JPH09299514A - Device for applying adhesive agent to melton dumbbell for tennis ball - Google Patents

Abstract

PROBLEM TO BE SOLVED: To equally apply an adhesive agent without wasting it by providing a form enough for sealing a melton dumbbell into the cavity of a lower die for an upper die, and an adhesive agent passage for introducing the adhesive agent into a gap between the melton dumbbell of the lower die and the peripheral edge of the cavity. SOLUTION: A melton dumbbell 3 is fitted to a cavity 4 of a lower die 2 preferably while turning the face in contact with the surface of a ball downward, and the melton dumbbell 3 is compressed and fixed by an upper die 1. The lower die is provided with an airhole 14, one of the upper die 1 or the lower die 2 is provided with an 0 ring 13 for preventing the adhesive agent from being leaked and inside the upper die 1, the injection passage for the adhesive agent is provided on a top plate from an injection port 5 to an injection groove. Then, the seam adhesive agent quantitatively injected from the seam adhesive agent injection port 5 through a syringe or an injection instrument is injected from the adhesive agent injection groove to the gap between the lower die 2 and the melton dumbbell 3 and applied. In this case, the quantity to be applied is determined by the length of a guide fin 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for compressing and fixing a melton dumbbell for a tennis ball in a mold and injecting a seam adhesive to apply the adhesive uniformly and without waste.

[0002]

2. Description of the Related Art Tennis balls are cocoon-shaped on the outer circumference of a rubber ball.
It is formed by adhering two sheets of outer skin (melton dumbbells), but the adhesive that fills the gap between the outer skins and joins the outer skins is thickly applied in advance over the entire length of the outer peripheral edge of both melton dumbbells. .

Conventionally, in order to apply an adhesive such as rubber glue to the outer peripheral edge of the melton dumbbell, a plurality of outer skins are laminated to form a unit pack, and the outer peripheral surface of the unit pack is brushed or roller-applied. Alternatively, as shown in FIG. 7, a method of holding a dumbbell pack 32 between a pair of sandwiching plates 31 and 31 and immersing it in a rubber paste tank 33 is adopted. However, in the former method, since the amount of the rubber glue that adheres to the periphery of the pack in one application is small, it is necessary to wait for the rubber glue to dry before repeatedly applying it, which is troublesome. In the latter method, the adhesion amount of the rubber glue varies between the lower side and the upper side of the pack. That is, the dumbbell near the bottom side of the rubber glue tank has a larger amount of rubber glue permeation than the dumbbell near the liquid surface due to the liquid pressure of the rubber glue. Therefore, if the immersion time is determined so that the adhesive amount of the lower dumbbell is optimal, the amount of the upper dumbbell attached will be insufficient.

Further, it is not easy to orderly bundle the woven fabric meltons, and the dripping of the adhesive causes uneven application of the adhesive, and waste of the adhesive due to the adhesion of the adhesive to metal fittings used for packing. There was a problem such as doing.

[0005]

SUMMARY OF THE INVENTION The present invention solves the problems associated with the application of an adhesive to a conventional tennis ball melton dumbbell as described above, and provides an apparatus for applying the adhesive uniformly and without waste. It is a thing.

[0006]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the inventors of the present invention inserted a melton dumbbell into a lower mold having a cavity slightly larger than the melton dumbbell, and pressed it with the upper mold. The inventors have found that the adhesive is applied uniformly and without waste by applying the seam adhesive by fixing and injecting the adhesive from the upper mold into the gap.

That is, the present invention comprises an upper die and a lower die,
The lower mold has a cavity having a depth in which the melton dumbbells having the shape of a tennis ball melton dumbbell enter several to several tens, and the cavity is 0.1 to 3 mm outside the melton dumbbell to be inserted into the cavity. Wide,
In addition, a plurality of guide pins are formed at predetermined intervals from the peripheral portion of the cavity toward the inside, and the shape formed by the inner surface of the guide pin is substantially the same as the melton dumbbell. When inserted into the cavity, a gap formed by a guide pin is formed between the melton dumbbell and the periphery of the cavity, and the upper die has a shape sufficient to enclose the melton dumbbell in the cavity of the lower die and the outer die. Seam adhesive for tennis ball melton dumbbells, characterized in that it has an adhesive passage for introducing the adhesive into the gap formed between the lower mold melton dumbbell and the cavity peripheral edge through the upper mold Application device.

The present invention will be described in more detail with reference to the drawings. FIG. 1 is an exploded perspective view of a mold of the present invention. The adhesive application device of the present invention is basically composed of an upper mold 1 and a lower mold 2, and the lower mold 2 has several Melton dumbbells to several 1
There is a cavity 4 that contains 0 sheets.

