JPH0872072A - Production of foamed molding - Google Patents

Abstract

PURPOSE: To certainly perform the fusing treatment of a trim by applying urethane rubber to the parting line parts of upper and lower molds to form a packing part and elastically deforming a part of the packing when the foamable resin raw material charged in a cavity is pressed to embed the same in the cavity in an annular state. CONSTITUTION: A urethane rubber coating layer 31b is formed to the parting line part 31 of a lower mold 11 among the parting line parts of upper and lower molds 11, 12 to form a packing part. A foamable resin raw material is charged in the cavity 2 formed by the upper and lower molds 11, 12 and, when the upper and lower molds 11, 12 are clamped, the coating layer 31b is pressed by the planar part 34a of the upper mold 12 and the right end of the urethane rubber coating layer 31b in the cavity 2 is expanded to form an annular embedded part 31c. When the raw material is subjected to foaming treatment in this state, an annular groove is formed to the peripheral edge part of a foamed molding 5 by the embedded part 31c and the fusing bead 54 of a trim enters the annular groove to certainly fuse upper and lower trims 51.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a foam-molded article for producing a foam-molded article by filling a cavity with a foamable synthetic resin and foaming.

[0002]

2. Description of the Related Art Since foamed products applied to pad materials such as sun visors are required to be lightweight and have shape retention, they are manufactured by using foamable synthetic resins such as urethane foam and polypropylene foam as raw materials. Many. Such a foamed product is manufactured by a low specific gravity (0.03 ~
0.05) of two flat plate slab pad materials are prepared, a slab pad material is sandwiched between two skins with a core material or the like being sandwiched between them, and the outer peripheral edge portion of these skins is welded. And a foaming raw material in which a foaming agent is mixed with a predetermined foamable synthetic resin prepared in a liquid or fine powder state is supplied into a cavity of a mold loaded with a core material, and then heated. There is a method in which a pad material is manufactured by a so-called integral foam molding method in which foaming treatment such as the above is performed, the surface of the pad material is sandwiched by two skins, and the peripheral edge portion is welded.

By the way, when a slab pad material is used for a foamed product, a so-called weld ball formed along the weld line penetrates into the soft slab pad material at the time of the welder treatment of the skin to increase the width of the weld line. Therefore, the upper and lower epidermis are bonded well. On the other hand, the specific gravity of the pad material manufactured by the integral foam molding method is usually about 0.11.
However, since the specific gravity is larger than that of the slab pad material, the pad material of the integral foam molding method is hard, and there is a circumstance that the welded ball cannot enter into the pad material during the welder process. Hereinafter, the production of a foamed product using a pad material by such an integral foam molding method will be described.

FIG. 6 shows a schematic sectional view of a conventional mold in which the integral foam molding method is used. As shown in this figure,
The mold 10 is composed of a lower mold 110 and an upper mold 120,
A lower mold cavity 210 and an upper mold cavity 220 are recessed in the surfaces of the two molds 110 and 120 that face each other. By combining these two cavities 210 and 220, a mold 10 that conforms to the outer shape of the molded product
Cavity 20 is formed.

The cavity 20 is filled with a molding material M in which a foamable synthetic resin and a foaming agent are mixed,
The lower mold 110 and the upper mold 120 are fastened together so as not to separate from each other, and then foaming treatment such as heating is performed to obtain a foam-molded article.

FIG. 7 is a partial cross-sectional perspective view showing a state in which the foam molded article manufactured as described above is covered with a trim. As shown in this figure, an upper trim 51a and a lower trim 51b are arranged on the upper surface and the lower surface of a pad material 50 which is a foam molded product.
The so-called ears 52 protruding to the side from the are welded by the pair of upper and lower welder blades W of the high-frequency welding device, and the ears 52 are cut off to trim-coated article 53.
Is obtained.

