JP4166777B2 - Golf ball - Google Patents

Description

  The present invention relates to a golf ball, and more specifically, to a golf ball having an improved dimple pattern.

  A golf ball generally has a plurality of dimples formed on a spherical outer surface. Conventional dimples are circular depressions that reduce drag and increase lift. These dimples are inclined from the outer surface to form a recess.

  The drag is an air resistance facing the flight direction of the golf ball. As the ball moves through the atmosphere, the velocity of the air surrounding the ball is different and thus the pressure is different. Air exerts maximum pressure at the residence point on the front of the ball. For this reason, air flows over the surface of the ball, increasing its velocity and decreasing its pressure. At some separation point, the air leaves the ball surface and creates a large turbulent region behind the ball. This turbulent region is called a wake and has a reduced pressure. The ball decelerates due to the difference between the high pressure at the front of the ball and the low pressure behind the ball. This is the main source of drag against the ball.

  The golf ball dimples cause a thin boundary layer of air adjacent to the outer surface of the ball to flow in a turbulent manner. For this reason, this thin boundary layer is called a turbulent boundary layer. The turbulence energizes the boundary layer and acts to shift the separation point backwards so that this layer further contacts the outer surface of the ball. As a result, the wake area is reduced, the pressure behind the ball is increased, and the drag is substantially reduced. It is around each dimple that the dimple wall tilts from the outer surface of the ball, which actually forms a turbulent boundary layer.

  Lift is the upward force acting on the ball and is formed by the difference in pressure between the top of the ball and the bottom of the ball. This pressure difference is formed by the curvature of the air flow due to the backspin of the ball. By backspin, the top of the ball moves with the air flow, further delaying the air separation point backwards. Conversely, the bottom of the ball moves in the opposite direction of the air flow and shifts the separation point forward. Since the separation points are asymmetric in this way, the flow pattern is arched and the air flowing over the top of the ball moves faster than the air flowing under the bottom of the ball. As a result, the air above the ball is at a lower pressure than the air below the ball. This pressure difference generates an overall force, which is called lift and causes the ball to act upward. The circumference of each dimple is also important in optimizing this flow phenomenon.

  Almost all golf ball manufacturers increase golf ball flight distance by reducing drag and increasing lift with dimples. In order to improve the performance of the ball, it is preferable to provide a large number of dimples. Therefore, a large number of dimples are provided around the ball and are uniformly distributed on the outer periphery of the ball. When placing dimples, an attempt is made to minimize the space between the dimples. This is because such a space does not improve the aerodynamic characteristics of the ball. From a practical point of view, typically dimensioned circular dimples with diameters in the range of about 0.100 inches to about 0.180 inches correspond to 300 to 500.

  Theoretically, when a large number of small dimples are employed, the outer periphery of the dimples as a whole becomes larger and the aerodynamic characteristics are improved when compared with dimples having a normal size. However, in practice, even if the dimples are reduced, the drag may not be efficiently suppressed to increase the lift. This is because, in part, small dimples tend to fill up with paint. A paint flood occurs when the paint coat on the golf ball surface fills the small dimples, thereby reducing the aerodynamic effectiveness of the dimples. On the other hand, a small number of large dimples is inefficient. This is because the circumference of one large dimple is smaller than the circumference of a group of small dimples.

  Other attempts to maximize the dimple region include polyhedral surfaces, i.e., a plurality of planes, as proposed in many patent documents including Patent Document 1, Patent Document 2, Patent Document 3, Patent Document 4, and Patent Document 5. A polygonal dimple having a dimple surface composed of a surface is used. Theoretically, a wider dimple region is obtained by these polygonal dimples. As shown in FIGS. 1 and 2, the land area between the polygonal dimples typically has a uniform width across the entire ball surface. If the width of the land area becomes narrow, the dimple area increases.

