JP6920948B2 - Molding method for mold equipment and resin molded products - Google Patents

Description

The present invention relates to a mold device for molding a resin molded product in which a ridge portion of the first molded product is exposed from the design surface of the second molded product, and a molding method for the resin molded product.

For example, for the purpose of improving the design of vehicle interior members used in automobiles and the like, resin molded products that reproduce stitch patterns such as thread seams have been proposed.

As shown in FIG. 9, the resin molded product having a stitch pattern has a first molded body 112 that constitutes a main part of the design surface and a protrusion that is exposed from the design surface of the first molded body 112 to form a stitch pattern. It is composed of a second molded body 110 provided with a strip 110a (see Patent Document 1). Further, in this type of resin molded product, first, either one of the first molded product and the second molded product is molded first by filling the mold with a resin material, and then the molded product is made of gold. It is generally molded by a so-called two-color molding method in which another resin material is filled while remaining in the mold and the other is molded.

Japanese Unexamined Patent Publication No. 2012-139966

In two-color molding of a resin molded product having a stitch pattern as described above, for example, if a mold device as shown in FIG. 10 is used, it is possible to perform two-color molding with the same mold without changing the mold. Is. Specifically, this mold apparatus includes an upper mold 200 for molding the design surface side of the resin molded product and a lower mold 300 for molding the back surface side of the resin molded product, and the upper mold 200 is first molded. A design molding surface 200a for molding the design surface of the body and a recess 200b for molding the stitch pattern (protruding portion) of the second molded body are formed. On the other hand, the lower mold 300 is formed with a convex portion 300a for sealing the concave portion 200b of the upper mold 200.

In order to mold a resin molded product using this mold device, first, as shown in FIG. 10 (A), a first mold for molding a first molded product between the upper mold 200 and the lower mold 300. One cavity 400 is defined. Then, as shown in FIG. 10B, the first resin material 500 is filled in the first cavity 400 to form the first molded product. At this time, since the concave portion 200b of the upper mold 200 is sealed by the convex portion 300a of the lower mold 300, the intrusion of the first resin material 500 into the concave portion 200b is prevented. After that, as shown in FIG. 10C, by separating the lower mold 300 from the upper mold 200, the recess 200b is opened and the second cavity 600 for molding the second molded body is defined. do. Then, as shown in FIG. 10D, by filling the second cavity 600 with the second resin material 700, a second molded body having a ridge portion is formed. After that, by releasing the mold, a resin molded product in which the first molded body and the second molded body are integrated can be obtained.

By the way, in the mold apparatus shown in FIG. 10, in order to seal the concave portion 200b, the convex portion 300a is brought into contact with the entire inner surface of the concave portion 200b. On the other hand, the configuration in which the convex portion 300a is brought into contact with the seal is required to have high accuracy in terms of the dimensions and positioning of the concave portion 200b and the convex portion 300a. That is, if a slight dimensional error or misalignment occurs in the concave portion 200b or the convex portion 300a, a gap is generated between the concave portion 200b and the convex portion 300a. There is a possibility of entering the recess 200b. As described above, in the mold apparatus shown in FIG. 10, it was difficult to reliably seal the recess 200b.

Therefore, an object of the present invention is to ensure that the molds are in close contact with each other and that material leakage can be reliably prevented without manufacturing or positioning the molds with high accuracy.

In order to solve the above problems, the present invention comprises a first molded body in which a plurality of ridges and the ridges are connected to each other and a connecting portion having a width smaller than the width of the ridges is provided, and a design. A mold device for molding a resin molded product having a second molded body in which the ridge portion is exposed from the surface, the first molding mold for molding the design surface side of the resin molded product, and the resin. The back surface side of the molded product is molded, and a first cavity for molding the first molded product and a second cavity for molding the second molded product are defined between the molded product and the first molding mold. A pair of a second molding die, the first molding die, a recess for forming the ridge portion, a flat surface portion for forming the connecting portion, and a pair provided on both sides of the recess and the flat surface portion. of an inclined surface portion, said second mold, wherein a first mold the recess and the flat surface portion facing the recess, the pair of inclined surface portions facing the pair of inclined surface portions of the first mold And the pair of flat surface portions of the second molding die, which face the flat surface portion of the first molding die and are provided between the concave portion of the second molding die and the pair of inclined surface portions. The inclined surface portion and the pair of flat surface portions are in contact with the pair of inclined surface portions and the flat surface portion of the first molding die and communicate with the recesses of the first molding die and the second molding die, respectively. Provided is a mold device that functions as a partition portion for partitioning and defining a first cavity from a peripheral region thereof.

