JPH06143349A - Golf ball forming mold - Google Patents

Abstract

PURPOSE:To prevent fin and the like from developing at the central part of each dimple and consequently facilitate the afterworking by a method wherein pins, each of which has the same shape as the shape of the dimple, are arranged at specified positions on the upper and lower parting lines of forming molds and recessed parts, into which the pins are fitted, are formed on the cavity mating surfaces of the upper and lower forming molds. CONSTITUTION:On the inner wall surfaces of an upper mold 1a and of a lower mold 1b, a plurality of projections for forming dimples 4 to be formed on the surface of a golf ball 2 are produced. Further, on the cavity mating surfaces 7 of the upper mold 1a and of the lower mold 1b, the specified number of pins, which have tip shape as the same shape as the shape of each of a plurality of the dimples 5 and each of which spreads over both the molds, are arranged at the specified positions. When the pins 8 are fittingly fixed onto at least one cavity mating surface 7 of those of the upper mold 1a and the lower mold 1b at the working of the cavities of the upper and lower forming molds 1, recessed parts 10, into which the pins are fitted, are formed on the cavity mating surface 7 of the other mold.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for molding a golf ball, and more particularly, it comprises a plurality of dimples located on the upper and lower mold parting lines of the mold for molding, which are arranged on a cavity mating surface. However, the present invention relates to a mold for molding a golf ball in which burrs and the like are eliminated from the center of the dimples existing on the parting line to facilitate post-processing.

[0002]

2. Description of the Related Art Generally, it is said that the dimple arrangement formed on the spherical surface of a golf ball has excellent symmetry, and the higher the symmetry, the better the flight distance of the golf ball. By the way, the conventional golf balls are arranged so that the dimples have symmetry about a large number of lines of symmetry, based on spherical division based on a regular dodecahedron, regular icosahedron, 12-20 octahedron, or the like. However, the dimples are not arranged on a great circle (parting line) which is used as a mold dividing line (a seam of the mold) and divides the spherical surface into two parts. For this reason, it is usual that no dimples are arranged on the great circle in molding a golf ball when using a mold for splitting into two parts.

On the other hand, a golf ball in which dimples are arranged on the great circle in order to improve the symmetry is also disclosed (Japanese Patent Laid-Open Nos. 64-8983, 3-286786 and 3-286786). 3-140168).

[0004]

By the way, in the conventional golf ball in which the dimples are not arranged on the great circle described above, there is a limit to the number of lines of symmetry, which results in the symmetry of the golf ball. There is a limit to improving the property, and arranging the dimples on the mold parting line to manufacture a molding die does not allow accurate processing of the radial dimples or alignment processing of the upper and lower molds. It was very difficult.

Further, there has been proposed a method of forming a dimple on a parting line by cutting or heat working after molding a golf ball. However, in the case of the method for forming dimples by the method as described above, burrs and the like are severely generated at the center of the dimples existing on the parting line, and the burrs and the like are removed by conventional centerless polishing for golf balls. However, there was a problem that post-processing was difficult.

Therefore, as a mold for forming dimples on a great circle that divides a spherical surface into two, for example, Japanese Patent Publication No. 3-813.
No. 94 has a corrugated surface that is closely attached to each other and extends along the equator around the equator, and the inner surfaces of both dies are located on the equator and at positions that do not intersect the split surface. There is proposed a method in which a projection for dimple formation is formed. However, manufacturing such a complicated mold requires a lot of labor and time, and also requires a great deal of cost. In addition, there are many restrictions on the dimple arrangement surface.

The present invention has been devised in view of the above-mentioned conventional problems, and when molding a golf ball having dimples extending over a symmetry axis including a great circle dividing a spherical surface into two, To provide a mold for molding a golf ball, which has no burrs at the center of the dimples, which makes it easy to post-process the golf ball and which can be easily removed by conventional coreless polishing for golf balls. That is the purpose.

[0008]

In order to achieve the above object, the present invention provides a tip shape having the same shape as the shape of a plurality of dimples extending over the dividing line on the upper and lower dividing lines of the molding die. The gist of the present invention is to dispose a predetermined number of the provided pins at a predetermined position and to form a recess into which the pins fit in the cavity mating surfaces of the upper and lower molding dies.

[0009] Further, one of the cavity mating surfaces of the upper and lower molding dies is provided with a recess in which the pin is fixed and the other die is fitted with the pin, or the cavity mating surfaces of the upper and lower molding dies are It is also possible to take in and out a predetermined number of pins and to make them movable in the mold dividing direction.

