JPH0431499B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a method of manufacturing an integrally foamed molded article, and particularly to a method of manufacturing an integrally foamed molded article suitable for application to the manufacture of headrests for automobiles.

(Prior Art) One type of integral foam molded product is one whose outer surface is composed of a skin or a leather-like surface layer formed on the outer surface of a foamed body. Typical examples include automobile headrests, safety pads, and armrests.

By the way, in recent years, integrated foam molded products whose outer surface is composed of a skin or a leather-like surface layer (hereinafter simply referred to as the skin), particularly automobile headrests, have been developed with the aim of improving their aesthetic appearance and sense of luxury. As a result, the outer surface is now constructed of skins of different colors and materials.In such cases, conventionally, the skins of different materials were sewn or welded together in advance into a bag shape. However, the skin that has been sewn or welded into a bag shape is filled with a foaming material and foamed, and the step of sewing or welding the skin into a bag shape is essential. Therefore, conventionally, the manufacturing thereof has been troublesome. In addition, in the past, such skins were sewn or welded with the joined parts of each skin on the front side, so it was necessary to turn the joined bag-shaped skins inside out.
It is necessary to leave a part of the foam in an unbonded state, and therefore, the appearance of the molded product is inevitably damaged by the foam leaking from the unbonded part, and after the foaming operation of the foaming raw material is completed, the foam leaks from the unbonded part. There was a problem that required repair of the joint.
This problem of repairing unjoined parts is also a problem in cases where the outer skin is formed into a bag shape by rotational molding or blow molding, but where a predetermined core is inserted and buried inside, such as in the headrest of an automobile. It was similarly inherent in things.

Therefore, the inventor of the present application first filed a patent application filed in 1983-
In the specification of No. 256238, a pair of molds each giving a divided body in the shape of dividing an integrally foamed molded product into two are used to vacuum-form the skins corresponding to the divided bodies, and then a predetermined foaming raw material is applied. By filling and integral foam molding, a pair of foam semi-finished products (semi-finished products) each having a skin on the surface corresponding to the outer surface of the integral foam molded product and a predetermined recess on the surface corresponding to the dividing surface are formed. body semi-finished products)
After that, molds are matched so that the dividing surfaces of the pair of foam semi-finished products match.
By filling the space (recess) formed between the pair of foam semi-finished products with foaming raw material and performing secondary foam molding, an integrally foamed product whose outer surface is composed of a skin is created. A method for manufacturing molded products was proposed.

According to this method, the troublesome process of sewing or welding the skin into a bag shape can be omitted, and the problems of conventional methods, such as leakage of foam to the outside and spoiling the appearance of the molded product, can be eliminated. It can be avoided. In addition, even in products where the core is inserted or buried inside, such as the headrest of an automobile, by inserting the core from between the split surfaces of the foam semi-finished product, the core can be easily inserted without causing foam leakage. Therefore, it is possible to avoid the problem of repairing the unjoined portions caused by inserting the core.

(Problem) However, in the manufacturing method of integrally foamed molded products proposed in the above specification, the skin corresponding to each segment was manufactured by vacuum forming, so the skin There was a problem that the materials that could be used were limited to materials that could be vacuum formed, and especially when using cloth as the outer skin, there was a problem that it was impossible to use materials with poor extensibility. . Furthermore, no consideration was given to constructing one or both of the semi-finished foam products from integral foam having a leather-like surface layer, and in this sense as well, the materials that could be used for the skin were limited.

(Solution Means) Here, the present invention has been made against the background of the above-mentioned circumstances, and its feature is to manufacture an integrally foamed molded product having a skin or leather-like surface layer. (a) Separately manufactured skins corresponding to the divided bodies are set on the first mold which gives the divided bodies each having the shape of vertically dividing the molded product into two, and then the predetermined The outer surface of the integrally foamed molded product is filled with a foaming raw material and subjected to primary foaming molding, or by directly filling one or both of these molds with a prescribed foaming raw material and performing primary foaming molding. A pair of foam semi-finished products, each of which has a corresponding surface formed by the skin or a leather-like surface layer formed by a foaming operation of the foaming raw material, and a predetermined recess is formed in the surface corresponding to the dividing surface. (b) the pair of foam semi-finished products obtained in the semi-finished product manufacturing process are placed in a second mold for producing the integrally foamed molded product; After setting them so that they match, a predetermined foaming raw material is filled into the space formed by the recesses of the semi-finished foam products butted against each other during the setting operation, and secondary foaming is performed. The method includes a step of joining the semi-finished product by filling the space with the foam to be generated and simultaneously joining the pair of foamed semi-finished products to form the integrally foamed molded product. There is a particular thing.

