JPH0543361B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing injection molded shoes using a dummy mold and double stamping.

Traditionally, the double-injection method of manufacturing injection molded shoes using dummy molds has been used despite a number of drawbacks.

That is, after injecting the primary outsole material into a primary cavity composed of a dummy mold, a horizontal mold, and a bottom mold to form the primary outsole, the dummy mold is removed and the last molded material is fitted with a cover. After injecting the secondary sole material into the secondary cavity composed of the horizontal mold and the bottom mold on which the primary sole is placed, to form the secondary sole, the horizontal mold and the bottom mold are used to form the last. In this case, injection molded shoes were obtained by taking off the shoes.
After forming the primary outsole, when removing the dummy mold, at least a part of the primary outsole adheres to the bottom surface of the dummy mold, and as a result, the primary outsole rises from the bottom design surface of the bottom mold. It often becomes shaky,
If injection molding of the secondary sole material is performed in this state, the secondary sole material will be injected between the primary outsole and the bottom design surface of the bottom mold, and will not be formed into the desired laminated state. This led to the manufacture of injection molded shoes with defective soles.

Therefore, if the primary outsole rises from the bottom design surface of the bottom mold as described above, the worker must push it back into its original position by hand or use another device to push it back. It's tedious, inefficient, and dangerous.

In order to eliminate these drawbacks, Japanese Patent Publication No. 59-43162 entitled "Method for Manufacturing Injection Molded Shoes" discloses a bottom mold in which a part of the bottom mold design or a front overhang design is provided on the upper surface of the bottom mold. However, in the above invention, the sole design provided on the upper surface of the bottom mold is partially or entirely limited to an overhang sole design. This has the drawback that the scope of application is narrow because it cannot be used for anything other than an overhang bottom design.Also, the bottom design is an overhang design, that is, it is formed in an undercut shape, so the base of the design is Since it is finer than the tip, the strength of the bottom design is weakened, and furthermore, it has the disadvantage that it shakes and becomes unstable when it touches the ground.

However, the present invention provides a method for manufacturing injection molded shoes that overcomes the above-mentioned conventional drawbacks and also exhibits a cushioning effect.

The present invention provides a method for manufacturing injection molded shoes in which a dummy mold is used to stamp twice to obtain a primary sole and a secondary outsole, which are formed as a partial sole or a full sole. A method for manufacturing an injection molded shoe, characterized by using a sole mold having a horizontal or diagonal through hole or hole in the side surface of a protrusion protruding from a part or a necessary part of the shoe, and further a sole mold. The present invention relates to a method of manufacturing injection molded shoes, characterized by using a sole mold having a hole that widens toward the bottom on the upper surface thereof.

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows that a primary outsole material is injected from a first injection hole 4 into a primary cavity 5' formed by a dummy mold 1, horizontal molds 2, 2, and bottom mold 3, and a primary outsole 5 is formed. Indicates the state in which

Figure 4 shows that during the molding process, when the dummy mold 1 is removed, the right part of the primary outsole 5 is attached to the lower surface of the dummy mold 1, and the horizontal molds 2, 2 and the cover 6 are left in a turned-up state. A secondary cavity 8' is shown formed by the fitted last 7.

FIG. 2 shows a state in which the primary outsole 5 is normally fixed to the sole mold 3 in FIG. 4.

Figure 3 shows the secondary cavity 8' in Figure 2.
shows a state in which the secondary sole material is injected from the second injection hole 9 and the secondary outsole 8 is formed.

FIG. 5 shows a protrusion 10 protruding from a designed or necessary part of the bottom mold 3, with a horizontal or oblique through-hole 11 provided on its side surface.

FIG. 6 shows a state in which a horizontal or diagonal hole 13 is provided on at least one side of the bottom mold 3 with a protrusion 10 protruding from a design or a necessary part.

FIG. 7 shows a protrusion that is substantially similar to the protrusion 10 in FIG.
3 is provided.

As shown in FIG. 1, a bottom mold 3 has protrusions 10 protruding from a part of the bottom design or a necessary part on the upper surface of the bottom mold 3,
The primary outsole material is injected from the first injection hole 4 into the primary cavity 5' formed by the dummy mold 1 and the horizontal molds 2, 2, and the primary outsole 5 is formed.

Next, the horizontal molds 2, 2 are opened left and right and the dummy mold 1 is removed, and as shown in FIG. The secondary outsole material is injected from the second injection hole 9 into the secondary cavity 8' formed by 2, 2, and the secondary outsole 8 is formed.

After the secondary outsole 8 is formed, the horizontal molds 2, 2 and the sole mold 3 are opened, and the last 7 is removed to obtain an injection molded shoe having the outsole 5, 8.

The materials for the primary and secondary outsole can be any resin that is normally used in injection molding, such as polyvinyl chloride, and different materials may be used as long as the primary and secondary materials are compatible. It may be formed in a different color.

Conventionally, as shown in FIG. 4, after the primary outsole 5 is formed in the primary cavity 5', the horizontal molds 2, 2
is opened, and then when the dummy mold 1 is opened, the primary outsole 5 placed on the bottom mold 3, especially the end part, attaches to the lower surface of the dummy mold 1 and is pulled up halfway and returned to its original state. In many cases, a gap 12 is created without any gap.

Therefore, a second cavity 8' is formed by the bottom mold 3 on which the primary outsole 5 having the gap 12 is placed, the last 7 in which the sleeve 6 is fitted, and the horizontal molds 2, 2. When the secondary outsole material is injected through the second injection hole 9, this secondary outsole material fills the gap 12.
It was not possible to obtain the desired primary outsole 5 and secondary outsole 8 which had a layered shape with flat sides as shown in FIG.