As a result, there remains a need in the technical field of golf balls to fine tune the flight distance upon impact of a golf ball without sacrificing other desired properties of the golf ball.
US Pat. No. 6,290,615 US Pat. No. 5,338,039 US Pat. No. 5,174,578 U.S. Pat. No. 4,830,378 U.S. Pat.No. 4,090,716

  The present invention has been made in consideration of the above-described circumstances, and an object thereof is to provide a golf ball capable of finely adjusting the flight distance of the golf ball without sacrificing other characteristics.

  According to this invention, in order to achieve the above-mentioned object, the configuration as described in the claims is adopted.

  The present invention will be further described.

  The present invention is directed to a golf ball in which a plurality of dimples are formed on a substantially spherical land. According to one aspect of the present invention, the plurality of dimples include polygonal portions, and are arranged on the spherical surface so that the sides of the adjacent polygonal portions are substantially parallel. The dimple pattern defines a first width between the first dimple and the second dimple adjacent thereto, and a second width between the first dimple and the third dimple adjacent thereto. . These widths are constant between any two dimples, but the first width and the second width are different.

  These and other features of the invention are as set forth in the claims and will be described in detail below.

  According to the present invention, the flight distance of the golf ball can be finely adjusted without sacrificing other characteristics.

  When polygon dimples are employed and the surface of the lands that separate the polygon dimples, that is, the surface of the non-dimple, approaches a thin line, the surface area of the land approaches zero. By bringing the land surface closer to zero and employing a highly resilient material for the core / cover material, the golf ball exceeds the currently available flight distance and overall performance level.

  The distance that the golf ball flies upon impact depends on the ball's coefficient of restitution (COR) and aerodynamic characteristics. COR is the ratio of the relative velocity after a collision to the relative velocity between the two objects before the direct collision of the two objects. As a result, COR takes a value from 0 to 1. 1 corresponds to complete elastic collision, and zero corresponds to complete inelastic collision. For golf balls, COR has been approximated by the ratio of the speed of the golf ball after impact to the speed of the golf ball before impact.

  COR is an important measure for the collision between a ball and a large substance. One conventional technique for measuring COR uses a golf ball or golf ball component, an air cannon, and a stationary steel plate. The steel sheet forms an impact surface weighing about 100 pounds or about 45 kg. A pair of ballistic light screens are spaced apart between the air cannon and the steel plate to speed up the ball. The ball is fired from the air cannon toward the steel plate over a range from 50 ft / s (15.2 m / s), which is a test speed, to 180 ft / s (54.9 m / s). Unless otherwise stated, the COR data presented in this application was measured using a speed of 125 ft / s (38.1 m / s). While the ball is facing the steel plate, the ball activates each light screen and the time on each light screen is measured. In this measurement, the incident time interval is proportional to the incident speed of the ball. The ball hits the steel plate, reflects and passes through the light screen. This again measures the time interval required to travel between the light screens. For this reason, the time interval at the time of reflection is proportional to the ball speed at the time of reflection. For COR, the coefficient of restitution can be calculated as the ratio of the reflection time interval to the incident time interval.

  The COR of a golf ball is affected by many factors, including the core composition and the cover composition. The core may be a single-layer core or a multi-layer core. The core may be solid or liquid filled. Further, it may be a bobbin or foam, or may contain a filler. The cover may be a single layer cover or a multi-layer cover. The cover may be thin or thick. The cover controls spin and feeling as high or low hardness. The cover may be a thermoplastic material, a thermosetting material, or both. The composition and dimensions of the cover and core are described in detail in US Pat. Nos. 6,419,535, 6,152,834, 5,919,100, 5,858,172, 5,783,293, 5,692,974, PCT Publications WO 00/29129 and 00/23519. Please refer to these. All the above factors affect the COR of the ball.

  The golf ball preferably has a core and a cover. The core is one or more layers, and the cover is also one or more layers. The inner cover layer or outer cover layer comprises polyurethane, polyurea, polyurethane ionomer, partially or fully neutralized ionomer, metallocene catalyst polymer, or blends thereof. Preferably, the thickness of the outer cover layer is between about 0.015 inches and about 0.060 inches and the thickness of the inner cover layer is between about 0.015 inches and about 0.060 inches. Also, the hardness of the outer cover layer is preferably about 10 to about 70 Shore D hardness, and the hardness of the inner cover layer is about 40 to about 90 Shore D hardness. Also preferably, the PGA compression of the ball ranges from about 30 to about 100 m.

