JPH10155519A - Production of foamed insole of shoes - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing foamed insoles of shoes with less material consumption and simple stages. SOLUTION: One long and flat mixed material plate 20 is formed by mixing materials contg. ethylene vinyl acetate copolymer of a prescribed compsn., a foaming agent and a cross-linking agent and agitating the mixture, then rolling the mixture with a calender. This mixed material plate 20 is cut to a size reducing the insole size to be produced at a prescribed ratio by a cutting machine to form an insole prototype 20. This insole prototype 22 is directly placed into one set of molds kept at 180 deg.C and is foamed by heating, by which the foamed insole is produced.

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 kind of insole of ethylene vinyl acetate and a border thereof, and it rolls ethylene vinyl acetate and a foamed mixed material into one long flat plate, The present invention relates to a method for producing a foamed insole, which is cut to a predetermined reduction ratio, and is further subjected to heat foam molding to complete a foamed insole.

[0002]

2. Description of the Related Art In general, the sole of an athletic shoe is formed by bonding an insole formed of an ethylene vinyl acetate foam material layer to an outsole formed of a rubber material layer having wear resistance. The ethylene vinyl acetate foam layer used as this insole has relatively good elasticity and toughness,
A predetermined ratio of ethylene vinyl acetate, a CAP foaming agent and a DCP cross-linking agent, etc. are mixed, stirred, and heated to form an elastic foam material layer, which is used for an insole and comfortably worn on a foot. It provides a feeling and has an elastic vibration absorbing effect.

[0003] However, in the insole of the well-known athletic shoe, a defect is easily generated at a joint portion between the insole and a land provided on the outer periphery of the insole, and the manufacturing cost is increased. For a well-known method of manufacturing an insole and its structure, refer to Taiwan Patent No. 157875, entitled "Contour Structure with Accurately Embossed Multicolored Convex Sides of Foam Insole". The features of the manufacturing technology are shown in FIGS. 1 to 3. In this technology, a foam material base plate is cut at a predetermined angle by a plurality of cutters to form a relatively thick heel portion and a relatively thin sole portion. After that, the foamed material plate 10 was further punched by a press to form an insole prototype having a predetermined dimension, and further formed into a wedge-shaped insole shape through a number of cutting steps. Further, the lands 15 are bonded after polishing the periphery of the insole 12 thus formed. In this technique, the cutting of the insole prototype, and then the cutting to form a wedge-shaped insole, and the subsequent polishing process, generated a large amount of waste, wasted a lot of material, and costly to dispose of the waste. In addition, during the cutting and polishing processes, the molded film layer of the foamed insole plate was destroyed, and the relatively good physical properties, toughness and tensile strength of the molded film layer were lost. In this way, the technique takes time and effort in the cutting and polishing process, increases the manufacturing cost, does not provide high quality products,
It had no industrial utility value. Further, the insole 12 according to this technique does not have an embossed pattern formed by integral foam molding, and the periphery of the upper surface of the insole 12 is not a right-angled arc-shaped connecting edge. None of them could be joined flat with the shell, and it was hard to say that it had industrial utility value.

[0004]

The well-known manufacturing method of punching a foam material plate with a press is intended to solve the problem of breaking the insole foam layer in the process of cutting and polishing the periphery. The present invention provides a manufacturing method in which an unfoamed mixed material plate is first cut to a reduced ratio to obtain an insole prototype, and subjected to a single foam molding to complete a foamed insole. An object of the present invention is to protect the coating layer of the foamed insole by eliminating the process of cutting and polishing the material and to protect the physical properties, toughness and tensile strength of the insole structure. Further, the present invention provides
Providing a manufacturing method that can produce insole products with only one molding die and one molding process, which not only reduces the amount of waste but also reduces the manufacturing cost of the mold,
It is another object of the present invention to eliminate waste of energy caused by cooling and heating in a mold many times. And furthermore, the present invention fully utilizes the cutting waste of the material plate, and adds it to the heel portion of the insole prototype to increase the thickness of the portion after foaming, thereby reducing the waste material plate. The task is to reduce and use resources effectively.

