JPS63214270A - Production of ball for ball game - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a ball game ball which is formed by forming a thread-wound reinforcing layer on a rubber tube, and forming an outer eyebrow made of a multilayer thermoplastic elastomer on the outer periphery of the reinforcing layer. Regarding the manufacturing method.

<Prior art> Balls for ball games, such as parley balls, soccer balls, basketball balls, etc., having a rubber tube, a thread-wound reinforcing layer, a middle rubber layer, and a leather skin layer are manufactured through the steps shown in FIG. be done. That is, first, a sheet-like rubber is formed into a dupe made of a hollow spherical body, and this is heated to about 170°C to vulcanize it, and then several thousand meters of nylon thread or the like is wound on a continuous track around the tube surface to form a reinforcing layer. form. This reinforcing layer provides the ball with sphericity, durability, and dimensional stability. Next, this reinforcing layer is covered with a thin rubber layer called the middle layer, and after applying an adhesive (rubber paste) to this surface, multiple leather panels (natural leather or synthetic leather panels) are glued together. and complete it.

<Problems to be Solved by the Invention> In the above manufacturing method, after forming the reinforcing layer, an inner patch forming process, an adhesive coating process, and a leather panel bonding process are required, and these steps require manual labor. It was a time-consuming task. Especially when bonding leather panels, for example,
In the case of a sunker ball with a hexagonal pattern, there are 12 fives.
A rectangular leather panel and 20 hexagonal leather panels with adhesive applied to their backs are arranged in a gap on the inner surface of a hemispherical carving mold, and the ball base coated with adhesive is accommodated and compressed to form the surface of the ball base. The 32 leather panels mentioned above are glued together.This work is done by hand, and defects such as panel misalignment are likely to occur, and work time and work accuracy greatly depend on the ability of the worker. There was a problem with being exposed.

The present invention was made to solve these problems, and it replaces the latter three steps with a new method that is different from the conventional method, improving work efficiency, shortening work time, and automating work. It is something.

<Means for Solving the Problems> The method for manufacturing a ball game ball according to the present invention includes a step of extruding a parison containing a thermoplastic elastomer having wear resistance and weather resistance through an extrusion die, and a step of extruding a parison containing a thermoplastic elastomer having wear resistance and weather resistance, and a step of extruding a parison containing a thermoplastic elastomer having wear resistance and weather resistance. A hollow spherical ball base, which is provided with reinforcing properties and is held in a spherical shape by being filled with air at a constant pressure, is placed in the hemispherical hollow portions of the two molds, and the ball base is enclosed therein. The step of introducing the parison between the molds as shown in FIG. and the step of sucking the air existing between the two molds, and the step of separating the two molds and taking out the hollow ball formed into a spherical shape, and stretching the parison into a spherical shape using the surface of the ball base. This suppresses the flow of the parison in the spherical direction and makes the thickness of the parison uniform.

<Example> An example will be described below in which a three-layer parison is extruded and coated in a spherical shape on the surface of a ball base to form an outer layer.

In FIG. 1, 1 is a coextrusion die with three injection holes 2a,
2b, 2c, and these injection holes 2a, 2b,
Thermoplastic resin is supplied to 2c by an extruder (not shown). 3 is a mandrel, which has a minute gap formed between it and the coextrusion die 1, and has injection holes 2a, 2b, 2c.
The injected resin is extruded downward in the figure as a three-layer parison 4 (6). A styrenic thermoplastic elastomer having wear resistance and weather resistance, such as Turuprene (registered trademark, manufactured by Asahi Kasei Industries, Ltd.), is supplied to the injection hole 2a to form the innermost N5 of the parison 4. A saponified ethylene-vinyl acetate copolymer is supplied to the injection hole 2b to form the adhesive N6. Further, the injection hole 2C is supplied with a thermoplastic elastomer having wear resistance, weather resistance, and good gloss, such as Takerank (registered trademark, manufactured by Takeda Pharmaceutical Company Limited), which is a polyurethane thermoplastic elastomer. 40 epidermal layer 7 is formed. Here, the thickness of the innermost layer 5 is
Approximately 1.5 fins to 2.0 fins, thickness of adhesive layer 6 is approximately 20
μ, the thickness of the skin layer 7 is approximately 10 μ. The adhesive layer 6 is
This is for adhering the innermost layer N5 and the skin layer 7. Further, the inner diameter of the parison 4 is determined in accordance with the diameter of the ball, and in the case of a soccer pole, approximately 22 cm is appropriate.

