JPH08183042A - Core material for foam molding and production of foamed molded product - Google Patents

Abstract

PURPOSE: To prevent that cost such as material cost is increased by providing a runner to the outside of the cavity of a mold and to economically produce a foamed molded product of good quality free from underfill. CONSTITUTION: A raw material guide part 12 is formed in the vicinity of the injection port 11 of the surface on the side of the foam of a core material 10 along the longitudinal direction of the core material and the core material is attached to the molding surface of one split mold 21 having an injection nozzle inserting port 24 formed thereto and a liquid foamable raw material is injected in the cavity on one side of the core material through the injection nozzle inserting port and the injection port and the formed foam is integrated with the core material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foam molding core material and a method for producing a foam molding product.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 14 and FIG. 15 showing a cross section of an instrument panel of an automobile, one of core materials 71 made of a hard synthetic resin or the like is molded into a predetermined shape. In many cases, a foam molded product 70 is integrally provided on the side with a foam 72 such as polyurethane resin together with a surface skin 73.

The foamed molded product 70 is manufactured as follows using a split mold (not shown) having a cavity having a desired molded product shape and having an injection nozzle insertion port formed therein. . That is, the core material 71 is arranged on one mold surface on which the injection nozzle insertion port is formed, the skin 73 is arranged on the other mold surface, and the molding die is closed. Through the formed injection port 74, the core material 7
Inject the liquid foaming raw material into the cavity between 1 and the skin 73,
The foam-molded article is manufactured by foam-curing. The foam-molded article may be molded without a skin depending on the application and then covered with a skin if necessary,
Alternatively, it may be molded without a core material and directly attached to a mating article.

By the way, the liquid foaming raw material increases in viscosity and fluidity as the reaction progresses. Therefore, in the production of a large-sized or horizontally long foam-molded article used for the instrument panel, the liquid foaming raw material is reduced in fluidity due to the increase in viscosity before reaching the cavity end far from the injection position. As a result, partial overfilling or underfilling occurs in the cavity, and defects such as lack of thickness are likely to occur in the foam. Therefore, in the past, in order to fill the liquid foaming raw material evenly into the mold, a runner along the longitudinal direction of the cavity is provided on the mold parting surface between the injection nozzle insertion port and the cavity, and the liquid is passed through the runner. Foaming raw material is injected into the cavity.

However, in this method, the runner portion is also filled with the liquid foaming raw material and hardens together with the liquid foaming raw material in the cavity, so that the obtained foam molded article corresponds to the runner portion. Have parts. as a result,
After that, the portion corresponding to the runner portion must be cut off, which causes a problem of increasing labor and processing cost. Further, since the liquid foaming raw material filled in the runner portion is wasted, there is a problem that the material cost increases.

[0006]

SUMMARY OF THE INVENTION The present invention has been proposed in order to solve such a problem, and prevents an increase in material cost and the like due to the provision of a runner outside the foam molded article. An object of the present invention is to provide a foam molding core material and a method for manufacturing a foam molding product, which can economically manufacture a foam molding product of good quality with no flesh.

[0007]

The invention proposed here is a first invention relating to a foam molding core material, a second invention relating to a method for producing a foam molding product including a core material, and a core material-free method. The third invention relates to a method for producing a foam-molded article. First, the first invention is a core material for foam molding, which has an injection port at a predetermined portion and injects a liquid foaming raw material from the injection port to form a foam on one side. The present invention relates to a foam molding core material, wherein a raw material guide portion having a protrusion or a groove is formed in the vicinity of the injection port along the longitudinal direction of the core material.

A second aspect of the present invention is to attach a core material having an injection port to one mold surface having an injection nozzle insertion port, and to insert the core material through the injection nozzle insertion port and the injection port. In a method for producing a foam-molded article in which a liquid foaming raw material is injected into a cavity on one side and a foam produced is integrated with the core material, in the vicinity of the injection port on the foam side surface of the core material, The present invention relates to a method for producing a foam-molded article, characterized in that a raw material guide portion having a protrusion or a groove along the longitudinal direction is provided.

