JPH08300363A - Method and mold for production golf ball - Google Patents

Abstract

PURPOSE: To produce a golf ball having good appearace by forming the whole or part of a mold from a porous material having three-dimensional fine communication holes so that the communication holes can communicate with a cavity space to make air entraining inferiority hard to generate. CONSTITUTION: In a golf ball producing mold 1 having a hollow spherical cavity 2 formed therein, the whole or part of the lower mold 1b of the mold 1 is formed from a porous material 11 having a three-dimensional fine communication holes so that the communication holes can communicate with the space of the cavity 2. By this constitution, air in the cavity 2 can be certainly and smoothly discharged to the outside and air entraining inferiority is hard to generate and a golf ball having good appearance can be molded. Since the golf ball molded using this mold 1 has a satin like surface by the porous material 11, when painting is applied to the golf ball after molding, a surface reoughening process can be omitted or simplified and the close adhesiveness of a coating film is good.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for producing a golf ball, which is capable of smoothly discharging air in a mold cavity of a golf ball, and a method for producing a golf ball using the same.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
When a golf ball cover is injection molded, for example, as shown in FIG.
A mold as shown in 3 was used. That is, 1 in the figure is
A mold including an upper mold 1a and a lower mold 1b.
A hollow spherical cavity 2 is formed inside by a and 1b being separably joined to each other. Reference numeral 3 denotes a support pin, which is arranged in a support pin insertion hole 4 formed in each of the upper and lower molds 1a and 1b so as to be able to move forward and backward.
The core 5 is supported at the time of advancing to the side. Further, 6 is a gas vent hole, and a fixing pin 7 is arranged in the hole 5.

When a golf ball cover is injection-molded using such a mold, the upper and lower molds 1a and 1b are joined with the core 5 accommodated in the cavity 2, and the support pin 3 is moved in the cavity 2 direction. It is advanced to support the core 5 in the center of the cavity 2. Cavity 2 in this state
The cover molding material is injected and introduced into (the gap 8 between the cavity surface and the core surface), and when the gap 8 is filled with the cover molding material, the support pin 3 is withdrawn into the support pin insertion hole 4 to cover the cover. Is molded. In this case, the air in the cavity 2 (gap 8), when the cover molding material is introduced into the gap 8, the gap between the gas vent hole 6 and the fixing pin 7 and the support pin 3 and the support. It is discharged to the outside through the gap between the pin insertion hole 4.

However, the gap is 2/100 to 4
/ 100 mm, and if it is wider than 100 mm, the problem of burrs occurs. Therefore, since the above-mentioned gaps are narrow and the number of gaps is small, it is difficult for the air in the cavity to escape, and weld defects and air-entry defects are likely to occur. Therefore, if the gas is not vented well, the injection pressure must be increased in order to inject the resin. If the injection pressure is increased in this way, burrs are likely to occur and a large mold clamping force is required. Further, if the injection speed is increased, the air will not escape completely, and weld defects and air entry defects are likely to occur, which makes it difficult to form a thin cover.

On the other hand, when molding a one-piece golf ball, a two-piece ball core, a wound center ball, etc. by press vulcanization, a mold as shown in FIG. 14 was used. In order to prevent air accumulation, the weight of the molding material charged is made larger than the weight of the molded product, and the excess molding material is extruded from the mold cavity 2. But,
In this method, a large amount of molding material is wasted. Also,
In order to release air from the mold cavity 2, a bumping operation for slightly opening the mold may be performed at the beginning of vulcanization or during vulcanization. Such a bumping operation is performed by using a heat insulating plate attached to the hot platen. It was easily damaged.

When a cover of a thread-wound golf ball is compression molded, a hollow hemispherical cover material (half cup) is used.
Although the thread wound core was covered with, the cover was formed by applying temperature and pressure after closing the mold, but the core of the thread wound golf ball contains a lot of air, and in the gap with the mold with dimples. However, even if the above operation is performed, the air that expands due to the temperature when the cover is attached to the mold is not sufficiently discharged from the mold cavity, and air does not enter the cover surface or inside the cover. Was likely to occur. Further, in the case of compression molding of a cover of a solid golf ball, the core usually does not contain air, but if the shape and size of the half cup or the core are not appropriate, defective air injection may occur. As described above, if the shape of the molding material to be put into the cavity is not taken into consideration, defective air is likely to occur. In addition, discoloration due to gas burning may occur even if no air-entry defect occurs.