[0005]

The invention according to claim 1 is a method for producing a foamed insole for shoes, comprising mixing a predetermined distribution of ethylene vinyl acetate, a material containing a foaming agent and a crosslinking agent, Stir and then roll it with a calender to form one long flat mixed material plate, cut this mixed material plate into dimensions in which the insole dimensions produced by the cutting machine are reduced by a predetermined ratio, and form the insole prototype The insole prototype is directly placed in a set of molding dies at 180 ° C. and heated and foamed to form a foamed insole. Simultaneously with the heated foaming, a curved portion having an embossed pattern around the foamed insole or a predetermined radian is formed. In addition to the above, a connecting edge is formed around the upper surface of the foam insole to protrude in a ring shape, and the land is in close contact with the outside of the foam insole and the connecting surface to facilitate bonding. Wherein the is a method for producing a foamed insole of the shoe.

According to the invention of claim 2, when the front end and the rear end of the insole mold cut to the reduced size are the same in thickness, before the insole mold is placed in the mold for heating and foaming, The method for producing a foamed insole for a shoe according to claim 1, wherein an appropriate amount of waste generated when the insole prototype is cut from the mixed material plate is added.

A third aspect of the present invention provides a reduced-size insole prototype obtained by mixing and stirring ethylene vinyl acetate and a mixed material into pellets, and then integrally injection-molding with a foam injection molding machine. Subsequently, the insole prototype is heated and expanded integrally under heat and pressure to form a foamed insole product, and at the same time, the periphery of the foamed insole product is made to be easily bonded to a land. I have.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a predetermined distribution of ethylene vinyl acetate and a foamed mixed material are mixed and stirred,
Rolled into one mixed material plate, and the unfoamed mixed material plate is cut into dimensions in which the insole dimensions to be manufactured are reduced at a predetermined ratio to form an insole prototype, and the insole prototype is formed into one molding die. Placed in a mold and heated and foamed to form a foamed insole, but in order to make the insole prototype relatively thick at the completion of foaming, for example, having a wedge-shaped heel portion, in the heel portion of the cut insole prototype,
A scrap material obtained by cutting a fixed amount of the material plate is added, or the insole prototype is cut directly, for example, on a wedge-shaped material plate, thereby forming a relatively thick insole prototype having, for example, a wedge-shaped heel portion. In the present invention, a foamed insole with a good feeling of wearing is manufactured, and in the present invention, an arc-shaped connecting edge is provided by foam molding around the upper surface of the insole to be manufactured. I have.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS For the production flow chart of the present invention and the resulting foamed insole product, please refer to FIGS. In the present invention, first, a predetermined distribution of ethylene vinyl acetate, a foaming agent, and mixing a material containing a crosslinking agent,
The mixture is stirred and then rolled by a calender to form one long flat mixed material plate 20. The unfoamed mixed material plate 20 is further cut to a size obtained by reducing the insole size manufactured by a cutting machine at a predetermined ratio. Then, the insole prototype 22 was placed in one molding die and heated and foamed to form a foamed insole. After the insole prototype 22 was foam-molded, the heel portion thereof was, for example, wedge-shaped. In order to make the insole mold 22 relatively thick, a fixed amount of waste material generated when the insole mold 22 is cut from the mixed material plate 20 is added to the heel portion of the cut insole mold 22 or directly mixed, for example, in a wedge shape. Material plate 20
More insole prototypes are cut so that the foamed insole at the time of completion of foaming has a relatively thick heel portion. The insole prototype 22 thus manufactured is placed in a 180 ° C. high-temperature molding die, and foamed. To obtain 25 products of foamed insoles. According to the method of the present invention, a curved portion having a predetermined radian is formed at an appropriate position on the periphery and the bottom surface of the foam insole 25 at the same time as the foam molding. Does not require a step to format. In addition, a connecting edge 252 projecting annularly around the upper surface of the foam insole 25 is formed, and a single smooth arc surface is formed between the foam insole 25 and the connecting edge 252. The lands 30 are easily adhered to the side surfaces by closely attaching them. The land 30 encloses a side surface of the foam insole 25 and a connecting surface of shoe cloth or shoe leather (not shown). At an appropriate position on the bottom surface of the foam insole 25, an outsole having abrasion resistance is bonded. In another preferred embodiment of the present invention, a mixture obtained by mixing and stirring ethylene vinyl acetate and the mixed material is first granulated into pellets, and further molded integrally with a foam injection molding machine to form a reduced-size insole prototype. Subsequently, the insole prototype is heated and thermally expanded integrally to form a foamed insole 25. The periphery of the foamed insole 25 is made to easily adhere the land 25. In the present invention, the insole prototype having a reduced ratio is manufactured by a method of cutting a mixed material plate or a method of foaming and injection-molding foam pellets. Need not be
Therefore, the coating layer of the foamed insole 25 can be protected, and the physical properties, toughness, and tensile strength of the insole structure can be improved.

