JPS5926281B2 - shoe manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a shoe having a two-layer sole made of polyurethane foam and an elastic material such as rubber.

Foamed polyurethane has traditionally been recognized for its lightweight and highly abrasion-resistant properties, and has been widely used in shoe soles. However, in recent years, foamed polyurethane has been found to be inferior in cold resistance and slip resistance, so elastic materials such as rubber have been used. Aiming for a synergistic effect between the lightweight and easily moldable properties of foamed polyurethane and the excellent abrasion resistance and anti-slip properties of rubber and other elastic materials, the two-layer structure of foamed polyurethane and rubber and other elastic materials was reconsidered. Shoes with soles are manufactured.

However, the manufacturing method for these shoes involves injecting or injecting polyurethane into the space corresponding to the mid-sole formed by the shoe cover attached to the last, the lateral mold, and the bottom mold, causing a foaming and hardening reaction. After attaching the midsole to the cover, the pre-formed tread sole is manually glued to the tread side of the midsole, and the worker attaches the protruding piece that comes out when forming the midsole and the pre-formed contact sole. This requires the laborious and inefficient manual work of manually removing each protruding piece of the bottom of the ground, and then correctly positioning the grounding sole on the grounding surface side of the midsole and adhering it with adhesive. It has been lost.

Further, as shown in FIG. 2, the ground sole 1 from which protruding pieces have been removed in advance is placed on the bottom mold 3, and a space corresponding to the midsole 9 portion is formed by the horizontal mold 6 and the cover 8 attached to the last 7. In the method of injecting or injecting polyurethane to cause a foaming and curing reaction, and integrally molding the midsole 9 and the grounding sole 1 made of foamed polyurethane on the cover 8, the circumferential surface of the grounding sole 1 and the inner surface of the horizontal mold 6 are Even if it is assumed that there is no gap, since the grounding sole 1 is an elastic body, the grounding sole 1 will be distorted by the foaming pressure after injection or injection of polyurethane.
The protruding pieces of foamed polyurethane adhered to the circumferential surface of the grounding sole 1 in an irregular pattern, making it impossible to clearly distinguish the boundary line between the two layers of foamed polyurethane and the grounding sole, as shown in Fig. 3. Midsole 9 made of foamed polyurethane
Shoes are manufactured in which the outer peripheral part of the ground-contacting sole 1 is covered with the same color as the midsole 9 when viewed from the side.

However, the present invention has a two-layer sole made of foamed polyurethane and an elastic material such as rubber, and the foamed polyurethane midsole layer and the grounded sole layer made of an elastic material such as rubber do not mix and are clearly distinguished as layers on the outer peripheral side of the grounded sole. This invention is a method for manufacturing shoes having a two-layer sole made of separable foamed polyurethane and an elastic material such as rubber.

Examples will be described below with reference to the drawings.

As shown in Figure 1, the grounding sole 1 is molded in advance, and is made of an elastic material such as rubber or thermoplastic resin, and is surrounded by an appropriate width around the periphery of the opposite side of the grounding surface. A thin sheet-like partition piece 2 is formed.

The grounding sole 1 is housed in a concave portion 4 formed to have the same size as the grounding sole 1 of the bottom mold 3, and the partition piece 2 is arranged between the bottom peripheral surface 5 of the bottom mold 3 and the bottom peripheral surface of the horizontal mold 6. 11.

A space 12 is formed by the grounding sole 1 housed in the sole mold 3, the collar 8 attached to the last 7, and the horizontal mold 6 having a vertical surface 10 corresponding to the side peripheral surface of the midsole 9.

The space 12 is shaped to correspond to the midsole 9.

Liquid polyurethane is injected into the space 12 from the injection hole 13 to cause a foaming and curing reaction, and at the same time as the midsole 9 is formed, it is integrally molded in close contact with the shoe cover 8 and the ground sole 1, and after demolding, appropriate work is carried out. By removing the partition piece, a shoe having a desired two-layer sole made of polyurethane foam and an elastic material such as rubber can be obtained.