FIG. 2 is a perspective view of the upper mold 1 as seen from the cavity side, and FIG. 3 shows the lower mold of FIG. 1 cut along the line A '.
It is the perspective view seen from the cut surface. An injection port 5 for injecting an adhesive is present outside the upper mold 1, and the adhesive injected from the injection port reaches an adhesive injection groove 6 shown in FIG. Injected inside. Upper mold 1
May be provided with projections 7 at the four corners in order to improve the compatibility with the lower mold and the hermeticity, and the lower mold 2 may have recesses 8 corresponding thereto at the four corners. The injection groove existing in the upper mold 2 has a groove shape in the drawing shown here, but it is not necessarily limited to this. If necessary, there may be only a plurality of injection ports communicating with the injection port 5. The structure of the injection groove shown in FIG. 2 will be clarified in the drawings described later. Briefly, there is another cavity into which the top plate 9 is inserted in the upper mold 1, and the top plate 9 is fixed with screws 10 at intervals.

A guide pin 11 having a predetermined shape is present in the lower mold 2, and the shape formed by the inner surface of the guide pin is substantially the same as that of the melton dumbbell 3. Guide pin 1
The shape of 1 is not particularly limited, and may be a rectangular shape as shown in FIG. 3 or a shape as shown in FIG. The guide pin is important because its presence forms an adhesive layer between the end of the melton and the cavity, so that this width d determines the width of the adhesive layer. The width d of the guide pin is 0.1 to 3 mm, preferably 0.4 to 0.6
mm, and if this width is too large, the amount of useless adhesive increases, and conversely, if it is too small, the distribution of adhesive deteriorates and the amount of adhesive applied increases. The depth h of this cavity basically corresponds to the height of the guide pin. The depth of the cavity may be the height when several to several tens of melton dumbbells are stacked. Specifically, it is 1.5 to 100 mm, preferably 2 to 8 mm. As for the depth of the cavity, the depth indicated by h is sufficient as described above.
As shown in 2, it is preferable that there is some margin. This allowance is due to the fact that Melton dumbbells are made of cloth, so some bulge is considered. However, to prevent the melton dumbbell from going below its depth h, an extra depth of 12
It is preferable that the portion (1) is provided with an inclination toward it so that the end of the melton dumbbell does not go below it, and the interval is preferably 0.1 to 4 mm. In addition, the lower mold 2 has an O-ring 13 for better sealing.
May be provided. Furthermore, the discharge port 14, which is an escape port for the air inside, may be formed to facilitate the injection of the adhesive 9.

Next, the structure of the upper mold 1 will be described with reference to FIGS. 5 and 6. FIG. 5 is a top perspective view of the upper mold 1. In this perspective view, the top plate 20 in the upper mold is removed from the upper mold. FIG. 6 is a perspective view of the upper mold 1 as seen from the top plate side, and in this case, the top plate does not exist. The upper mold 1 has a cavity 21 into which the top plate 20 is inserted. This cavity has a top plate 20 inserted and can be fixed with screws 22. Naturally, the top plate 20 has screw holes 23 corresponding to the screws 22. 5 shown in FIG. 6 is 5 shown in FIG.
It corresponds to and is the injection port of the adhesive. A groove is formed in the top plate 20 so that the adhesive injected from the adhesive injection port 5 flows to the end of the top plate, and the end of the top plate is bonded through the adhesive inside the groove. The adhesive flows from the agent injection groove into the lower adhesive gap. In FIG. 5, the top plate 20 is fixed by a dotted line. The method of using the top plate 20 described above is only one aspect of the present invention. Of course, as long as the adhesive is introduced into the adhesive gap in the cavity of the lower mold from the injection port 5 by using any means without using such a top plate, any form is possible. It may be. However, it is generally considered that the structure using the top plate as described above is the best from the viewpoints of various handling problems or easiness of manufacturing.

In a further preferred embodiment, similarly, the melton dumbbell 3 is fitted into the cavity of the lower mold 2 preferably with the surface in contact with the ball surface facing downward, and the melton dumbbell is compressed and fixed by the upper mold 1 as shown in FIG. As shown in FIG. 5, the lower mold is provided with an air hole 14, and the upper mold or the lower mold is provided with an O-ring 13 for preventing the leakage of the adhesive. The penetration amount of the adhesive into the melton dumbbell is controlled by the physical properties of the adhesive and the compression deformation amount of the melton dumbbell. Further, as shown in FIG. 5, a seam adhesive injection path is provided on the top plate 20 from the injection port 5 to the injection groove 6 in the upper mold 1, and the syringe, injection device, etc. are provided from the seam adhesive injection port 5. The seam adhesive which is quantitatively injected by the above is injected into the gap between the lower mold 2 and the melton dumbbell 3 through the adhesive injection groove 6 and applied. The coating amount at this time is the guide fin 11
Is determined by the length of. At this time, the top surface of the upper mold 1 is provided with a mounting surface for the top plate 20, as shown in FIG. Using this mold, a seam adhesive was actually applied to a melton dumbbell according to the application method of the present invention, and comparison was made with application by a dipping method.

