JP3005066B2 - Golf ball - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a golf ball, and more particularly, to a golf ball having a reduced shot feeling without substantially reducing the flight distance.

[0002]

2. Description of the Related Art Conventionally, various golf balls have been provided, but the golfer's most desired golf ball is first the flight distance and secondly the shot feeling. That is, the golfer wants a golf ball that can fly as much as one yard and has a light feel at impact. In order to meet the demands of the golfer, a golf ball is designed, and the mass of the golf ball, the shape of the dimple, the total number, and the like are selected.

By the way, the mass of a golf ball is USG
According to the standard of A, the weight is set to 45.92 g or less.
The specification of the mass is only the upper limit of 45.92 g, and there is no specification of the lower limit. Therefore, as long as the ball does not exceed 45.92 g, it can be said that even a light ball is a golf ball conforming to the standard.

However, most golf balls currently on the market are made as heavy as possible without exceeding the upper limit of 45.92 g, and are usually set in the range of 45.0 g to 45.9 g. I have. This is because a lighter golf ball loses inertia during flight and stalls in the latter half of the trajectory, resulting in a shorter flight distance.

[0005] The weight of the floating ball for the water practice area is reduced to 40.0 g or less, in order to satisfy the essential requirement of floating on the water. It is lower than the ball. The floating ball is made from the viewpoint that the flight distance cannot be reduced due to weight reduction.

As described above, the conventional golf ball, except for the floating ball described above, is made as heavy as possible within a range not exceeding 45.92 g to prevent stall in the latter half of the trajectory and to fly even a little. It is manufactured in.

[0007]

However, the hitting sensation, which is an important property of a golf ball along with the above-mentioned flight distance, has been variously studied in view of the structure and composition of the golf ball. Thus, a golf ball with a sufficiently light feel at impact has not been obtained.

A golf ball can reduce the feel of a ball by reducing its mass. However, if the weight is reduced, as described above, the golf ball loses inertia during flight and stalls in the latter half of the trajectory. There is a problem that the distance is reduced.

As described above, when trying to obtain a light feel at impact by reducing the weight, a disadvantage arises in that the flight distance is reduced. Conversely, when the mass is increased in order to increase the flight distance, a disadvantage arises in which the feel at impact is increased, and the flight distance is increased. Good characteristics could not be obtained with a conventional golf ball in both the hitting feel and the feel at impact.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the conventional golf ball, and has a lightening of the mass of the golf ball to sufficiently reduce the feel at impact and a flight distance caused by the weight reduction. The object of the present invention is to provide a golf ball having a sufficiently light hit feeling without reducing the flight distance by compensating for the decrease in the golf ball surface by increasing the dimple area having a lift increasing effect provided on the golf ball surface. is there.

[0011]

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to a golf ball having dimples on its surface and having a mass of 4
It is lightweight from 1.0 g to 44.5 g, and the ratio of the sum of the dimple areas to the surface area of the virtual sphere of the golf ball is 7
0% or more, the impact force when hit by a golf club driver at a head speed of 48.8 m / sec is as small as 1250 kgf to 1360 kgf, and the flight distance is reduced while being lightweight and light in shot feeling. It is intended to provide a golf ball characterized by being suppressed.

The above-mentioned virtual sphere of a golf ball refers to a sphere assuming that there is no dimple on the spherical surface of the golf ball, and the dimple area refers to the area of a virtual plane surrounded by the outer edge of the dimple.

The arrangement of the dimples provided on the surface of the golf ball can be any arrangement including an octahedral arrangement, and the arrangement method is not limited. The total number of dimples arranged on the golf ball surface is 280 to 5
If the sum of the areas of all the dimples is equal to or more than 70% of the surface area of the virtual sphere of the golf ball in the range of 40 as described above, the total number of dimples can be appropriately selected in the above range.
Also, usually, the dimple diameter is 2.5mm ~ 4.5mm,
Although the depth is in the range of 0.1 mm to 0.2 mm, the diameter and the depth of each dimple are arbitrarily selected as long as the dimple surface occupancy is 70% or more as in the case of the total number of dimples.

The mass of the golf ball is 41.0 g to 4
The range of 4.5 g is set based on experimental data. If the weight exceeds 44.5 g, the effect of lowering the impact force when hitting a golf ball with a club is not sufficient, and the feel at impact is not reduced. If the weight is less than 41.0 g, the decrease in the flight distance cannot be suppressed even if the surface area of the dimple is increased.

The dimple surface area occupancy is 70%.
The reason for setting the percentage to at least 70% is that if it is less than 70%, the dimple effect of generating lift cannot be sufficiently promoted, and the stall of the golf ball in the latter half of the trajectory cannot be suppressed. Note that the surface area occupancy is more preferably 77% or more.

