WO2009054684A2

WO2009054684A2 - Golf ball having arrangement structure of dimple

Info

Publication number: WO2009054684A2
Application number: PCT/KR2008/006269
Authority: WO
Inventors: Jae-Hoon Lee
Original assignee: Jae-Hoon Lee
Priority date: 2007-10-25
Filing date: 2008-10-23
Publication date: 2009-04-30
Also published as: WO2009054684A3

Abstract

In the dimple arrangement structure of a golf ball of the present invention, a plurality of main dimples are regularly arranged so as to be extended over at least one equator line of the golf ball surface, and the distances to the equator line and each of main dimple centers are formed within 1/2 of the radius of said main dimple. Also, on the golf ball of the present invention, lines linking the main dimple centers are formed on the equator line. Therefore, the present invention makes stable putting alignment possible when aligning and placing a golf ball on the green regardless of the form in which the golf ball is held during the alignment of a putting line.

Description

GOLF BALL HAVING ARRANGEMENT STRUCTURE OF

DIMPLE

Technical Field

[1] The present invention relates to a golf ball having various arrangement structures of dimples, and more specifically to a dimple arrangement structure of a golf ball in which a plurality of dimples formed concavely on the surface of the golf ball are variously arranged so as to improve the performance of the golf ball such as the flying distance and straight advancing properties. Background Art

[2] In general, a golf ball is made with dimples arranged on the upper hemisphere and lower hemisphere based on the centerline. It is because there is a bonding line, which is a joining portion of the golf ball. Namely, the outer surface of dimples cannot be formed unless dimples are arranged above and below or left and right of the bonding line of the golf ball.

[3] To make a golf ball, a golf ball injection mold is divided into the upper hemisphere and lower hemisphere, and the upper and lower hemisphere molds on which dimple shapes are formed in relief are made. And an inner nucleus (core) of elastic material having elastic force is put in a space provided between the upper and lower hemisphere molds, and the hemisphere molds having dimples in relief are matched with each other. Next, outer skin (cover) material is injected into the space provided between the upper and lower hemisphere molds that surround the outside of the elastic core to prepare a golf ball.

[4] When the cover is completely hardened in this state, both sides of the hemispheric upper and lower molds are opened, and the hardened cover with the inner core enveloped therein is trimmed well to finish a golf ball. In this process, a bonding line appears clearly on the outside of the golf ball.

[5] Recently with the development of the technology of manufacturing the mold owing to the technology of injection-molding golf balls, a bonding line that joins the bonded portion between dimple and dimple is formed, but it is difficult to find this bonding line. And the left and right curvature of a flying golf ball is formed uniformly in a complete 360 direction so as to maintain air flow around the golf ball equally, so it has an advantage of making flight uniform.

[6] Fig. 1 is a plan view showing a putting line of a conventional golf ball, Fig. 2 is a plan view showing an example of a bonding line of a conventional golf ball, Fig. 3 is a plan view showing another example of the bonding line of a conventional golf ball, Fig. 4 is a front view showing the state of alignment by the putting line of the conventional golf ball, and Fig. 5 is a front view showing the state of placement by the putting line of the conventional golf ball.

[7] As shown in Figs. 1 to 3, a conventional golf ball has dimples arranged above and below or left and right of the bonding line BL. The centerline dividing the golf ball into the upper hemisphere and lower hemisphere based on the diameter of the golf ball is formed as an equator line C, and along this equator C is formed a putting line PL.

[8] A golf ball should have an elastic core therein, so when the golf ball is hit, flight is possible by elastic force of the core. Therefore, an elastic core is inserted and an injection molding process is carried out to envelop the elastic core with the cover to manufacture a golf ball having dimples. At this time, the cutting line where the top and bottom of the molds touch each other is called a bonding line.

[9] This bonding line is left clearly on the golf ball, and the bonding line, which is the bonded portion, affects the increase and decrease of the spin quantity during the flight and hit of the golf ball, and also greatly affects the putting on the green, sometimes causing mistakes in estimation of the travel of the golf ball.

[10] Therefore, recently the golf ball manufacturers form the seam, that is, the bonding line, which is the bonded portion, zigzag in the protruded portion of the outside of the golf ball where the dimples are connected one after another by mold injection, as shown in Fig. 2, or zigzag separated by the height of the dimple above the centerline of the golf ball. Also, as shown in Fig. 3, the bonded portion, which is the bonding line, is formed zigzag separated by the height of the dimple below the centerline.

[11] In such cases, it is possible to make golf balls on which the equator line cannot be seen, since the boundary between dimples is connected by avoiding the dimples on the outer circumference of the golf ball so that ordinary people cannot find it.