The present invention has been made in view of the above circumstances, and it is possible to reliably and smoothly discharge the air in the mold cavity to the outside, and to prevent defective air from entering and to have a good appearance. An object of the present invention is to provide a mold for manufacturing a golf ball, which can mold a golf ball, and a method for manufacturing a golf ball using the mold.

[0008]

SUMMARY OF THE INVENTION To achieve the above object, the present invention provides: In a mold for producing a golf ball having a hollow spherical cavity inside, the whole or a part of the mold is formed of a porous material having three-dimensional fine communication holes so that the communication holes can communicate with the cavity space. II. A mold for producing a golf ball, characterized by: While forming a hollow spherical cavity inside,
In a golf ball manufacturing mold in which a support pin supporting a core arranged in the cavity is provided so as to be able to move forward and backward, the support pin is formed of a porous material having three-dimensional fine communication holes. Mold for golf ball production III. A method of manufacturing a golf ball by supplying a molding material for a golf ball into a cavity of a mold, wherein the mold is the mold of I or II described above.

In this case, the following can be used as a preferred embodiment of the mold I described above. I-i The entire die is made of the above porous material I
Mold. I-ii A mold of I-i in which a plurality of layers of porous materials having fine communication holes having different pore diameters are sequentially laminated from the cavity side toward the outside. I-iii The main body of the mold is made of the above-mentioned porous material, and a surface layer made of a non-porous material in which through holes or slits are formed on the cavity side surface of the main body made of this porous material is laminated. Mold. I-iv A mold of I-iii in which a void is provided between the surface layer made of the non-porous material and the main body made of the porous material via a support body. I-v A mold of I in which the main body of the mold is formed of a non-porous material having a plurality of ventilation holes, and a surface layer made of the above-mentioned porous material is laminated on the cavity side surface of the main body. I-vi A mold of Iv in which a void is provided between the surface layer made of the porous material and the main body made of the non-porous material via a support body. The main body of the I-vii mold is made of a non-porous material having a plurality of ventilation holes, and an intermediate layer made of the porous material is laminated on the cavity side surface of the main body, and a through hole is further formed on the intermediate layer. Alternatively, the mold of I in which a surface layer made of a non-porous material having slits is laminated. The main body of the I-viii mold is made of a non-porous material, and a surface layer made of a non-porous material in which through holes or slits are formed via a support material is laminated on the cavity side surface of the main body, and A mold of I in which a void formed between the main body and the surface layer is filled with an intermediate ventilation part made of the porous material, and the main body is provided with a ventilation hole communicating with the intermediate ventilation part. A mold of I, wherein the whole of the I-ix mold is made of a non-ventilating material having ventilation holes, and the ventilation holes made of the porous material are filled in the ventilation holes.

As the porous material, a porous material such as a sintered body or a sprayed body of metal or ceramic powder, or a foamed body of metal or ceramic can be used.

[0011]

In the mold for producing a golf ball of the present invention, the whole or a part of the mold is formed of a porous material having three-dimensional mesh-like fine communication holes as described above. A large number of outlets for discharging to the outside can be provided on the mold cavity surface, so that the air in the cavity can be reliably and smoothly discharged to the outside.

In this case, in particular, the above I-i, I-ii, I
-V and I-vi molds can form innumerable air outlets. In addition, since the surface of a golf ball molded using such a mold is formed into a satin-like shape by the above-mentioned porous material, the step of roughening the surface is omitted or simplified when coating is performed after molding the golf ball. In addition, the adhesion of the coating film to the golf ball is good even without such roughening.

In addition, I-iii, I-iv, I-vi
In the case of the i, I-viii mold, since the surface layer made of a non-porous material having through holes or slits is supported by the porous material, even if a large number of through holes or slits are formed, the The porous material can be surely communicated with the porous material, and therefore a large number of through holes and slits can be formed, and even if such a large number of through holes and slits are formed, there is no risk of weakening the mold.