[0007]

By the way, in the conventional pad material 50 manufactured by the integral foam molding method as described above, when the ear portion 52 of the trim 51 is welded by the pair of upper and lower welder blades W. , Upper and lower ears 5
The abutting portions of 2 are mutually melted by heat to form so-called weld balls 54 and weld portions 55 as shown in FIG. 8A, but the specific gravity of the pad material is 0.11 and the slab pad is Since the specific gravity of the material is much larger than 0.03 to 0.05 and the material is so hard, a pad is formed on the back surface of the contact portion between the upper trim 51a and the lower trim 51b at the base end of the ear portion 52. The end of the material 50 comes into contact with the welded ball 54.
Is blocked by the end of the pad material 50 and cannot enter the inside of the trim 51, and is in a state of bulging between the upper and lower ears 52 outside the welder blade W.

Therefore, after the welding operation by the welder blade W, the welding balls 54 are welded by the welding balls 54 in a state in which the ears 52 are cut by pressing the blade tips of the upper and lower welder blades W, which are separated from each other, in the direction to bring them into contact with each other. The upper trim 51a and the lower trim 51b are securely welded to each other because they are formed only in a slight gap between the edge of the upper trim 51a and the edge of the lower trim 51b after the cutting process by W is completed. It had a problem that it could not be done.

Further, even if the welding is performed reliably, the welding area is small, so that the strength of the welding portion is weak and the welding portion is easily broken even when a slight external force is applied to the trim 51. Had.

Further, since the welded ball 54 formed inside the trim 51 is sandwiched between the end surface of the pad material 50 and the inner surface of the trim 51, the welded portion 55 depends on the condition of the welded ball 54. Asperities are formed in the horizontal direction in the longitudinal direction and meander in the vertical direction. As a result, there is a problem that a defective product having a bad appearance is likely to occur.

In order to solve the above-mentioned problems, an annular groove is formed in a portion of the pad material 50 facing the ear portion 52, and the welding ball 54 is guided into the annular groove. Those disclosed in Japanese Patent Application Laid-Open No. 62-101418. However, in the one disclosed in Japanese Patent Laid-Open No. 62-101418, in order to form the annular groove in the pad material 50, an annular groove is formed in the outer peripheral edge of the pad material 50 once obtained by foam molding. However, there is a problem in that the manufacturing cost is increased.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to reliably weld a trim covering a foam-molded article obtained by the integral foam-molding method. It is an object of the present invention to provide a method for producing a foam-molded article, which is less likely to break in a broken portion, has a reduced defect rate of the trim-coated article covered with trim, and can further reduce the production cost of the foam-molded article. .

[0013]

According to a first aspect of the present invention, there is provided a method for producing a foam-molded article, which comprises a foam-molding die including an upper mold and a lower mold which are recessed so that cavities face each other. In a method for producing a foam-molded article using the method, a mold in which a packing part is formed in advance by a flexible material is used for a parting line part of at least one of the upper mold and the lower mold. , A raw material loading step of loading a raw material of the expandable synthetic resin into the cavity of the mold,
After this raw material loading step, the upper die and the lower die are pressed together and the upper die and the lower die are fastened to each other while a part of the packing portion is elastically deformed so as to be annularly immersed in the cavity. The present invention is characterized in that a foam molded article is manufactured through a mold fastening step and a foaming step of foaming a raw material of a foamable synthetic resin in a cavity after the mold fastening step.

According to a second aspect of the present invention, there is provided a method for producing a foam-molded article by using a foam-molding die including an upper mold and a lower mold in which cavities are recessed so as to face each other. In a method for producing a foam-molded product to be produced, at least one of the upper die and the lower die has a parting line portion, and a mold having a packing portion having an annular recessed portion that is annularly recessed in the cavity is used in advance. A raw material loading step of loading a foamable synthetic resin raw material into the cavity of the mold, a die fastening step of fastening the upper die and the lower die to each other after the raw material loading step, and a die fastening step after the die fastening step. The present invention is characterized in that a foam molded article is manufactured through a foaming step of foaming a raw material of a foamable synthetic resin in a cavity.

According to a third aspect of the present invention, in the method for producing a foamed molded article according to the first or second aspect, the packing portion is formed by applying urethane rubber to a parting line portion. It is characterized by being formed by.