[12] However, in the preparing method of manufacturing companies, the dimples are arranged invariably above and below the centerline, as shown in Fig. 1, Fig. 2 and Fig. 3, based on the centerline passing the center of the golf ball, that is, the bonded portion bisecting the top and bottom portions.

[13] In such a case, the putting line PL does not pass the center of the dimple, so the formation of the putting line becomes unstable, and dimples are scattered above and below or left and right of the bonding line BL, so there is a problem that the equator line C cannot be found.

[14] In the dimple arrangement structure of Fig. 1, the centerline itself becomes the putting line, so when a golfer aligns such a golf ball with the putting line, the golf ball is inclined sideways on the green when he lets go of the golf ball after he finishes with the alignment, as shown in Fig. 4. Therefore, if the golfer putts looking down the initial putting line, it does not follow the same alignment as the initial putting line. [15] As shown in Fig. 2, in the case of joining the bonded portion, the bonded portion is made on the outer circumference of the golf ball on the hill between dimples, which is known as the dimple mountain, so there is a problem that the inclining phenomenon is worsened if the putting line is located on this line.

[16] And as shown in Fig. 3, dimples are arranged above and below the centerline, which is like a boundary, and after passing any dimple on one line above the centerline, the bonded portion is formed while passing zigzag any dimple on one line below the centerline. But still, as shown in Fig. 3, when a conventional golf ball is let go after alignment, the phenomenon of the putting line, the centerline, being inclined, happens.

[17] In the dimple arrangement structure of Fig. 2, breakaway of the golf ball from the mold after injection molding is easy, but since the bonded portion is overlapped zigzag on the centerline, the polishing process is difficult, and there is a fear that the golf ball could be easily inclined when aligning the putting line.

[18] The method of designing the bonded portion in the dimple arrangement structure of

Fig. 3 has a disadvantage that breakaway of the golf ball after injection molding is more difficult than the dimple arrangement structure of Fig. 2 and the rejection rate is high. Also, the dimple arrangement structure of Fig. 3 goes through a polishing process after injection molding, so it is easy to remove all the unnecessary miscellaneous dust in the bonded portion at the time of injection of the golf balls, but it has a problem that productivity is lowered due to difficulty at the time of breakaway from the mold.

[19] Nevertheless, the putting line of such a golf ball is more advantageous than the injection molding of the dimple arrangement structure of Fig. 2. However, both have the problem still remaining that the golf ball inclines after aligning the putting line.

[20] In the golf ball where the putting line PL marked on the golf ball is placed above and below or left and right of the equator line C, the putting line PL is marked on the equator line C in some cases. In such cases, as shown in Fig. 4, the putting line PL is aligned by estimating a virtual path on which the golf ball rolls by taking into consideration the inclination with the hole cup on the green.

[21] Then, as shown in Fig. 5, because the putting line PL does not pass the center of dimple, the boundary surface between dimples matches with the equator line C, so the putting line PL is inclined left or right at a given angle by the dimple hump. In such a case, there is a problem that it is not possible to send the golf ball accurately in the estimated direction.

[22] As described above, the golf ball is made up of the core (inner nucleus) having an elastic force and the cover, and on the outside of the cover, that is, the surface of the golf ball, there exist dimples that improve the flying distance of the golf ball. For these dimples, there is a honeycomb type or circular type as well as a dish type or frying pan type. [23] In the case of the most popular type of golf ball, the number of dimples existing on the surface of the golf ball is usually 260 to 480, and golf balls with these dimples arranged in various forms are available on the market.

[24] And the dimple arrangement structure of a golf ball is being researched in various methods according to the characteristics of each manufacturing company, and research on the arrangement of dimples is expected to continue in the future in order to have the effects recognized by the consumers.

[25] The ratio of dimples to the surface area of the golf ball, namely, the dimple ratio, could be normally in the range of 75 to 95%, and the better a golf ball has the dimple arrangement, the higher its dimple ratio can be effectively increased.

[26] As for the ratio of the dimple area to the surface area of the golf ball, which is the optimum condition of ball hitting feel and lift, 85% can be said to be the best, but until now we have been forced to play golf with balls having a less than optimum ratio due to the development of the core, the development of golf clubs and the rules and regulations of golf. In view of the estimation and regulation of future golf games foreseen like this, the research on the most ideal dimple pattern of the golf ball is estimated to be changed variously according to changes in the golf industry, and it is expected to be improved and advanced in various ways.

[27] As an example, in order to send the golf ball as accurately as possible to the estimated target point, due to core elastic force and the repulsive force of the head for long flying distance of golf club, a conventional golf ball until now has had more than 480 dimples, but recently it is changing rapidly toward a dimple pattern having around 300 dimples.

[28] Fig. 6 is a view showing a dimple arrangement structure of a conventional golf ball.