Further, also in the case of the I-ix mold, a large number of vent holes can be formed, and the hole diameter of the vent holes can be increased, and a large number of vent holes having such a large hole diameter can be formed. However, since the inside is filled with the porous material, the mold is not weakened at all.

Furthermore, when the support pin is made of the above-mentioned porous material, the air in the cavity is discharged not only from the gap between the support pin and the support pin insertion hole but also from the support pin itself. Therefore, the air discharging property is good.

A golf ball molded by using such a mold has a good appearance with no defects such as air entrapment.

[0017]

EXAMPLES Examples of the present invention will now be described with reference to FIGS.
Will be described with reference to. In each figure, the same components as those in FIG. 13 are designated by the same reference numerals, and only the lower mold is shown in each figure.

[Embodiment] FIG. 1 shows the entire lower die 1b formed of a porous material 11 having three-dimensional fine communication holes. Further, FIG. 2 shows that the entire lower mold 1b is made of the porous material 1
However, three kinds of porous materials 11a, 11b, and 11c having different fine pore diameters are used, and the material 11a having the smallest fine pore diameter and the fine pore diameter of the medium are sequentially arranged from the cavity 2 side toward the outer side. The material 11b and the material 11c having the largest micropore diameter are laminated. In addition,
The stacking order of these materials 11a, 11b, 11c is not necessarily limited to this. By thus forming the entire lower die 1b with the porous material 11, it is not necessary to provide a ventilation hole in the lower die 1b.

Here, the porous material is a sintered body obtained by sintering metal powder or ceramic powder so that fine communication holes are three-dimensionally formed, and such metal powder or ceramic powder is sprayed. It can be formed of a porous material such as a thermal spray material, a metal foam, or a ceramic foam obtained by the above. In this case, in the case where the fine communication holes are exposed on the surface of the cavity as shown in 11 of FIG. 1, the diameter of the fine communication holes is 10 μm or less, preferably 5 to 15 μm. There is a risk of defects, and if the pore size is too small, clogging easily occurs. On the other hand, what is indicated by 11a in FIG. 2 is the same as the above, but in the case where the fine communication holes are not exposed on the cavity surface as indicated by 11b and 11c, the hole diameter may exceed 20 μm. Rather, the larger the pore size, the better the air circulation. Therefore, by successively increasing the diameters of the fine communication holes as shown in FIG. 2, air can be discharged more effectively while preventing the occurrence of burrs and the like.

As described above, in the embodiment of FIGS. 1 and 2, the golf ball can be formed in a satin finish by forming the cavity surface with the above-mentioned porous material, so that the surface roughening treatment at the time of coating is omitted. Alternatively, it can be simplified and the adhesion of the coating film is good.

FIG. 3 shows a surface layer made of a non-porous material in which the main body 1b 'of the lower mold 1b is formed of the porous material 11 and a large number of through holes or slits 12 are formed on the surface of the cavity side thereof. 13 is laminated. In this case, an ordinary mold material can be used as the non-porous material, and the size of the through hole or the slit 12 (hole diameter of the through hole, width of the slit) is 100 μm from the viewpoint of preventing burr generation. The following is preferably 40 to 10 μm. In addition, in FIG. 4, in the embodiment of FIG.
A space 15 is interposed between b ′ and the surface layer 13. By forming the space 15 in this manner, the air discharged from the through hole or the slit 12 is diffused in the space 15, The air is discharged to the outside from a wide portion of the porous material 11 of 1b '. Note that FIGS.
Also in this case, it is not necessary to provide a ventilation hole in the lower mold 1b (main body 1b ').

The embodiments of FIGS. 3 and 4 are the same as those of the first and second embodiments.
Unlike the embodiment described above, a golf ball having a substantially smooth surface can be molded, which is advantageous in such a case. Further, when the cavity surface is clogged, it can be more easily cleaned, which is advantageous in maintenance, and by using a strong material such as metal as the non-porous material,
There is also an advantage that it can be easily processed during pin processing or gate processing.