[0016]

According to the method for producing a foam-molded article according to the first aspect of the present invention, a metal having a packing part formed in advance on a parting line part of at least one of the upper mold and the lower mold by a flexible material is used. Since a mold is used, by pressing the upper mold and the lower mold together in the mold fastening process, the packing part is compressed, and a part of the packing part is annularly immersed in the cavity due to elastic deformation. . Therefore, when the foaming synthetic resin raw material loaded in the mold is subjected to the foaming process in the next foaming step, the peripheral portion of the foamed molded product obtained by a part of the packing part which is annularly immersed in the cavity is formed. The annular groove is formed in the groove.

According to the method for producing a foam-molded article according to the above-mentioned claim 2, a packing having an annular recessed portion which is previously annularly recessed in the cavity, is formed in at least one of the upper and lower mold parting line portions. Since a mold in which a part is formed is used, when the foaming synthetic resin raw material loaded in the mold is subjected to a foaming process in the foaming step, a part of the packing part which is annularly immersed in the cavity is formed. An annular groove is formed in the peripheral portion of the foam-molded product obtained by.

According to the foamed molded article manufacturing method of the third aspect, the packing portion can be easily formed only by applying urethane rubber to the parting line portion.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a partially cutaway perspective view showing an example of a mold applied to a method for producing a foam molded article according to the present invention. In this embodiment, the mold 1 is for manufacturing a sun visor for automobiles. As shown in this figure, the mold 1 is composed of a lower mold 11 having a lower mold cavity 21 provided on the upper surface thereof and an upper mold 12 having an upper mold cavity 22 provided on the lower surface thereof. . In the state where the lower mold 11 and the upper mold 12 are united with each other, the mold 1 is formed with the cavity 2 which is composed of the lower mold cavity 21 and the upper mold cavity 22 and which conforms to the outer shape of the foam-molded product. There is.

The mold 1 is press-fastened by a clamp 6 which is a press-fastening means as shown in FIG. 2, for example. The clamp 6 is not shown in FIG. The clamp 6 includes a base 61 provided on one side of the lower die 11, a bracket 62 provided upright on an upper part of the base 61, and a first support shaft provided on an upper center of the bracket 62. An operation arm 63 rotatably supported around 62a and a pressing arm for pressing the upper die 12 rotatably supported around a second support shaft 62b provided at the upper right end of the bracket 62. And 64. A pressing screw 65 is screwed onto the tip of the pressing arm 64 to stop and press the surface of the upper mold 12.

A locking rod 63a is provided on the operating arm 63 above the first support shaft 62a. And
With the pressing arm 64 rotated counterclockwise around the second support shaft 62b and pressing the surface of the upper die 12 by the pressing screw 65, the operation arm 63 is rotated counterclockwise around the first support shaft 62a. The locking rod 63a locks the clockwise rotation of the pressing arm 64 around the second support shaft 62b by maintaining the pressing state of the upper mold 12 surface by the pressing screw 65. ing.

On the other hand, a hinge 66 is provided on the other side of the die 1, and the lower die 11 and the upper die 12 are provided by the hinge 66.
And are combined. Then, the connecting shaft 66a of the hinge 66
The cavity 2 is opened by rotating the upper mold 12 counterclockwise, and the cavity 2 is closed by rotating the upper mold 12 clockwise around the coupling shaft 66a. .

While the cavity 2 is closed, the clamp 6 is operated, the pressing screw 65 of the pressing arm 64 presses the surface of the upper mold 12, and the operating arm 63 is operated to operate the pressing screw 65. By locking the pressed state, the lower mold 11 and the upper mold 12 are pressed and fastened.

A lower die parting line portion 31 and an upper die parting line portion 32 are provided at the abutting portions of the lower die 11 and the upper die 12, respectively, and both of these parting line portions 31, 32 are provided. The parting line portion 3 of the mold 1 is formed by.

In this embodiment, as shown in FIG. 3, the upper mold parting line portion 32 is formed by an annular protrusion 33 having a cutting edge portion 34 having a flat surface portion 34a having a minute width on the tip end surface thereof. Has been done. The width dimension d of the flat portion 34a is set to 0.5 mm to 2 mm. The width dimension d is most preferably about 1 mm.

A notch portion 34b is provided at an appropriate position of the cutting edge portion, and the air in the cavity 2 is led to the outside from the notch portion 34b during foam molding.
The flat surface portion 34 a is provided on the tip of the cutting edge portion 34 on the side of the cavity 2, and the lower mold 11 inside the cavity 2 is provided.
The contact portion between the upper mold 12 and the upper mold 12 is flush with the vertical direction.