This is a dimple arrangement structure composed of a diamond or rhombic shape which is divided into five zones based on the North Pole and five zones based on the South Pole. Fig. 7 is a perspective view showing the dimple arrangement structure of such a conventional golf ball.

[29] Fig. 8 is a view showing a dimple arrangement structure of another conventional golf ball. It is the dimple arrangement structure of a conventional golf ball in which 4 hexagonal zones are formed around the North Pole and 4 are formed around the South Pole, so that a total of 8 hexagonal zones are formed, and quadrangular zones are formed between the 8 hexagonal zones respectively, so that a total of 6 quadrangular zones are formed. Fig. 9 is a perspective view of the dimple arrangement structure of the conventional golf ball having 8 hexagonal zones and 6 quadrangular zones.

[30] Although such a dimple arrangement structure of a conventional golf ball has a symmetric structure on the top, bottom, left and right of the golf ball, the transverse lines and longitudinal lines of the top touch each other on the side, so the ratio of dimples to the surface area is reduced to cause a decrease of drag and the lowering of lift generation.

[31] Also, in the dimple arrangement structure of the conventional golf ball, eight hexagonal zones are formed to exist, but if we look at the number of the dimples in the hexagon, the number is to be less in the dimple group in the periphery than the dimple group in the center.

[32] If we look at the intersection portions between the hexagonal zones, the portions where dimples intersect each other should exist like in the quadrangular zones, but the widths and heights touch each other in a straight line. Therefore, this also is an arrangement structure in which the problem of the decrease of drag and the lowering of lift generation occurs frequently in the intersection like in the quadrangles. Disclosure of Invention Technical Problem

[33] The present invention is to solve the conventional problems as described above with an object to provide a dimple arrangement structure of a golf ball, whereby the straight advancing properties during the putting of the golf ball are improved since stable putting alignment is possible regardless of the form in which the golf ball is held and placed on the green during the alignment of a putting line, and it is easy to process the outer surface of the golf ball, and it is possible to maintain the uniformity of dimple arrangement.

[34] Another object of the present invention is to provide a dimple arrangement structure of a golf ball, whereby the air flow on the left and right of and above and below the golf ball that is hit and flying is uniform owing to the symmetrically arranged golf ball dimples, and drag is reduced since the dimples are arranged symmetrically, and it is possible to increase lift. Technical Solution

[35] To accomplish the object of the present invention, there is provided a golf ball having an arrangement structure of dimples characterized in that: a plurality of main dimples are regularly arranged so as to pass at least one equator line of the golf ball surface, a distance between said equator line and each main dimple center is within 1/2 of said main dimple radius, and a sum of the diameter of said main dimples is more than 1/2 of the length of said equator line.

[36] In accordance with the present invention, a line linking the centers of each of main dimples is formed on the equator line. In accordance with the present invention, the main dimples are the dimples that are distributed the most, more than 50% of each zone or the total of the dimples, and it is preferable to form dimples with a variation in the diameter thereof of within ±10%. [37] In accordance with the present invention, subdimples smaller than said main dimples are arranged between said main dimples. In accordance with the present invention, said subdimples are arranged on a line linking said main dimple centers or in symmetry above and below the line linking said main dimple centers.

[38] In accordance with the present invention, the bonding line of said golf ball does not pass each of said main dimples and is formed in a concavo-convex form so as to be symmetrical above and below said equator line.

[39] In accordance with the present invention, said bonding line is formed repetitively in a concavo-convex form so as to sequentially pass the top of at least one main dimple, the equator line, the bottom of at least one main dimple and the equator line. In accordance with the present invention, a putting line is formed on the equator line over which said main dimples are continually arranged.

[40] In accordance with the present invention, on the surface of said golf ball, 4 continuous hexagonal zones, 2 hexagonal zones respectively above and below any one hexagonal zone of said 4 hexagonal zones, and 8 roughly triangular zones between said hexagonal zones are divided to be formed by virtual dividing lines, and dimple clusters are placed in each zone, and the equator line that said main dimples pass is formed on the centerline of the 4 continuous hexagonal zones.

[41] In accordance with the present invention, on the surface of said golf ball, 8 quadrangular zones formed so as to be in symmetry centering on each of both polar points, and 4 quadrangular zones inserted between said 8 quadrangular zones formed in symmetry are divided to be formed by a virtual dividing line, and dimple clusters are placed in each zone, and the equator line that said dimples pass is formed on the centerline of said 4 inserted quadrangular zones.

[42] In accordance with the present invention, said virtual dividing line consists of both polar points, 8 middle points MPl and MP2, and a partitioning line connecting 4 equator points EP to each other, wherein said middle points MPl and MP2 are located at the middle point of the dividing line that connects each polar points and the point where the cross line that divides the golf ball into four equal parts based on the polar point meets the equator line C, and said equator point EP is located at the center of two points where each of the cross lines that divide the golf ball into four equal parts based on the polar point meets the equator line C.

