JPH04221501A - Injection molding method of shoe having multiplecolored sole - Google Patents

Abstract

PURPOSE:To obtain a shoe with a multiple-colored sole excellent in appearance and easy to remove a burr. CONSTITUTION:A burr (a) is integrally molded with a grounding sole (g) via a slug (b) by using a dummy last 1 and a bottom mold 2. The dummy last 1 is replaced with side molds 3, 3 of free opening/closing and a last 4 provided with an upper skin (u). A mid-sole (m) is integrally molded on an upper surface of the grounding sole (g) and a runner slug (c) is on an upper surface of the burr (a), respectively. The bottom mold 2 is lowered to open the side molds 3, 3 and the burr (a) as well as the runner slug (c) is torn off from a multiple- colored sole gm. The burr (a) is removed together with the runner slug (c).

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for injection molding shoes with multicolored soles.

0002

[Prior Art] In recent years, shoes with multi-colored soles have become popular.In the molding method for these shoes, first, a dummy last and a bottom mold are used to mold the ground sole, and then a dummy last and a bottom mold are used to form the ground sole. A method was adopted in which the last was removed and the bottom mold was molded and held, and the last with the side molds and sleeves suspended was set, and the midsole was layered and molded on top of the bottom.

However, when this method is used, when the dummy last is removed from the bottom mold after the ground-contact sole is molded, the ground-contact sole rises from the molding surface of the bottom mold, and when the midsole is molded, the midsole molding material This invades the side or lower surface of the ground sole that has risen from the molding surface of the bottom mold, and the boundary between the ground sole and the midsole becomes unclear and intricate, significantly deteriorating the appearance of the sole.

Therefore, as shown in Japanese Patent Publication No. 61-28327, after molding a burr horizontally on the upper edge of the outer periphery of the ground-contact sole, when molding the midsole, A burr is formed horizontally on the lower edge of the outer periphery of the shoe, integrally with the midsole, and after the sole is molded, the burr that is integral with the ground sole and the burr that is integral with the midsole are removed by cutting with a knife.

However, it is difficult to cut and remove the burr.
Moreover, the burr cut marks remain on the side of the sole, resulting in a significant deterioration in appearance.

[0006]

[Problems to be Solved by the Invention] The present invention aims to provide, by a simple method, a shoe with a multicolored sole that has a clear boundary between the ground sole and the midsole, has a good appearance, and is easy to remove burrs. It is something.

[0007]

[Means for Solving the Problems] This invention will be explained below with reference to drawings showing its implementation state.
Using the last 1 and the bottom mold 2, the ground bottom molding material is injected into the ground bottom molding cavity 01 to form the ground bottom g, and the material is injected into the ground bottom molding cavity 01 through the inflow hole 25 narrowed toward the ground bottom molding cavity 01. Then, the grounding bottom molding material is flowed into the protruding groove 22 opened on the upper surface 211 of the flange part of the bottom mold, and the slag b formed by the inflow hole 25 is
After molding the barrier integrally with the grounding sole g through the
A midsole molding cavity 02 is formed on the upper surface of the ground sole g, and a bottom mold protruding groove 22. is formed on the lower surface of the side mold 3.3 in this midsole molding cavity 02. 22 and a gate 33.33 narrowed toward the molding side surface 31.31 of the side mold.
Inject the midsole molding material through the midsole m
is molded, and the ground sole g and the lace cover u are formed through the midsole m.
Invented an injection molding method for shoes with multicolored soles characterized by integrating the runner slugs c and c formed in the runners 32 and 32 with the barriers and a. This is the gist of the report.

As shown in FIG. 1, a ground-contact bottom molding recess 20 is formed in the bottom mold 2, and an uneven design 201, 201, . A flange portion 21 is formed, and this flange portion 21 is formed in the side mold 3. when the midsole is molded.
It is designed to form a fitting part with 3. The flange portion 21 has a protruding groove 2 opened on its upper surface 211.
2 is formed.

This protruding groove 22 may be formed in any shape, but if it is formed in a cross-sectional shape that is enlarged toward the upper surface, the flange portion upper surface 21 can be formed after the sole is formed.
This is convenient because the barrier formed in the protruding groove 22 can be easily removed from the first side. This protruding groove 22 may be provided around the flange portion 21 in a continuous manner, or a plurality of grooves 22, 22' may be provided partially independently at regular intervals. In the present invention, an inflow hole 25 is provided in communication with the side surface of the molding recess 20 of the bottom mold from the protruding groove 22. This inflow hole 2
5 may be provided in the flange portion in a tunnel shape as shown in FIG. 1, or may be opened in the flange portion upper surface 211 and formed in a groove shape. And this inflow hole 25
．． 25 are provided in an appropriate number toward the protruding groove 22. This inflow hole 25 is narrowed toward the grounded bottom molding cavity 01. This inflow hole 25 forms a slug portion b that is narrowed toward the grounded bottom side surface g.

[0010] The side mold 3.3 is provided with injection runners 32.32 along its molded side surface 31.31 and around its outer periphery from the heel portion to the tread portion. From this runner 32.32, the molding side 3 of the side mold
1.31, that is, an injection gate 33.33 is formed which is narrowed toward the midsole molding cavity 02. The gate slug e. is narrowed toward the midsole m by the injection gates 33 and 33. e is formed. The injection gates 33.33 may be provided in the form of a tunnel in the side mold, or may be provided in the form of a groove opened in the lower surface of the side mold.