In FIG. 5, the main body 1b 'of the lower mold 1b is formed of a non-porous material having a plurality of ventilation holes 16 and
An example in which the surface layer 13 made of the above-mentioned porous material is laminated on the cavity side surface of the main body is shown in FIG. 6. In the embodiment of FIG. 5, the main body 1b ′ is provided with the surface layer 13 on the support body 14 in the embodiment of FIG.
An example in which the voids 15 are interposed between the main body 1b ′ and the surface layer 13 is shown.

Further, FIG. 7 shows that the main body 1b 'of the lower mold 1b is made of a non-porous material having a plurality of ventilation holes 16 and the intermediate layer made of the porous material is formed on the cavity side surface of the main body. In this example, 17 is formed, and a surface layer 13 made of a non-porous material on which a large number of through holes or slits 12 are formed is formed.

Further, in FIG. 8, the main body 1b 'of the lower mold 1b is formed of a non-porous material, and the through hole or slit 12 is formed on the cavity side surface of the main body 1b' through the support body 14. Surface layer 13 made of porous material
And a space formed between the main body 1b ′ and the surface layer 13 is filled with an intermediate ventilation portion 18 made of the porous material 11 so that the main body 1b ′ communicates with the intermediate ventilation portion. The ventilation holes 16 are provided.

In FIG. 9, the entire lower die 1b is provided with a plurality of ventilation holes 16
And a ventilation part made of the porous material 11 is filled in the ventilation holes 16.

FIG. 10 shows another embodiment of the present invention, in which the support pin 3 is made of the above-mentioned porous material.

In the above-described embodiment, only the lower mold is shown, but the upper mold can be constructed in the same manner as described above, and the multifaceted mold can also have the same construction. The mold can be used for any molding such as injection molding and press vulcanization molding. Depending on the molding method, for example, in the case of injection molding, a support pin is arranged as shown in FIG. You can In this case, when the support pin is provided in the embodiment of FIGS. 1 to 9, the support pin can be formed of the above porous material. Furthermore, the mold is a one-piece,
It can be used for forming both solid golf balls such as two-piece golf balls and wound golf balls, and is particularly suitable for forming covers.

The mold can be used in the same manner as a normal mold, but in this case, the air in the cavity passes through the fine communication holes of the porous material, and as shown in FIG. It is discharged from the exhaust passage 20 of the device 19 to the outside. As shown in FIG. 12, if the mold device 19 is made of the porous material 11, the exhaust passage 20 can be omitted.

When the mold of the present invention is used as a mold for injection molding, air (gas) escapes better in the cavity,
As a result, weld defects and air entry defects are reduced, and low-pressure injection and low-pressure mold clamping are possible. As a result, burrs are reduced, post-processing for removing burrs can be omitted or simplified, defects in this step are eliminated, and factors such as variations in the flight of golf balls due to post-processing are also reduced, and quality is improved. In addition to improvement, post-processing equipment can be reduced. Furthermore, low pressure injection and low pressure mold clamping make it easy to mold a thin cover and reduce the residual stress of the resin (molding material), which reduces ball deformation and improves ball durability. Yes, the life of the mold and molding machine is extended.

When used as a die for press vulcanization of one-piece balls, two-scores and thread-wound center balls, defects due to air inclusion can be eliminated, and defects in the next process and product defects can be reduced. The advantages are that the weight of the charged material can be reduced to eliminate the waste of the molding material, the bumping operation for bleeding air is not required, and the regulation of the shape of the charged material is softened.

Further, by using the mold of the present invention when molding a golf ball cover by a compression molding method,
There are advantages such as elimination of air inflow defects, softening of regulations on the shape of the cover, relaxation of conditions such as mold temperature, reduction of charging weight, and reduction of material waste. .

The lower mold 1b shown in FIGS.
b ', the ventilation holes in FIGS. 5 to 8, the ventilation portion in FIG. 9, and the support pin in FIG. 10 are connected to an air supply device such as a blower, respectively, and pressurized air is released when the upper die is removed after the molding is completed. By sending it toward the cavity, the molded ball can be easily released from the lower mold by the pressure of the pressurized air.