[43] In accordance with the present invention, the dimples in the rim portion of said quadrangular zone dimple cluster are placed within or on said partitioning line.

[44] In accordance with the present invention, large dimples larger than the dimple placed within each zone are placed on said both polar points and said equator point, and small dimples smaller than the dimple placed within each zone are placed around it.

[45] In accordance with the present invention, said quadrangular zone dimple cluster has 5 to 6 dimples placed along said partitioning line.

[46] In accordance with the present invention, on the surface of said golf ball, 5 respective quadrangular zones are divided to be formed by a virtual dividing line based on both polar points, so that the 5 quadrangular zones partitioned based on one polar point are formed by half in mesh with the 5 quadrangular zones partitioned based on the other polar point, and dimple clusters are placed in each zone, and the equator line that said main dimples pass is formed on the centerline of the half portion of said quadrangular zones in mesh with each other.

[47] In accordance with the present invention, the dimples placed in the center of the half portion of each of said quadrangular zones have protuberances formed on the bottom or protruded portions formed around the lateral portion.

Advantageous Effects

[48] According to the present invention, the putting line is formed on the equator line passing the center of the dimples arranged in a line, so that stable putting alignment becomes possible regardless of the form in which the golf ball is held and placed on the green during the alignment of the putting line.

[49] Also, in the present invention the advance of the golf ball during the putting of the golf ball passes the center of the dimples, so it provides an effect that the straight advancing properties are improved during the putting of the golf ball.

[50] The present invention forms the putting line on the bonding line of the golf ball, so it provides an effect that the straight advancing properties are improved during the putting of the golf ball.

[51] According to the present invention, the bonding line of the golf ball is formed in a zigzag shape centering on the equator line without passing the main dimples, so it is easy to process the outer surface of the golf ball and it is possible to maintain the uniformity of dimple arrangement.

[52] The present invention arranges the dimples of the golf ball symmetrically, so the symmetry of the left, right, top and bottom of the dimple is regular and the left-right symmetry is exact, so that it provides an effect that the air flow on the left and right of and above and below the golf ball that is hit and flying is maintained uniformly.

[53] The present invention divides the surface of the golf ball into equal spherical dodecahedrons or decahedrons in order to arrange surface dimples of the golf ball in a form of clusters of a uniform shape, and dimples having identical shapes and sizes are formed in the 12 or 10 equally divided parts, so that it provides an effect that the golf ball can make an exact symmetrical structure in any directions of up, down, left and right.

[54] The present invention makes the dimple arrangements and sizes equal in the portions divided equally into dimple clusters of the quadrangular zones, so that it provides an effect that drag can be reduced and lift can be increased. Brief Description of the Drawings

[55] The above objects, features and advantages of the present invention will become more apparent to those skilled in the related art in conjunction with the accompanying drawings. In the drawings:

[56] Fig. 1 is a plan view showing a putting line of a conventional golf ball;

[57] Fig. 2 is a plan view showing an example of a bonding line of a conventional golf ball;

[58] Fig. 3 is a plan view showing another example of the bonding line of a conventional golf ball;

[59] Fig. 4 is a front view showing the state of alignment by the putting line of the conventional golf ball;

[60] Fig. 5 is a front view showing the state of placement by the putting line of the conventional golf ball;

[61] Fig. 6 is a development view showing an example of the dimple arrangement structure of a conventional golf ball;

[62] Fig. 7 is a perspective view of the dimple arrangement structure of a golf ball of Fig.

6;

[63] Fig. 8 is a development view showing another example of the dimple arrangement structure of a conventional golf ball;

[64] Fig. 9 is a perspective view of the dimple arrangement structure of a golf ball of Fig.

8;

[65] Fig. 10 is a plan view showing a centerline of a golf ball in the dimple arrangement structure of a golf ball according to a first embodiment of the present invention;

[66] Fig. 11 is a plan view showing a putting line of the golf ball in the dimple arrangement structure of a golf ball according to the first embodiment of the present invention;

[67] Fig. 12 is a plan view showing a bonding line of the golf ball in the dimple arrangement structure of a golf ball according to the first embodiment of the present invention;

[68] Fig. 13 is a front view showing the state of alignment by the putting line of the golf ball in the dimple arrangement structure of a golf ball according to the first embodiment of the present invention;