[0010]

In summary, the present invention undoubtedly improves upon the above-mentioned disadvantages of the known art.
In the present invention, there is no need to further cut and grind the periphery of the insole after the foam molding, and because it is manufactured by one-time heating and pressing in a mold, there is no waste of energy. An embossed pattern or a curved portion having a predetermined radian can be simultaneously formed at the time of the foam molding, so that the industrial use value of the foam insole can be enhanced.

[Brief description of the drawings]

FIG. 1 is a perspective view of a stamped foam insole prototype and a land in the manufacturing method of Taiwanese Patent No. 157875, which is a known technique.

FIG. 2 is a diagram showing a punched state of the foamed insole prototype of FIG. 1 from a foamed material plate.

FIG. 3 is a sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is a manufacturing flowchart of the embodiment of the present invention.

FIG. 5 is a view showing a situation where an insole prototype having a reduced ratio is cut from the material plate of the present invention.

FIG. 6 is a perspective view of a foam insole and a land according to the present invention.

FIG. 7 is a manufacturing flowchart of another preferred embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 20 mixed material plate 22 insole prototype 25 foamed insole 252 connecting edge 30 land

Claims (3)

[Claims] 1. A method for producing a foamed insole for shoes, comprising mixing and stirring a predetermined distribution of a material including ethylene vinyl acetate, a foaming agent, and a crosslinking agent,
Rolled by a calender to form one long flat mixed material plate, cut this mixed material plate into dimensions in which the insole dimensions to be manufactured by the cutting machine are reduced at a predetermined ratio, and make the insole prototype, and make this insole prototype In addition to forming a foamed insole by directly placing in a set of molding dies at 180 ° C. to form a foamed insole, and simultaneously forming a curved portion having an embossed pattern or a predetermined radian around the foamed insole, A method for manufacturing a foamed insole for shoes, characterized in that a connecting edge protruding annularly around the upper surface of the foamed insole is formed so that a land is closely attached to the outside of the connecting surface with the foamed insole to facilitate bonding. 2. When the front end and the rear end of the insole mold cut to a reduced size are the same in thickness, before the insole mold is placed in a molding die for heating and foaming, the insole mold is insulated from one side edge of the insole mold by a mixed material plate. The method for producing a foamed insole for a shoe according to claim 1, wherein an appropriate amount of waste generated when the prototype is cut is added. 3. A mixture obtained by mixing and stirring ethylene vinyl acetate and a mixed material is first granulated into pellets, and then integrally injection-molded with a foaming injection molding machine to form a reduced-size insole prototype. A method for producing a foamed insole for shoes, wherein a prototype is heated and thermally expanded integrally to form a foamed insole product and, at the same time, the periphery of the foamed insole product is easily bonded to a land.