In injection molding of shoes with multicolored soles according to the present invention, the bottom mold 2 and the dummy last 1 are fitted together, and the bottom mold 2 and the dummy last 1 are formed into sections. When the ground bottom molding material is injected and introduced into the ground bottom molding cavity 01, a part of the ground bottom molding material passes through the inflow hole 25 and fills the protruding groove 22, and the inflow hole 2
5 and the protruding groove 22, a slug b and a barrier a are formed integrally with the ground bottom, and the ground bottom g is held in the bottom mold and the cavity 23 by the slug b and the barrier. Therefore, when the dummy last 1 is removed from the bottom mold 2, the grounded bottom g is not lifted up from the bottom mold cavity 23 or peeled off. The bottom mold 2 with the grounding sole g molded and held in this way is assembled with the side mold 3 and the last 4 covered with the sleeve U, and a midsole molding cavity 02 is formed on the upper surface of the grounding sole. - Inject the midsole molding material into the molding cavity of the midsole through the injection runner 32.32 and the injection gate 33.33 to mold the midsole m, and connect it to the ground sole g through the midsole m. In addition to integrating the cover u, a runner 32.3 is placed on the top surface of the barrier a.
Runner slug formed by 2 c. Integrate c. In this way, a multicolored shoe sole gm is formed in which the grounding sole g and the midsole m are integrated.

After molding the multicolored shoe sole gm in this manner, the mold is opened in a conventional manner, that is, the bottom mold 2 is lowered and the side molds 3.3 are opened to form the multicolored shoe sole gm.
A shoe with m is removed from the last 4, but when lowering the bottom mold 2, the grounding sole g is removed from the midsole.
Since it is integrated with the slug cover U suspended from the last 4 through the mold 2, the grounding bottom g is torn off from the end b' of the slug narrowed on its side surface, and is separated from the bottom mold 2. Released from the mold. And the barrier part is the runner slug c
Since the slag b is integrated into the protruding groove 22,
It will be pulled out along with it. Then, when the side mold 3.3 is opened, the midsole m is located at the narrowed end e' of the gate slug on its side surface. Torn to pieces from e',
The mold is released from the side mold 3.3. After opening the mold in this manner, the shoe having the multicolored sole gm molded according to the present invention is removed from the last 4. Runner slug c, ready for molding the next multi-colored shoe sole.
If c is removed from the runners 32 and 32, the gate slug e, barrier, and slug b integrated therein can be removed at the same time.

[0013]

[Effects of the Invention] Since the present invention is constructed as described above, when injection molding the ground bottom using the dummy last 1 and the bottom mold 2, the ground bottom is inserted into the inflow hole 25 and the protruding groove 22. Since the grounding bottom g is held in the bottom mold cavity 23 by the slug b and barrier formed integrally with g, when replacing the dummy last 1 with the side mold 3 and the last 4, the grounding bottom g is Ground bottom molding recess 20
The midsole molding cavity 02 is formed on the upper surface of the grounding sole g while keeping the grounding sole g in close contact with the molding surface of the bottom molding recess 20 without peeling or lifting from the bottom mold cavity 23 from the molding surface of the grounding sole g. A midsole m can be molded by injecting a midsole molding material into this midsole molding cavity 02. Therefore,
The midsole molding material does not protrude to the side surface of the ground sole g during midsole molding, and a multicolored shoe sole gm with a good appearance can be obtained. In addition, a barrier a, which is formed integrally with the grounding sole g when the grounding sole g is formed, is formed integrally with the midsole m when the midsole m is formed, from the narrowed end b' of the slug on the side surface of the grounding sole. Runner slug c is midsole
Since the gate slugs are torn to pieces at the time of opening the mold from the narrowed end e' of the gate slug on the side of the mold, there is no need to cut burrs as in the conventional method, and the burr cut marks can be used to create multi-colored shoe soles. The appearance of the product is not degraded. Furthermore, after molding the multi-colored shoe sole, runner slug c, gate slug e, barrier, and slag b can be removed at the same time.
is easy to remove.

[Brief explanation of the drawing]

FIG. 1 (A) is a sectional view of a main part showing a formed state of a grounding sole. (B) is a sectional view of a main part showing a molded state of the midsole.

FIG. 2 is a plan view showing a molded state of the midsole.

FIG. 3 is a cross-sectional view of a main part showing the open state of the mold after molding the multicolor shoe sole.

[Explanation of symbols]

01. Ground bottom molding cavity 02. Midsole molding cavity 1. Dummy last 2. bottom motor
lead 20... recess 20
1... Uneven design 21... Flange part 2
11...Top surface 22, 22'...Protruding groove

Claims (1)

[Claims] Claim 1: Using a dummy last 1 and a bottom mold 2, a ground bottom molding material is injected into a ground bottom molding cavity 01 to form a ground bottom g, and the material is narrowed toward the ground bottom molding cavity 01. The grounding bottom molding material is made to flow into the protruding groove 22 opened on the upper surface 211 of the flange portion of the bottom mold through the inflow hole 25, and the grounding bottom g is formed through the slug b formed by the inflow hole 25. After molding the barrier integrally with the dummy last 1, the dummy last 1 is replaced with a side mold 3.3 that can be opened and closed, and the last 4 into which the sleeve U is hung, and a midsole molding cavity 02 is formed on the upper surface of the ground bottom g.
In this midsole molding cavity 02, a runner 32.32 opened on the lower surface of the side mold 3.3 opposite to the protruding groove 22.22 of the bottom mold, and a molded side surface 31 of the side mold are formed. The midsole molding material is injected through the gate 33 and 33 narrowed toward .31 to form the midsole m, and the ground sole g and the cover U are integrated through the midsole m. Injection molding method for shoes with multicolored soles, characterized in that the runner slugs c, c formed in the runners 32.32 are integrated with the barriers a, a.