(Operations/Effects) According to the method according to the present invention, the trouble of sewing or welding the skin into a bag shape is avoided, similar to the method of manufacturing an integrally foamed molded product proposed in the above specification (Japanese Patent Application No. 59-256238). This makes it possible to omit many steps, and it is also possible to avoid the problems of conventional methods, such as leakage of foam to the outside and spoiling the appearance of the molded product.
In addition, even in products where the core is inserted and buried inside, such as the headrest of an automobile, the core can be easily buried without causing foam leakage, and the unbonded parts caused by inserting the core can be easily buried. Repair problems can also be avoided.

Moreover, according to the method of the present invention, the skin of each foam semi-finished product can be manufactured by a method other than vacuum forming, such as blow molding, slush molding, injection molding, convex vacuum molding, sewing, etc. Therefore, it has become possible to use a skin made of a material that could not be used with the method proposed in the above specification, especially a cloth material with poor extensibility. In addition, according to the method of the present invention, since a separately manufactured skin is used when producing a foam semi-finished product, each skin can be produced separately from the production of each foam semi-finished product and even the integral foam molded product. There are advantages.

Furthermore, according to the method of the present invention, one or both of the semi-finished foam products can be composed of integral fluor having a leather-like surface layer, so that it can be used as a skin (including the leather-like surface layer). This expanded the selectivity of materials, and this also increased the degree of freedom in designing integrally foamed molded products.

In addition, in the method of the present invention, the manufacturing process of each foam semi-finished product in the semi-finished product manufacturing process and the semi-finished product joining process of joining these foam semi-finished products to form an integral foam molded product can be managed separately. In this sense as well, there is an advantage that manufacturing control of the integrally foamed molded product is easy. In addition, with the method of the present invention, it is possible to select different foam raw materials when manufacturing each foam semi-finished product (primary foam molding), and the foam raw materials are It is possible to give different feelings to the semi-finished body products. Furthermore, the shape and wall thickness of the foam layer of each foam semi-finished product, the foam raw material used for secondary foam molding, etc. can be selected as appropriate depending on the purpose.
It is possible to adjust the feel as appropriate by combining them.

(Examples) Hereinafter, in order to clarify the present invention more specifically, examples thereof will be described in detail based on the drawings. In the following description, an example will be described in which the present invention is applied to the production of a perforated head rest for an automobile, but the present invention is not limited to this, and can be applied to a type of head rest or safety pad that does not have a perforated part. It can also be applied to the production of other integrally foamed molded products such as , armrests, etc.

First, FIG. 1 shows a perspective view of a headrest manufactured according to the method of this embodiment, and FIG. 2 shows a partially cutaway view thereof. In those figures, 12 is the headrest main body, and a pair of stays 14, 1
4 allows it to be attached to a car seat (not shown).

The headrest main body 12 is an integrally foamed molded product having a substantially rectangular frame shape with a cavity 16 in the center, and the molded product is vertically divided into two parts at a dividing surface 18 to form a pair of semi-finished foam products 20. , 22 are integrally joined at the dividing surface 18. Each foam semi-finished product 20, 22 has a skin 24, 26 on the surface corresponding to the outer surface of the molded article, and edges 28, 30 of the skin 24, 26.
are each bent inward by a predetermined length along the dividing plane 18 to form an opening 3 of the same size.
2 and 34 are formed correspondingly. Furthermore, inside the epidermis 24 and 26, the epidermis 2 is
Recess 3 having openings 32 and 34 of 4 and 26 as openings
A foam layer 40, 42 of a predetermined thickness is provided with a thickness of 6, 38. Then, such foam semi-finished products 20 and 22 are butted together with their dividing surfaces 18 aligned, and the recesses 36 and 38 are formed.
The headrest main body 12 is constructed by filling the space formed by the butt-butting with foam 44 and joining them together.

Note that the stay 1 is provided inside the foam 44.
A core body 46 integrally formed with 4 and 14 is buried therein. Further, here, a fabric material laminated with a thermoplastic resin sheet on the inside is used as the skin 24, and a thermoplastic resin sheet is used as it is as the skin 26.

Next, a detailed procedure for manufacturing the headrest as described above will be explained with reference to FIGS. 3 to 8. As is clear from these figures, here,
FIGS. 3 to 5 show the manufacturing procedure of the foam semi-finished product (here, the foam semi-finished product 20), and FIGS. 6 to 8 show the process of joining the foam semi-finished products 20 and 22 together. The steps to perform the headrest are shown respectively. Therefore, in the following, we will first refer to Figures 3 to 3.
The procedure for manufacturing each foam semi-finished product 20, 22 will be explained according to FIG. 5, and then the steps shown in FIGS.
The steps for joining the foam semi-finished products 20 and 22 to form a headrest will be explained according to the diagram, but these steps do not necessarily have to be carried out as a series of steps, and are usually carried out independently from each other. The Rukoto. In addition, each foam semi-finished product 2
0 and 22 have the same manufacturing process except for the materials used such as the mold and skin, so only the case of manufacturing one foam semi-finished product 20 will be explained in detail, and the manufacturing process of the other foam Body semi-finished product 22
A detailed explanation of the manufacturing procedure will be omitted.