Therefore, in order to prevent the above-mentioned gap 12 from occurring,
The design and protrusions 10 provided on the bottom mold 3 used in the present invention are illustrated in FIGS. 5 to 7.

The protrusion 10 shown in FIG. 5a is provided to protrude from the design surface of the bottom mold 3, and the size or shape of the protrusion 10 is appropriately designed to match the design.

For example, a cylinder with an outer diameter of 2 to 3 mm and a height of 2 to 5 mm is provided with a through hole of 1 to 2 mm in diameter in the horizontal direction, or a rectangular parallelepiped with a length of 1.5 to 5 mm, a width of 0.5 to 2 mm, and a height of 1.5 to 5 mm is provided horizontally. A through hole with a diameter of 1 to 2 mm in the direction is provided.

In addition, if one side of the through hole 11 is chamfered, when the horizontal molds 2, 2 and the bottom mold 3 are opened after forming the main sole, the bottom material filled in the through hole 11 will be cut off from the other side. This eliminates unnecessary deformation of the primary outsole 5 and the secondary outsole 8, allowing the desired injection molded shoe to be obtained.

5b, c, and d exhibit the same effect as in FIG.
1 is provided diagonally. In Figure c, a through hole 11 is provided in the horizontal direction as in Figure A, and the through hole 1
The central part of 1 is narrowed.

As mentioned above, Fig. 6e shows a protrusion 10 protruding from the design or necessary part of the bottom mold 3, and holes 13 with a diameter of 1 to 2 mm are horizontally provided on both sides of the protrusion 10, as shown in Fig. f. is provided with a tapered hole 13, as shown in Figure g.
is provided with a diagonally downward hole 13.

Fig. 7h shows a protrusion 10 protruding from a design or necessary part of the bottom mold 3, and a widening hole 13 is provided on the upper surface of the protrusion 10, and Fig. 7h shows an inverted T-shaped protrusion 10 on the upper surface of the protrusion 10. A hole 13 is provided.

As mentioned above, the protrusion 10 is a design provided on the top surface of the bottom mold 3 or a protrusion protruding from the top surface, and the side surface may be perpendicular or sloped with respect to the top surface of the bottom mold 3. good. In short, as shown in FIGS. 5 and 6, a through hole 11 or a hole 13 is formed in at least one side of the projection 10, and a hole is formed in the upper surface of the projection 10 as shown in FIG. It was formed.

The protrusion 10 may be attached to the upper surface of the bottom mold 3 by any appropriate method as required. For example, the protrusion 1
The lower surface of the protrusion 10 is directly bonded to the required location on the upper surface of the bottom mold 3 with a metal adhesive, the lower part of the protrusion 10 is formed into a screw shape, and this is screwed and fixed to the upper surface of the bottom mold 3.
Alternatively, attachment by welding or caulking can be considered.

In the present invention, by providing a through hole or a hole in at least one of the sides of the design or protrusion protruding on the top surface of the bottom mold, or the top surface, when the dummy mold is released from the primary outsole, the primary outsole is fixed to the bottom. Since the design on the top surface of the mold 3 or the through holes or holes provided in the projections are filled with the material for the primary outsole and are integrated, part or all of the top surface of the primary outsole is attached to the bottom surface of the dummy mold. Even by injection molding the secondary outsole, it is possible to obtain an injection molded shoe having the desired two layers on the side circumferential surface of the outsole without causing any displacement or lifting.

In addition, when opening the dummy mold, the primary outsole is securely fixed to the design surface of the bottom mold, so the worker can proceed with the work without worrying about the primary outsole lifting up. , it has become possible to eliminate the mental burden on workers and shorten work time.

Further, in the present invention, if the design is protruding from the top surface of the bottom mold, it can be formed by an extremely simple operation of just providing a through hole or a hole on the side or top surface of the design, and the design can be processed. If this is not desired, it is sufficient to simply protrude another protrusion with a through hole or hole on the side or top surface at an appropriate location on the top surface of the bottom mold. It can be used for bottom mold design.

Further, in the present invention, by providing a through hole or a hole in the design or protrusion protruding from the upper surface of the bottom mold, a cushioning effect can be exerted, and it is possible to reduce the impact particularly when stepped on.

[Brief explanation of drawings]

1 to 3 are explanatory diagrams showing the manufacturing process of injection molded shoes of the present invention, FIG. 4 is an explanatory diagram of a manufacturing process of injection molded shoes using a conventional sole mold, and FIGS. FIG. 7 is an explanatory sectional view of a protrusion provided on the upper surface of the bottom mold. 1...Dummy type, 2...Horizontal type, 3...Bottom type, 4...First
Injection hole, 5...primary bottom, 5'...primary cavity,
6...Flip cover, 7...Last, 8...Secondary outsole, 8'...Secondary cavity, 9...Second injection hole, 10...Protrusion, 1
1... Through hole, 12... Gap, 13... Hole.

Claims (1)

[Scope of Claims] 1. In a method for manufacturing injection molded shoes that uses a dummy mold and stamps twice, a through hole is formed on the upper surface of the sole mold at least in a part of the sole design or on the side surface of a protrusion protruding from a necessary part. A method for manufacturing injection molded shoes, characterized by using a provided sole mold. 2. The method for manufacturing injection molded shoes according to claim 1, characterized in that a sole mold having a hole provided on at least one side of the protrusion is used instead of the through hole. 3 In a manufacturing method for injection molded shoes that uses a dummy mold and is stamped twice, a sole in which a hole that widens toward the end is provided on the upper surface of at least a part of the sole design or a protrusion that protrudes from a necessary part on the upper surface of the sole mold. A method for manufacturing injection molded shoes, characterized by using a mold.