JPH0430841B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to the bonding of shoe soles, particularly shoe soles made by bonding an insole made of vulcanized rubber sponge to a pre-formed outsole made of thermoplastic plastic. This invention relates to a molding method and apparatus.

BACKGROUND TECHNOLOGY The soles of golf shoes and other athletic shoes, for example, in which spikes are integrally embedded, are made of a sole that is injection molded in advance from a thermoplastic plastic material (the spikes are embedded in this sole). In some cases, a rubber sponge insole is glued to provide cushioning properties.

Conventionally, such soles have been produced by buffing and buffing the bonding surfaces of a pre-formed outsole and a sponge material for the insole cut into a predetermined shape from a raw material sponge sheet of a predetermined thickness. After applying the primer treatment, apply a solvent-volatile adhesive once or twice, let it dry for a while, heat it, heat activate it, and then glue the two together. After crimping, the insole is shaped into the desired shape. It had been buffed.

Problems to be Solved by the Invention However, the finishing process of the above-mentioned insoles is often done by hand by buffing, which is time-consuming and increases manufacturing costs, as well as rounding of the heel. There was a problem in that it required skill to finish complex shapes such as the taper of the arch of the foot.

The present invention was made in view of the current situation, and it simplifies the bonding process of the pre-formed outsole and the insole and the process of forming the insole, improving work efficiency and greatly reducing manufacturing costs. The technical challenge is to reduce the width.

Means for Solving the Problems The first aspect of the invention is to fit and hold a pre-formed thermoplastic bookbinding bottom into a fitting recess of a lower die made of a material with low thermal conductivity, while maintaining a predetermined size. A molded material for the inner sole made of vulcanized rubber sponge is fitted and held in a molded recess of an upper mold made of a material with high thermal conductivity, and the outsole and the molded element are brought into contact with each other. After applying adhesive treatment to the surfaces, the upper mold and the lower mold are overlapped, heated for a predetermined period of time, and then cooled to melt the molding material and form the jointed midsole, while at the same time molding the jointed midsole. It is characterized in that it is adhered to the outsole.

A second invention comprises: a lower mold provided with a fitting recess for fitting and holding a pre-formed thermoplastic plastic binding bottom; an upper mold provided with a molding recess for molding the mating bottom; the lower mold; A shoe sole adhesive molding device comprising a pressure plate that heats and cools the upper molds by applying pressure in a stacked state, and a heating and cooling device for the pressure plate, wherein the lower mold is made of a material with low thermal conductivity. The upper die is made of a material with high thermal conductivity.

Function The sole, which is fitted and held in the lower mold, is heated to a surface temperature of 100°C or less to prevent the pre-formed design from deforming due to heat. On the other hand, the molding material for the insole accommodated in the molding recess of the upper mold is heated and melted and compression molded into a predetermined shape by the molding recess, so it varies depending on the material, but at a temperature of about 100°C to 130°C.
It is heated for a second and is bonded to the outsole at the same time as it is molded.

The heating temperature difference between the outsole and the molded material for the midsole described above is achieved by making the thermal conductivity of the upper mold and the lower mold different. That is, the upper mold is made of aluminum with high thermal conductivity, and the lower mold is made of a resin material with low thermal conductivity, such as a two-component curing polyurethane resin. In this case, it is preferable to surround the lower die with a highly rigid metal frame. In addition, the lower mold is made of aluminum alloy like the upper mold, and the space between the lower mold and the heating press plate is made of an insulating material with low thermal conductivity and excellent heat resistance, such as felt-like carbon fiber. Appropriate cooling may be achieved by interposing an underlay or by providing cooling piping in the lower mold.

Embodiments Hereinafter, embodiments of the present invention will be described based on the drawings. FIG. 1 shows a pre-formed outsole 1 used in carrying out the present invention and a molded material 2 for an insole molded to predetermined dimensions as will be described later.

The outsole 1 is pre-injection molded from a thermoplastic material such as 11 nylon or 12 nylon plasticizer grade, polyamide elastomer, polyester elastomer or thermoplastic polyurethane, and at the same time has spikes 3 embedded therein.
Further, the adhesive surface 4 is subjected to a predetermined adhesive treatment, for example, a solvent-volatile adhesive 5 is applied and dried.
In addition, 11 nylon, 12 nylon,
When using a material with poor adhesion such as polyamide elastomer, it is desirable to insert mold the adhesive surface 4 with artificial leather, fabric, nonwoven fabric, etc. with good adhesion.