[0010]

The present invention is configured as described above, and a tip shape having the same shape as the shape of a plurality of dimples extending in advance on the dividing line is formed on the cavity mating surface on the upper and lower dividing lines of the molding die. When a golf ball is molded with a certain number of pins provided at a predetermined position and the upper and lower molding dies are closed, the golf ball is molded across the symmetrical axis including the parting line as in the conventional case. No burr is generated at the center of the dimples to be formed, post-processing is easy, and the dimples can be easily removed by conventional centerless polishing for golf balls.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a front view of a golf ball 2 molded using the upper and lower molding dies 1 according to the present invention,
FIG. 2 is a partially cutaway perspective view of an upper and lower molding die 1 including an upper die 1a and a lower die 1b. 3 is a dividing line (parting line) and 4 is formed on the surface of the golf ball 2. Dimples 5 indicate dimples extending over the dividing line 3.

A plurality of projections 6 for molding the dimples 4 formed on the surface of the golf ball 2 are formed on the inner wall surfaces of the upper mold 1a and the lower mold 1b. In the cavity mating surface 7 of the upper mold 1a and the lower mold 1b of the upper and lower molding dies 1 in the embodiment of the present invention, as shown in FIGS. 5 dimples
Pin 8 having a tip shape having the same shape as
A predetermined number is arranged at a predetermined position.

When the pin 8 is inserted and fixed to at least one cavity mating surface 7 of the upper die 1a and the lower die 1b when the cavity 9 of the upper and lower molding die 1 is processed,
The cavity mating surface 7 of the other mold has a recess 10 into which the pin 8 is fitted. As a general rule, the cavity mating surface 7 of the upper mold 1a and the lower mold 1b which face each other
In this case, only the semi-process of the recess 10 corresponding to the pin 8 is performed.
Further, the plurality of pins 8 can also be configured to be capable of advancing and retracting or moving up and down with respect to the cavity mating surface 7 of the upper mold 1a and the lower mold 1b.

As described above, the upper mold 1 of the upper and lower molding dies 1
When a predetermined number of pins 8 are disposed at predetermined positions on the cavity mating surface 7 of the a and the lower mold 1b, and the golf ball 2 is molded using the upper and lower molding dies 1, the dividing line 3 No burr or the like is generated in the central portion of the dimple 5 formed over the upper portion, and therefore, when the formed golf ball 2 is processed, the dimple formed over the dividing line 3 is formed. The central part of No. 5 does not need to be processed at all and is easy to be post-processed. Moreover, burr and the like can be easily removed by the conventional centerless polishing for golf balls as well as around the current support pins and air vent pins. It is something that can be done.

[0015]

As described above, according to the present invention, a tip shape having the same shape as the shape of a plurality of dimples extending over the dividing line is provided on the cavity mating surface on the dividing line of the upper and lower molding dies. Since the pin is arranged in a predetermined number at a predetermined position and the recess for fitting the pin is formed in the cavity mating surface of the upper and lower molding dies, burrs or the like are formed at the center of the dimple straddling the dividing line. Since it does not occur, it is easy to post-process the golf ball, and burrs and the like can be easily removed by the conventional centerless polishing for golf balls as well as around the current support pins and air vent pins. This has the effect of improving workability and productivity.

[Brief description of drawings]

FIG. 1 is a front view of a golf ball molded by using the upper and lower molding dies according to the present invention.

FIG. 2 is a partially cutaway perspective view of the upper and lower molding dies.

FIG. 3 is a perspective view of a pin arranged in a cavity land portion of a vertical molding die.

[Explanation of symbols]

1 Upper and Lower Molds 1a Upper Mold 1b Lower Mold 2 Golf Ball 3 Dividing Line (Parting Line) 4 Dimples 5 Dimples Straddling Dividing Lines 6 Protrusions 7 Cavity Matching Surface 8 Pins 9 Cavities 10 Recesses

Claims (3)

[Claims] 1. A golf ball molding die having dimples on the upper and lower mold parting lines of a molding mold, wherein a plurality of dimples straddling the dividing line are formed on the upper and lower parting lines of the molding mold. A pin having a tip shape having the same shape as the shape is arranged in a predetermined number at a predetermined position, and a recess for fitting the pin is formed in the cavity mating surface of the upper and lower molding dies. Mold for golf ball molding. 2. The golf ball molding die according to claim 1, wherein one of the cavity molding surfaces of the upper and lower molding dies is provided with a recess for fixing the pin and the other die is fitted with the pin. Type. 3. The cavity mating surfaces of the upper and lower molding dies,
The golf ball molding die according to claim 1, wherein a predetermined number of pins can be taken in and out and movable in a die dividing direction.