[0013]

【Example】

(Example) An adhesive having the composition shown in Table 1 below was prepared,
It was applied to a melton dumbbell with the above mold and dried at 50 ° C. for 3 hours, and the average amount of adhesive adhered and the range (n = 40) of each melton dumbbell and the loss of adhesive were measured, and the results are shown in Table 2. Indicated.

(Comparative Example) Using the same adhesive as in the example, 50 Melton dumbbells were stacked, sandwiched between metal plates by top and bottom, and compressed with metal fittings. Dry for 4 hours, 4 each on top, middle and bottom
Sampling the sheet, average adhesive amount and range
(n = 120) and the loss of the adhesive were measured in the same manner as in Examples, and the results are shown in Table 2.

[0015]

[Table 1] Table 1 Components Solid content (%) Dry weight part Wet weight part Depolymerized natural rubber 53 100 188.7 Latex Acc.MZ (Note 1) 50 0.5 1.0 Acc.EZ (Note 2) 50 0.5 1.0 Sulfur 50 1.5 3.0 Zinc white 50 3.0 6.0 Titanium oxide 50 7.0 14.0 hi-Metroze 5 1.0 20.0 90SH-15000 (Note 3) (Note 1) 2-mercaptobenzothiazole (Note 2) Zinc diethyldithiocarbamate (Note 3) Manufactured by Shin-Etsu Chemical Co., Ltd. Water-soluble methyl cellulose

[0016]

[Table 2] Table 2 Item Example Comparative Example Adhesive adhesion amount (g) Upper average (R) -1.36 (0.39) Medium average (R) -1.50 (0.48) Upper average (R) -1.69 (0.64) All Average (R) 1.28 (0.21) 1.32 (0.64) Loss (g) 3 114 (Residue in injection channel) (Adhered to metal fitting)

As shown in Table 2, the adhesive adhesion amount of the melton dumbbell coated with the adhesive by the method of the present invention showed less variation than the comparative example, and the loss was also greatly reduced.

[0018]

By applying the seam adhesive to the melton dumbbell for tennis ball by the method of the present invention, the adhesive can be applied uniformly and without waste.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a mold used for applying an adhesive of the present invention.

FIG. 2 is a perspective view of the upper mold used for applying the adhesive of the present invention as seen from the cavity side.

FIG. 3 is a cross-sectional perspective view of a lower mold used for applying the adhesive of the present invention.

FIG. 4 is a diagram showing the shape of a lower guide pin used for applying the adhesive of the present invention.

FIG. 5 is a top perspective view of an upper mold used for applying the adhesive of the present invention.

FIG. 6 is a perspective view of a mold surface of an upper mold used for applying the adhesive of the present invention.

FIG. 7 is a mode in which a melton pack is immersed in rubber paste.

[Explanation of symbols]

1 ... Upper mold 2 ... Lower mold 3 ... Melton dumbbell 5 ... Pouring port 6 ... Injection groove 11 ... Guide fin 12 ... Height difference between bottom periphery of bottom mold cavity and bottom center 13 ... O-ring 14 ... Air Hole 20 ... Top plate 31 ... Stopper 32 ... Melton dumbbell pack 33 ... Rubber glue tank

Claims (1)

[Claims] 1. A lower mold comprising an upper mold and a lower mold, the lower mold having a cavity having a depth that allows several to several tens of melton dumbbells having the shape of a melton dumbbell for a tennis ball to be inserted therein. Wider outside by 0.1 to 3 mm than the Melton dumbbell inserted inside,
In addition, a plurality of guide pins are formed at predetermined intervals from the peripheral portion of the cavity toward the inside, and the shape formed by the inner surface of the guide pin is substantially the same as the melton dumbbell. When inserted into the cavity, a gap formed by a guide pin is formed between the melton dumbbell and the peripheral edge of the cavity, and the upper die has a shape sufficient to enclose the melton dumbbell in the cavity of the lower die and the outer die. Seam adhesive for tennis ball melton dumbbells, characterized in that it has an adhesive passage for introducing the adhesive into the gap formed between the lower mold melton dumbbell and the cavity peripheral edge through the upper mold Coating equipment.