The molding material 2 for the insole is cut into a predetermined shape from a sheet material of polybutadiene-based (RB-based) or ethylene vinyl acetate-based (EVA-based) vulcanized rubber sponge. Molding material 2 for the insole
In order to make it lighter and retain flexibility, the foaming rate is increased to have a specific gravity of approximately 0.10 to 0.45 before molding, and its thickness t is as shown in Figures 1 and 5.
The depth t of the molding recess 21 of ₀ is approximately 1.2 to 2.0 times,
In the width direction, as shown by the imaginary line in FIG. 4, the mold is shaped to have approximately the same contour shape as the molding recess 21. As with the outsole 1, the adhesive surface 6 of the molded material 2 for the insole is also subjected to a predetermined adhesive treatment, for example, a solvent-volatile adhesive 5 is applied and dried.

FIGS. 2 and 3 show a lower mold 10 equipped with a fitting recess 11 for fitting and holding the outsole 1, and the lower mold 10 is made of a resin material having a lower thermal conductivity than a metal material, For example, it is made of a two-component curing polyurethane resin, and is surrounded by an aluminum alloy frame 12 to maintain rigidity during press molding. The fitting recess 11 has the same design as the back surface of the outsole 1 in order to hold the outsole 1 in a correct posture.

The upper mold 20, as shown in FIGS. 4 and 5,
It has a molded recess 21 for molding the inner sole, and is entirely made of an aluminum alloy with high thermal conductivity. In the illustrated embodiment, the molded recess 21 has a shape in which the toe part 22 and the heel part 23 are deeply recessed, but it is possible to design it into any desired shape to some extent.

Next, an adhesive molding process using the lower mold 10 and the upper mold 20 will be explained.

First, the pre-formed outsole 1 shown in FIG. After the alignment, the upper mold 20 is superimposed on the lower mold 10 and the adhesive surfaces 4 are subjected to the adhesive treatment 5,
6 to face each other. Lower mold 1 stacked like this
0 and the upper die 20 are held in a pressurized state by being sandwiched between pressure plates 30, 30 from both upper and lower sides, as shown in FIG.
Since this pressurizing plate 30 is a well-known and commonly used device in the technical field of shoe sole manufacturing, a detailed explanation will be omitted, but a heat medium such as steam and heating oil or a coolant such as cooling water circulates inside the press plate 30. A pipe line is provided, and heating or cooling is performed by supplying a heat medium or a refrigerant by operating a switching valve 31.

When the lower mold 10 and upper mold 20 stacked together are pressurized by the heated pressure plates 30, 30, the inner main sole 1 is heated by the heat transmitted from the pressure plate 30 through the upper and lower molds 10, 20. Insole molding material 2
is heated. In this heating process, the upper mold 20
The temperature of the adhesive surface 4 of the outsole 1 in the lower mold 10, which has a lower thermal conductivity, is controlled to be 100° C. or less to prevent the design of the molded outsole 1 from deforming due to heat. There is. On the other hand, since the upper mold 20 is made of an aluminum alloy with high thermal conductivity, the internal molding material 2 for the insole is approximately 110 mm, although it varies depending on the material.
The material 2 is heated to a temperature between 130° C. and 130° C., becomes semi-molten, and combined with the pressure applied by the pressure plate 30, the semi-molten molding material 2 forms a molding recess 21 as shown in FIG.
At the same time, the adhesive surface 6 of the outsole 1 is adhered to the adhesive surface 4 of the outsole 1. It is sufficient for this heating time that the temperature in the semi-molten state is maintained for about 10 seconds.

Next, a refrigerant is supplied to the pressure platen 30 to cool the lower mold 10 and the upper mold 20. In this cooling process, if there is a large temperature difference between the outsole 1 and the compression-molded insole 2a, deformation such as warping will occur after adhesive molding, so the surface temperature of the outsole 1 should be kept below 50°C. At the same time as cooling, the surface temperature of the formed inner sole 2a is lowered to 30
Cooling is controlled to a range of ~40°C.