In this way, the pair of inclined surface portions and the pair of flat surface portions of the second molding die come into contact with the pair of inclined surface portions and the flat surface portions of the first molding die, so that the entire inner surface of the recess as in the example shown in FIG. Compared with the configuration in which the convex portion is brought into contact with the mold, the molds can be reliably brought into close contact with each other without manufacturing or positioning the molds with high accuracy. As a result, the first cavity and the peripheral region thereof can be reliably separated.

Further, in order to solve the above problems, the present invention relates to a first molded product in which a plurality of ridges and the ridges are connected to each other and a connecting portion having a width smaller than the width of the ridges is provided. , a molding method for molding the resin molded article and a second molded body is exposed the protrusions from the design surface, and a recess for forming the front Symbol ridges, and a flat surface portion forming said connecting portion A first molding die provided with the recess and a pair of inclined surface portions provided on both sides of the flat surface portion to mold the design surface side of the resin molded product, the recess of the first molding die, and the recess. A recess facing the flat surface portion, a pair of inclined surface portions facing the pair of inclined surface portions of the first molding mold, the recess facing the flat surface portion of the first molding mold, and the recess of the second molding mold and the said. a pair of flat surface portions disposed between the pair of inclined surface portions are provided, and a second mold for molding the rear surface side of the resin molded article, by relatively close, the pair of the second mold By bringing the inclined surface portion and the pair of flat surface portions of the first molding mold into contact with the pair of inclined surface portions and the flat surface portion of the first molding mold, the two recesses of the first molding mold and the second molding mold are communicated with each other. A step of partitioning the first cavity from its peripheral region and defining it, a step of filling the first cavity with a first resin material to form the first molded body, and a step of forming the first molded body into the first cavity. The step of defining the second cavity by relatively separating the first molding die and the second molding die while leaving the second cavity, and the step of filling the second cavity with the second resin material to form the second cavity. (Ii) Provided is a method for molding a resin molded product, which comprises a step of molding a molded product.

In this way, by bringing the pair of inclined surface portions and the pair of flat surface portions of the second molding die into contact with the pair of inclined surface portions and the flat surface portions of the first molding die, the entire inner surface of the recess as in the example shown in FIG. Compared to the configuration in which the convex portions are brought into contact with each other, the molds can be reliably brought into close contact with each other without manufacturing or positioning the molds with high accuracy. As a result, the first cavity and the peripheral region thereof can be reliably separated.

According to the present invention, even if the molds are not manufactured or positioned with high accuracy, the molds can be surely brought into close contact with each other to prevent the resin material from leaking. Shape accuracy and design can be ensured, and quality is improved. In addition, it becomes easy to manage the dimensions and positioning of the mold.

It is a perspective view of the panel which concerns on one Embodiment of this invention. It is a figure which shows the cross-sectional shape of each part of the panel shown in FIG. 1, (A) is the cross-sectional view of AA of FIG. It is sectional drawing of the mold apparatus for molding a panel shown in FIG. 1, (A) is the sectional view of the part corresponding to FIG. 2 (A), (B) corresponds to FIG. 2 (B). It is sectional drawing of the part. It is a figure for demonstrating the molding method of the panel shown in FIG. It is a figure for demonstrating the molding method of the panel shown in FIG. It is a figure for demonstrating the molding method of the panel shown in FIG. It is a figure for demonstrating the molding method of the panel shown in FIG. It is sectional drawing of the mold apparatus which concerns on other embodiment of this invention. It is a figure which shows an example of the resin molded article which formed the stitch pattern. (A) to (D) are cross-sectional views of the mold apparatus according to the comparative example.

Hereinafter, the molding method of the mold device and the resin molded product according to the embodiment of the present invention will be described by taking as an example the case of molding an instrument panel installed in the front part of the vehicle interior of an automobile or the like. However, the mold apparatus and molding method according to the present invention are not limited to the case of molding an instrument panel. For example, the present invention can be applied to other vehicle interior members such as door trims and console boxes, as well as resin molded products used other than vehicles.