  Hardness is preferably measured on the Shore D scale in the form of buttons or slabs according to ASTM D-2240. More specifically, the Shore D scale measures the dent hardness of the polymer. A larger Shore D indicates that the polymer has a higher hardness.

A spring load force is applied to the golf ball center, golf ball core, or golf ball to be measured, and compression is measured using a manual device (“Atti gauge”) manufactured by Atti Engineering Company. The instrument is equipped with a Federal Dial Gauge Model D81-C and uses a calibration spring under a known load. The surface to be inspected is subjected to a force of a distance of 0.2 inches (5 mm) against this spring. If the spring is compressed by 0.2 inches, the compression is evaluated as 100, and if the spring is compressed by 0.1 inches, the compression value is evaluated as zero. To explain more clearly, a soft material has a smaller Atti gauge (measure) than a material that is hard and hard to shrink. The compression measured with this device is also called PGA compression. The approximate relationship between Atti compression or PGA compression and Riehle compression can be expressed as:
(Atti compression or PGA compression) = (160-Riehl compression)

  According to one aspect of the present invention, the distance that the ball flies is adjusted little by little without affecting the other characteristics of the ball using the modified dimple pattern. FIG. 3 shows the ball as a whole. Here, the same number represents the same part. Reference numeral 10 indicates a golf ball 10 having a spherical surface as a whole. The spherical surface is defined by a point on the 1.68 inch diameter of the golf ball 10 for USGA official golf balls. For informal balls, the spherical surface can be thought of as an inner sphere covered by an outer surface, as described in US Pat. No. 6,290,615. As for the spherical surface, either concept may be applied to the present invention.

  A plurality of dimples 12 are formed on the outer surface of the golf ball 10, and are separated by an outer non-dimple surface, that is, a land surface, generally indicated by 13. As shown, the dimple 12 is a triangle. The dimples suitable for use in the present invention include dimples of any shape, such as triangles, squares, rectangles, pentagons, hexagons, heptagons, octagons, other polygons, circles, hemispheres , Ellipses, and any other shape. Preferably, a polygonal dimple 12 is selected, and the resulting dimple pattern may or may not include a circular dimple. The present invention is not limited to any dimple shape described herein.

  Preferably, the dimple 12 is a recess extending into the golf ball 10. Alternatively, the dimple 12 may be a convex portion that extends beyond the spherical surface of the golf ball 10.

  The dimple pattern is arranged in a recognizable region (section or region) that forms an overall pattern on the surface of the golf ball 10. Preferably, the dimples 12 are arranged in an icosahedron as a whole, that is, in 20 recognizable triangular regions. Other suitable patterns include tetrahedron, octahedron, hexahedron, dodecahedron, other polyhedrons, or groupings of dimples that can be magnetically separated.

  Here, “inter-dimple space” means the width of the land region 13 between any two adjacent dimples 12. Preferably, the inter-dimple space between any two adjacent polygonal dimples is constant. In other words, the sides of adjacent polygonal dimples are substantially parallel and the space between them is constant. For example, the spaces 20 and 22 shown in FIG. 3 are constant. The space between the dimples may be a circular or other non-polygonal structure, such as the space 24. A set of inter-dimple spaces forms a land region 13. Preferably, the surface area of the land region 13 is about 40% or less of the total surface area of the spherical surface of the golf ball 10. More preferably, less than about 30% of the total surface area of the golf ball 10 is the land area. More preferably, less than about 20% of the total surface area of the golf ball 10 is the land area.