After the above cooling step is completed, the lower mold 10 and the upper mold 20 are separated, and the sole 7 on which the outsole 1 and the midsole 2a are adhesively molded is removed from the mold. The sole 7 thus obtained can be finished as a finished product simply by cutting off the burrs generated on the periphery of the midsole 2a, and does not require manual finishing by buffing as in the past.

In the embodiment described above, the lower mold 10 is made of a rigid resin having a lower thermal conductivity than metal materials, but the lower mold 10 is made of aluminum alloy like the upper mold 20, and there is a cooling device inside the mold. The upper mold 20 may be heated to a temperature lower than that of the upper mold 20 by providing a cooling structure by providing piping. Moreover, between the lower die 10 made of aluminum alloy and the pressure plate 30,
The lower mold 10 is connected to the upper mold 2 by interposing an underlay plate made of a heat insulating material with low thermal conductivity and excellent heat resistance, such as felt-like carbon fiber.
It may be heated to a temperature lower than 0. However, the lower mold 10 made of two-component curing polyurethane resin explained in the above embodiments is not only inexpensive to manufacture, but also has some rubber elasticity.
There is an advantage that the adhesively molded sole 7 can be easily removed from the mold.

Effects of the Invention As explained above, according to the present invention, during the heating process, the molded outsole fitted to the lower mold keeps the heating temperature low to avoid deformation and other adverse effects due to heat, while at the same time The fitted insole forming material is heated to a moldable temperature, melting the forming material and forming the insole, and at the same time,
Since it is bonded to the outsole, it is ideal for manufacturing soles such as golf shoes where spikes or the like are integrally embedded in the outsole, improving work efficiency and greatly reducing manufacturing costs.

According to the second aspect of the present invention, the adhesive molding method described above can be easily carried out using simple equipment.

[Brief explanation of drawings]

The drawings show embodiments of the present invention, and FIG. 1 is a perspective view of a molded material for the outsole and midsole used in carrying out the present invention, FIG. 2 is a plan view of the lower mold, and FIG. 3 is the second view. No. 3
4 is a plan view of the upper mold, FIG. 5 is a sectional view taken along line 5-5 in FIG. 4, and FIG. 6 is a vertical sectional view of main parts showing the adhesive molding process. FIG. 7 is a schematic explanatory diagram of a heating and cooling device in adhesive molding. 1... Outsole, 2... Molded material for the insole, 2a... Molded insole, 3... Spike, 4, 6... Adhesive surface,
5... Adhesive, 7... Adhesively molded shoe sole, 10... Lower mold, 11... Fitting recess, 12... Frame, 20... Upper mold,
21... Molding recess, 30... Pressing plate.

Claims (1)

[Claims] 1. A pre-formed thermoplastic bookbinding bottom is fitted and held in a fitting recess of a lower mold made of a material with low thermal conductivity, while the vulcanization is molded to a predetermined size. A molded material for the inner sole made of rubber sponge is fitted and held in a molded recess of an upper mold made of a material with high thermal conductivity, and an adhesive treatment is applied to the opposing surfaces of the outsole and the molded material. After that, the upper mold and the lower mold are overlapped and heated for a predetermined period of time and then cooled to melt the molding material and form a mated insole, and at the same time adhere the mated midsole to the outsole. An adhesive molding method for shoe soles characterized by: 2. The adhesive molding method for a shoe sole according to claim 1, wherein spikes are embedded in the outsole. 3. A lower mold provided with a fitting recess for fitting and holding a pre-formed thermoplastic plastic book binding bottom; an upper mold provided with a molding recess for molding the bottom; the lower mold and the upper mold are overlapped. A shoe sole adhesive molding device comprising a pressure plate that heats and cools the press in a pressed state, and a heating and cooling device for the pressure plate, wherein the lower mold is made of a material with low thermal conductivity, and A shoe sole adhesive molding device, wherein the upper mold is made of a material with high thermal conductivity. 4. The shoe sole adhesive molding device according to claim 3, wherein the lower mold is made of a two-component curing polyurethane resin, and the upper mold is made of an aluminum alloy.