JP2928464B2 - Mold for molding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding die used for vulcanization molding of a spherical rubber body such as a liquid center (liquid core) for a golf ball.

[0002]

2. Description of the Related Art Generally, golf balls are wound balls,
The wound balls can be roughly classified into two-piece balls, one-piece balls, etc., and wound balls have a solid center type with a solid rubber center and a liquid material (water, aqueous solution, water dispersion, paste, other Liquid center type) in which a liquid or the like is enclosed.

[0003] However, in the liquid center type,
It is manufactured by molding an unvulcanized spherical rubber body a as shown in FIG. 9C and then vulcanizing and molding the unvulcanized spherical rubber body a.

That is, as shown in FIG. 9A, an unvulcanized spherical rubber body a is first formed into a spherical pellet b formed by freezing a liquid material, and the pellet b is formed into two uncured spherical pellets. The upper and lower molds d and e are brought close to each other with the vulcanized rubber sheets c and c interposed therebetween, and as shown in FIG.
Is formed by pressing off. The unvulcanized spherical rubber body a has a football shape as shown in FIG.

[0005] The spherical rubber body a is vulcanized by a vulcanizing mold having upper and lower dies g and h, as shown in FIG. At this time, as shown in FIG.
It is loaded into the mold to coincide with the vertical plane.

[0006]

However, during vulcanization,
If air is not sufficiently removed from the hollow portions formed by the upper and lower molds g and h, the inner surfaces of the hollow portions (the inner surfaces of the hemispherical recesses i and k of the upper and lower molds g and h) and the spherical rubber body a Then, air accumulates between them, and a recess (bear m) is formed in the product s as shown in FIG.

Further, the unvulcanized spherical rubber body a is vulcanized and molded after the frozen pellet b inside is thawed, but if pressed immediately after thawing, the outside of the rubber body a is dewed. Because of the so-called wet state, the hemispherical recesses i, k
The pressure of water vapor is generated between the rubber member a and the rubber member a, and as shown in FIG.
Is formed, and there is a risk that the liquid material inside leaks. In FIG. 11, p is a parting line formed during vulcanization molding.

Therefore, in the present invention, FIG.
An object of the present invention is to provide a molding die capable of preventing the occurrence of defects as described in (1).

[0009]

Means for Solving the Problems In order to achieve the above object, a molding die according to the present invention is a molding die for vulcanizing a spherical rubber body enclosing a liquid material. An upper mold and a lower mold in which a plurality of partial molds each having a hemispherical recess are arranged, and one of the mating surfaces where the upper mold and the lower mold contact each other has a width dimension. And a depth of 0.02 to 0.06 mm.

Another molding die according to the present invention is a molding die for vulcanizing a spherical rubber body enclosing a liquid material, which is a partial mold having a hemispherical recess. Equipped with a plurality of upper and lower dies, each with an air vent groove formed on the mating surface where the upper and lower molds abut, and abuts each other at the mating surfaces In this state, the vertical depth of the air vent groove is 0.02 to 0.06 mm, and the width is 1 to 5 mm.

The number of air vent grooves formed in one partial mold is 1 to 10, preferably 4 to 8.

[0012]

[Function] Since air vent grooves are formed in one or both of the mating surfaces of the upper and lower partial molds, when vulcanizing and molding an unvulcanized spherical rubber body, the upper and lower partial mold hemispheres are used. Air and water vapor between the inner surface of the valley and the spherical rubber body can escape from the air vent groove.

The air vent groove has a width of 1 mm.
5mm and its depth (total depth if the upper and lower partial molds have air vent grooves) is 0.02 to 0.06mm, so during vulcanization molding, (air and water vapor can escape At the same time) rubber does not protrude into the air vent groove.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings showing embodiments.

FIG. 1 shows a molding die according to the present invention, which has an upper die 1 and a lower die 2 and has a spherical rubber body 3 such as a solid center for golf balls (see FIG. 5). ) Is used for vulcanization molding. As shown in FIG. 4, the upper mold 1 and the lower mold 2 have partial molds 5 and 6 each having a hemispherical recess 4 having a radius R.
... are provided. That is, as shown in FIG. 3, several tens of partial molds 5 are arranged on the plate 7 or 8 in a lattice at a predetermined pitch.
Or 6 are respectively incorporated and arranged. .. May be arranged in a staggered manner.

Thus, the lower surface of the partial mold 5, ie, the mating surface 9, protrudes below the lower surface of the plate 7, and the upper surface of the partial mold 6, ie, the mating surface 10, protrudes above the upper surface of the plate 8, The partial mold 5 and the partial mold 6 can be approached and separated from each other.

