JPH0116162B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method of manufacturing shoes, and more particularly to a method of manufacturing shoes having a two-layer sole.

(Prior Art) Athletic shoes, especially various types of jogging shoes, have a double-layered sole, such as a midsole, to cushion the impact from the ground and protect the feet when landing. It's going around.

On the other hand, from the standpoint of fashionability, there are also shoes that use different materials for each layer of the sole and are colored to create a design effect.

As a conventional method for manufacturing soles of this kind of double-soled shoes, for example, as shown in FIG. 5, a dummy bottom 15 having a specific shape is used in a bottom mold for injection filling of sole material, For example, a gap 16 corresponding to a midsole is formed by the last 1 and the dummy bottom 15, and injection molding is performed, and then the dummy bottom 15 is replaced with a bottom mold 3 for forming a regular sole, and the outsole is injection molded.
It is manufactured.

In addition, a method for manufacturing shoes with multilayer soles that does not use the above-mentioned dummy bottom has recently been developed (Japanese Patent Publication No. 58082/1982), but such a method is, for example, as shown in FIG. A first step of forming a first molded shoe by providing a protrusion 17 on the last 1 and injection molding a first sole material into one space 18 divided into two by the protrusion. and,
This method includes a second step of lowering the bottom mold 3 and injecting a second bottom material into the space 19 formed.

(Problems to be Solved by the Invention) However, in such conventional manufacturing methods, for example, in the former method, it is insufficient to ensure complete adhesion between the last bottom stepping portion 20 and the dummy bottom 15. Therefore, when the Midsole molding material is injected and filled into the void corresponding to the Midsole,
Due to the filling pressure, the molding material not only fills the void 16 corresponding to the midsole, but also flows into the toe molding void 21, which inevitably increases the weight and makes the toe part soft, causing physical damage. Problems arose in that a shoe sole having the desired hardness could not be obtained, and there was also the inconvenience of having to quantify the amount of injection each time the dummy bottom was replaced.

Furthermore, from the perspective of the manufacturing process, the dummy bottom used to mold the midsole had to be replaced when molding the outsole, which was cumbersome, making it not necessarily an excellent manufacturing method.

In addition, in the latter method, since a protrusion is provided on the bottom of the last, a recess is formed in the midsole of the shoe, that is, the contact surface, which inevitably impairs the comfort of the shoe. It has points. Furthermore, since a protrusion is provided on the upper edge of the inner periphery of the side mold, there are also disadvantages such as restrictions on the design of the sole.

The present inventor has solved the above-mentioned problems, for example, the midsole molding material that becomes part of the sole can be injected and filled only into the gap corresponding to the midsole without flowing into the toe area, and the position and filling amount of the midsole can be made variable. We investigated a method for molding a two-layer shoe sole that is preferable in terms of appearance, which makes it possible to reduce weight, ensure the boundary line between the midsole and the outsole, which is located on the outside of the midsole and forms part of the sole of the shoe, and developed the present invention. It was completed.

Furthermore, the present invention also provides a method for manufacturing a shoe having a two-layered sole that is superior in design, allowing injection molding of, for example, different types of two-color soles at arbitrary positions on the sole.

(Means for Solving the Problems) In other words, the shoe manufacturing method of the present invention includes sequentially applying a primary molding material and a secondary molding material to the sole molding gap formed by the last, side mold, and bottom mold. In the method of manufacturing shoes having a two-layer sole formed by injection filling, a bottom mold protruding partition is provided in a part or a necessary part in the lateral direction at an appropriately arbitrary position on the surface of the bottom mold, and the protruding part is The partition part can be moved up and down by a vertical drive device embedded in the bottom mold, and the bottom mold is set at the primary molding gap position, and the protruding partition part is moved to the upper limit to bring it into close contact with the last, The void thus formed is injected and filled with a primary molding material to form a primary injection molded bottom, and then the bottom mold is lowered to the position of the secondary molding void and the protruding partition portion is moved to the lower limit, This is a method of manufacturing a shoe having a double-layered sole, in which the void thus formed is injected and filled with a secondary molding material to form a secondary injection-molded sole.

In this case, the primary molding material and the secondary molding material may be the same or different materials and/or materials of the same color or different colors, respectively. That is, these molding materials are compatible with each other when heated and melted, and can be used in any combination as long as they have adhesive properties.