[0016]

The golf ball according to the present invention having the above-described structure has a mass set in the range of 41.0 g to 44.5 g,
Since the golf ball is lighter than a conventional golf ball, the impact force when hit with a golf club is small, and a light shot feeling that cannot be obtained with a conventional golf ball can be obtained.

Further, in the present invention, since the surface area occupation ratio of the dimples is set to 70% or more and the wider range of the spherical surface of the golf ball is covered with the dimples, the original effect of the dimples of the generation of lift can be promoted. The stall in the latter half of the trajectory caused by the reduced weight of the golf ball can be suppressed. As described above, it is possible to obtain a golf ball that satisfies both the flight distance and the shot feeling while minimizing the decrease in the flight distance due to the reduction in mass.

[0018]

Next, the present invention will be described in detail based on an embodiment shown in the drawings. The golf ball according to the first embodiment of the present invention, which is shown in FIG. 1 and whose specifications are shown in Table 1 below, has a mass of 44.5 g and a diameter (outer diameter) D of 42.70 ± 0.2.
03 mm. The spherical surface 1 of the golf ball is provided with 336 dimples 2 in an octahedral arrangement. The golf ball has a one-piece structure using butadiene rubber as a base rubber, and has a compression of 90 ± 2.

[0019]

[Table 1]

As shown in FIG. 2, the dimples 2 are all of the same shape, have an arcuate cross section, and have a diameter (dimple diameter d) of 3.9 mm of a perfect circle composed of an imaginary plane 4 surrounded by an outer edge 3. Therefore, the area of the virtual plane 4 (dimple area) is set to 11.95 mm ² .

In the first embodiment, the dimple area and dimple 2
Is set as described above, the ratio (surface area occupancy) of the sum of the dimple areas to the surface area of the sphere (golf ball virtual sphere) assuming that there are no dimples 2 on the spherical surface 1 of the golf ball is It is set to 70.2%.

Specifically, the surface area occupancy is calculated as follows. First, the sum of the dimple areas is obtained by (dimple area) × (total number of dimples), and is (3.9 / 2) ² · π = 3.8025π (mm ² ). Since the total number of dimples is 336,
The sum total of the dimple areas is 3.8025π × 336 = 1277.6π (mm ² ). On the other hand, the surface area of the virtual sphere of the golf ball can be obtained by calculating the surface area of a sphere having an outer diameter equal to the outer diameter of the golf ball, so that 4 × π × (42.67 / 2) ² = 1820.7π (mm ² ) Becomes Therefore, the surface area occupation ratio is (1277.6π / 1820.7π) × 100 = 70.2.
(%).

As shown in Table 1 above, the golf ball of the second embodiment has the same dimple diameter and surface area occupancy as those of the first embodiment. It is set lighter than the example. The increase or decrease in the mass is adjusted by increasing or decreasing the amount of the filler.

As shown in Table 1, the golf balls of the third and fourth embodiments have a dimple diameter of 4.1 mm and a surface area occupancy of 77.5%. The golf ball of the third embodiment weighs 44.5 g, which is the same as that of the first embodiment.
On the other hand, the mass of the golf ball of the fourth embodiment is set to 41.5 g, which is the same as that of the second embodiment. in this way,
In the first and third embodiments, the mass is 44.5 g, while in the second and fourth embodiments, the mass is 41.5 g.

The golf balls of the second to fourth embodiments have a one-piece structure using butadiene rubber as a base rubber and have an outer diameter D of 4 as in the first embodiment.
2.70 ± 0.03mm, compression is unified to 90 ± 2. The arrangement and total number of the dimples are set the same as in the first embodiment.

As described above, in the golf ball according to the present invention, the mass is set in the range of 41.0 g to 44.5 g, and the conventional golf ball (usually 45.0 g to 45.9 g) is used.
The weight is set lighter than g). Due to the weight reduction, in the golf ball according to the present invention, the impact force at the time of hitting is reduced, so that a light feel at impact can be obtained.

It is preferable that the impact force defining the feel at impact is in the range of 1250 kgf to 1360 kgf under the following conditions. That is, a driver 1 equipped with a Persimmon head having a head weight of 210 g and a loft angle of 9 ° as a club, and a shaft having a length of 43 inches and a hardness of X
Using a turn, hit the sweet spot at a head speed of 48.8 m / sec. The value of the impact force is the acceleration 439 manufactured by Buell Kea Co. on the back side of the head.
Attach 3 and read the peak value with the oscilloscope,
The peak value was multiplied by the head weight and measured. In the measurement under the conditions, by setting the impact force within the above range, it is possible to obtain an appropriate light hitting feeling.
If it is less than 1250 Kgf, the shot feeling becomes too light, and if it exceeds 1360 Kgf, the shot feeling becomes the same as the conventional one, and it becomes impossible to obtain a light shot feeling.