That is, when manufacturing the foam semi-finished product 20, first, as shown in FIG. A separately produced skin 24 corresponding to the molding surface and the mold mating surface is set on the middle mold 50, so as to cover the molding surface and the mold mating surface. Note that the medium size 50 is for defining the edge 28 of the skin 24, and is made of a plate material of a predetermined thickness.
The structure has a cavity 52 corresponding to the opening 32 of the skin 24. Further, the epidermis 24 is
For example, it is manufactured by blow molding, slush molding, injection molding, convex vacuum molding, sewing, etc., and as is clear from the figure, at this stage, the outer surface of the foam semi-finished product 20 is The shape is somewhat different from that of the outer skin 24.

Next, the inside of the skin 24 set in this way is filled with a predetermined primary foaming material 54 through the opening 32, and then, as shown in FIG.
For the primary molding lower mold 48 (middle mold 50), the skin 2
A primary forming upper mold 58 having a protrusion 56 projecting inwardly from the middle mold 50 is fitted to close the cavity 52 of the middle mold 50, that is, the opening 32 of the outer skin 24. In this state, the primary foaming raw material 54 is foamed (primary foaming molding) to form the foam layer 40 of the predetermined thickness inside the skin 24. After forming the foam layer 40, as shown in FIG. 5, the excess portion of the skin 24 is cut and removed along the openings 32, thereby obtaining the foam semi-finished product 20 as described above. That will happen. As is clear from FIG. 6, the protrusion 56 of the primary molding upper mold 58 is annularly protruded, and the recess 36 is aligned with the protrusion 5.
6. Also,
As described above, the other foam semi-finished product 22 is also manufactured separately according to the same procedure using the corresponding primary molding lower mold, middle mold, and primary molding upper mold. However, the primary foaming raw material used in producing the foam semi-finished product 22 does not necessarily have to be the same as the primary foaming raw material 54 used in producing the foam semi-finished product 20.

On the other hand, in order to integrally join the foam semi-finished products 20 and 22 manufactured according to such a procedure to form a headrest, as shown in FIG. A mold similar to or common to one of the lower molding molds is used as the secondary molding lower mold 6.
0, and a mold similar to or common to the other mold is used as the secondary molding upper mold 62. Note that here, a mold similar to the primary molding lower mold 48 used for manufacturing the foam semi-finished product 20 is used as the secondary molding lower mold 6.
0, and a mold similar to the primary molding lower mold used for manufacturing the foam semi-finished product 22 is used as the secondary molding upper mold 62.

That is, in order to join the foam semi-finished products 20 and 22, as shown in FIG. While the body semi-finished products 20 and 22 are set, the core body 46 integrally formed with the stays 14 and 14 is set. As shown in FIG. 7, the recess 36 of the foam semi-finished product 20 set in the lower secondary mold 60
A predetermined secondary foaming raw material 64 is filled in the foam, and as shown in FIG. The molds 18 are matched, and the secondary foaming raw material 64 is foamed (secondary foaming molding). As a result, the recess 36 of each foam semi-finished product 20, 22,
The foam 44 is placed in the annular space formed by the foam 44.
The foam 44 filled in this space joins the foam semi-finished products 20 and 22 together to form the headrest main body 12 and, ultimately, the headrest. . The secondary foaming raw material 64 may be the same as one or both of the primary foaming raw materials, or may be different from them. Further, the core body 46 is a secondary foaming raw material 64
can be set after filling.

The headrest manufactured by the above-described procedure includes the headrest main body 1 as described above.
Since the outer surface of 2 is composed of the skins 24 and 26 that are manufactured as separate members, as mentioned above, by employing different materials for the skins 24 and 26 (here, cloth is used as the skin 24). The outer surface of the skin 26 is made of a thermoplastic sheet), and its appearance can be easily varied, compared to a skin whose outer surface is made of the same material, such as a thermoplastic sheet. This can improve the aesthetic appearance and sense of luxury. Moreover, according to the method according to this embodiment, although the outer surface is composed of the skins 24 and 26 made of different materials, unlike the conventional method, the skin is sewn into a bag shape. There is no need for troublesome processes such as welding or welding, and therefore a head rest with such an outer surface can be manufactured easily and at low cost. Furthermore, if the method of this example is followed, the problems of the conventional method, such as the leakage of foam from the unjoined portion of the bag-shaped skin and the deterioration of the appearance of the molded product, can be avoided, and a head rest with an excellent appearance can be obtained. Therefore, the insertion and embedding operations of the core body 46 can be easily performed without causing such problems.