Such a molding material is not particularly limited as long as it is a material commonly used for shoe soles, and for example, vinyl chloride polymer, thermoplastic rubber, polyurethane, etc. are used.

In addition, a foamable material can be used for both or one of the primary molding material and the secondary molding material. For example, when a foamable material is used for the primary molding material, the sole of the shoe Cushion properties can be improved, and if a foamable material is used as the secondary molding material, the weight of the shoe can be reduced. As such foamable molding materials, foamable vinyl chloride, foamable urethane, foamable rubber, etc. are used.

(Function) In the shoe manufacturing method according to the present invention, it is possible to form a two-layer sole, such as a midsole and an outsole, with one bottom mold without using any dummy bottom made by injection molding, which has been conventionally done. Moreover, the boundary lines in each layer can be ensured.

Further, the protruding partitions provided in the lateral direction on the surface of the bottom mold can be set at any appropriate position on the surface of the bottom mold. For example, when manufacturing shoes with good cushioning properties, the protruding partitions are It may be installed at the toe of the bottom mold to enlarge the injection filling gap for the primary molding material.

Furthermore, it is not necessary to provide the protruding partitions over the entire horizontal area of the bottom mold surface, but only on the side mold side, that is, on both sides of the bottom mold surface, in order to prevent the primary molding material from flowing into the toe area, for example. It is only necessary to provide it in some areas.

In addition, in order to reduce the weight of the two-layer shoe and to provide cushioning properties only at the heel, the protruding partition may be installed in the direction of the heel of the bottom mold.
Two-layer soles can be formed based on various designs.

Therefore, it is possible to manufacture shoes with a wide two-layer sole that is not dependent only on the shape of the dummy bottom, which was done in the conventional method.

In the present invention, a bottom mold protruding partition provided in a lateral part or a necessary part at an appropriately arbitrary position on the surface of the bottom mold is provided within the bottom mold (in this case, the bottom mold also includes the bottom plate). ) It can be moved up and down by a vertical drive device embedded in it. Such vertical drive devices include, for example, air cylinders, hydraulic cylinders, soleids, and the like. Therefore, at the stage when the bottom mold is set at the primary molding gap position, the protruding partition is positioned to the upper limit by the drive device, and as a result, the protruding partition is brought into close contact with the last, and injection molding is completed. This prevents material from leaking into other voids.

On the other hand, at the stage when the bottom mold is set at the second molding gap position, the protruding partition is moved to the lower limit by the drive device, so that after the injection molding of the protruding partition on the sole (non-injected part ), and the design becomes superior. The vertical movement for this purpose is about 3 to 6 mm on average.

Examples of the shoe coverings manufactured by the method of the present invention include woven fabrics, non-woven fabrics, knitted fabrics, leather, synthetic resin leather, etc. The shoe coverings to be attached to the last can be used in a normal last molding method. Both canifornia and string covers are applicable.
Therefore, shoes manufactured by the method of the present invention include athletic shoes, jogging shoes, and the like.

(Example) The present invention will be explained below based on the drawings.

1 to 4 show a method of manufacturing shoes according to the present invention. In Figure 1, the last 1
Insert 2 pieces into the bottom mold 3 respectively.
and a cross-sectional view from the last side when forming the primary molding gap 9 with the side mold 4.

That is, the shoe manufacturing method of the present invention uses a bottom mold 3 in which a bottom mold protruding partition 6 is provided in a part or a necessary part in the lateral direction at an appropriately arbitrary position on the surface 5 of the bottom mold 3. do. In this case, the protruding partition portion 6 is vertically movable by a vertical drive device 7 embedded within the bottom mold 3. In addition, 8 is a cavity in the bottom mold, and the protruding partition part 6 is a cavity in the bottom mold 3.
This is a hole through which a connecting member is passed so that it can move up and down in conjunction with each other on both sides.

In the shoe manufacturing method of the present invention, as a first step, as shown in FIG. is moved to the upper limit by the vertical drive device 7 and brought into close contact with the last 1. Then, the void 9 formed in this way
Then, the primary molding material is injected and filled through the injection port 10 to form the primary injection molded bottom.

The last cross-sectional view of FIG. 2 based on the - line in FIG. 1 is shown. That is, the protruding partition part 6 is moved to the upper limit by the drive device 7 and comes into close contact with the last 1, and the primary molding material injected and filled into the gap 9 is blocked by this protruding partition part, as shown in FIG. This prevents the fluid from flowing to the inner toe portion 11.