The above has described the manufacturing method by injection molding, but it goes without saying that the grounding sole 1 is housed in the sole mold 3, and liquid polyurethane is injected into the space 12 corresponding to the midsole 9 formed by clamping the horizontal mold 6. Immediately, the last 7 with the lace cover 8 attached thereto is attached, and the foaming and hardening reaction occurs within the space 12, so that the lace cover 8 and the ground sole 1 can be molded in close contact with the sole 1 at the same time as the midsole 9 is formed. Cast molding can also be used in the same manner as injection molding.

When molding the ground sole 1, in order to make the bottom design clearly appear, the bottom material is overcharged in the recessed part of the mold, and during mold firing, the excess bottom material is used to dispose of the excess bottom material on the outer periphery of the surface opposite to the ground surface. It is extruded as a protruding piece, and the same effect can be obtained even if this protruding piece is used without being removed.

The present invention provides a partition piece 2 of a grounding bottom 1 which is formed in advance as described above.
is sandwiched between the bottom peripheral surface 5 of the bottom mold 3 and the bottom peripheral surface 11 of the horizontal mold 6, and is placed in the space 12 formed by the grounding bottom 1, the horizontal mold 6, and the cover 8 attached to the last 7. Since it is filled with liquid polyurethane, foamed and cured, and at the same time is integrally molded in close contact with the cover 8 and the grounding sole 1, the bottom circumferential surface 5 and the bottom circumferential surface 11 that sandwich the partition piece 2 are tightened. Even if the bottom circumferential surface 11 is slightly scratched or foreign matter is trapped, the liquid polyurethane will not leak out from between the partition piece 2 and the bottom circumferential surface 11 due to the filling pressure and foaming pressure. Partition piece 2 is minute and has a long and wide area.
This ensures that the outflow can be stopped, and the foamed polyurethane crosses the partition piece 2 of the grounding sole 1.
Since it does not flow out to the circumferential side of the ground sole 1 and the circumferential side of the midsole 9, there is no mixing at the boundary between the circumferential side of the ground sole 1 and the circumferential side of the midsole 9. By simply removing the partition piece, it is possible to provide a shoe having a two-layer sole made of foamed polyurethane and an elastic material such as rubber, which can be clearly distinguished and colored as layers.

In addition, the manufacturing process is simple and easy, which improves productivity and simplifies work, and provides shoes with a clear and elegant double-layered sole.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway sectional view showing an embodiment of the present invention;
FIG. 2 is a partially cutaway sectional view showing a conventional example, and FIG. 3 is a sectional view of a conventional shoe. 1... Ground bottom, 2... Partition piece, 3.
...Bottom mold, 4...Concave part, 5...
・Bottom peripheral surface, 6...Horizontal, 7...Last, 8...Flip cover, 9...Mitsudosole, 10...Vertical Surface, 11...Bottom peripheral surface, 12...Space, 13...Injection L

Claims (1)

[Scope of Claims] 1. A space corresponding to the bottom is formed by assembling the last coated with the cover, a horizontal mold, and a bottom mold, and the space is appropriately filled with bottom material by cast molding or injection molding. In the method of manufacturing shoes in which the sole is integrally molded on the heel, the ground sole 1 is made of an elastic material such as rubber and has a thin sheet-like partition piece 2 integrally formed on the periphery of the opposite side of the tread surface and appropriately surrounds the periphery. is prepared in advance, the recessed part 4 of the bottom mold 3 is formed to have the same size as the grounding bottom 1, the grounding bottom 1 is stored in the recessed part 4, and the partition piece 2 of the grounding bottom 1 is inserted into the bottom mold. 3 bottom peripheral surface 5
and the bottom peripheral surface 11 of the horizontal mold 6.
The space 12 formed by the grounding sole 1 and the horizontal die 6 is filled with liquid polyurethane, foaming and hardening is performed, and the molding is closely adhered to and integrally formed with the cover 8 and the grounding sole 1, and the replacement section 2 is removed from the mold. A method of manufacturing shoes characterized by: