JP5418807B2 - Manufacturing method of composite molded product - Google Patents

Description

  The present invention relates to a method for manufacturing a composite molded article.

  Conventionally, manufacturing methods described in Patent Documents 1 to 6 below are known as methods for manufacturing a composite molded product obtained by integrally molding a first molded product and a second molded product. Among these, in Patent Documents 2 to 6, the first molded product is molded by the first mold, and after the first molded product is released from the first mold, the first molded product is held in the second mold. In this state, a method of manufacturing a composite molded product by injection molding a molten resin that becomes a second molded product is disclosed. In these manufacturing methods, it is necessary to manufacture the first mold and the second mold separately.

  On the other hand, as a technique in which a part of the first mold and a part of the second mold are shared, a manufacturing method described in Patent Document 1 is known. According to this manufacturing method, first, in the first molding step, the first molding die having a concave first molding surface and the second molding die having a convex second molding surface are closed, and both moldings are performed. Resin is injected into a first cavity formed between the surfaces to form a first molded product, and the first molded product is held on the first molded surface in a state where it is adhered to open both molds. Next, in the second molding step, the second molding die is replaced with a third molding die having a convex third molding surface, and both molding dies are closed. At this time, a second cavity is formed between the first molded product held on the first molding surface and the third molding surface, and a resin is injected into the second cavity to form the second cavity. A composite molded product is manufactured by integrally molding the first molded product and the second molded product by foaming the molded product.

According to this manufacturing method, since the second molded product is injected with respect to the first molded product, in particular, in the case of foam molding, the second molded product which is a foam molded product does not cause dents and the like. Molded articles can be manufactured. This is because when the first molded product is injected into the second molded product which is a foam molded product, the injection pressure or heat of the resin is applied to the second molded product which has been foam molded in advance. This is because destruction occurs and the surface of the second molded product is recessed, and such a problem can be avoided in advance. For this reason, it is desirable that the second molded product, which is a foam molded product, is foam molded after the first molded product is molded. The first molded product and the second molded product are held by holding the first molded product on the first molding surface. The mold is opened.
JP 2000-52377 A JP-A-7-195429 JP 2001-150483 A JP 2001-47465 A JP-A-9-332336 JP-A-6-6127

  However, in the above manufacturing method, since the second molding surface has a convex shape, when the first molding die and the second molding die are opened, the resin shrinks and the first molding product becomes the second molding product. The outer wall 2 provided on the outer periphery of the main body 1 is separated from the first molding surface 3 as shown in FIG. In this state, when the second mold 4 is replaced with the third mold 5 and the first mold 6 and the third mold 5 are closed, as shown in FIG. A part becomes a wrinkle 7, or a tear generate | occur | produces.

  The present invention has been completed based on the above-described circumstances, and prevents the first molded product from being separated from the first molding surface, thereby preventing the first molded product from being wrinkled or torn. The object is to produce molded articles.

  The present invention relates to a method of manufacturing a composite molded product obtained by integrally molding a first molded product and a second molded product, and between a first molded surface having a concave shape and a second molded surface having a convex shape. A first molding step for molding the first molded product, and a second molding step for foam-molding the second molded product between the first molded product and the third molded surface held on the first molding surface, The first molded product has a main body formed along the first molding surface and a form in which an outer wall provided on the outer periphery of the main body is folded back to the outer peripheral side, and the first molding surface is formed between the outer wall and the outer wall. It is characterized in that it is provided with a projection for sandwiching the opening edge of the.

  In this case, when the first molded product is molded in the first molding step and the first molded surface and the second molded surface are separated from each other, the opening edge portion of the first molded surface is the projection of the first molded product. It will be in the state clamped between outer wall parts, and a 1st molded product will be hold | maintained at a 1st molding surface. In the second molding step, a composite molded product is manufactured by foam-molding the second molded product between the first molded product held on the first molding surface and the third molding surface of the third mold. Therefore, by preventing the first molded product from being separated from the first molding surface, a composite molded product can be manufactured without causing wrinkles or tears in the first molded product. Further, the thickness of the composite molded product can be secured by foaming of the foaming agent. Therefore, the material amount of the second molded product can be reduced, and the weight of the composite molded product can be reduced.

  According to the present invention, it is possible to manufacture a composite molded product without causing wrinkles or tears in the first molded product by preventing the first molded product from separating from the first molding surface.

<Embodiment>
An embodiment of the present invention will be described with reference to the drawings of FIGS. FIG. 1 shows an example of a molding apparatus 10 for molding a vehicle interior material (an example of a “composite molded product” of the present invention) 50 according to the present embodiment. The mold 11 and the core 12 are movable in the horizontal direction. Is provided. A first mold 20 is provided at the center of the mold 11 in the vertical direction so as to protrude toward the core mold 12. The first molding die 20 is provided with a concave first molding surface 21. On the other hand, the core mold 12 is provided with a second mold 30 and a third mold 40 in order from the top, and the second mold 30 and the third mold 40 are provided so as to be movable in the vertical direction. It has been. The second molding die 30 is formed with a convex second molding surface 31, and the third molding die 40 is slightly smaller than the second molding surface 31 and has a convex third molding surface 41. Is formed.