[69] Fig. 14 is a sectional view showing the bonding line of the mold of the golf ball in the dimple arrangement structure of a golf ball according to the first embodiment of the present invention; [70] Fig. 15 is a layout showing one example of the dimple arrangement structure of a golf ball according to the first embodiment of the present invention; [71] Fig. 16 is a layout showing another example of the dimple arrangement structure of a golf ball according to the first embodiment of the present invention; [72] Fig. 17 is a layout showing yet another example of the dimple arrangement structure of a golf ball according to the first embodiment of the present invention; [73] Fig. 18 is a development view showing the dimple arrangement structure of a golf b all according to the first embodiment of the present invention; [74] Fig. 19 is an elevation view showing the dimple arrangement structure of a golf ball according to the first embodiment of the present invention; [75] Fig. 20 is a layout showing a dimple arrangement structure of a golf ball according to a second embodiment of the present invention; [76] Fig. 21 is an enlarged view of part E of Fig. 20;

[77] Fig. 22 is a development view showing a bonding line of the dimple arrangement structure of a golf ball according to the second embodiment of the present invention; [78] Fig. 23 is a development view showing another bonding line of the dimple arrangement structure of a golf ball according to the second embodiment of the present invention; [79] Fig. 24 is an elevation view showing the main dimples of the dimple arrangement structure of the golf ball according to the second embodiment of the present invention; [80] Fig. 25 is an elevation view showing another bonding line of a conventional golf ball; [81] Fig. 26 is an elevation view showing a modified example of the bonding line of the dimple arrangement structure of a golf ball according to the second embodiment of the present invention; [82] Fig. 27 is a development view showing a dimple arrangement structure of the golf ball according to a third embodiment of the present invention; [83] Fig. 28 is a perspective view of the dimple arrangement structure of a golf ball of

Fig. 27;

[84] Fig. 29 is a plan view of the dimple arrangement structure of a golf ball of Fig. 27;

[85] Fig. 30 is a view for explaining the quadrangular zones of the dimple arrangement structure of a golf ball according to the third embodiment of the present invention; [86] Fig. 31 is a view showing the configuration of the quadrangular zones in the dimple arrangement structure of a golf ball according to the third embodiment of the present invention;

[87] Fig. 32 is a layout showing quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the third embodiment of the present invention; [88] Fig. 33 is another layout showing quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the third embodiment of the present invention; [89] Fig. 34 is yet another layout showing quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the third embodiment of the present invention; [90] Fig. 35 is an elevation view showing another example of quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the third embodiment of the present invention; [91] Fig. 36 is a layout showing another example of quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the third embodiment of the present invention; [92] Fig. 37 is an elevation view showing one example of quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the fourth embodiment of the present invention; [93] Fig. 38 is a layout showing one example of quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the fourth embodiment of the present invention; [94] Fig. 39 is an elevation view showing another example of quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the fourth embodiment of the present invention; [95] Fig. 40 is a layout showing another example of quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the fourth embodiment of the present invention; [96] Fig. 41 is a development view showing a dimple arrangement structure of the golf ball according to a fifth embodiment of the present invention; [97] Fig. 42 is a front view showing the golf ball according to the fifth embodiment of the present invention; [98] Fig. 43 is a perspective view showing the golf ball according to the fifth embodiment of the present invention; and

[99] Fig. 44 is an enlarged view of part F of Fig. 43.

[100] <Description of the symbols for the major parts of the drawings> [101] 10: main dimple 11: first subdimple [102] 12: second subdimple 100: golf ball [103] C: equator line BL: bonding line [104] PL: putting line CP center of dimple [105] DlO, D20: main dimples DI l, D21: large dimples [106] D12, D22: medium dimples D13, D23: small dimples [107] P: partitioning line

Best Mode for Carrying Out the Invention

[108] Below a preferred first embodiment of the present invention will be described in detail with reference to the accompanying diagrams. [109] Fig. 10 is a plan view showing a centerline of a golf ball in the dimple arrangement structure of a golf ball according to the first embodiment of the present invention, Fig.

11 is a plan view showing a putting line of the golf ball in the dimple arrangement structure of a golf ball according to the first embodiment of the present invention, Fig.

12 is a plan view showing a bonding line of the golf ball in the dimple arrangement structure of a golf ball according to the first embodiment of the present invention, Fig.

13 is a front view showing the state of alignment by the putting line of the golf ball in the dimple arrangement structure of a golf ball according to the first embodiment of the present invention, Fig. 14 is a sectional view showing the bonding line of the mold of the golf ball in the dimple arrangement structure of a golf ball according to the first embodiment of the present invention, Fig. 15 is a layout showing one example of the dimple arrangement structure of a golf ball according to the first embodiment of the present invention, Fig. 16 is a layout showing another example of the dimple arrangement structure of a golf ball according to the first embodiment of the present invention, Fig. 17 is a layout showing yet another example of the dimple arrangement structure of a golf ball according to the first embodiment of the present invention, Fig. 18 is a development view showing the dimple arrangement structure of a golf ball according to the first embodiment of the present invention, and Fig. 19 is an elevation view showing the dimple arrangement structure of a golf ball according to the first embodiment of the present invention;

[110] Unlike the earth a golf ball 100 does not have a definite North Pole and South Pole, so the equator line of the golf ball becomes the centerline bisecting the upper hemisphere and lower hemisphere based on the diameter of the golf ball, and based on this, the apex of the upper hemisphere can be called the North Pole and the apex of the lower hemisphere the South Pole.