As shown in FIG. 5, in the conventional method, the last bottom 21 and the dummy bottom 15 having a specific shape are
This is because the midsole molding gap 16 formed by the above is not provided with any control means at its contact surface with the last 1 and the dummy bottom 15. This is intended to prevent the primary molding material from flowing into the toe portion 21 beyond this contact surface, which would inevitably make the boundary line of the midsole unclear, resulting in an undesirable design.

Next, after forming the primary molded bottom 12, as a second step, as shown in FIG. 3, the bottom mold 3 is set at a position to form the secondary molding gap 13,
The bottom mold projecting partition portion 6 is moved up to its lower limit by the vertical drive device 7. In this case, it is preferable to provide a step 6a as shown in FIG. 4 so that the part 6a of the protruding partition 6 is substantially flush with the surface 5 of the bottom mold 3 at the lower limit movable stage. And the void 1 formed in this way
3, the secondary molding material is injected and filled from the injection port 14 to form the secondary injection molded bottom.

FIG. 4 shows the last cross-sectional view based on the - line in FIG. 3.

In this second step, since the protruding partition portion 6 is moved to the lower limit by the vertical drive device 7,
The secondary molding material spreads smoothly into the voids 13, and the secondary injection molded sole is uniformly molded, making it possible to obtain the desired two-layer sole.

In addition, in FIGS. 1 to 4, the protruding partition portion 6 provided on the back surface 5 of the bottom mold 3 is located almost in front of the non-stepping part of the shoe, but this position is not suitable for the desired two-layer structure. It can be moved as appropriate to achieve this. Further, the installation portion thereof is not limited to both sides of the bottom mold, but can be installed at a desired position.

Further, in the above embodiment, the vertical movement drive device is embedded in the bottom mold, but it is also possible to embed them in the bottom plate that constitutes a part of the bottom mold.

(Effects) The method of the present invention uses the same last and bottom molds as described above, and furthermore, a bottom mold protruding partition is provided in the lateral direction at an appropriate arbitrary position on the surface of the bottom mold, and this is made vertically movable. A desired two-layer sole can be formed by this method, and it can be said that this method is particularly superior and simple compared to conventional manufacturing methods.

Furthermore, it is possible to prevent the molding material from flowing into the toe part, which was seen in the conventional method, and the product has an excellent appearance.

Furthermore, the shape of the double sole can be changed arbitrarily by selecting the installation position of the protruding partition, and weight reduction can also be achieved.

Furthermore, by appropriately combining the primary molding material and the secondary molding material, cushioning properties and weight reduction can be easily achieved.

[Brief explanation of drawings]

Figures 1 to 4 illustrate the manufacturing method of the present invention, of which Figure 2 shows -
4 is a cross-sectional view taken along the line -- in FIG. 3, and FIGS. 5A and B, and FIG. 6 illustrate the conventional manufacturing method. DESCRIPTION OF SYMBOLS 1...Last, 2...Flip cover, 3...Bottom mold, 4...Side mold, 6...Bottom mold protruding partition portion, 7...Vertical drive device, 9...Primary molding gap, 13 ...Second forming void.

Claims (1)

[Scope of Claims] 1. A shoe with a two-layer sole formed by sequentially injecting and filling a primary molding material and a secondary molding material into a sole molding cavity formed by a last, side mold, and bottom mold. In the manufacturing method, a bottom mold protruding partition is provided in a part or a necessary part in the lateral direction at an appropriately arbitrary position on the surface of the bottom mold, and the protruding partition is driven by a vertical drive device embedded in the bottom mold. The bottom mold can be moved up and down, and the bottom mold is set at the primary molding gap position, and the protruding partition is moved to the upper limit to bring it into close contact with the last, thereby filling the created gap with the primary molding material. Injection filling is performed to form a primary injection molded bottom, and then: the bottom mold is lowered to the position of the secondary molding gap, and the protruding partition is moved to the lower limit, and the secondary molding material is poured into the gap thus formed. A method for manufacturing a shoe having a two-layer sole, characterized in that the sole is injection-filled and a secondary injection-molded sole is formed. 2. The manufacturing method according to claim 1, wherein the primary molding material and the secondary molding material are materials of the same or different types and/or of the same color or different colors, respectively.