  The vehicle interior material 50 of the present embodiment is formed by integrally molding a skin material (an example of the “first molded product” of the present invention) 60 and a base material (an example of the “second molded product” of the present invention) 70. It is a composite molded product. In addition, the skin material 60 is comprised by 1st resin which is thermoplastic resins, such as TPO resin (thermoplastic olefin resin), for example. Moreover, the base material 70 is foam-molded, for example with the 2nd resin which added the foaming agent to the polypropylene. As the foaming agent, for example, a chemical foaming agent or a physical foaming agent can be used. Examples of the chemical foaming agent include inorganic foaming agents such as sodium bicarbonate, ammonium bicarbonate and ammonium carbonate, nitroso compounds such as N, N′-dinitrosopentamethylenetetramine, azodicarbonamide, azobisisobutyronitrile and the like. Azo compounds, benzenesulfonyl hydrazide, toluenesulfonyl hydrazide, sulfonyl hydrazides such as diphenylsulfone-3,3′-disulfonyl hydrazide, p-toluenesulfonyl semicarbazide and the like can be used. As the physical foaming agent, for example, carbon dioxide gas or nitrogen gas can be used.

  As shown in FIG. 1, the first mold 20 includes two types of injection devices 22A and 22B. The first injection device 22A is a device that injects the first resin constituting the skin material 60, and is melted in the first cavity C1 formed between the first molding surface 21 and the second molding surface 31. The first resin is supplied to mold the skin material 60. The second injection device 22 </ b> B is a device that injects the second resin constituting the base material 70, and is between the skin material 60 and the third molding surface 41 held in a state of being adhered to the first molding surface 21. The base material 70 is molded by supplying the melted second resin into the formed second cavity C2.

  Next, a method for manufacturing the vehicle interior material 50 will be described. First, in the first molding step, as shown in FIG. 2, the first molding die 20 and the second molding die 30 are arranged side by side in the horizontal direction. When the molds 20 and 30 are moved in the horizontal direction and closed, a first cavity C1 is formed between the first molding surface 21 and the second molding surface 31, as shown in FIG.

  Here, the skin material 60 formed by the first cavity C1 is formed by folding the main body part 61 formed along the first molding surface 21 and the outer wall part 61A provided on the outer periphery of the main body part 61 to the outer peripheral side. It comprises a folded portion 62 that forms a shape and sandwiches the opening edge portion 23 of the first molding surface 21 with the outer wall portion 61A. Furthermore, the folded-back portion 62 includes a projecting portion 62A that projects from the outer edge of the outer wall portion 61A to the outer peripheral side, and a protrusion 62B that projects in the horizontal direction from the outer edge of the projecting portion 62A. That is, the first cavity C <b> 1 includes a first molding part C <b> 11 that molds the main body part 61 that becomes the skin material 60 and a second molding part C <b> 12 that molds the folded part 62.

  Further, since the inner side surface of the protrusion 62B is a vertically upright surface extending in the horizontal direction from the overhanging portion 62A, it is surely hooked to the opening edge portion 23 of the first molding surface 21. . Note that the inner surface of the protrusion 62B may be formed in an overhang shape toward the outer wall portion 61A, thereby further strengthening the catch on the opening edge portion 23 of the first molding surface 21. On the other hand, since the outer surface of the protrusion 62B is a gentle inclined surface toward the outer peripheral side, the protrusion 62B can be easily removed when the skin material 60 is removed from the first mold 20. .

  When the melted first resin constituting the skin material 60 is supplied to the first cavity C1, the first resin is filled in the first cavity C1 and cooled as shown in FIG. 60 is formed. At this time, the outer wall portion 61A tries to stick to the second molding surface 31 side by contraction of the first resin, but the opening edge portion 23 of the first molding surface 21 is between the protrusion 62B and the outer wall portion 61A. Therefore, the attachment of the outer wall portion 61A to the second molding surface 31 side is restricted. Therefore, as shown in FIG. 5, the outer wall portion 61 </ b> A is held in a state of being attached to the first molding surface 21 even when both the molds 20 and 30 are opened.

  Next, in the second molding step, as shown in FIG. 6, the first molding die 20 and the third molding die 40 are moved by moving both the second molding die 30 and the third molding die 40 upward. Arrange horizontally. When the molds 20 and 40 are moved in the horizontal direction and closed, the second cavity C2 is interposed between the skin material 60 held on the first molding surface 21 and the third molding surface 41 as shown in FIG. Is formed.

  When the melted second resin to which the foaming agent constituting the substrate 70 is added is supplied to the second cavity C2, as shown in FIG. 8, the second resin is filled into the second cavity C2. Then, the base material 70 is foam-molded by opening both the molds 20 and 40 by a predetermined distance and foaming the second resin. Then, when the skin material 60 is removed by air blow or the like while the molds 20 and 40 are opened, the skin material 60 and the base material 70 are integrally molded as shown in FIG. At this time, since the folded-back portion 62 protrudes to the outer peripheral side from the outer edge of the base material 70, end processing is performed by removing the protrusion 62B and folding the folded-back portion 62 back to the back surface of the base material 70. FIG. The vehicle interior material 50 shown in FIG.