On the other hand, the lower die parting line portion 31
Is formed on the surface edge of the lower mold cavity 21 so as to face the upper mold parting line portion 32. In this embodiment, the lower mold parting line portion 31 includes an adhesive layer 31a applied to the surface of the lower mold 11 and a urethane rubber coating layer (packing portion) laminated on the adhesive layer 31a.
And 31b.

The reason why the adhesive layer 31a is interposed below the urethane rubber coating layer 31b is to strengthen the bonding between the lower mold 11 made of metal and the urethane rubber coating layer 31b. This is because the urethane rubber coating layer 31b can be surely formed on the surface of the lower mold 11 by interposing the adhesive layer 31a having excellent affinity with both of the urethane rubber and the urethane rubber between them.

As the adhesive forming the adhesive layer 31a, a chloroprene rubber adhesive, a nitrile rubber adhesive, an epoxy resin adhesive, a polyurethane adhesive, or the like is preferably used. However, in this embodiment, a polyurethane adhesive is used.

As the urethane rubber (urethane type thermoplastic elastomer) forming the urethane rubber coating layer 31b, any of caprolactone type, adipic acid type and ether type is applied. In particular, the hardness of a sample is measured by dropping a hammer having a spherical diamond attached to its tip from a predetermined height so as to hit it perpendicularly to the sample surface, and measuring the hardness of the sample at the height at which the hammer bounces, the so-called Shore (A) hardness is 85 °. Those having elasticity in the front and rear are suitable.

In the present embodiment, as described above, the lower parting line portion 31 includes the adhesive layer 31a and the urethane rubber coating layer 31 laminated on the adhesive layer 31a.
Since it is formed by b, when the upper die parting line portion 32 and the upper die parting line portion 32 are superposed on each other, the clamp portion 6 presses the upper die parting line portion 32 and the flat portion 34a of the blade tip portion 34 with urethane rubber coating. Layer 3
1b is pressed.

In this state, the pressed portion of the flexible urethane rubber coating layer 31b is compressed, and the left and right portions of the pressed portion rise due to this compression, and in particular, the urethane rubber coating layer 31b shown in FIG. The left end portion is recessed into the cavity 2 and the annular recessed portion 31c is formed.

Therefore, when a foam molding process is performed using the mold 1 having such an annular recess 31c formed in the cavity 2, as shown in FIG. 5, a pad material (foam molded product) is obtained.
An annular groove 56 surrounding the pad material 5 is formed in the peripheral portion of the pad material 5.

The formation of the lower mold parting line portion 31 on the surface of the lower mold 11 will be described below with reference to FIG. FIG. 4 is a cross-sectional explanatory view illustrating a coating process of a parting line formed of a coating layer of urethane rubber,
(A) shows the state where the adhesive layer is formed on the parting line surface, (b) shows the state where the urethane rubber coating layer is formed on the adhesive layer, and (c) shows the surface where the urethane rubber coating layer is formed. It shows a state where it is processed so as to be flat.

First, the coated surface 11a, which is the upper edge of the lower mold cavity 21 and is formed annularly on the surface of the lower mold 11.
The masking material 4 is placed on the surface of the lower mold 11 so as to expose the lower mold 11 and is also fitted in the lower mold cavity 21. Then, in order to improve the adhesion performance, the exposed surface 11a to be coated is subjected to shot blasting. After that, the masking material 4 is removed, dust is removed by air blow, and the masking material 4 is mounted again.

Then, the masking material 4 is attached and an adhesive is applied to the exposed surface 11a exposed on the surface. As shown in FIG. 4A, the adhesive layer 3 having a thickness of about 0.2 mm.
1a is formed.

Next, urethane rubber is applied by brush coating from above the adhesive layer 31a so that the thickness per application is about 0.2 mm with the adhesive semi-dried. Then, in the semi-dried state of the applied urethane rubber, the urethane rubber is applied again to the application surface in the same manner as above. By repeating this coating operation a plurality of times, as shown in FIG.
As shown in (b) of (3), a urethane rubber application portion having a thickness of 0.5 mm to 3 mm is formed. The thickness of the urethane rubber coating layer is set to 3 mm or less,
It is preferably set to m.