Therefore, when the mating surfaces 8 and 9 are in contact with FIG. 1, a hollow portion 11 is formed in the upper and lower hemispherical recesses 4 and 4, and a gap 12 between the plates 7 and 8 is formed. Is formed.

Thus, as shown in FIGS. 1 and 2, a radial air vent groove is formed on the mating surface 10 of the partial mold 6 of the lower mold 2.
13 are arranged at a 90 ° pitch in the circumferential direction.

The air vent groove 13 connects the hollow portion 11 and the gap 12 when the upper and lower dies 1 and 2 are overlapped, and has a width W of 1 to 5 mm. The depth H is set to 0.02 to 0.06 mm.

Therefore, if the spherical rubber body 3 in which the liquid material is sealed is vulcanized in this molding die, the air and water vapor in the hollow portion 11 will be released during the vulcanization. ... to the outside to prevent the failure shown in FIG. 11 from occurring, and as shown in FIG.
A high quality liquid center for golf balls having no opening formed at 14 is obtained. (In FIG. 5, reference numeral 15 denotes a parting line formed during vulcanization molding.)

In other words, if the width W of the air vent groove 13 is less than 1 mm and the depth H is less than 0.02 mm,
Air and water vapor cannot be sufficiently removed, resulting in the failure shown in FIG. Conversely, the width W exceeds 5 mm and the depth H
If it exceeds 0.06 mm, the protruding portion 16 is generated as shown in FIG. 8, and the liquid material leaks, and a bonding failure (opening) occurs at the joint of rubber.

Next, Table 1 shows the width W of the air vent groove 13.
And various molds having different depths H are manufactured, and these molds are used to form a spherical rubber body 3 in which a liquid material is sealed.
The results of examining the presence or absence of defects by vulcanizing the resin were shown.

[0023]

[Table 1]

In Table 1, the product of the present invention has a width W of 1 mm and a depth H of 0.03 mm. The product of the present invention has a width W of 2 mm and a depth H of 0.02 mm. The width W is set to 3 mm, the depth H is set to 0.03 mm, the product of the present invention is set to the width W of 3 mm, the depth H is set to 0.06 mm, and the product of the present invention is set to the width W of 4 mm and the depth H The height H is set to 0.04 mm, the product of the present invention has a width W of 5 mm, the depth H is set to 0.03 mm, and the product of the present invention has a width W of 5 mm and a depth H of 0.05 mm.
mm. In addition, in each invention, air vent grooves 13 were formed at a 90 ° pitch along the circumferential direction on the mating surface 10 of the partial mold 6 of the lower mold 2. Then, each of the molds was vulcanized and molded into 300 pieces, and the surface of the unvulcanized spherical rubber body was kept wet.

As can be seen from Table 1, a defect (FIG. 11)
(B), as shown in (a), and (B, an opening in the joint as shown in (B) of FIG. 11), the width W is 1 to 5 mm and the depth is H
Does not occur at all when a mold having an air vent groove 13 with a thickness of 0.02 to 0.06 mm is used.

The defect in Table 1 means that the rubber protrudes into the air vent groove 13 at the time of vulcanization molding, and the rubber protruding portions 16 are formed as shown in FIG. It was defective, and there was a possibility that the internal liquid material might leak out.

Further, Table 2 shows that the conventional mold having no air vent groove 13 and the conventional mold having the air vent groove 13 have a width W and a depth H different from those of the air vent groove 13 of the present invention. The results of examining the presence or absence of defects by vulcanizing the spherical rubber body 3 using the mold that has come off are shown.

[0028]

[Table 2]

In Table 2, the conventional product is a case where no air vent groove is provided and the surface of the spherical rubber body is dry during vulcanization. The case where the surface of the spherical rubber body is wet at the time of sulfurization, the comparative product has a width dimension W of the air vent groove of 1 mm, the depth H is 0.01 mm, and the comparative product has the air vent groove of the air vent groove. The width W is 1 mm, the depth H is 0.07 mm, and the comparative product has a width W of the air vent groove of 5 mm and a depth H of 0.
01 mm, and the comparative product has a width dimension W of the air vent groove of 5 mm.
mm, the depth H is 0.07 mm, and the comparative product has a width W of the air vent groove of 3 mm and a depth H of 0.1 mm. In each of these cases, vulcanization molding was performed for each 300 pieces.
In addition, the surfaces of the spherical rubber bodies of the comparative products are wet.