  As described above, in the present embodiment, the outer wall portion 61A of the skin material 60 is folded back to the outer peripheral side to provide the folded portion 62. Therefore, when the skin material 60 is molded in the first molding process, the opening edge of the first molding surface 21 is formed. The portion 23 is sandwiched between the protrusion 62B and the outer wall portion 61A, and the outer wall portion 61A can be prevented from sticking to the second molding surface 31 side and being separated from the first molding surface 21. Therefore, when the base material 70 is molded in the second molding process, it is possible to prevent the skin material 60 from being wrinkled or torn. Therefore, the product quality of the vehicle interior material 50 can be improved. The vehicle interior material manufactured in this way can be applied to, for example, a door trim, an instrument panel, a seat back board, a partition board, a console box, a pillar garnish, a quarter trim, and the like.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) Although the present embodiment is applied to the vehicle interior material 50 as a composite molded product, according to the present invention, the present invention can be applied to molded products such as furniture, houseware, and daily necessities other than the vehicle interior material 50. Good.

  (2) Although this embodiment illustrates the molding apparatus 10 in which the mold 11 and the core mold 12 move in the horizontal direction, according to the present invention, the molding apparatus in which the mold 11 and the core mold 12 move in the vertical direction. It is good.

  (3) In the present embodiment, the protrusion 62B is connected to the outer wall part 61A via the protruding part 62A. However, according to the present invention, the protruding part 62A is not necessarily provided, and the protrusion 62B is directly connected to the outer wall part 61A. May be. In that case, the protrusion 62B may have a shape that is folded in an arc shape, for example.

  (4) In the present embodiment, the skin material 60 is held on the fixed first molding die 20 side. On the contrary, the first molding die 20 is movable and the second molding dies 30 and 40 are fixed. It is good also as the formed apparatus.

  (5) In the present embodiment, the second mold 30 and the third mold 40 are configured separately, but may be configured integrally.

Sectional drawing which showed an example of the shaping | molding apparatus in this embodiment Sectional drawing which showed the state before mold closing of the 1st mold and the 2nd mold Sectional drawing which showed the state in which the 1st cavity was formed by closing the 1st mold and the 2nd mold Sectional drawing which showed the state which supplied the 1st resin fuse | melted to the 1st cavity and shape | molded the skin material Sectional drawing which showed the state which opened the 1st shaping | molding die and the 2nd shaping | molding die, with the skin material affixed on the 1st shaping | molding surface Sectional drawing which showed the state before mold closing of the 1st mold and the 3rd mold Sectional drawing which showed the state by which the 1st shaping | molding die and the 3rd shaping | molding die were closed, and the 2nd cavity was formed Sectional drawing which showed the state which supplied the 2nd resin fuse | melted to the 2nd cavity, and shape | molded the base material Sectional drawing which showed the state which removed the 1st shaping | molding die and the 3rd shaping | molding die, and demolded the composite molded product formed by integrally forming a skin material and a base material Sectional drawing which showed the state which processed the edge part of the composite molded product formed by integrally molding a skin material and a base material, and the interior material for vehicles was completed Sectional drawing which showed the state in which the outer wall part was spaced apart from the 1st molding surface conventionally Sectional drawing which showed the state by which the 2nd molded product was foam-molded in the state which the wrinkles generate | occur | produced in the 1st molded product conventionally

Explanation of symbols

DESCRIPTION OF SYMBOLS 21 ... 1st molding surface 23 ... Opening edge part of 1st molding surface 31 ... 2nd molding surface 41 ... 3rd molding surface 50 ... Interior material for vehicles (composite molding product)
60 ... skin material (first molded product)
61 ... Body part 61A ... Outer wall part 62B ... Protrusion 70 ... Base material (second molded product)

Claims (1)

A method for producing a composite molded product obtained by integrally molding a first molded product and a second molded product,
A first molding step of molding the first molded product between a concave first molding surface and a convex second molding surface;
A second molding step of foam-molding the second molded product between the first molded product and the third molded surface held on the first molding surface,
The first molded product has a form in which a main body portion formed along the first molding surface and an outer wall portion provided on an outer periphery of the main body portion are folded back to the outer peripheral side, and between the outer wall portion and the outer wall portion. A projection for sandwiching the opening edge of the first molding surface ,
The first molding step includes a mold opening step of opening a first molding die having the first molding surface and a second molding die having the second molding surface,
The outer wall portion of the protrusion has a surface on the outer wall portion side that extends in the mold opening direction of the first mold and the second molding die in the mold opening process, or a surface that extends in the mold opening direction. A method for producing a composite molded product, characterized in that the surface is formed in an overhang shape toward the side .

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