JPH0691844B2 - Injection molding of shoes with multicolor soles - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding method for shoes having a multicolor sole.

[0002]

2. Description of the Related Art In recent years, shoes having multicolored soles have been favored. In the method of forming these shoes, first, a grounding sole is formed by using a dami last and a bottom mold, and then a dami A method was used in which a bottom mold, in which the last was removed and the grounding bottom was formed and held, was set with the last in which a side mold and a cover were hung, and a midsole was multi-layered on the upper surface of the grounding bottom.

However, according to this method, when the damalast is removed from the bottom mold after the ground bottom is molded, the ground bottom floats up from the molding surface of the bottom mold.
When molding a midsole, the midsole molding material penetrates into the side surface or the bottom surface of the grounding bottom floating from the molding surface of the bottom mold, and the boundary between the grounding bottom and the midsole is unclear and complicatedly entered. And the appearance of the shoe sole was significantly deteriorated.

Therefore, as shown in Japanese Examined Patent Publication No. 61-28327, when forming a ground bottom, after forming a burr on the outer peripheral upper edge portion integrally with the ground bottom in the horizontal direction, the mid sole is molded. At the lower edge of the outer circumference of the shoe, burrs were horizontally formed integrally with the midsole, and after molding the shoe sole, burrs integral with the grounding sole and burrs integral with the midsole were cut and removed with a knife.

However, it is difficult to remove the burr,
In addition, there is a defect that the appearance is significantly deteriorated because the burr cutting marks are left on the side surface of the shoe sole.

[0006]

SUMMARY OF THE INVENTION The present invention seeks to provide, by a simple method, a shoe having a multicolor sole having a good appearance with a clear boundary between a ground sole and a midsole and easy removal of burrs. It is a thing.

[0007]

The present invention will now be described with reference to the drawings showing the embodiments thereof.
Using the last 1 and the bottom mold 2, the ground bottom molding material is injected into the ground bottom molding cavity 01 to mold the ground bottom g, and at the same time, through the inflow hole 25 narrowed toward the ground bottom molding cavity 01. Then, the grounding bottom molding material is made to flow into the protrusion groove 22 formed in the upper surface 211 of the flange portion of the bottom mold, and the burr a is formed integrally with the grounding bottom g through the slag b molded by the inflow hole 25. After doing, dami
The last 1 is replaced by a side mold 3.3 that can be opened and closed and a last 4 in which the cover u is suspended, and a midsole molding cavity 02 is formed on the upper surface of the grounding bottom g.
In the mold forming cavity 02, the runner 32.32 opened on the lower surface of the side mold 3.3 so as to face the protruding groove 22.22 of the bottom mold and the molding side face 31.31 of the side mold are narrowed. The midsole molding material is injected through the gate 33.33 to mold the midsole m, the ground bottom g and the cover u are integrated through the midsole m, and the runner 32. The subject matter of the invention is an injection molding method for a shoe with a multicolor sole, characterized in that runner slugs c, c formed in 32 are integrated with burrs a, a.

As shown in FIG. 1, the bottom mold 2 is provided with a grounded bottom molding concave portion 20, the bottom surface of which is provided with an uneven design 201.201 ... Is formed with a flange portion 21, and this flange portion 21 is designed to form a fitting portion with the side mold 3.3 at the time of molding the midsole. The flange portion 21 is formed with a protrusion groove 22 which is opened in the upper surface 211 thereof.

The protruding groove 22 may be formed in an arbitrary shape, but if it is formed in a sectional shape enlarged toward the upper surface thereof, the upper surface 21 of the flange portion 21 after the shoe sole is formed.
The burr a formed in the protruding groove 22 can be easily removed from the first side, which is convenient. The protruding groove 22 may be provided around the flange portion 21 in a series, or a plurality of grooves 22.22 '... may be provided independently at certain intervals. Further, in the present invention, an inflow hole 25 is provided so as to communicate 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 formed in a groove shape by opening on the upper surface 211 of the flange portion. And this inflow hole 2
An appropriate number of 5.25 are provided toward the protruding groove 22. The inflow hole 25 is formed in the ground bottom molding cavity 01.
Is narrowed toward. The inflow hole 25 forms a slag portion b narrowed toward the ground contact bottom side surface g.

The side mold 3.3 is provided with an injection runner 32.32 along the molding side surface 31.31 around the outer circumference of the heel part to the stepped part. Then, from this runner 32.32, the side surface molding side 3
An injection gate 33.33 narrowed toward 1.31 or the mid-sole molding cavity 02 is formed. The gate slug e.n. narrowed toward the midsole m by the injection gate 33.33. e is formed. The injection gate 33.33 may be provided in a tunnel shape in the side mold, or may be provided in a groove shape opened on the lower surface of the side mold.