After the urethane rubber coating operation is completed, the masking material 4 is removed, and then the surface of the urethane rubber coating portion is scraped off with a predetermined tool such as a cutter so that the surface of the urethane rubber coating portion is flattened. A urethane rubber coating layer 31b is formed as shown in (c). In the present embodiment, the surface of the urethane rubber coating portion shown in (b) and the portion protruding into the lower mold cavity 21 are scraped off, but the portion protruding into the lower mold cavity 21 is particularly scraped off. You don't have to.

The production of a foamed molded product using the mold 1 in which the urethane rubber coating layer 31b is provided on the lower mold parting line portion 31 as described above will be described below. First, in the raw material loading step, a molding raw material M in which a foaming synthetic resin raw material such as urethane foam or propylene foam is mixed with a predetermined foaming material is loaded into the lower mold 11 separated from the upper mold 12. .

Then, in the next die fastening step, as shown in FIG. 2, the lower die 11 and the upper die 12 are united and the clamp 6 fastens them together, and the flat surface of the blade tip portion 34 of the upper die 12 is joined. The urethane rubber coating layer 31b on the lower mold parting line portion 31 is pressed by the portion 34a. Then, as shown in FIG. 3, the urethane rubber coating layer 31
The pressed portion of b is compressed, the left and right of the pressed portion rise, and the right end portion of the urethane rubber coating layer 31b bulges inside the cavity 2
Is formed.

As described above, the annular recess 3 is formed in the cavity 2.
When a predetermined foaming process such as heating is performed in the next foaming step with 1c formed, the annular recess 31c is formed.
Thus, the annular groove 56 is formed in the peripheral portion of the pad material 5. After the foaming process is completed, the fastening of the mold 1 by the clamp 6 is released, and the pad material 5 is taken out from the cavity 2 of the mold 1.

The operation of covering the pad material 5 manufactured as described above with the trim 51 will be described below with reference to FIG. FIG. 5 is an explanatory view of a cross-sectional view for explaining a process of mounting the trim on the foam-molded product, (a) shows a state before the upper and lower trims are welded by the welder blade, (b)
Shows a state in which the upper and lower trims are being welded by the welder blade, and (c) shows a state in which the ears are cut after the upper and lower trims are welded by the welder blade.

First, as shown in FIG. 5A, the pad material 5 is mounted on a high frequency welding device (not shown) while being covered with a lower trim 51b and an upper trim 51a which are slightly larger than the pad material 5. As the material of the trim 51, polyvinyl chloride (polyvinyl chloride) which is a thermoplastic synthetic resin is generally used. In this embodiment, a woven cloth laminated with a vinyl chloride sheet is used. In addition, F in the drawing represents the frame of the sun visor embedded in the pad material 5. The upper and lower welder blades W of the high-frequency welding device are located slightly outside the edge of the pad material 5 and above and below the trim 51 extending outward from the edge of the pad material 5.

Next, the upper and lower welder blades W which were separated from each other
Are pressed toward each other, and high frequency is applied to the contact portion of the trim 51 from the welder blade W in a state where the upper trim 51a and the lower trim 51b are in contact with each other. As shown, the contact portion of the trim 51 becomes hot and melts to form the welded ball 54. This welded ball 54 is an annular groove 5 formed on the edge of the pad material 5.
6 and the welded ball 54 causes the upper trim 5
The end of 1a and the end of the lower trim 51b are firmly connected.

After the welding process for a predetermined time, a larger force is applied to the pair of upper and lower welder blades W,
As shown in (c) of the same figure, the ear portion 52 formed on the outer side of the welder blade W is cut and removed, and the trim covered product 53 is obtained.

As described in detail above, the method for producing a foam-molded product of the present invention uses the mold 1 in which the lower mold parting line portion 31 is formed of the urethane rubber coating layer 31b, and therefore the lower mold is applied. In a state where the upper mold 12 and the upper mold 12 are united, the flat surface portion 34a of the annular projection 33 forming the upper mold parting line portion 32 comes into contact with the urethane rubber coating layer 31b and bites into the coating layer, and as a result, the lower mold is formed. No gap is formed on the contact surface between the parting line portion 31 and the upper mold parting line portion 32, and the annular recessed portion 31c is formed in the cavity 2 due to the swelling of the urethane rubber coating layer 31b. It is easily formed without performing such cutting.