[I l l] As shown in Fig. 10, the centerline of the golf ball can be positioned in many directions if a golfer wants to arrange the dimples in such a way that the center CP of the dimples is positioned on the centerline, which is the equator line of the golf ball, and the putting line is formed on the centerline of the golf ball.

[112] If the golfer looks at the golf ball based on one centerline Al and if the golf ball is placed in the vertical direction, the top becomes a first North Pole NO and the bottom becomes a first South Pole SO. And if the dimples are arranged in such a way that another centerline B 1 passes the center CP of the dimples, the top of the centerline B 1 becomes a second North Pole Nl and the bottom becomes a second South Pole Sl. Therefore, if the dimples are arranged in such a way that yet another centerline Cl passes the center CP of the dimples, the top becomes a third North Pole N2 and the bottom a third South Pole S2.

[113] Since there can be a plurality of centerlines even in one golf ball like above, any line passing the center CP of the golf ball dimples in any of 360 directions can become the centerline of the golf ball.

[114] However, the golf ball needs an elastic body called a core therein, and dimples exist on the surface of the cover embracing the elastic core to reduce drag and improve lift. So on the cover embracing the elastic core is generated a joining portion in the injection process of the manufacturing line, and this joining portion is called a seam line of the golf ball.

[115] As shown in Fig. 11 and Fig. 12, in the dimple arrangement structure of a golf ball of the present embodiment, main dimples 10 are arranged in a line along at least one equator line C of the surface of the golf ball 100. Also, the main dimples are arranged in such a way that the equator line C passes the center CP of the main dimples 10. And the main dimples 10 are formed in equal sizes.

[116] Also, the standard dimple arrangement structure is to arrange the dimples in such a way that the center CP of main dimples 10 is located on the equator line C, the centerline of the golf ball 100. In such a dimple arrangement structure, it goes without saying that a plurality of dimples can be arranged in various structures on the upper hemisphere and lower hemisphere of the golf ball 100.

[117] And if a plurality of centerlines are set up based on the equator line C and the center CP of the dimples is positioned on the centerline, it is possible to get a plurality of more effective putting lines PL.

[118] Like this, the dimple arrangement structure of the present embodiment, in which the dimples are arranged in such a way that the center CP of main dimples is located on the equator line C, which is the centerline of the golf ball 100, can completely solve the problem of the conventional golf ball inclining during the alignment of the putting line, so it is effective for putting.

[119] In addition, as shown in Fig. 10, the dimple arrangement structure, in which the dimples are arranged in such a way that the center CP of the main dimples 10 is located on a plurality of centerlines of the golf ball, makes stable putting alignment possible, regardless of the form in which the golf ball is held and placed on the green during the alignment of the putting line PL.

[120] Therefore, as shown in Fig. 13, if the main dimples 10 are arranged in a line along the equator line C, and the main dimples 10 are arranged in such a way that the equator line C passes the center CP of the main dimples 10, and the putting line PL is formed on this equator line C, it is possible to solve the problem of the golf ball inclining during the alignment with its putting line.

[121] Namely, if the golfer aligns the golf ball on the green centering on the putting line PL of the golf ball, it is possible to obtain a more stable putting alignment condition without the inclining of the golf ball 100.

[122] Also, since the main dimples 10 are arranged in a line on the putting line PL, the advance of the golf ball during putting passes the center of the main dimples 10, so it is possible to obtain an effect that straight advancing properties are improved during the putting of the golf ball.

[123] Fig. 14 shows a dimple arrangement structure of a golf ball in which the dimples are arranged in such a way that the center CP of the main dimples 10 is located on the equator line C of the golf ball, so that the putting line PL of the golf ball is not inclined during putting alignment. As shown in drawing, the injection mold is manufactured in such a way that one or a few bonding lines BL are formed above or below the main dimples 10 in a zigzag shape with as much space as is in the interval between the main dimples 10.

[124] Fig. 14 is a sectional view of a golf ball injection mold showing the state in which the cutting line of the golf ball injection mold of the present embodiment matches with the bonding line BL of the golf ball. The mold shown in drawing is composed of an upper mold 210 of the upper hemisphere and a lower mold 220 of the lower hemisphere that are bisected along the equator line C of the golf ball.