[0028]

EXPERIMENTAL EXAMPLE An experiment was conducted to confirm the characteristics of the golf ball according to the present invention. First, in order to compare with the golf balls of the first to fourth embodiments, golf balls of first to sixth comparative examples having the specifications shown in Table 1 above were prepared.

As in the first to fourth embodiments, the golf balls of the first to sixth comparative examples have 336 dimples of the same shape having a circular arc cross section as shown in FIG. It is a golf ball having a face arrangement, and the material and structure are unified with the above embodiment, and the outer diameter and the compression are also unified with the above embodiment. Therefore, the first comparative example
The sixth comparative example differs from the first to fourth examples only in the dimple diameter (accordingly, the surface area occupancy) and / or the mass of the golf ball.

The golf ball of the first comparative example is a golf ball having a dimple diameter of 3.7 mm, a surface area occupancy of 63.2%, and a mass of 45.9 g. The golf ball of the first comparative example is
It is a golf ball conventionally marketed by the present applicant under the trade name "DUNLOP RANGER" and is one of the golf balls having the largest share of golf balls in the world.

The golf balls of the second and third comparative examples have a dimple diameter of 3.7 mm, a surface area occupancy of 63.2%, and a mass of 44.5, respectively, as in the first comparative example.
g, 41.5 g, and 39.0 g. That is, in the second comparative example and the third comparative example, the dimple diameter and the surface area occupancy are kept the same as those of the golf ball of the first comparative example.
The mass is set to be the same as in the first and third embodiments, and the second and fourth embodiments.

In the fourth comparative example, similarly to the second and third comparative examples, the mass was set to 39.0 g while the dimple diameter and the surface area occupancy were kept the same as in the first comparative example. It is set lighter than in the second and fourth embodiments. The fifth comparative example and the sixth comparative example have a mass of 3 as in the fourth comparative example.
The dimple diameter and the surface area occupancy are set equal to those of the first and second embodiments, and the third and fourth embodiments, respectively. That is, in the fifth comparative example, the dimple diameter is set to 3.9 mm and the surface area occupation ratio is set to 70.2%, while in the sixth comparative example, the dimple diameter is set to 4.1 mm and the surface area occupation ratio is set to 77.5%.

The golf balls of the first to fourth embodiments and the first to sixth comparative examples were selected by using a swing robot manufactured by Tsurutemper, and the club was selected by a driver (W1). A flight distance test was performed under the conditions of a head speed of 48.8 m / s. Spin is 3500 ± 30
The machine conditions were adjusted so that 0 rpm and the ball launch angle were 9.0 ± 0.5 °. The flight distance is the distance from the ball launch point to the ball rest point.

At the same time, an accelerometer was attached to the driver, and the impact force at the time of impact was measured in the form of a speed change of a club (driver). The measurement of the impact force is a general method for evaluating the feel at impact of a golf ball. That is, it can be said that a golf ball having a higher impact force has a higher hitting feeling, and a golf ball having a lower impact force has a lighter hitting feeling.

The test results, that is, the flight distance, impact force and shot feeling are as shown in Table 1 above, and the average of the results of experiments on 20 golf balls for each of the examples and comparative examples. The hitting feeling was such that a top amateur having an average score of about 75 per round actually hit the golf balls according to the examples and the comparative examples, and the hitting feeling was “heavy”, “light”, and “extremely light”. Are shown in three stages.

FIG. 3 shows the relationship between the mass and the impact force shown in Table 1. From FIG. 3, it was confirmed that the mass of the golf ball and the impact force at the time of hitting were almost directly proportional. That is, while the impact force of the first comparative example having a mass of 45.9 g, which is a conventional golf ball, is 1423 kgf, the first embodiment having a mass of 44.5 g has 1350 kgf, and the third embodiment has 1351 kgf.
Kgf, mass of 41.5 g, 1286 in second and fourth embodiments
Kgf. As described above, the golf ball of the present embodiment was able to reduce the impact force by about 5% to 10% compared to the conventional golf ball.

As described above, the golf balls of the first to fourth embodiments according to the present invention have an impact force of 1 under the same conditions as those described above that define the preferable range of the impact force.
It was in the range of 286 Kgf to 1350 Kgf, which was within the above preferred range of 1250 Kgf to 1360 Kgf.