[0034]

According to the present invention, the air in the mold cavity can be surely and smoothly discharged to the outside, so that a defective golf ball is unlikely to occur and a golf ball having a good appearance is surely obtained. It can be manufactured.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a sectional view showing a second embodiment of the present invention.

FIG. 3 is a sectional view showing a third embodiment of the present invention.

FIG. 4 is a sectional view showing a fourth embodiment of the present invention.

FIG. 5 is a sectional view showing a fifth embodiment of the present invention.

FIG. 6 is a sectional view showing a sixth embodiment of the present invention.

FIG. 7 is a sectional view showing a seventh embodiment of the present invention.

FIG. 8 is a sectional view showing an eighth embodiment of the present invention.

FIG. 9 is a sectional view showing a ninth embodiment of the present invention.

FIG. 10 is a sectional view showing a tenth embodiment of the present invention.

FIG. 11 is a sectional view showing an eleventh embodiment of the present invention.

FIG. 12 is a sectional view showing a twelfth embodiment of the present invention.

FIG. 13 is a cross-sectional view showing a conventional injection molding die.

FIG. 14 is a cross-sectional view showing a conventional press vulcanization molding die.

[Explanation of symbols]

 1 Golf Ball Manufacturing Mold 1a Upper Mold 1b Lower Mold 2 Cavity 11 Porous Material 12 Through Hole or Slit 13 Surface Layer 14 Support Body 15 Void 16 Vent 17 Intermediate Layer 18 Middle Vent 19 Mold Device 20 Exhaust Passage

Claims (13)

[Claims] 1. A golf ball mold for forming a hollow spherical cavity therein, wherein the whole or part of the mold is made of a porous material having three-dimensional fine communication holes so that the communication holes communicate with the cavity space. A mold for manufacturing a golf ball, which is formed so as to be possible. 2. The mold according to claim 1, wherein the whole mold is made of the porous material. 3. The mold according to claim 2, wherein a plurality of layers of porous material having fine communication holes having different pore diameters are sequentially laminated from the cavity side toward the outside. 4. A main body of a mold is formed of the above-mentioned porous material, and a surface layer made of a non-porous material in which through holes or slits are formed is laminated on the cavity side surface of the main body made of this porous material. The mold according to claim 1. 5. The mold according to claim 4, wherein a gap is provided between the surface layer made of the non-porous material and the main body made of the porous material with a support body interposed. 6. The mold according to claim 1, wherein the main body of the mold is made of a non-porous material having a plurality of ventilation holes, and the surface layer made of the porous material is laminated on the cavity side surface of the main body. Mold. 7. The mold according to claim 6, wherein a space is provided between the surface layer made of the porous material and the main body made of the non-porous material with a support body interposed. 8. A mold main body is formed of a non-porous material having a plurality of ventilation holes, and an intermediate layer made of the above porous material is laminated on the cavity side surface of the main body, and further on top of that. The mold according to claim 1, wherein a surface layer made of a non-porous material having through holes or slits is laminated. 9. A mold main body is made of a non-porous material, and a surface layer made of a non-porous material having through holes or slits formed on the cavity side surface of the main body is laminated via a support material. The air gap formed between the main body and the surface layer is filled with an intermediate ventilation part made of the porous material, and the main body is provided with a ventilation hole communicating with the intermediate ventilation part. Mold. 10. The mold according to claim 1, wherein the mold is entirely formed of a non-ventilating material having ventilation holes, and the ventilation holes are filled with ventilation parts made of the porous material. 11. A mold for manufacturing a golf ball, wherein a hollow spherical cavity is formed inside and a support pin for supporting a core arranged in the cavity is provided so as to be able to move forward and backward. A mold for producing a golf ball, which is formed of a porous material having fine communication holes. 12. The gold according to any one of claims 1 to 11, wherein the porous material is a porous material selected from a sintered body or a sprayed body of metal or ceramic powder, or a foamed body of metal or ceramic. Type. 13. A method for producing a golf ball by supplying a molding material for a golf ball into a cavity of a mold, wherein the mold according to any one of claims 1 to 12 is used as the mold. Golf ball manufacturing method.