JP3046596U - Core material for footwear soles - Google Patents

Abstract

(57) [Summary] [Problem] To provide a footwear sole core material which is lightweight, has cushioning properties, has little risk of breakage, and has a strong adhesive force of an exterior material. SOLUTION: A bottom wall 6, an upper wall 7 and a peripheral wall 8 are integrally formed by blow molding using ABS resin or PVC as a material, and a buffer space 9 surrounded by these walls is provided. Since it is formed into a hollow shape by blow molding, it is lightweight and has cushioning properties. Also, due to its material, there is little risk of breakage due to impact. Further, the adhesive strength of the exterior material is strong, and the attaching operation is easy, and the production efficiency is improved.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 This invention mainly relates to a core material of a shoe sole used for sandals.

[0002]

[Prior art]

 BACKGROUND ART Conventionally, as a core material of a sandal bottom, one made of expanded styrene, expanded polyurethane, expanded EVA, or the like has been used. However, foamed styrene is liable to crack or chip during transportation between processes, and other materials have disadvantages such as poor adhesion of exterior materials such as leather.

[0003] Further, there is also a material formed by injection molding using an ABS resin as a material. However, in this case, since it cannot be formed into a hollow shape, there is a problem that the material becomes heavy and the cushioning property cannot be obtained.

[0004]

[Problems to be solved by the invention]

 In view of the above, the present invention aims to provide a core material for a shoe sole that is lightweight, has cushioning properties, has a high adhesive strength of an exterior material, and has a low risk of breakage.

[0005]

[Means for Solving the Problems]

 In order to solve the above problems, the core material of the shoe sole according to the present invention is made of ABS resin or PVC, and the bottom wall, the upper wall and the peripheral wall are integrally formed in the core material of the shoe sole formed by blow molding. In addition to this, a structure was adopted in which a buffer space surrounded by each of these walls was provided.

[0006] Since this core material is formed into a hollow by blow molding, it is lightweight and has a cushioning property, and its material is also less likely to be damaged by impact. Furthermore, the adhesive strength of the exterior material is strong, and the attaching operation is easy, and the production efficiency is improved.

[0007] In addition, in the case where a support is provided between the bottom wall and the upper wall, excessive bending of the upper wall is suppressed by the support, and the support is less likely to break.

[0008]

[Embodiment of the invention]

 1 and 2 show a footwear S using the core material 1 according to the present invention. In this footwear S 1, a leather 2 is adhered to an outer peripheral surface of a core material 1, a rubber sole 3 is adhered to a bottom surface, and an insole 5 is laid on an upper surface with a lower part of an upper 4 interposed therebetween.

As shown in FIGS. 3 to 5, the core material 1 has a bottom wall 6, an upper wall 7, and a peripheral wall 8 integrally formed, and a buffer space 9 is provided therein. . Also, between the bottom wall 6 and the upper wall 7, three columns 10 arranged in front and rear are provided.

As a material of the core material 1, an ABS resin (acrylonitrile / butadiene / styrene copolymer) or PVC (vinyl chloride resin) is used, and a blow molding (space molding) method is employed as a molding method.

At the time of molding, first, as shown in FIG. 6, a pellet 12 of ABS resin or PVC is charged as a raw material into a hopper 11 of an extruder P, and the pellet 12 is heated while rotating a screw 13 forward. It is melted and extruded from the die 14 as a cylindrical parison 15.

Then, a pair of molds 16 approach the parison 15 from both sides. Here, each mold 16 is provided with a cavity 17 obtained by dividing the core material 1 into upper and lower parts, and three tapered pins 18 are provided on the bottom surface of the cavity 17.

Subsequently, as shown in FIG. 7, a hollow needle 19 is inserted into the parison 15 while sandwiching the parison 15 between the pair of dies 16, and the dies 16 are brought into close contact with each other. When air is blown into the son 15, the parison 15 expands and comes into close contact with the inner surface of the cavity 17 as shown in FIG. At this time, the column 10 is formed by the parison 15 closely contacting the periphery of the taper pin 18. Thereafter, the pair of molds 16 are separated from each other, and burrs are removed to finish the mold into a predetermined shape. The tips of the tapered pins 18 are closely opposed to each other when the mold is clamped, and are easily pulled out of the support 10 due to the tapered shape when the mold is opened.

The above-mentioned core material 1 has a thin hollow structure, so that it is lightweight and has excellent cushioning properties. And because of its excellent impact resistance, there is little risk of damage due to impact during transportation. In addition, the adhesive strength of the exterior material is strong, and the work of attaching the exterior material is easy, and the production efficiency is improved. Furthermore, the support 10 suppresses excessive bending of the upper wall 7 and is less likely to break.

When the taper pin 18 is omitted from the mold 16 as shown in FIG. 9, when the core 1 is formed, the support 10 is not formed on the core 1 as shown in FIG. By making the wall thickness sufficient to receive the load, the strength can be secured.

In FIG. 9, a hollow needle 19 is inserted into the parison 15 from the side, and the parison 15 is held by the needle 20 from above when the mold is opened. When the buffer space 9 is sealed by sealing the extraction hole 21 of the hollow needle 19 shown in FIG. 10, excellent cushioning properties can be obtained.

[0017]

[Effect of the invention]

 As described above, since the core material according to the present invention is formed to be hollow by blow molding, it is lightweight and has excellent cushioning properties. Also less. Further, the adhesive strength of the exterior material is strong, so that the attaching operation is easy, the production efficiency is improved, and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view of a sandal using a core material according to the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a cross-sectional plan view of the core material according to the first embodiment.

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3;

FIG. 5 is a sectional view taken along the line VV in FIG. 3;

FIG. 6 is a schematic view showing a manufacturing process of the core material according to the first embodiment.

FIG. 7 is a schematic view showing a manufacturing process of the core material of the above.

FIG. 8 is a schematic view showing a manufacturing process of the core material of the embodiment.

FIG. 9 is a schematic view showing another manufacturing process of the core material.

FIG. 10 is a longitudinal sectional side view of a core material manufactured in the same process.

[Explanation of symbols]

 S Footwear P Extruder 1 Core material 2 Leather 3 Rubber bottom 4 Upper 5 Insole 6 Bottom wall 7 Top wall 8 Perimeter wall 9 Buffer space 10 Post 11 Hopper 12 Pellet 13 Screw 14 Die 15 Parison 16 Mold 17 Cavity 18 Taper pin 19 Hollow needle 20 Needle 21 Extraction hole

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B29L 31:50

Claims (2)

[Utility model registration claims] 1. A footwear sole core material made of ABS resin or PVC and formed by blow molding, wherein a bottom wall, an upper wall and a peripheral wall are integrally formed, and a buffer space surrounded by each of these walls. The core material of the footwear sole provided with. 2. The footwear sole core material according to claim 1, wherein a support is provided between the bottom wall and the upper wall.