JPS6118441B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shoe sole in which a core material is embedded in a molding material and integrally molded, and a method for injection molding the sole.

Injection molded shoes use a core material in the sole, but conventionally, the core material is only buried in the sole and is not exposed on the outside except for special purposes. Nothing happened. As an example of showing the core material on the outer surface, for example, when showing two colors on the sole, as shown in FIG. Place the core material 3 on the mold surface of the bottom mold 5 of the female mold 4 so that there is a gap,
There is a method of molding a shoe sole by injecting a molding material having a different color from the core material 3 into the gap formed by the male mold 2 and the female mold 4. According to this method, one side of the core material 3 is entirely exposed on the bottom surface of the shoe, so naturally a wear-resistant material is used for the core material, but due to molding, the core material 3 is not wrapped in the injected molding material. Therefore, the peel strength is low, and the core material 3 may shift or move, or the injected molding material may enter between the core material 3 and the mold surface of the bottom mold 5, causing the core material 3 to rise.
The disadvantage is that it is difficult to obtain the desired product. Another method of expressing a part of the core material on the sole is as shown in FIG. A core material 16 having a flat surface in a space formed by a female die 15 consisting of
There is a method in which the shoe sole is molded by inserting the molding material into the shoe and then injecting the molding material from the injection port 17.

This method is effective as a method for obtaining shoes with two-color soles without using two-color indentation, but since the core material 16 appears in the recessed part of the sole,
The durability of the sole depends on the physical properties of the injection molded material that forms the convex part, and this method cannot be used for sneakers, tennis shoes, and other types of shoes that do not require large unevenness in the sole design. ,Moreover,
Since it is necessary to use a bottom mold with an uneven surface, there is a problem in that the production of the mold is expensive and the product is expensive.

The present invention uses a core material made of an elastic body having at least one convex portion on its surface, places this core material on the flat mold surface of a female mold, and presses it between the male and female molds to form a convex portion. The molding material is injected into the space in the mold in a compressed state, the convex part is embedded in the solidified layer of the molding material, and after the mold is released, the convex part is restored and the end face of the convex part is It is characterized by a projecting edge that protrudes further outward from the same plane as the lower surface of the solidified layer that forms the contact surface of the sole.

The case where the embodiment of the present invention is applied to injection molded shoes will be described below with reference to FIGS. 3 to 7. In FIG. 3, a space 26 of a mold is made up of a female mold 23 made up of a side mold 21 and a bottom mold 22, and a male mold 25 whose outer surface is covered with a spout 24.
Insert the core material 27 into. As shown in Fig. 4, the bottom mold 22 may have a step at the heel part and the treading part and a flat mold surface 22' at each part, or the heel part and the treading part may be made on the same plane. Use one with a molded surface. Also, core material 27
is made of an elastic body that is compatible with the injection molded material and has greater physical strength and excellent abrasion resistance than the injection molded material, and is processed into the shape of a shoe sole, and has convex portions 28 on its surface. are provided in one piece.

The convex portion 28 is provided at at least one location and has an area that can hold the core material 7 in a certain shape.For example, as shown in FIG. In addition to providing convex portions 28, 28, .
Only for areas of the heel that are subject to particularly high wear.
It is also possible to provide a convex portion 28 having an appropriately set size and shape such as a circular shape, an oval shape, a crescent shape, or the like.
This convex portion 28 is placed on the flat mold surface 22' of the bottom mold 22 and pressed between the male and female molds 23 and 25,
With the convex portion 28 compressed by a certain amount, the molding material is injected into the closed mold through the injection port 29 opened in the side mold 21. The injected material penetrates into the spaces formed around the core material 27 and between the convex portions 28, 28, . The convex portion 28 is embedded in the solidified layer 30 . Next, when the molded product is released from the mold, the convex portions 28 that were restricted between the male and female molds try to recover with their own elasticity, but because they are fixed to the solidified layer 30; The end surface of the convex portion 28 exposed from the lower surface of the solidified layer 30 expands and protrudes downward, resulting in an injection molded shoe 31 having a convex edge on the ground contact surface of the sole as shown in FIG.

In the above embodiment, the sole of the injection molded shoe has been described, but instead of the male mold 25 covered with the cover 24, a male mold that only covers the upper surface of the female mold 23 is used, and the sole is similarly molded into the mold. It is also possible to mold soles for slouch shoes by injecting the material.

As described above, according to the present invention, by selecting an elastic body for the core material 27 and using a mold having a flat mold surface, it is possible to obtain a shoe sole having unevenness on the ground contact surface. Since variations in the pattern are not restricted by the mold, soles with various uneven shapes can be molded using one type of mold. The end surface of the convex portion that protrudes from the ground surface of the sole formed by the method of the present invention as a protrusion becomes anti-slip,
Furthermore, by using a material with excellent abrasion resistance and strength for the core material 27, shoes with excellent abrasion resistance can be obtained.Moreover, since the entire core material is embedded in the molding material, The core material lifts up,
It will not peel off. Of course, according to the method of the present invention, the convex portion 2 of the core material 27 can be removed by one injection operation.
8 can appear as a protruding edge on the surface of the solidified layer 30 of the injection molded material, so by using different colors for the core material and the injection molded material, it is possible to create an appearance similar to that of a two-color injection bottom. It is possible to obtain soles that exhibit the same characteristics. Further, according to the present invention, it is possible to use a bottom mold in which the mold surfaces of the stepping part and the heel part are flat, but it is of course possible to use a bottom mold in which a textured pattern or other unevenness is formed on the mold surface. Needless to say.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views of a mold for explaining a conventional shoe sole molding method, FIG. 3 is a cross-sectional view of an embodiment of a shoe sole molding mold for carrying out the method of the present invention, and FIG. 4 is a bottom FIG. 5 is a perspective view of a mold, FIGS. 5 and 6 are perspective views showing embodiments of the core material, and FIG. 7 is a partially sectional perspective view of an injection molded shoe equipped with the sole of the present invention. 21... Side mold, 22... Bottom mold, 23... Female mold, 25... Male mold, 27... Core material, 28... Convex portion, 30... Solidified layer, 31... Injection molded shoe.

Claims (1)

[Claims] 1. A core material made of an elastic body with at least one convex portion protruding from the surface, and a solidified layer of an injection molding material that is laminated to the core material and has the convex portion embedded therein. It is characterized by having a protruding edge whose end surface protrudes outward from the lower surface of the solidified layer, which becomes the contact surface of the sole by utilizing the expansion and restoring force of the convex portion of the core material buried in the layer in a compressed state. The sole of the shoe. 2. A core material made of an elastic body having at least one convex portion on its surface is housed in a mold that is a combination of a male mold and a female mold, and the convex portion of the core material is placed on the flat mold surface of the female mold. The molding material is placed on top and squeezed within the male and female molds, and the molding material is injected into the space within the molding mold with the convex portions compressed, the convex portions are embedded in the solidified layer of the molding material, and after the mold is released,
It is characterized by restoring the convex part and expanding it so that the end face of the convex part protrudes further outward as a ridge from the same plane as the lower surface of the solidified layer forming the contact surface of the sole, thereby forming an uneven shape on the contact sole. Injection molding method for shoe soles.