Further, according to the method of this embodiment, the epidermis 24, 26
Methods other than vacuum forming, such as blow molding,
It is possible to use products manufactured by methods such as slush molding, injection molding, convex vacuum molding, and sewing, which is superior to the manufacturing method proposed by the inventor in the above specification (Japanese Patent Application No. 59-256238). hand,
Selectivity of materials that can be employed as the skins 24, 26;
As a result, the selectivity of the appearance, feel, etc. of the headrest 10 is greatly expanded, which is extremely advantageous in terms of headrest design.

Furthermore, according to the method of this embodiment, each epidermis 24,
26 manufacturing processes, the manufacturing process of each of the foam semi-finished products 20 and 22, and the joining process of joining these foam semi-finished products 20 and 22 together to form the headrest can be managed independently. It becomes easier.

Note that in this embodiment, the edges 2 of the skins 24 and 26
8 and 30 are the dividing surfaces 1 of each foam semi-finished product 20 and 22
Although it is made to extend a predetermined length on the 8 side, the epidermis 2
The edges of the foam layers 4 and 26 do not necessarily have to extend toward the dividing surface 18, and it is also possible to configure the foam layers 40 and 42 to be in direct contact with each other. However, for aesthetic reasons or to maintain the peel strength of the skins 24, 26 above a certain level, as in this embodiment, the edges 26, 28 of each skin 24, 26 are extended a predetermined length toward the dividing surface 18. It is desirable to let them come out.

Furthermore, in this embodiment, the skins 24 and 26 are made of different materials, but
The constituent materials of the skins 24 and 26 may be the same. Even in such cases,
It is possible to enjoy the effects of simplifying the manufacturing process of the headrest.

Furthermore, in this embodiment, the foam semi-finished products 20, 2
Both the skins 24 and 26 of the foam layers 40 and 42 were made of a material different from that of the foam layers 40 and 42, but one or both of the foam semifinished products 20 and 22 were made of integral foam, and their outer surfaces The foam layer 4
It is also possible to configure it with a leather-like surface layer formed at the same time as the formation of 0,42. By constructing one or both of the foam semi-finished products 20, 22 from such an integral foam, it is possible to further simplify the manufacturing process of the foam semi-finished products 20, 22 and, by extension, the headrest.

Although the embodiments of the present invention have been described in detail above, these are merely examples, and the present invention is not limited to these specific examples, and various changes, modifications, and improvements can be made without departing from the spirit thereof. It goes without saying that the present invention can be implemented in a manner in which the following steps are taken.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a headrest manufactured by the manufacturing method according to the present invention, and FIG. 2 is a partially cutaway view thereof. Figure 3, Figure 4, Figure 5
Figures 6, 7 and 8 are respectively
It is an explanatory view for explaining the manufacturing process of the headrest shown in the figure. 12: Headrest body, 14: Stay, 1
8: Parting surface, 20, 22: Foam semi-finished product, 24,
26: Skin, 28, 30: Edge, 36, 38: Recess, 40, 42: Foam layer, 44: Foam, 46:
Core body, 48: Primary molding lower mold, 50: Medium mold, 54:
Primary foaming raw material, 56: protrusion, 58: primary molding upper mold, 60: secondary molding lower mold, 62: secondary molding upper mold,
64: Secondary foaming raw material.

Claims (1)

[Scope of Claims] 1. A method for producing an integrally foamed molded product having a skin or a leather-like surface layer, comprising: a first molding step for producing divided bodies each having a shape in which the molded product is vertically divided into two; After separately fabricating skins corresponding to the divided bodies are set on the mold, a prescribed foaming raw material is filled and primary foam molding is performed, or one or both of the molds is filled with a prescribed foaming material. By directly filling the foaming raw material and performing primary foam molding, the surface corresponding to the outer surface of the integrally foamed molded product is composed of the skin or a leather-like surface layer formed by the foaming operation of the foaming raw material. Also, a semi-finished product manufacturing step of manufacturing a pair of foam semi-finished products each having a predetermined recess formed in a surface corresponding to the dividing surface, and a step of manufacturing the pair of foam semi-finished products obtained in the semi-finished product manufacturing step. After setting the integrally foamed molded products in a second mold such that their dividing surfaces match, the recesses of the semifinished foam products are brought into contact with each other in the setting operation. By filling the space thus formed with a predetermined foaming raw material and performing secondary foam molding, the space is filled with the foam to be generated, and at the same time, the pair of foamed semi-finished products are integrally joined. A method for producing an integrally foamed molded product, comprising: a step of joining the semi-finished product with the integrally foamed molded product.