8a.

8b is a mold that is separated from the parison 4 at a distance slightly larger than the diameter of the parison 4 below the lead-out part thereof, and has hemispherical cavities 9a and 9b formed on opposing surfaces thereof. 10.10 is a blade formed on the edge of the cavities 9a, 9b, and 11.11... is a large number of minute holes formed on the surface of the cavities 9a, 9b for sucking air. 12 is a pipe connected to a vacuum pump. The inner surfaces of the cavities 9a and 9b are formed with a concavo-convex pattern (not shown) that is an inversion of the pattern on the surface of the ball. For example, in the case of a soccer ball, the boundaries of the pentagonal and hexagonal patterns are formed into protrusions. It is formed.

Reference numeral 13 denotes a ball base consisting of a hollow spherical rubber tube 18 and a reinforcing layer 14 made of a thread wound, and is supported by a support 15. This support 15 is inserted into an air injection valve 16 (FIG. 2) of the ball base 13. Reinforcement Ji
As described above, t14 is made of several thousand meters of nylon thread wound, forming an uneven resistance surface.

2 to 6 show the manufacturing method according to the present invention in the order of steps, and will be explained below according to the figures.

A) The molds 8a and 8b are in an open state, and the three-layer parison 4 is descending from above with the arrow a), and the support 15 is coming from below.
The ball base 13 supported by the molds 5a and 8b is raised and placed between the molds 5a and 8b (arrow EI]b). This ball base 13 is wrapped within the parison 4 (FIG. 2).

The mouth and parison 4 stop descending, and the molds 8a and 8b move in the direction of overlapping each other (arrow C).

The blades of the molds 8a and 8b contact the outer surface of the parison 4,
The parison 4 is pressed inward, and the inner surface of the parison 4 contacts the ball base 13 and begins to deform along the spherical surface of the ball base 13 (FIG. 3).

C. The distance between the molds 8a and 8b is further narrowed and the parison 4
is in close contact with a considerable area of the surface of the ball base 13. The parison 4 tries to extend to the greatest extent at point A, but the resistance surface of the reinforcing layer 14 suppresses its extension in the spherical direction. At the same time or before the parison 4 completely cools down the cavities 9a and 9b, the vacuum pump is activated to cool the air inside the cavities 9a and 9b and the holes 1.
It is released to the outside via 1°11... This suction must not be so strong as to pull the parison 4. The ball base 13 is filled with compressed air in advance and maintains its spherical shape, so it does not deform even when force is applied from the parison 4 (FIG. 4).

2. After the molds 8a and 8b are crimped, the parison 4 is cut by the blade 10.10 to form the ball exterior N17. At the same time, the thermoplastic elastomers are bonded together by mold clamping force (approximately 5 kg/cJ). During this crimping process, higher pressure air is blown into the tube 18 from the support 15 to bond the outer layer 17 so as to bite into the reinforcing layer 14, thereby improving the bonding strength and simultaneously increasing the bonding strength of the outer layer 17.
7. Ensure that the pattern is formed on the surface (Fig. 5).

E. After cooling, the molds 8a and 8b are opened and the support 15 is lowered together with the ball 19 (FIG. 6). After that, the support 15 is pulled out from the ball 19, a rubber band is attached, and air is injected to complete the ball.

In the above manufacturing method, a black thermoplastic elastomer sheet is arranged in a part of the pattern, for example, in the case of a sunker ball, a pentagonal pattern part, and the parison 4
If the color of the skin N7 is white, the manufactured ball will have a black pentagonal pattern. Further, this coloring can be applied to characters and the like in the same manner.

In the above embodiment, an example was explained in which the three-layer parison 4 was used to constitute the innermost layer 5, the adhesive layer 6, and the skin N7 as the outer layer N17, but instead of this, only the single layer of the skin layer 7 is used. It is also possible. In this case, epidermis N7
As the material, the aforementioned polyurethane thermoplastic elastomer with excellent wear resistance and weather resistance, such as Takerank (
(registered trademark) is suitable.