A third aspect of the present invention is a method for producing a foamed molded article in which a liquid foaming raw material is injected into a cavity through an injection port formed in one mold surface to foam, and the mold surface near the injection port is provided with: The present invention relates to a method for producing a foam-molded article, characterized in that a protruding or groove-shaped raw material guide portion is provided along the longitudinal direction of the mold surface.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a perspective view of a core material which is an embodiment of the first invention, FIGS. 2 to 6 show an example of a manufacturing method of the second invention, and FIG. 2 is a cross section of a mold used in the manufacturing method. FIG. 3, FIG. 3 is a plan view showing a mold surface on the side where the core material is attached in the mold, FIG. 4 is a plan view showing a state in which a liquid foaming raw material is injected from an injection port, and FIG. FIG. 6 is a plan view showing a state where the liquid foaming raw material flows along the raw material guiding portion, and FIG. 6 is a plan view showing a state where the liquid foaming raw material fills the cavity. FIG. 7 is a cross-sectional view of the foam-molded product obtained by the above manufacturing method. Further, FIG. 8 is a perspective view showing another example of the core material according to the first invention, FIG. 9 is a sectional view of a foam-molded article obtained by using the core material, and FIG. 10 is another example of the core material. FIG. 11 is a sectional view of a mold showing an example of a method for manufacturing a foam-molded article using the core material, FIG. 12 is a sectional view thereof, and FIG. 13 is a metal showing an example of the manufacturing method of the third invention. FIG.

As shown in FIG. 1, a foam molding core material 10 according to the first invention is made of metal, hard plastic, or the like molded into a predetermined core material shape. A filling port 11 and a raw material guiding part 12 are provided.

The injection port 11 is for guiding the liquid foaming raw material to one side of the core material at the time of molding, and is provided corresponding to the injection nozzle insertion port provided in the molding die.

Further, the raw material guiding section 12 is used for foam molding.
The liquid foaming raw material injected from the injection port 11 is smoothly and surely filled toward both ends in the longitudinal direction of the cavity, which is difficult to be filled due to an increase in viscosity of the liquid foaming raw material as the reaction proceeds. It is provided near the inlet 11 along the longitudinal direction of the core 10. In the present embodiment, the raw material guiding portion 12 is formed so that the surface of the core material on the side where the foam is formed has a projecting shape.

The raw material guiding part 12 is formed by the core material 1 described above.
In addition to a continuous shape on the 0 surface, an intermittent protrusion shape may be used. Further, the height of the raw material guiding part 12 is determined according to the height (thickness) of the foamed molded product manufactured by using the core material 10. It is preferable to set such that a gap remains between the surfaces. By doing so, it becomes possible to quickly fill the liquid foaming raw material not only in the longitudinal direction of the cavity but also in the lateral direction thereof, and in addition, a feeling of discomfort is generated on the surface of the foamed molded product corresponding to the raw material guiding portion 12. Nor.

2 to 6 show a method of manufacturing a foam molded article which is an embodiment of the second invention. In the figure,
Reference numeral 20 is a molding die, and the molding cavities 23 are constituted by the split dies 21, 22. As shown in FIGS. 2 and 3, an injection nozzle insertion port 24 is formed in one of the split molds 21 of the molding die 20, and an injection nozzle 25 for discharging the liquid foaming raw material into the cavity 23 is installed. It has become. The tip of the injection nozzle insertion port 24 opens into the cavity 23 as a gate 26.

The core material 10 is attached to the mold surface of the split mold 21 on the side where the injection nozzle insertion port 24 is formed by using a clip (not shown) provided on the mold surface. To be This core material 10 has been described above with reference to FIG. 1, and is attached so that the inlet 11 is aligned with the gate 26 and the raw material guiding part 12 is oriented so as to project toward the other split mold 22 side. . Further, in the present example, the skin 13 is arranged on the other split mold 22 mold surface on the side where the core material 10 is not set.

In this way, after the core material 10 is attached to the molding die 20, the split molds 21 and 22 are closed, and the core material 10 and the skin are removed from the injection nozzle 25 inserted into the injection nozzle insertion port 24. The liquid foaming raw material 15 is injected into the cavity 23 between the spaces 13.

Since the injection port 11 of the core material 10 is sandwiched between the raw material guiding part 12 and the cavity side surface 27 in the cavity 23, the liquid foam injected into the cavity 23 from the injection port 11 is formed. As shown in FIGS. 4 and 5, the raw material 15 is effectively guided along the raw material guiding portion 12 of the core material 10.