Therefore, the conventional product and the comparative product have many defects and defects, and the comparative product has many defects. In other words, the air vent groove 13 is too small in the comparative product, the air vent groove 13 is too shallow in the comparative product, air or water vapor does not sufficiently escape, and defects occur. The groove 13 was too large, and the rubber leaked out into the groove 13 for air bleeding, causing a defect.

Next, FIG. 6 shows another embodiment. In this case, the width W is 1 to 1 on the mating surface 9 of the partial mold 5 of the upper mold 1.
The air vent grooves 13 having a depth of 5 mm and a depth H of 0.02 to 0.05 mm are formed at a 90 ° pitch along the circumferential direction.

Therefore, also in this case, in the superposed state, the hollow portion 11 and the gap 12 are communicated and connected by the air vent grooves 13 so that air or water vapor escapes during vulcanization molding.
Does not cause product defects.

FIG. 7 shows another embodiment. In this case, air vent grooves 13, 13 are formed in the partial mold 5 of the upper mold 1 and the partial mold 6 of the lower mold 2, respectively. In this case, the upper and lower air-release grooves 13, 13 is mutually corresponding, the sum of the depth H ₂ of the depth H ₁ and the lower groove 13 of the upper groove 13, that is, 0.02 to 0.05 mm depth H And Of course, the width dimension W of the grooves 13, 13 is 1 to 5 mm.

Therefore, also in this case, at the time of vulcanization molding, air and water vapor can escape from the air vent grooves 13 and 13 and no defect occurs in the product.

The number of air vent grooves 13 formed in one of the partial molds 5 and 6 is not limited to four, but may be one to ten, preferably four to eight. . ,
That is, if the number of the air vent grooves 13 is too large, the probability of rubber exuding increases, which is not preferable.

[0036]

Since the present invention is configured as described above, the following effects can be obtained.

At the time of vulcanization molding, water and water vapor can be discharged from the concave portion of the partial mold through the air vent groove.
High quality products can be reliably provided.

The width of the air vent groove is set to 1
It has a depth of up to 5mm and a depth of 0.02 to 0.06mm (when the upper and lower partial molds have air vent grooves). No leakage occurs, the liquid material inside does not leak, and the opening n (FIG. 11) does not occur, and a normal product can be stably provided.

There is also an advantage that the mold as a whole can be easily manufactured without complication.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a main part showing an embodiment of the present invention.

FIG. 2 is an enlarged plan view of a lower partial mold.

FIG. 3 is a plan view of a partly broken main part.

FIG. 4 is a sectional view showing a state where an upper mold and a lower mold are separated.

FIG. 5 is a perspective view of a spherical rubber body after vulcanization.

FIG. 6 is an enlarged sectional view of a main part showing another embodiment.

FIG. 7 is an enlarged sectional view of a main part showing another embodiment.

FIG. 8 is a perspective view showing a defective product.

FIG. 9 is a production process diagram of an unvulcanized spherical rubber body.

FIG. 10 is a cross-sectional view of a conventional molding die.

FIG. 11 is a perspective view showing a defective product.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper mold 2 Lower mold 3 Spherical rubber body 4 Hemispherical recess 5 Partial mold 6 Partial mold 9 Mating surface 10 Mating surface 13 Air vent groove

Claims (2)

(57) [Claims] 1. A molding die for vulcanizing a spherical rubber body 3 enclosing a liquid material, comprising a plurality of partial molds 5, 6,... A mold 1 and a lower mold 2 are provided, and one of the mating surfaces 9 and 10 where the partial mold 5 of the upper mold 1 and the partial mold 6 of the lower mold 2 contact each other has a width of 1 mm.
Molding the air-release grooves 13 and 0.02~0.06mm depth with a to 5 mm, and the number of the air-release groove 13 is 4
A molding die, characterized in that the number is up to eight . 2. A molding die for vulcanizing a spherical rubber body 3 enclosing a liquid material, comprising a plurality of partial molds 5, 6,... A mold 1 and a lower mold 2 are provided. Air bleed grooves 13 and 13 are formed in mating faces 9 and 10 where the partial mold 5 of the upper mold 1 and the partial mold 6 of the lower mold 2 are in contact with each other. The total vertical depth of the air vent grooves 13, 13 in a state where they contact each other at 9, 10 is 0.02 to 0.06 mm
And the width is 1 to 5 mm , and the air
A molding die, characterized in that the number of punching grooves 13 is 4 to 8 .