FIG. 1 is a perspective view of an instrument panel (hereinafter, simply referred to as “panel”) according to the present embodiment, FIG. 2 is a view showing a cross-sectional shape of each part of the panel shown in FIG. A cross-sectional view taken along the line 1A and FIG. 1B is a cross-sectional view taken along the line BB of FIG.

As shown in FIGS. 1 and 2, the panel 1 is composed of a first molded body 2 and a second molded body 3 molded of resin materials of different colors. In FIG. 1, the front side of the panel 1 is the design surface. A plurality of ridges 2a are intermittently provided in the first molded body 2, and these ridges 2a are exposed from the design surface of the second molded body 3, so that the second molded body 3 A stitch pattern that looks like it is sewn with thread is constructed on the design surface of. In the present embodiment, the plurality of ridge portions 2a are arranged along the groove portions 3a formed on the design surface of the second molded body 3.

Further, the plurality of ridge portions 2a are connected to each other via a connecting portion 2b arranged between them. In each connecting portion 2b, a part of the flat surface of the first molded body 2 is exposed from the design surface of the second molded body 3, does not protrude from the groove portion 3a of the second molded body 3, and the bottom of the groove portion 3a. {See FIG. 2 (B)}.

In this way, the reason why the plurality of ridges 2a are connected via the connecting portion 2b is that the plurality of ridges can be formed from one gate by the resin material filled in the mold. Because. However, from the viewpoint of the design of the stitch pattern, it is preferable that the connecting portion 2b is not so conspicuous. Therefore, in the present embodiment, the width Wb of the connecting portion 2b is made smaller than the width Wa of the ridge portion 2a to make it less noticeable. The stitch pattern may be formed by directly connecting the ends of the ridges 2a without providing the connecting portion 2b.

FIG. 3 is a cross-sectional view of a mold device for molding a panel according to the present embodiment.
Each cross section of the mold apparatus shown in FIGS. 3A and 3B corresponds to each cross section of the panel shown in FIGS. 2A and 2B.

As shown in FIG. 3, the mold apparatus 4 includes an upper mold 5 as a first molding mold for molding the design surface side of the panel and a lower mold 6 as a second molding mold for molding the back surface side of the panel. Be prepared.

The upper mold 5 includes a design forming surface 5a for forming the main portion of the design surface, a pair of inclined surface portions 5b for forming both side surfaces of the groove portion 3a, and a flat surface portion 5c for forming the bottom portion of the groove portion 3a and the connecting portion 2b. It has a recess 5d for forming the ridge portion 2a. The pair of inclined surface portions 5b are inclined so as to approach each other downward. The flat surface portion 5c and the recess 5d are arranged between the pair of inclined surface portions 5b, and are provided so as to be continuous from the end portions of the inclined surface portions 5b. Further, the inner surface of the recess 5d is inclined so as to spread from the bottom 5d1 toward the opening edge 5d2.

The lower mold 6 has a main mold 7 and a slide mold 8 slidably provided with respect to the main mold 7. The slide mold 8 is configured to approach and separate from the upper mold 8 by sliding and moving in the vertical direction. On the upper surface of the slide mold 8, a pair of inclined surface portions 8b facing the pair of inclined surface portions 5b of the upper mold 5 are provided. The pair of inclined surface portions 8b of the slide type 8 are inclined so as to be separated from each other upward, and are formed in the same shape as the inclined surface portions 5b of the upper mold 5 (curved surface shape in the present embodiment). Further, the slide type 8 is provided with a recess 8a between the inclined surface portions 8b. The recess 8a is formed so as to have a width smaller than that of the other portion at the portion {the portion shown in FIG. 3 (B)} corresponding to the cross section of the connecting portion 2b. Further, in a place where the width of the recess 8a is small, a flat surface portion 8c substantially orthogonal to the slide direction of the slide type 8 is provided between the recess 8a and the pair of inclined surface portions 8b. The flat surface portion 8c is arranged so as to face and parallel to the flat surface portion 5c of the upper die 5.

As shown by the alternate long and short dash line in FIG. 3, when the slide mold 8 is raised and approaches the upper mold 5, the pair of inclined surface portions 8b of the slide mold 8 are in contact with the pair of inclined surface portions 5b of the upper mold 5. Placed in. Further, at the portion corresponding to the cross section of the connecting portion 2b {the portion shown in FIG. 3B}, the flat surface portion 8c of the slide mold 8 is also arranged in contact with the flat surface portion 5c of the upper mold 5.