In injection molding of a shoe having a multicolor sole according to the present invention, the bottom mold 2 and the dami last 1 are fitted to each other, and the bottom mold 2 and the dami last 1 are partitioned and formed. When the grounded bottom molding material is injected into the grounded bottom molding cavity 01, a part of the grounded bottom molding material is filled in the protrusion groove 22 through the inflow hole 25, and the inflow hole 2
A slug b and a burr which are narrowed together with the ground contact bottom are formed by the groove 5 and the protruding groove 22, and the ground contact bottom g is held in the bottom mold and the cavity 23 by the slug b and the burr a. Therefore, when the dummy last 1 is removed from the bottom mold 2, the grounded bottom g is not lifted or separated from the bottom mold cavity 23. In this way, a bottom model having the grounded bottom g formed and held
Ludo 2 is the last 4 with side mold 3 and cover u
And forming a midsole molding cavity 02 on the upper surface of the grounding bottom, and injecting a midsole molding material into this midsole molding cavity through an injection runner 32.32 and an injection gate 33.33. , The midsole m is molded, the ground bottom g and the covering u are integrated through the midsole m, and the runners 32.
Runner-slug c. Formed by 32. c. Integrate c. In this way, a multicolor shoe sole gm in which the ground contact sole g and the mid sole m are integrated is formed.

After molding the multicolor shoe sole gm in this manner, the mold is opened by a conventional method, that is, the bottom mold 2
To release the side mold 3.3 and remove the shoe with the multicolor sole gm from the last 4.
When the bottom mold 2 is lowered, the ground contact bottom g is integrated with the covering u suspended from the last 4 through the mid sole m, so that the ground contact bottom g is narrowed on its side surface. Of the bottom mold 2 and is released from the bottom mold 2. Further, since the burr a portion is integrated with the runner-slag c, it is pulled out together with the slag b from the protruding groove 22. And side mold 3.3
, The midsole m is narrowed at its sides by the end e '. Of the gate slug. It is torn off from e'and released from Side Mold 3.3. After opening the mold in this manner, the shoe having the multicolor sole gm formed according to the present invention is released from the last 4.
Then, in preparation for the next molding of the multicolor sole, the runner-slug c,
If c is removed from the runner 32.32, the gate slag e, the burr a, and the slag b integrated with the runner 32.32 can be removed at the same time.

[0013]

Since the present invention is constructed as described above, when the ground bottom is injection-molded by using the dummy last 1 and the bottom mold 2, the inflow hole 25 and the protruding groove 22 are provided.
In addition, since the ground bottom g is held in the bottom mold cavity 23 by the slug b and the burr a which are integrally formed with the ground bottom g, when the dami last 1 is replaced with the side mold 3 and the last 4, The ground bottom g is the ground bottom molding recess 2
0 is not peeled from the bottom mold cavity 23 or lifted from the bottom mold cavity 23, and the ground bottom g is kept in close contact with the molding surface of the ground bottom molding recess 20 and the midsole molding cavity is formed on the ground bottom g upper surface. 02,
A midsole molding material can be injected into the midsole molding cavity 02 to mold the midsole m. Therefore, the molded sole molding material does not stick out to the side surface of the ground contact bottom g during molding of the molded sole, and the multi-colored sole g has a good appearance.
m is obtained. The burr a formed integrally with the ground bottom g at the time of molding the ground bottom g is formed integrally with the midsole m at the time of molding the midsole m from the end b'of the slag narrowed on the side surface of the ground bottom. The runner slug c is an end e ′ of the gate slug narrowed on the side of the mid sole.
Since each of them is torn off at the time of opening the mold, no burr cutting work is required as in the conventional case, and the appearance of the multicolor shoe bottom gm is not deteriorated by the burr cutting marks. Moreover, since the runner slug c, the gate slug e, the burr a, and the slag b can be removed at the same time after molding the multicolor shoe sole, the burr a can be easily removed.

[Brief description of drawings]

FIG. 1A is a cross-sectional view of essential parts showing a grounded bottom molding state. FIG. 3B is a cross-sectional view of essential parts showing a molded state of the midsole.

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

FIG. 3 is a cross-sectional view of essential parts showing an opened state of the mold after molding of a multicolor shoe sole.

[Explanation of symbols]

 01. Grounded bottom molding cavity 02. Mid-sole molding cavity 1. Dummy last 2. Bottom mold 20 ... Recess 201 ... Uneven design 21 ... Flange part 211 ... Upper surface 22, 22 '... Projection groove 25 ... Inflow hole 3. Side mold 31 ... Molding side surface 32. Runner-33. Gate 4. Last a. Bali b. Slug b '... end c. Runner-slag e. Gate slug e '... end g. Ground floor m. Midsole gm. Multicolored soles u. Cover

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B29L 31:50 4F

Claims (1)

[Claims] 1. A dummy bottom 1 and a bottom mold 2 are used to inject a grounded bottom molding material into a grounded bottom molding cavity 01 to mold a grounded bottom g, and constriction toward the grounded bottom molding cavity 01. The grounded bottom molding material is flown into the protrusion groove 22 formed in the upper surface 211 of the flange portion of the bottom mold through the inflow hole 25, and the grounded bottom g is passed through the slag b formed by the inflow hole 25. Together with Bali a
After molding, the dami last 1 can be opened and closed freely
Replaced with the ground 3.3 and the last 4 in which the cover u is suspended, a mid-sole molding cavity 02 is formed on the upper surface of the grounding bottom g, and on the bottom of the side mold 3.3 on this mid-sold molding cavity 02. Bottom mold protruding groove 2
The midsole molding material is injected by injecting the midsole molding material through the runner 32.32 opened opposite to 2.22 and the gate 33.33 narrowed toward the molding side surface 31.31 of the side mold. m is molded to integrate the ground bottom g and the covering u through the midsole m, and the runner
32. An injection molding method for shoes having a multicolor sole, wherein the runner-slugs c, c formed in 32.32 are integrated with burrs a, a.