Further, in the above embodiment, the reinforcing layer 1 of the ball base 13
Although the example in which 4 is a thread-wound layer has been described, instead of this, a structure may be adopted in which a strip-shaped piece of woven fabric is attached to a rubber tube or sewn into a spherical shape to form a cloth layer, and the rubber tube is wrapped with this cloth layer. It can also be used, in which case the weave of the fabric forms a resistive surface.

Further, as the ball base 13, a polyester thermoplastic elastomer such as Hytrel (registered trademark) or Glilux (registered trademark) is formed into a hollow spherical tube by rotational molding or injection molding, and the surface of the tube is roughened. It can be a resistive surface. This surface roughening can be easily achieved by roughening the surface of the mold.

<Effects of the Invention> The method for manufacturing a ball for ball games according to the present invention is characterized in that a parison extruded from a coextrusion die is
Since the outer layer is formed on the ball base by introducing it between two molds, pressing and clamping it, the inner layer forming process and adhesive coating process that were necessary in the conventional manufacturing method, It becomes possible to replace the leather pasting and forming process with a single process, and the work can be automated. This makes it possible to shorten working time and significantly reduce the occurrence of defects.

According to the invention, since the parison is pressed onto the ball base which acts as a resistive surface, the flow of the parison in the direction of the ball's spherical surface is minimized and an overall uniform outer layer can be obtained. .

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view for explaining the manufacturing method according to the embodiment of the present invention, FIGS. 2 to 6 are cross-sectional views for explaining the same side in the order of steps, and FIG. 7 is a conventional manufacturing method. FIG. 2 is a block diagram illustrating the method. 1... Coextrusion die 2a, 2b, 2c... Injection hole 3... Mandrel 4... Parison 5...
Innermost layer 6... Adhesive layer 7... Epidermis N
8a, 8b... Mold 9a, 9b... Cavity 10... Blade 11.11... Hole 1
3...Ball base 14...Reinforcement layer 15...Support

Claims (8)

[Claims] (1) A process of extruding a parison containing a thermoplastic elastomer having wear resistance and weather resistance from an extrusion die, and reinforcing properties are imparted to the hemispherical hollow portions of two molds having opposing hemispherical hollow portions. At the same time, a hollow spherical ball base filled with air at a constant pressure and held in a spherical shape is arranged.
a step of introducing the parison between the molds so as to enclose the ball base; overlapping the two molds and pressing the parison against the surface of the ball base; simultaneously forming a plurality of parisons on the surface of the mold; A step of suctioning the air existing between the parison and the mold through the suction hole of the parison, a step of separating the two molds and taking out a hollow ball molded into a spherical shape, and holding the surface of the ball base to the parison. A method for producing a ball for a ball game, characterized in that by stretching the parison into a spherical shape, the flow of the parison in the spherical direction is suppressed, and the thickness of the parison is made uniform. (2) The parison has an innermost layer made of a styrene thermoplastic elastomer having wear resistance and weather resistance, and an adhesive layer made of a saponified ethylene vinyl acetate copolymer.
The method for producing a ball game ball according to claim 1, wherein the ball is a three-layer parison composed of a skin layer made of a thermoplastic polyurethane elastomer having wear resistance and weather resistance. (3) The method for manufacturing a ball game ball according to claim 1, wherein the parison is a single-layer parison made of a thermoplastic polyurethane elastomer having wear resistance and weather resistance. (4) The method for manufacturing a ball for a ball game according to claim 1, wherein the ball base has a resistance surface consisting of a large number of concavities and convexities. (5) Manufacture of a ball game ball according to claim 4, wherein the ball base is composed of a rubber tube and a wound layer formed by winding a thread on an endless track on the outer surface of the rubber tube. Method (6) The above-mentioned ball base is comprised of a rubber tube and a cloth layer formed by attaching a plurality of strip-shaped woven cloth pieces to the outer surface of the rubber tube or sewing them into a spherical shape. Method for manufacturing a ball game ball according to item 4 (7) The method for manufacturing a ball game ball according to claim 4, wherein the ball base is a hollow sphere made of a reinforcing thermoplastic elastomer whose outer surface has been roughened. (8) The method for manufacturing a ball game ball according to claim 7, wherein the hollow sphere is made of a polyester thermoplastic elastomer.