  As shown in the embodiment of FIG. 3, the dimples 12 are triangular depressions separated by a relatively narrow inter-dimple space 22 or a relatively thick inter-dimple space 20. Preferably, the width of the inter-dimple spaces 20, 22 is in the range of 0.001 to 0.030 inches. More preferably, the width of the inter-dimple spaces 20, 22 is in the range of 0.003 to 0.025 inches. More preferably, the width of the inter-dimple spaces 20, 22 is in the range of 0.005 to 0.012 inches. According to one aspect of the present invention, the widths of the inter-dimple spaces 20 and 22 vary over the entire ball 10. Furthermore, the spaces 20 and 22 may intersect (partly collide) in a circular inter-dimple space 24. In the illustrated dimple pattern, the thick space 20 intersects only the other thick space 20 or the circular space 24. Similarly, the narrow space 22 intersects only other narrow spaces 22 or circular spaces 24. Further, each sample 12 is separated from the first adjacent dimple by a thick space 20 and separated from the second adjacent dimple by a narrow space 22. In other words, the first leg of each triangular dimple 12 is defined by the thick space 20, and the second leg is defined by the narrow leg 2. The third leg is adjacent to the thick space 20 or the narrow space 22. This pattern is repeated across the entire surface of the golf ball 10, so that the land area 13 changes on the surface of the golf ball 10. It will be apparent to those skilled in the art that this dimple pattern is only one of many possible dimple patterns that change the land area.

  In the embodiment shown in FIG. 3, the relatively thick space 20 and the relatively narrow space 22 are each constant over the entire surface of the golf ball 10. In other words, in this embodiment, each dimple 12 is separated from the adjacent dimple 12 in one of two widths. Alternatively, the space between the dimples may change in one identifiable section. For example, in another embodiment, the space between the dimples in the pattern of the dimple 12 may be formed using three or more widths. There may be any number of different inter-dimple spaces in a section. Whatever the actual width of the spaces between the individual dimples, the width is preferably constant between the polygonal dimples. That is, the sides of the adjacent polygonal dimples are parallel to each other.

  Further, in the embodiment shown in FIG. 3, all the circular spaces 24 have the same diameter over the entire surface of the golf ball 10. However, the diameter may vary in other embodiments. For example, each circular space 24 may have a different diameter, and the diameter of any circular space 24 may be selected from a set of predetermined diameters (eg, 2, 3, 4, etc.).

  In addition to polygonal and circular dimples, the inter-dimple space of the present invention is applicable to other types of dimples, for example polygonal dimples on a sphere disclosed in US Publication 2003/0158002. Other types of suitable dimples include polygonal dimples separated by a cylindrical lattice as described in U.S. Pat. No. 6,290,615, iso-diametrical dimples (described below) as described in U.S. Pat. No. 5,377,889. The dimples described in US Pat. No. 4,960,282 are included. It includes a plurality of connecting cylindrical protrusions formed on the surface of the cylindrical lattice ball, and the cross-sectional shape of each protrusion has a vertex at a position farthest from the ball center. An isodiametrical dimple has an odd number of sides, an apex is an arc, and the sides have the same curvature. The superimposed dimples have a boundary formed by arranging two dimples, preferably circular dimples, in an overlapping manner.

  By changing the space between the dimples, the flying distance of the ball can be adjusted by finely adjusting a very efficient dimple pattern without switching to another dimple pattern. By fine-tuning the efficient dimple pattern, you can experiment with completely different dimple patterns, or change the COR by changing the composition of the core and cover, and get the desired results more reliably. realizable. For example, as described above, by increasing at least some of the spaces between the dimples, the dimple covering portion can be selectively reduced, and the distance that the high-efficiency golf ball flies upon impact can be kept within the USGA distance constraint.

