed resin material is a different foamed resin molded product in any one of Claims 4 thru | or 6 which is a foamed resin material of a low foaming ratio than a 2nd foamed resin material.

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