JP5192407B2 - Mold for molding and molded product molded using the mold - Google Patents

Description

  The present invention relates to a mold for molding, specifically, a mold for molding using pre-expanded beads, and a molded product molded using the mold.

FIG. 6 is a cross-sectional view of a molding die that is molded using conventional pre-expanded beads, and FIG. 7 is an enlarged view of a portion B in FIG. 6 (see Patent Document 1). As is well known, the mold (4) is configured by providing a fixed mold (40) and a movable mold (5) so as to be close to and away from each other, and pre-foamed in a molding space (41) between the molds (40) and (5). The molded product (3) is formed by filling the beads from the filling cylinder (60). Both molds (40) and (5) are each formed with a heating space (42), and when the heating space (42) is filled with heating steam, the pre-expanded beads in the molding space (41) are foamed and fused. After cooling, the molded product (3) is formed.
The fixed die (40) is provided with an eject pin (6) protruding from the molding space (41) so as to protrude from the molding space (41), and in the vicinity of the ejection pin (6), the molded product (3 ) Is provided on the fixed die (40) with an undercut pin (2). The head (20) of the undercut pin (2) is formed in a taper shape so as to expand toward the movable mold (5) and is disposed in the molding space (41). (20) engages with the molded product (3) and leaves the molded product (3) on the stationary mold (40). The molded product (3) left on the fixed mold (40) is pushed out by the eject pin (6) against the engagement with the head (20). The filling cylinder (60) and the eject pin (6) may be provided in the movable mold (5) instead of the fixed mold (40).
In the molded product (3) after molding, as shown in FIG. 8, a recess (31) which is a trace of the head (20) of the undercut pin (2) is formed. There has also been proposed a sound absorbing material that uses the recess (31) as a sound absorbing hole (see Patent Document 2).

JP 2001-79869 A JP 2003-340858 A

The concave portion (31) on the molded product (3) has a role as a sound absorbing hole. However, when the molded product (3) is used for purposes other than as a sound absorbing material, the excessive concave portion (31) is formed on the molded product (3 ) Will be established on the surface. In this case, since the unnecessary recess (31) is opened in the molded product (3), the appearance of the molded product (3) is poor. Further, when the molded product (3) is transported, if the concave portion (31) is caught by other objects and there are many concave portions (31), it has been a cause of causing scratches, tears and cracks on the molded product (3).
In view of solving this problem, the applicant has conceived the following device. On the molded product (3), information such as the material, application, and specifications of the molded product (3) is usually displayed. This display is generally expressed at the time of molding by attaching a plate material as a name plate to the surface of the fixed mold (40) or the movable mold (5) on the molding space (41) side. It was conceived that the concave portion (31) was recessed from the surface of the molded product (3) by using the attachment of the nameplate to the mold (4).
An object of the present invention is to eliminate an excessive concave portion from the surface of a molded article and to improve the releasability.

  The mold (4) includes a fixed mold (40) and a movable mold (5) that forms a molding space (41) in combination with the fixed mold (40). On either mold, the plate material (1) is provided. The plate (1) is mounted on the mold by an undercut pin (2) having a head (20) disposed in a molding space (41). The head (20) is formed in a tapered shape that expands toward the opposing mold. Further, the peripheral surface (10) of the plate material (1) is formed in a taper shape that expands toward the die facing the die to which the plate material (1) is attached.

1. The plate (1) is mounted on any of the molds with an undercut pin (2) whose head (20) is arranged in the molding space (41). The head (20) is located inside the peripheral edge of the plate (1). When the molded product (3) is molded with the mold (4), the concave portion (31) is further formed inside the concave surface (30) which is a trace of the plate material (1). That is, since the concave portion (31) is recessed from the surface of the molded product (3), the excessive concave portion (31) does not appear on the molded product (3) as in the prior art, and the appearance of the molded product (3) is improved. Can be improved.
In addition, it is possible to eliminate the possibility that the concave portion (31) is caught by another object during transportation of the molded product (3), causing scratches, tears and cracks on the molded product (3).
2. The plate (1), specifically the screw that fastens the nameplate to the mold, is used together with the undercut pin (2), and the plate (1) and the molded product (3) are held on the undercut pin (2). By having it, workability at the time of mounting the plate material (1) can be improved.
3. By forming the peripheral surface (10) of the plate material (1) in a tapered shape, the undercut effect of leaving the molded product (3) in the mold can be further enhanced.