  Another embodiment of the invention is shown in FIG. 4 and illustrates this aspect of the invention. This embodiment is similar to the embodiment of FIG. 3 in that the golf ball 10 has a dimple 12 pattern on its outer surface. The pattern of the dimple 12 is the same as that shown in FIG. The dimples 12 are preferably triangular, and the inter-dimple spaces are a relatively thick inter-dimple space 20, a relatively narrow inter-dimple space 22, and a circular inter-dimple space 24. However, in this embodiment, the inter-dimple spaces 20, 22, 24 are wider and larger than the corresponding ones of the embodiment shown in FIG. As a result, the land area 13, that is, the surface area of all the inter-dimple spaces 20, 22, 24 of the golf ball 10 shown in FIG. 4, is significantly larger than the land area shown in FIG. As described above, the larger the proportion of the surface area allocated to the land area 13, the worse the aerodynamic efficiency of the golf ball. The golf ball can be redesigned easily by simply changing the size of the inter-dimple spaces 20, 22, 24 without returning the dimple pattern.

  Alternatively, when the flight distance becomes too short with a specific combination of materials, the width of the space between the dimples is narrowed, that is, the dimple pattern shown in FIG. 4 is shifted to the dimple pattern shown in FIG. Thus, the aerodynamic efficiency can be increased. In the preferred embodiment, the spaces 20, 22 have a width equal to or close to 0.0001 to 0.01 inches wide, preferably 0.0005 to 0.001 inches. These spaces not only intersect the circular inter-dimple spaces 24, but preferably bisect the circular inter-dimple spaces. Adjacent spaces 20, 22 preferably form an acute angle with each other. As a result of testing with the ball and all other elements of the test identical, the flight distance generally increased as the dimple coverage increased. Therefore, it is preferable for many types of balls to realize a dimple design with as high a coverage as possible. As discussed above, the integrated land area is preferably less than 40% of the total surface area of the spherical surface of the golf ball 10. Further, the region of the circular land 24 can be formed by including both a non-circular dimple and a circular dimple instead of the circular dimple. Accordingly, in this embodiment, the linear land elements 20 and 22 intersect the circular dimples and bisect them.

  Yet another embodiment of the present invention is shown in FIG. In this embodiment, the dimple 12 includes both a non-circular recess 12A and a circular recess 12B. The sides of the non-circular dimple 12A (here, a triangular polygon) are substantially parallel to each other. As a result, various inter-dimple spaces, relatively thick inter-dimple spaces 20 and relatively narrow inter-dimple spaces are defined. The circular recess 12B is in contact with the inter-dimple spaces 20, 22 at the slightly rounded end, and the inter-dimple spaces 20, 22 merge with the circular recess 12B. This pattern is repeated across the surface of the golf ball 10. It is easy for those skilled in the art to handle the ratio of the total surface area allocated to the land region 13 by changing the width of the inter-dimple spaces 20 and 22 as in the embodiment shown in FIGS. Will understand. Furthermore, it is easy for those skilled in the art that the circular inter-dimple space 24 shown in FIGS. 3 and 4 may alternatively be a circular recess such as the circular recess 12B shown in FIG. Will understand.

  The space between the dimples of the present invention is also a prominent landmark of the ball. Such prominent landmarks allow the golfer to align the goal with the hole or putter, making it easier for the golfer to play. Also, by adding prominent landmarks formed by various inter-dimple spaces to the individual designs of high efficiency balls, the balls can be easily distinguished from those of other private companies. In addition, individual golfers can easily distinguish their balls during play. Furthermore, the differentiated pattern can produce a ball with inconspicuous joints and dividing lines, and can improve the commercial value.

  The present invention is described herein in terms of aerodynamic criteria, defined by the magnitude and direction of aerodynamic forces, in the range of spin rates and Reynolds numbers that cover the flight regime of typical golf ball trajectories. The These aerodynamic criteria and forces are described below.

  The force acting on the golf ball in flight is calculated by Equation 1 as shown in FIG.

F = F _L + F _D + F _G (Formula 1)
Where F = total force vector acting on the ball F _L = lift vector F _D = drag vector F _G = gravity vector

The lift vector (F _L ) acts in a direction determined by the outer product of the spin vector and the velocity vector. The drag vector (F _D ) acts in the exact opposite direction of the velocity vector. The magnitudes of lift and drag in equation 1 are calculated by equations 2 and 3, respectively.