In this way, when the slide type 8 is raised and the inclined surface portion 8b and the flat surface portion 8c of the slide type 8 are in contact with the inclined surface portion 5b and the flat surface portion 5c of the upper mold 5, the slide type 8 is brought into contact with each other. The inner region and the outer region of the are separated. That is, the inclined surface portion 8b and the flat surface portion 8c of the slide mold 8 function as a partition portion 10 that partitions the inner region and the outer region of the slide mold 8 by contact with the inclined surface portion 5b and the flat surface portion 5c of the upper mold 5.

Subsequently, a method of molding a panel using the mold apparatus of the present embodiment will be described with reference to FIGS. 4 to 7.

First, as shown in FIG. 4, the upper mold 5 and the lower mold 6 are molded, and the upper mold 5 and the lower mold 6 are brought into contact with each other. Further, in this state, the slide mold 8 is arranged at a position close to the upper mold 5, so that the inclined surface portion 8b and the flat surface portion 8c (partition portion 10) of the slide mold 8 are arranged in the inclined surface portion 5b of the upper mold 5. And contacts the flat surface portion 5c. As a result, the inner region and the outer region of the slide mold 8 are partitioned, and the first cavity 11 in which the recess 8a of the slide mold 8 and the recess 5d of the upper mold 5 communicate with each other is defined.

Then, as shown in FIG. 5, the first cavity 11 is filled with the first resin material softened by heating while applying pressure by an injection molding machine. At this time, the inclined surface portion 8b and the flat surface portion 8c (partition portion 10) of the slide mold 8 are in contact with the inclined surface portion 5b and the flat surface portion 5c of the upper mold 5, so that the first cavity 11 is outward. (1) Leakage of resin material is prevented. After that, the first resin material is cooled and cured to form the first molded body 2 having the plurality of ridges 2a.

Next, as shown in FIG. 6, the slide mold 8 is lowered while the first molded body 2 is left in the first cavity 11, and the slide mold 8 is separated from the upper mold 5. As a result, the contact between the inclined surface portion 8b and the flat surface portion 8c (partition portion 10) of the slide mold 8 and the inclined surface portion 5b and the flat surface portion 5c of the upper mold 5 is released. As a result, the second cavity 12 is defined by the region generated by lowering the slide mold 8 and the peripheral region thereof.

Then, as shown in FIG. 7, the second cavity 12 is filled with the second resin material softened by heating while applying pressure by an injection molding machine. At this time, the intrusion of the second resin material into the recess 8a of the slide mold 8 is blocked by the first molded body 2 formed earlier. That is, since the side surface of the first molded body 2 and the side surface of the recess 8a are in contact with each other, the recess 8a is sealed so that the second resin material does not invade. After that, the second resin material is cooled and cured to form the second molded body 3. Then, by opening the upper mold 5 and the lower mold 6 and releasing the resin molded product, a panel in which the first molded body 2 and the second molded body 3 are integrated can be obtained.

As described above, in the molding method according to the present embodiment, in order to partition the first cavity and the peripheral region thereof, the inclined surface portion 8b and the flat surface portion 8c of the slide mold 8 are replaced with the inclined surface portion 5b and the flat surface portion of the upper mold 5. It is in contact with 5c (see FIG. 4). That is, in the present embodiment, unlike the configuration in which the convex portion is brought into contact with the entire inner surface of the concave portion as shown in FIG. 10 to prevent the resin material from invading, the partition portion 10 (inclined surface portion 8b and flat surface portion) of the slide type 8 is prevented. Since 8c) is in contact with the outer peripheral portion (inclined surface portion 5b and flat surface portion 5c) of the opening edge of the recess 5d provided in the upper mold 5, the mold does not need to be manufactured or positioned with high accuracy. However, the molds can be surely brought into close contact with each other, and the intrusion or leakage of the resin material can be surely prevented. As a result, the first cavity and the peripheral region thereof can be reliably partitioned, so that the shape accuracy and design of the resin molded product can be ensured, and the quality is improved. In addition, dimensional control and positioning control of the mold become easy.