At this time, since the raw material guiding portion 12 is formed in the longitudinal direction of the core material 10, as shown in FIG. 6, the liquid foaming raw material 15 is quickly guided to the longitudinal end portion of the cavity 23. To be done. Therefore, even if the foamed product has a long shape, it is possible to uniformly fill the liquid foaming raw material into the cavity without providing a runner outside the cavity, and to prevent occurrence of wall thinning due to improper filling of the liquid foaming raw material. You can Moreover, since the liquid foaming raw material, which has been filled in the runner portion up to now, becomes unnecessary, the manufacturing can be extremely economical.

The injected liquid foaming raw material 15 is foamed and hardened between the core material 10 and the skin 13 to form a foam 14 covered with the skin 13 on one side of the core material 10. As shown in FIG. 7, the obtained foam-molded product 16 has an extremely good appearance without product defects such as lack of wall. Moreover, there is no portion corresponding to the runner portion as in the conventional case, and it is not necessary to perform the cutting work.

FIG. 8 shows another example of the core material of the present invention. Reference numeral 30 is a core material, and 31 is an injection port. In this example, in the longitudinal direction of the surface of the core material 30 on the side where the foam is formed, the raw material guiding portions 32, 32 are provided on both sides with the injection port 31 sandwiched therebetween. If the core material 30 is arranged in the molding die so that the raw material guiding parts 32, 32 are on the side where the foam is formed, the two raw material guiding parts 32, 32 are provided.
The injection port 31 is sandwiched by and the liquid foaming raw material injected from the injection port 31 can be efficiently guided in the cavity longitudinal direction. In particular, this embodiment can efficiently guide the liquid foaming raw material in the longitudinal direction of the cavity even when the distance between the inlet 31 and the side surface of the cavity (side surface along the longitudinal direction, which corresponds to 27 in FIG. 2) is large. There are advantages. FIG. 9 is a sectional view of a foam-molded product molded using this core material 30.
Reference numeral 40 in the figure is a foam molded product, and the same components as those in FIG. 7 represent the same members.

The raw material guide portions are not limited to the projecting shape protruding from the foam-side surface of the core material, and may be the groove shape recessed from the foam-side surface.

FIG. 10 shows a core material of still another example. In the longitudinal direction of the core material 40, a groove-shaped raw material guiding portion 42 which is recessed from the surface is formed on the surface on the foam side, and the injection port 41 is provided at a predetermined position on the raw material guiding portion 42. ing.

FIG. 11 shows a method of manufacturing a foam-molded article using this core material 40. As shown in the figure, the core material 40 is placed in one split mold 51 of the molding die 50. A concave portion 52 corresponding to the raw material guiding portion 42 of the core material 40 is provided at a predetermined position on the mold surface of the split mold 51, and the core material 40 is attached with the raw material guiding portion 42 fitted in the concave portion 52. To be Reference numeral 54 in the figure denotes an injection nozzle insertion port 5 of the molding die.
5 is an injection nozzle, 56 is a cavity 53 for liquid foaming raw material
A gate for discharging inside 57 is another divided type. This core material 40 is attached to the mold surface of the split mold 51, and the injection port 41
The liquid foaming raw material 15 is injected into the cavity 53 via. The liquid foaming raw material 15 is guided in the longitudinal direction of the cavity 53 along the raw material guiding portion 42 to fill the inside of the cavity. The obtained product is shown in FIG. The same effect can be obtained when a protruding raw material guiding portion is provided instead of the groove-shaped raw material guiding portion of this embodiment.

FIG. 13 shows an example of a method for producing a foam molded article according to the third invention, in which reference numeral 60 is a molding die, 61,
62 is the split mold, and 63 is a cavity formed between the split molds 61 and 62. This manufacturing method is suitable for molding a foam-molded article without using a core material, and one split mold 61 is provided with an injection nozzle insertion port 64, the tip of which serves as an injection port 66 on the mold surface of the split mold 61. It is open. An injection nozzle 65 for injecting the liquid foaming raw material into the cavity 63 is attached to the injection nozzle insertion port 64.

In the molding die, on the mold surface on the side where the injection port 66 is formed, in the vicinity of the injection port 66,
A protruding raw material guiding portion 67 along the longitudinal direction of the cavity 63
However, it is formed with a gap left between it and the facing mold surface 68. The liquid foaming raw material injected from the injection port 66 is
In the cavity 63, the material can be smoothly guided along the raw material guiding portion 67 in the longitudinal direction of the cavity.