F _L = 0.5C _L ρAV ² (Formula 2)
F _D = 0.5C _D ρAV ² (Formula 3)
Where ρ = air density (slugs / ft ³ )
A = projection area of ball (ft ² ) ((π / 4) D ² )
D = ball diameter (ft)
V = ball speed (ft / s)
C _L = Dimensionless lift coefficient C _D = Dimensionless drag coefficient

Lift and drag coefficients are used to quantify the force applied to the ball in flight and depend on air density, air speed, ball speed and spin rate. All the effects of these parameters are grasped by two dimensionless parameters: spin rate (SR) and Reynolds number (N _re ). Spin rate is the rotational surface velocity of a ball divided by the ball velocity. The Reynolds number quantifies the ratio of inertial force to viscous force acting on the surface of a ball moving in the air. SR and _Nre are calculated by the following equations 4 and 5.

SR = ω (D / 2) / D (Formula 4)
N _re = DVρ / μ (Formula 5)
Where ω = ball rotation rate (radians / s) (2π (RPS))
RPS = ball rotation rate (rotation / s)
V = ball speed (ft / s)
D = ball diameter (ft)
ρ = air density (slugs / ft ³ )
μ = absolute viscosity of air (lb / ft-s)

There are many suitable methods for determining the lift and drag coefficients for a range of SR and _{N re} a predetermined range, These include, the use of indoor test area with the track screen (ballistic screen) technology included. U.S. Pat. No. 5,682,230 discloses the use of a series of orbit screens to determine lift and drag coefficients. US Pat. Nos. 6,186,002 and 6,285,445 disclose methods for determining lift and drag coefficients for a range of speeds and spin rates using a room test area. Here, the value of _{C L} and _{C D} is associated with the SR and _{N re} for each shot. Refer to these patent documents for details. Those skilled in golf ball aerodynamic tests can easily determine lift and drag coefficients using the indoor test area or alternatively using a wind tunnel.

Ａｎｇｌｅ＝ｔａｎ^−１（Ｃ_Ｌ／Ｃ_Ｄ） （式７） The sky characteristics of a golf ball can be quantified by two parameters, which describe lift and drag simultaneously. That is, (1) the magnitude of the aerodynamic force (Cmag) and (2) the direction of the aerodynamic force (Angle). Here, it has been found that the flight performance can be improved by selecting the dimple pattern and the dimple profile so as to satisfy the criteria of the preferred size and orientation. Since the magnitude and angle of the air force are related to the lift coefficient and drag coefficient, the air coefficient magnitude and angle are used to determine the preferred criteria. The size and angle of the empty body coefficient are defined by Equation 6 and Equation 7 below.

Angle = tan ⁻¹ (C _L / C _D ) (Formula 7)

To ensure consistent flight characteristics regardless of the direction of the ball, percent deviation (percent deviation) plays an important role Cmag for each SR and _{N re.} The percent deviation of Cmag is calculated according to Equation 8. Here, the ratio of the absolute value of the difference between the Cmags of any two orientations to the average value of the Cmags of these two orientations is multiplied by 100.
Percent deviation Cmag
= | (Cmag1-Cmag2) | ((Cmag1 + Cmag2) / 2) × 100 (Equation 8)
However, Cmag1 = Cmag of orientation 1 and Cmag2 = Cmag of orientation 2.

  The percent deviation is preferably about 6 percent or less so that flight characteristics are consistent. More preferably, the Cmag deviation is about 3 percent or less.

  Aerodynamic asymmetries typically result from the separation lines inherent in the dimple arrangement or the separation lines associated with the manufacturing process. The percent Cmag deviation is preferably the Cmag value measured in the axis of rotation perpendicular to the plane of the separation line, broadly referred to as the poles horizon “PH” orientation, and the orientation perpendicular to PH, broadly pole over. Obtained using the Cmag value measured with what is referred to as the pole “PP” orientation. The largest aerodynamic asymmetry is generally measured between the PP and PH orientations. The Cmag percent deviation outlined above applies to the PH and PP orientations as well as any other two orientations. For example, when using a specific dimple pattern of a large circle with shallow dimples, it is necessary to measure different orientations. The axis of rotation used to measure symmetry in the previous example scenario would be orthogonal to a plane that matches this described by the previous large circle.