It is a top view of the molded product shape | molded using the metal mold | die concerning this example. It is sectional drawing which fractured | ruptured the molded article of FIG. 1 in the vertical surface containing an AA line. It is sectional drawing of the metal mold | die which shape | molds a molded article. It is the figure which expanded the C section of FIG. It is sectional drawing which shows the metal mold | die after mold release. It is sectional drawing of the conventional metal mold | die. It is an enlarged view of the B section of FIG. It is sectional drawing of the conventional molded article.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a plan view of a molded product (3) molded using the mold (4) according to this example, and FIG. 2 is a vertical view including the AA line of the molded product (3) of FIG. It is sectional drawing fractured | ruptured in the surface. The molded product (3) is an automobile interior member such as a raising material, and is formed from a foamed resin. The molded product (3) is formed by filling pre-expanded beads in a molding space of a mold and heating, and specific examples of the foamed resin will be described later. Concave surface (30) (30a) is formed on the surface of molded product (3), and display (32) of information on material, application, specifications, etc. of molded product (3) is raised in one concave surface (30). Shown. In FIG. 1, the indication (32) in the concave surface (30) indicates the material of the molded product (3). As shown in FIG. 2, a concave portion (31) is further formed in the concave surface (30), and the concave surface (30) is a plate material (1) described later, specifically, a molding mark of the nameplate, The concave portion (31) is a forming mark of the head portion (20) of the undercut pin (2).
Moreover, as shown in FIG. 1, the round circle (34) which is the trace of the eject pin (6) remains on the surface of the molded product (3).

FIG. 3 is a cross-sectional view of the mold (4) for molding the molded product (3). As in the prior art, the fixed mold (40) and the movable mold (5) are combined to form both molds (40) (5). A molding space (41) is formed between them. The movable pin (5) is provided with an eject pin (6) and a filling cylinder (60). FIG. 4 is an enlarged view of a portion C in FIG.
On the surface of the movable mold (5) on the side of the molding space (41), a plate material (1) which is a name plate (also called a take-in) is provided, and a dent (11) is provided on the surface of the plate material (1). Yes. The recess (11) is filled with foamed resin, and the display (32) is raised in the recess (30).
The plate material (1) is mounted on the movable die (5) with an undercut pin (2). That is, the undercut pin (2) is located inside the peripheral edge of the plate material (1). The undercut pin (2) penetrates through the plate (1) and is screwed into the movable mold (5) (21) and a head formed in a tapered shape so as to spread toward the fixed mold (40). Has part (20).
In this example, the undercut pin (2) is provided on the movable die (5), but it may be provided on the fixed die (40). Further, the peripheral surface (10) of the plate material (1) is formed in a taper shape extending toward the fixed mold (40).

FIG. 5 is a cross-sectional view showing the mold (4) after mold release. Since the head (20) is located in the molding space (41), it is buried in the molded product (3). Since the head portion (20) is tapered so as to expand toward the fixed die (40), the molded product (3) is left in the movable die (5) at the time of releasing from the head portion (20). Undercut effect. Further, since the peripheral surface (10) of the plate (1) is also formed in a taper shape that expands toward the fixed mold (40), there is an undercut effect. Therefore, after the mold release, the molded product (3) is left in the movable mold (5).
That is, in this example, the molded product (3) is moved to the movable die (5) at the time of mold release by the head (20) of the undercut pin (2) and the peripheral surface (10) of the plate (1). The undercut effect that is left behind is obtained and the undercut effect is strengthened.
Also, the screw (21) that fastens the plate (1) to the movable die (5) is used together with the undercut pin (2), and the plate (1) and the molded product (3) are held on the undercut pin (2). By giving the function to perform, workability at the time of mounting the plate material (1) can be improved. Furthermore, since the screw (21) for fastening the plate material (1) to the movable mold (5) is used in combination with the undercut pin (2), no extra recess (31) is formed.