[125] In order to prevent the occurrence of an equator line C that divides the main dimples 10 placed on the centerline of the golf ball into an upper plane and lower plane, upper and lower molds are formed in division based on the zigzag shaped curved line. Like this, the cutting line of the upper mold and lower mold can be selectively formed by the manufacturing company in two or more zigzag shapes, in which the cutting line of the upper mold and lower mold passes the tops of one or a few main dimples and, after the centerline, passes the bottoms of one or a few main dimples.

[126] Since the putting line is formed on the equator line that is formed centering on the bonding line of the golf ball, the upper hemisphere and lower hemisphere of the golf ball are symmetrically balanced with each other, so the straight advancing properties are improved during the putting of the golf ball.

[127] As shown in Fig. 15, a structure, in which first subdimples 11 of a size smaller than the main dimples 10 are arranged between the main dimples 10 on the equator line C, is also preferable. This structure can also achieve stable putting alignment by the putting line and straight advancing properties during putting.

[128] Also, it is of course possible that the centerline of the golf ball, namely, the equator line C around the golf ball, passes the centers CP of the main dimples 10 and dimples of various sizes can be arranged on the equator line C regardless of the size of the dimple.

[129] As shown in Fig. 16 and Fig. 17, also the dimple arrangement structure, in which second subdimples 12 are arranged symmetrically at a predetermined interval above and below the equator line C of the golf ball 100, can provide stable putting alignment and straight advancing properties.

[130] Fig. 16 shows a dimple arrangement structure in which second subdimples 12 with a size of about half of the main dimple 10 with the center CP located on the equator line C, which is the centerline of the golf ball 100, are arranged symmetrically above and below the equator line C. In this structure, the dimples are arranged repetitively at a predetermined interval above and below the equator line C.

[131] As shown in the right plane of the golf ball of Fig. 17, the main dimples 10 are placed at the location where the centerline of the golf ball 100 and the center CP of the dimple meet, and the second subdimples 12 that are placed vertically above and below the centerline respectively are placed in more than one line. Next to the subdimples are again located the centers CP of the dimples on the centerline of the golf ball, and more than one main dimple 10 is arranged.

[132] Especially in the centerline portion are arranged the main dimples 10 and the second subdimples 12 repetitively, so that the dimples are arranged with the centers CP of the dimples located on the centerline that partitions the golf ball into the upper hemisphere and lower hemisphere. This is useful in a case where it is difficult to maintain the balance of dimple arrangement even if the size of dimple is varied. In this structure, the main dimples 10 are arranged in such a way that the centers CP of the dimples are located on the centerline of the golf ball, and the second subdimples 12 are located above and below the centerline of the golf ball at less than 50% of the number of dimples around the centerline of the golf ball.

[133] The second subdimples 12 are arranged above and below the centerline in such a way that the golf ball is not inclined in a course of taking a putting after aligning the putting line and letting go the golf ball on the green. Such second subdimples 12 are a preferable arrangement structure, since the alignment state of putting is not inclined from the sufficiently upright state even in the place where the green bottom is not completely flat, by virtue of the main dimples 10 adjacent on both sides, namely, the right main dimples 10 and the left main dimples 10 whose centers CP are located on the centerline.

[134] And it is possible to make a mold in such a way that the bonding line divided into two equal parts or many equal parts is formed so that the tops of the main dimples 10 pass 1/2 of the circumference of the golf ball and the bottoms pass 1/2 of it based on the equator line C of the golf ball. Also, in order to divide the main dimples 10 into many and form various bonding lines according to the dimple shape and dimple size of the golf ball, it is of course possible to make a dimple arrangement structure having divided tops and bottoms on the north hemisphere and south hemisphere of the mold.

[135] However, in such a dimple arrangement structure, if the ratio of the main dimples occupying the equator line C is low, the straight advancing properties may be lowered during the putting of the golf ball, so it is preferable to arrange the main dimples 10 on the equator line C so that the sum of the diameter becomes 50% or more of the total length of the equator line C.

[136] The golf ball 100 whose centers CP of the main dimples 10 are located on the equator line C of the golf ball has a line connecting the centers CP of the main dimples 10 formed, so it has a stability entirely different from the putting line of a conventional golf ball, namely, it is not inclined after aligning the putting line, and the breakaway of the golf ball after injection molding is also easy.

[137] Therefore, in the golf ball 100, in which the equator line C of the golf ball is arranged on the line connecting the centers CP of the main dimples 10, the bonding line BL is formed in a zigzag shape that does not pass the main dimples centering on the equator line C.

[138] As shown in Fig. 18 and Fig. 19, in the dimple arrangement structure of the present embodiment, the surface of the golf ball having dimples formed is divided into 6 hexagonal zones partitioned by a virtual dividing line S and 8 roughly triangular zones partitioned between the hexagonal zones, and dimple clusters are placed in each zone.