Also, Cmag and Angle criteria for golf balls with a nominal diameter of 1.68 and a standard weight of 1.62 ounces are useful for obtaining similarly optimized criteria for golf balls of any size and weight. It is thought that it is an important measure. Any preferred aerodynamic criteria can be adjusted according to Equations 9 and 10 to obtain Mmag and Angle for golf balls of any size and weight.

Golf balls made in accordance with the present invention have characteristics similar to those discussed in US Pat. No. 6,729,976. For this, see the patent literature. Table 1 shows the aerodynamic criteria of the golf ball of the present invention, where the flight distance is increased. Criteria are defined as low, medium and high Cmag and Angle for 8 combinations of SR and NRe. Cmag and Angle golf balls that are between low and high values are preferred. More preferably, the golf ball of the present invention has Cmag and Angle values in the range delineated by low and medium values in Table 1. The Cmag values drawn in Table 1 are consistent with USGA size and weight rules. The dimensions and size of the golf balls used in the aerodynamic criteria of Table 1 are 1.68 inches and 1.62 ounces, respectively.

  Other predicted ball force characteristics of golf balls are described in detail in US Pat. No. 6,729,976, which should be referred to as appropriate.

  Although the invention has been described in various ways, it should be understood that the various features of the embodiments of the invention described above may be combined singly or in combination. For example, the dimple depth may be the same for all dimples. Alternatively, the dimple depth may be altered throughout the golf ball. Further, the dimple depth may be decreased to increase the flight trajectory of the ball, or the depth may be increased to decrease the flight trajectory. The present invention is not limited to the embodiments, and various modifications can be made without departing from the spirit of the present invention.

1 is a front view of a conventional golf ball having triangular dimples. FIG. 6 is a front view of another conventional golf ball having hexagonal and pentagonal dimples. 1 is a front view showing a golf ball having a dimple pattern according to an embodiment of the present invention. It is a front view which shows the golf ball which comprises the dimple pattern by 2nd implementation of this invention. It is a front view which shows the golf ball which comprises the dimple pattern by 3rd implementation of this invention. It is a figure explaining the force which acts on a golf ball

Explanation of symbols

10 Golf ball 12 Dimple 13 Land area 20, 22, 24 Space between dimples

Claims (8)

The outer land surface,
A plurality of non-circular dimples;
The outer land surface separates the plurality of non-circular dimples;
The outer land surface is
A plurality of elongated first land spaces having a substantially constant width;
A plurality of elongated second land spaces having a substantially constant width;
The first land space and the second land space extend so as to intersect with each of the plurality of circular land portions or each of the plurality of circular dimples distributed on the surface of the ball. A golf ball having a width different from that of the second land space .   The golf ball according to claim 1, wherein the first land space and the second land space extend so as to connect the adjacent circular dimples.   The golf ball according to claim 1, wherein the first land space and the second land space extend so as to connect the circular land portions.   The golf ball of claim 1, wherein the plurality of non-circular dimples includes at least one polygonal dimple. 2. The golf ball according to claim 1, wherein the area of the outer land surface is 40 % or less of the entire surface area of the golf ball. 2. The golf ball according to claim 1, wherein the area of the outer land surface is 25% or less of the entire surface area of the golf ball. The outer land surface,
A plurality of non-circular dimples;
The outer land surface has a plurality of long land elements separating the plurality of non-circular dimples and having a width that is substantially constant along a length direction thereof. Each of the plurality of circular land portions distributed on the surface of the ball so as to intersect with each of the plurality of circular dimples, and the plurality of land elements include a plurality of land elements having at least a first width and the plurality of land elements. A golf ball comprising a plurality of land elements having a second width different from the first width.   The golf ball according to claim 7, wherein the land elements intersect at an acute angle to equally divide the circular land portion or the circular dimple.

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