In the example shown in FIG. 10, since the lower mold is provided with a convex portion for sealing the concave portion of the upper mold, the resin molded product obtained by this mold has a portion on the back side of the ridge portion. Traces (dents) of the convex part of the lower mold are formed in. On the other hand, in the present embodiment, since it is not necessary to provide such a convex portion, no trace (recess) of the convex portion is formed on the back side of the ridge portion. As shown in FIG. 2, in the panel 1 according to the present embodiment, the back surface of the first molded body 2 protrudes from the back surface of the second molded body 3, and is uniform without steps or irregularities in the length direction. It is molded into a flat surface (protruding surface).

Here, in the mold apparatus according to the present embodiment, the side surface of the recess 8a provided in the slide mold 8 is a straight surface extending in the slide direction, but as shown in FIG. 8, the side surface of the recess 8a. The lower portion may be an inclined surface 8d that is inclined downward so as to approach each other. With this configuration, when the slide mold 8 is lowered, the first molded body 2 easily peels off from the recess 8a, so that the first molded body 2 follows the slide mold 8 and falls off from the upper mold 5. It becomes possible to reduce the risk of doing so.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

In the description of each of the above-described embodiments, as a mold for molding the resin molded product, the first molding mold for molding the design surface side of the resin molded product is the upper mold, and the second molding mold for molding the back surface side of the resin molded product is formed. Although the case where the molding die is the lower die is taken as an example, the first molding die and the second molding die may be arranged upside down or left and right.

Further, the resin molded product molded by the mold apparatus or the molding method according to the present invention is not limited to the one made of resin materials having different colors. The present invention can also be applied to resin molded products molded from different types of resin materials such as texture and hardness in addition to color.

1 Instrument panel 2 1st molded body 2a ridge 3 2nd molded body 4 Mold device 5 Upper mold (1st molding mold)
5c recess 5c1 bottom 5c2 opening edge 6 lower mold (second molding mold)
7 Main type 8 Slide type 10 Partition 11 1st cavity 12 2nd cavity

Claims (2)

A first molded body in which a plurality of ridges and the ridges are connected to each other and a connecting portion having a width smaller than the width of the ridges is provided, and a second molded body in which the ridges are exposed from the design surface. A mold device for molding a resin molded product having a molded body.
A first cavity for molding the first molded body between the first molding die for molding the design surface side of the resin molded product and the back surface side of the resin molded product and the first molding die. And a second molding mold for defining the second cavity for molding the second molded body.
The first molding die has a recess for molding the ridge portion, a flat surface portion for molding the connecting portion, and a pair of inclined surface portions provided on both sides of the recess and the flat surface portion .
The second molding die includes the recess of the first molding die, the recess facing the flat surface portion, the pair of inclined surface portions of the first molding die facing the pair of inclined surface portions, and the first molding die. It has a pair of flat surface portions facing the flat surface portion of the second molding mold and provided between the recess and the pair of inclined surface portions.
The pair of inclined surface portions and the pair of flat surface portions of the second molding die come into contact with the pair of inclined surface portions and the flat surface portions of the first molding die, and the first molding die and the second molding die. A mold device characterized by functioning as a partition portion for partitioning and defining a first cavity communicating with each of the recesses in the peripheral region. A first molded body in which a plurality of ridges and the ridges are connected to each other and a connecting portion having a width smaller than the width of the ridges is provided, and a second molded body in which the ridges are exposed from the design surface. A molding method for molding a resin molded product having a molded body.
A recess forming a front Symbol ridges, and a flat surface portion for shaping the connecting portion, the concave portion and a pair of slant surfaces which are provided on both sides of the flat surface portion is provided, the design surface of the resin molded product The first molding mold that molds the side and
The concave portion of the first molding die, the concave portion facing the flat surface portion, the pair of inclined surface portions facing the pair of inclined surface portions of the first molding mold, and the flat surface portion of the first molding mold facing the flat surface portion. A pair of flat surface portions provided between the concave portion and the pair of inclined surface portions of the second molding die are provided, and the second molding die for molding the back surface side of the resin molded product is relatively close to each other. hand,
By contacting said pair of inclined surface portions and the pair of flat surface portions of the second mold with the pair of inclined surface portions and the flat surface portion of the first mold, the first mold and the second mold The step of partitioning the first cavity communicating with each of the recesses from the surrounding area and defining the cavity.
A step of filling the first cavity with a first resin material to form the first molded product, and
A step of defining the second cavity by relatively separating the first molding die and the second molding die while leaving the first molded body in the first cavity.
A method for molding a resin molded product, which comprises a step of filling the second cavity with a second resin material and molding the second molded product.

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