Therefore, an annular groove 56 is formed in the peripheral edge portion of the pad material 5 foam-molded in the cavity 2 by the annular recessed portion 31c, and the existence of the annular groove 56 makes it possible to mount the trim 51 later. , The welding ball 54 formed in the portion held by the welder blade W of the trim 51 enters the annular groove 56, and the variation in the production amount of the welding ball 54 is effectively absorbed. The unevenness of the trim surface caused by the variation is eliminated, and the upper trim 51a and the lower trim 51b are formed by the welded balls 54 entering the annular groove 56.
And are securely joined together.

In the above embodiment, the annular recessed portion 31c is formed by pressing the urethane rubber coating layer 31b by the cutting edge portion 34 of the upper die 12, but the present invention is annular. The recessed portion 31c is not limited to be formed by being pressed by the blade tip portion 34 of the upper die 12 of the urethane rubber coating layer 31b, and may be previously projected from the lower die parting line portion 31 into the cavity 2. It may be formed as follows.

To this end, in the step of removing the urethane rubber shown in FIG. 4C, the portion protruding into the lower mold cavity 21 of the urethane rubber coating layer 31b may be left without being removed. . By doing so, the annular recessed portion is conveniently formed even if the urethane rubber coating layer 31b is not strongly pressed by the blade tip portion 34 of the upper mold 12.

Further, in the present embodiment, the urethane rubber coating layer 31b as the packing part is formed by coating the parting line of the lower mold 11 with urethane rubber, but in the present invention, urethane rubber is coated. However, the present invention is not limited to this, and only the packing portion may be previously made of a flexible material, and the packing portion may be attached to the parting line.

In this embodiment, the mold 1 for manufacturing the sun visor for automobiles is exemplified, but the mold applied to the present invention is not limited to the one for the sun visor. It may be a mold for seats or other molds for foam molding.

[0052]

According to the method for producing a foam-molded article according to the first aspect of the present invention, a packing part is made of a flexible material in advance in the parting line part of at least one of the upper mold and the lower mold. Since the formed mold is used,
In the mold fastening process, the upper mold and the lower mold are pressed against each other in a state where the upper mold and the lower mold are combined with each other, whereby the packing part is compressed, and a part of the packing part is annularly retracted into the cavity by elastic deformation. Therefore, when the foaming synthetic resin raw material loaded in the mold is subjected to the foaming process in the next foaming step, the peripheral portion of the foamed molded product obtained by a part of the packing part which is annularly immersed in the cavity is formed. The annular groove is formed in the groove.

The foamed molded product having the annular groove formed in the peripheral edge portion is clamped by a pair of trims, and if the abutting portions of the trims are welded with the contacting portions corresponding to the annular groove, the trim is obtained. Since the welded ball formed by the melting of is put into the above-mentioned annular groove, the welded area of the pair of trims becomes large due to the presence of this welded ball, and a trim-covered product in a surely and firmly joined state can be obtained. .

Further, even if there is a variation in the production amount of the welded beads over the peripheral portion of the foam-molded article, this variation is absorbed by the welded balls entering the annular groove, and as a result, the outer surface of the trim coated article is absorbed. The unevenness and the meandering of the welding line caused by the variation in the amount of welded balls produced are effectively suppressed,
It is possible to reliably reduce the incidence of defective products.

According to the method for producing a foam-molded article according to the second aspect of the present invention, an annular recessed portion that is previously annularly recessed in the cavity is provided in the parting line portion of at least one of the upper mold and the lower mold. Since the mold in which the packing part has is used is used, when the foaming synthetic resin raw material loaded in the mold is subjected to the foaming process in the foaming step, the packing part which is annularly immersed in the cavity is An annular groove is formed in the peripheral portion of the foam-molded product obtained by a part.

A foam molded article having an annular groove formed at the peripheral edge thereof is held by a pair of trims, and if a contacting portion of these trims is subjected to a welding treatment in a state corresponding to the annular groove, the trim is obtained. Since the welded ball formed by melting of the above will enter the annular groove, the welded area of the pair of trims becomes large due to the presence of this welded ball, and they are the reliable and firmly joined trim-coated products. can get.