Also in the third aspect of the invention, the raw material guiding part 67 is appropriately formed into a grooved shape, as shown in FIG.
Two raw material guiding parts similar to the raw material guiding parts 32, 32 formed on the core material 30 of FIG. 10 are provided with the mold surface injection port 67 sandwiched therebetween, or the same as the raw material guiding part 42 formed on the core material of FIG. A raw material guiding part is provided at the position of the injection port 66 on the mold surface. Even in those cases, the liquid foaming raw material can be efficiently guided in the longitudinal direction in the cavity, and the obtained foamed molded article does not have a portion corresponding to the runner portion, which saves the liquid foaming raw material and cuts the runner portion. Omission can be realized.

[0028]

As shown and described above, according to the core material for foam molding and the method for manufacturing a foam molded article of the present invention,
Since the liquid foaming raw material injected into the cavity flows in the cavity longitudinal direction along the raw material guiding portion provided on the core material or the raw material guiding portion provided on the mold surface, even if a runner is not provided outside the cavity, It is possible to reliably fill the liquid foaming raw material into the cavity. Therefore, the liquid foaming raw material that has conventionally filled the runner part is not necessary, and not only the material cost can be suppressed, but also the work of cutting and removing the runner part after manufacturing the foamed molded product is not necessary. Manufacturing costs can be reduced. Moreover, the foam-molded product obtained has no flesh or the like and is extremely excellent in quality.

Conventionally, in such foam-molded articles, ribs or the like were often provided in the core material in order to secure the strength of the product. However, if the core material provided with the raw material guiding part in the present invention is used, The strength of the product can be increased similarly to the rib.

[Brief description of drawings]

FIG. 1 is a perspective view of a core material that is an embodiment of the first invention.

FIG. 2 shows an example of a manufacturing method of the second invention, and is a cross-sectional view of a mold used in the manufacturing method.

FIG. 3 is a plan view showing a mold surface on a side to which a core material is attached in the mold.

FIG. 4 is a plan view showing a state where a liquid foaming raw material is injected from an injection port.

FIG. 5 is a plan view showing a state where the injected liquid foaming raw material flows along a raw material guiding part.

FIG. 6 is a plan view showing a state where the cavity is filled with the liquid foaming raw material.

FIG. 7 is a cross-sectional view of a foam-molded article obtained by the manufacturing method.

FIG. 8 is a perspective view showing another example of the core material according to the first invention.

FIG. 9 is a cross-sectional view of a foam-molded article obtained by using the core material.

FIG. 10 is a perspective view showing another example of the core material.

11 is a mold cross-sectional view showing an example of a method for manufacturing a foam-molded article using the core material of FIG.

FIG. 12 is a sectional view thereof.

FIG. 13 is a mold cross-sectional view showing an example of the manufacturing method of the third invention.

FIG. 14 is a perspective view showing an example of a general foam-molded article for an instrument panel.

FIG. 15 is a sectional view thereof.

[Explanation of symbols]

 10 Core Material 11 Injection Port 12 Raw Material Induction Section 13 Skin 14 Foam 15 Liquid Foaming Raw Material 20 Mold 21 Split Mold 22 Split Mold 23 Cavity 24 Injection Nozzle Insertion 25 Injection Nozzle

Claims (3)

[Claims] 1. A foam molding core material having an injection port at a predetermined portion and injecting a liquid foaming raw material from the injection port to form a foam on one side, wherein the pouring on the foam side surface of the core material A foam molding core material, characterized in that a raw material guiding portion having a protrusion or a groove is formed near the inlet in the longitudinal direction of the core material. 2. A core material having an injection port is attached to one mold surface having an injection nozzle insertion port, and a liquid is provided in a cavity on one side of the core material through the injection nozzle insertion port and the injection port. In a method for producing a foam-molded article in which a foaming raw material is injected and a foam produced is integrated with the core material, a protrusion along the longitudinal direction of the core material is provided in the vicinity of the injection port on the foam side surface of the core material. A method for producing a foam-molded article, characterized in that a groove-shaped raw material guiding part is provided. 3. A method for producing a foam-molded article in which a liquid foaming raw material is injected into a cavity through an injection port formed in one mold surface to foam, wherein the mold surface near the injection port has a longitudinal direction of the mold surface. A method for producing a foam-molded article, characterized in that a raw material guide portion having a projection or a groove along the direction is provided.