In the test for feel at impact, the first comparative example having a large mass in the related art has a heavy feel, whereas the first comparative example has a heavy feel.
In the first to fourth examples in which the weight of the golf ball of the comparative example was reduced, the result was that the shot feeling was "light". From the above, it was confirmed that the golf ball according to the present invention can reduce the feel at impact as compared with a conventional golf ball.

Further, from the straight line A showing the tendency of the plotted points of the experimental results of the first to fourth examples and the first to sixth comparative examples in FIG. 3, if the mass exceeds 44.5 g, It was confirmed that the drop in impact force was small and the shot feeling was not too light. According to the results, in the present invention, the mass of the golf ball is set to a range not exceeding 44.5 g.

FIG. 4 shows the relationship between the surface area occupancy and the flight distance in Table 1. As shown in FIG. 4, when the mass was the same, it was confirmed that the greater the surface area occupancy, the longer the flight distance. That is, a first comparative example which is a conventional golf ball
In the (surface area occupancy rate of 63.2%), the flight distance is 243 yards, but in the first to fourth embodiments in which the surface area occupancy rate is set to 70.2% or 77.5%, the mass is 44.5 g. Or 4
Despite being reduced to 1.5 g, a flight distance of 243 to 239 yards was obtained, and a decrease in the flight distance was suppressed to a maximum of 4 yards, confirming that a sufficient flight distance could be secured.

In FIG. 4, a broken line I connecting the flight distances of a golf ball having a mass of 44.5 g (first embodiment, third embodiment, and second comparative example) and a golf ball having a mass of 41.5 g 2
When the surface area occupancy is less than 70% from the polygonal line II connecting the flight distances of the examples, the fourth example, and the third comparative example, the flying distance is smaller than that of a commercially available golf ball (first comparative example). It was confirmed that the height dropped to 4 yards or more. Further, it was confirmed from the above two polygonal lines I and II that when the surface area occupancy exceeds 77%, the decrease in the flight distance can be further suppressed.

FIG. 4 shows that a golf ball weighing 39.0 g (fourth comparative example, fifth comparative example, and sixth comparative example) has a polygonal line III connecting the flight distances. Even when the surface area occupancy was 70% or more, it was confirmed that the flight distance was greatly reduced as compared with the conventional golf ball. Therefore, considering the line graphs I and II together, if the mass is less than 40 g, the flying distance due to the reduced mass is increased even if the surface area occupancy is increased to 70% or more to promote the lift effect of the dimple. It was confirmed that the decrease could not be compensated. Therefore, the mass of the golf ball of the present invention is 41.0 g or more.

[0043]

As is clear from the above description, in the golf ball according to the present invention, since the mass is set in the range of 41.0 g to 44.5 g, which is lighter than the conventional golf ball, the golf ball is hit with a club. The impact force at the time is small, and the shot feeling can be lightened. In addition, the decrease in the flight distance due to the decrease in the mass is compensated for by setting the ratio of the sum of the dimple areas to the surface area of the virtual sphere of the golf ball to 70% or more to promote the effect of generating the lift of the dimples. . Therefore, a stall in the latter half of the trajectory can be prevented, and a decrease in flight distance due to weight reduction can be suppressed, and a sufficient flight distance can be secured. That is, the golf ball according to the present invention can lighten the shot feeling while suppressing a decrease in the flight distance, and has good characteristics in both the flight distance and the shot feeling.

[Brief description of the drawings]

FIG. 1 is a front view showing a first embodiment of a golf ball according to the present invention.

FIG. 2 is a partially enlarged sectional view of FIG.

FIG. 3 is a diagram illustrating a relationship between a mass of a golf ball and an impact force.

FIG. 4 is a diagram showing a relationship between a surface area occupancy and a flight distance.

[Explanation of symbols]

 Reference Signs List 1 spherical surface 2 dimple 3 outer edge 4 virtual plane d dimple diameter D golf ball outer diameter

Claims (4)

(57) [Claims] 1. A golf ball having dimples on its surface, having a light weight of 41.0 g to 44.5 g, a ratio of the total dimple area to the surface area of the golf ball virtual sphere being as large as 70% or more, Golf club driver with head speed of 48.8
The impact force when hit at m / sec is 1250
A golf ball characterized by being small in weight from kgf to 1360 kgf, light in weight and light in feel at impact, while suppressing a decrease in flight distance. 2. The golf ball according to claim 1, wherein a ratio of a sum of dimple areas to a surface area of the virtual sphere of the golf ball is 77% or more. 3. The total number of the dimples is from 280 to 5
The golf ball according to claim 1, wherein the number of the golf balls is forty. 4. The dimple has a diameter of 2.5 mm to 4.5 mm and a depth of 0.1 mm.
The golf ball according to any one of claims 1 to 3, wherein the golf ball has a diameter of 0.2 mm to 0.2 mm.