After release, the molded product (3) is extruded against the head (20) and the peripheral surface (10) of the plate (1) with the eject pin (6), and the molded product (3) shown in FIG. obtain. Since the head (20) is located on the inner side of the periphery of the plate material (1), the molded product (3) after molding is further provided on the inner side of the concave surface (30) which is a trace of the plate material (1). A recess (31) is formed in the recess.
That is, since the concave portion (31) is recessed from the surface of the molded product (3), the concave portion (31) is caught by another object during the transportation of the molded product (3) as in the prior art, and the molded product (3). The possibility of causing scratches, tears and cracks on the top can be eliminated. Since the recess (31) is a molding mark of the head (20), it is formed in a tapered shape so as to become narrower toward the movable mold (5) to be left.
Similarly, the peripheral surface (33) of the concave surface (30) is also tapered so as to become narrower toward the movable mold (5) to be left.
Since the concave surface (30) is exposed on the surface of the molded product (3), it is considered that the concave surface (30) is caught by other objects, and the molded product (3) is scratched, torn or cracked. However, since the concave surface (30) has a smaller number and a larger area than the concave portion (31), it is considered that there is less possibility of the concave surface (30) being caught.

  Foam resins used for molding include polystyrene resins, polyolefin resins (for example, polypropylene resins, polyethylene resins), polyester resins (for example, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate), polycarbonate resins, polylactic acid Based resins and the like. Among these, it is preferable to use a composite resin of polystyrene and polyethylene.

The above description of the embodiments is for explaining the present invention, and should not be construed as limiting the invention described in the claims or reducing the scope thereof. In addition, the configuration of each part of the present invention is not limited to the above embodiment, and various modifications can be made within the technical scope described in the claims.
For example, any mold is provided with a convex portion (not shown) protruding into the molding space (41), and the head (20) is provided in the convex space in the molding space (41). (2) may be attached.
The plate (1) is attached to the movable die (5) by the screw (21) of the undercut pin (2). For example, the plate (1) is attached to the movable die (5) by welding or the like. An undercut pin (2) may be attached on the plate material (1), and the head (20) may be disposed in the molding space (41).
The technical idea of the present invention can also be applied to an injection mold.

(1) Board material
(2) Undercut pin
(3) Molded products
(4) Mold
(5) Movable type
(40) Fixed type
(41) Molding space

Claims (8)

An undercut pin having a fixed mold and a movable mold that forms a molding space in combination with the fixed mold, on which a plate material is disposed, and a head is disposed on the plate material in the molding space. A mold characterized by being attached. The metal mold according to claim 1, wherein the plate material is attached onto the mold by an undercut pin. 3. The mold according to claim 1, wherein a peripheral surface of the plate material is formed in a tapered shape that expands toward a die facing the die to which the plate material is attached. The mold according to any one of claims 1 to 3, wherein the plate material is a nameplate indicating information on a molded product to be molded. A fixed mold and a movable mold that forms a molding space in combination with the fixed mold, and any of the molds has a convex portion protruding into the molding space, and the head has a molding space in the convex portion. Mold with an undercut pin installed inside. The die according to any one of claims 1 to 5, wherein the head portion of the undercut pin is formed in a tapered shape that expands toward an opposing die. A fixed mold and a movable mold are formed by a mold provided so as to be able to approach and separate, a concave surface is formed on the surface, a concave portion is formed in the concave surface, and the concave portion is tapered toward a mold to be left at the time of molding. A molded product characterized by being formed into a shape. The molded product according to claim 7, wherein the concave peripheral surface is formed in a tapered shape that becomes narrower toward a mold to be left at the time of molding.

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