Further, even if there is a variation in the amount of the welded balls produced over the peripheral edge of the foam molded article, this variation is absorbed by the welded balls entering the annular groove, and as a result, the outer surface of the trim coated article is absorbed. The unevenness and the meandering of the welding line caused by the variation in the amount of welded balls produced are effectively suppressed,
It is possible to reliably reduce the incidence of defective products.

According to the method for producing a foam-molded article according to the third aspect of the present invention, the packing part can be easily formed by simply applying urethane rubber to the parting line part.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing an example of a mold applied to a method for producing a foam-molded article according to the present invention.

FIG. 2 is an explanatory view in cross-section showing an example of a pressing and fastening means of a mold.

FIG. 3 is a cross-sectional view illustrating a joined state of the parting line portions of the upper die and the lower die, illustrating a state in which an annular ridge is formed in the cavity by mutual pressing of the two dies.

FIG. 4 is a cross-sectional explanatory diagram illustrating a coating process of a parting line portion formed of a coating layer of urethane rubber,
(A) shows the state where the adhesive layer is formed on the parting line surface, (b) shows the state where the urethane rubber coating layer is formed on the adhesive layer, and (c) shows the surface where the urethane rubber coating layer is formed. The respective states are shown so that they are processed to be flat.

FIG. 5 is an explanatory view of a cross-sectional view for explaining a step of attaching a trim to a foam-molded article, where (a) is a state before the upper and lower trims are welded by a welder blade, and (b) is a top and bottom. The trim is being welded by the welder blade, and (c) shows the state in which the ears are cut after the upper and lower trims are welded by the welder blade.

FIG. 6 is an explanatory view of a cross-sectional view showing a conventional mold for foam molding.

FIG. 7 is a partial cross-sectional perspective view showing a state where the foam molded article is covered with a trim.

FIG. 8 is a cross-sectional view of a trim-covered product, in which (a) shows a state in which a pair of upper and lower trims are being welded by a welder blade, and (b) shows a state in which the ears of the trim are cut.

[Explanation of symbols]

 1 Mold 11 Lower Die 12 Upper Die 2 Cavity 21 Lower Die Cavity 22 Upper Die Cavity 3 Parting Line Part 31 Lower Die Parting Line Part 31b Urethane Rubber Coating Layer (Packing Part) 32 Upper Die Parting Line Part 31a Adhesive layer 31c Annular recessed part 33 Annular projection 34 Blade edge part 34a Flat surface part 34b Notch part 4 Masking material M Molding material 5 Pad material (foam molding)

Claims (3)

[Claims] 1. A method for producing a foam-molded article, comprising the steps of producing a foam-molded article using a foam-molding die comprising an upper die and a lower die having cavities facing each other. A raw material loading step of loading a raw material of a foamable synthetic resin into a cavity of a mold using a mold in which at least one parting line of the mold has a packing formed of a flexible material in advance. After the raw material loading step, the upper die and the lower die are pressed against each other, and the upper die and the lower die are fastened to each other in a state where a part of the packing part is elastically deformed so as to be annularly immersed in the cavity. A method for producing a foam-molded article, comprising: performing a mold-fastening step, and performing a foaming step of foaming a raw material of a foamable synthetic resin in a cavity after the mold-fastening step. 2. A method for producing a foam-molded article, which comprises producing a foam-molded article using a mold for foam-molding comprising an upper die and a lower die in which cavities are provided so as to face each other. At least one parting line part of the mold is a mold having a packing part having an annular recess that is annularly recessed in the cavity in advance, and the raw material of the foamable synthetic resin is inside the cavity of the mold. A raw material loading step of loading the raw material, a mold fastening step of fastening the upper mold and the lower mold to each other after the raw material loading step, and a foaming step of foaming the raw material of the foamable synthetic resin in the cavity after the mold fastening step. A method for producing a foam-molded article, comprising the step of producing a foam-molded article. 3. The method for producing a foam-molded article according to claim 1, wherein the packing part is formed by applying urethane rubber to the parting line part.