[139] In such a dimple arrangement structure of a golf ball, the surface of the golf ball with dimples formed is provided with first to sixth hexagonal zone dimple clusters Pl, P2, P3, P4, P5 and P6 divided by a virtual dividing line S.

[140] Of these, the second to fifth hexagonal zone dimple clusters P2, P3, P4 and P5 are placed continuously in a line on the equator line C, which is a centerline that makes one outer diameter. The first and sixth hexagonal zone dimple clusters Pl and P6 are placed on both sides above and below the third hexagonal zone dimple cluster P3.

[141] The golf ball of the present embodiment is divided into 6 hexagonal zones placed like this and 8 roughly triangular zones formed between the hexagonal zones. In each zone is placed the dimple cluster in which dimples of a predetermined shape are arranged.

[142] In particular, the equator line C passes the second hexagonal zone dimple cluster P2, the third hexagonal zone dimple cluster P3, the fourth hexagonal zone dimple cluster P4 and the fifth hexagonal dimple cluster P5. At this time, the equator line C passes the centers CP of the main dimples 10 that are arranged in a line in the centers of the hexagonal zone dimple clusters P2, P3, P4 and P5.

[143] Accordingly, if the putting line is formed on this equator line C, the golf ball is advanced passing the centers of the dimples during the putting of the golf ball, so it is possible to obtain a stable putting alignment as well as straight advancing properties during the putting by the putting line. Mode for the Invention

[144] Below a preferred second embodiment of the present invention will be described in detail with reference to the accompanying diagrams.

[145] Fig. 20 is a layout showing a dimple arrangement structure of a golf ball according to the second embodiment of the present invention, Fig. 21 is an enlarged view of part E of Fig. 20, Fig. 22 is a development view showing a bonding line of the dimple arrangement structure of a golf ball according to the second embodiment of the present invention, Fig. 23 is a development view showing another bonding line of the dimple arrangement structure of a golf ball according to the second embodiment of the present invention, and Fig. 24 is an elevation view showing the main dimples of the dimple arrangement structure of the golf ball according to the second embodiment of the present invention.

[146] As shown in Figs. 20 to 22, in the dimple arrangement structure of a golf ball of the present embodiment, a plurality of main dimples 10 are arranged in such a way that they pass at least one equator line C of the surface of the golf ball 100 and they are arranged in such a way that their centers CP are within the range off by predetermined distances dl and d2 above and below the equator line C.

[147] Also, it is preferable that the main dimples 10 are arranged in such a way that their centers CP are within the 1/2 range of the radius R of the main dimple above and below the equator line C. Therefore, the separation distance dl+d2 between the centers CP of the main dimples can be represented as "dl + d2 < R". Also, the main dimples 10 may be formed in equal sizes like the first embodiment, or arranged in various diameters and number of dimples. The main dimples 10 of the present embodiment are identical with the first embodiment in the arrangement configuration of the diameter and number of dimples, so specific description is omitted.

[148] Also, the ordinary dimples arranged above and below the main dimples 10 may be formed in the same size as the main dimples as shown in Fig. 18, or be formed and arranged in various sizes as shown in Fig. 19.

[149] In the dimple arrangement structure of a golf ball of the present embodiment, the bonding line BL of the golf ball 100 does not pass each of the main dimples 10, and is formed in a zigzag shape so as to be in up and down symmetry centering on the equator line C.

[150] Such a bonding line BL has zigzag shapes formed repetitively so that it sequentially passes the top of at least one main dimple 10, the equator line C, the bottom of at least one main dimple 10 and the equator line C.

[151] As shown in Fig. 22 and Fig. 23, in the dimple arrangement structure of the present embodiment, the surface of the golf ball having dimples formed is divided into 6 hexagonal zones partitioned by a virtual dividing line S and 8 roughly triangular zones partitioned between the hexagonal zones, and dimple clusters are placed in each zone.

[152] In such a dimple arrangement structure of a golf ball, the surface of the golf ball with dimples formed is provided with first to sixth hexagonal zone dimple clusters Pl, P2, P3, P4, P5 and P6 divided by a virtual dividing line S.

[153] Of these, the second to fifth hexagonal zone dimple clusters P2, P3, P4 and P5 are placed continuously in a line on the equator line C, which is a centerline that makes one outer diameter. The first and sixth hexagonal zone dimple clusters Pl and P6 are placed on both sides above and below the third hexagonal zone dimple cluster P3.

[154] The golf ball of the present embodiment is divided into 6 hexagonal zones placed like this and 8 roughly triangular zones formed between the hexagonal zones. In each zone is placed the dimple cluster in which dimples of a predetermined shape are arranged.

[155] In particular, the equator line C passes the second hexagonal zone dimple cluster P2, the third hexagonal zone dimple cluster P3, the fourth hexagonal zone dimple cluster P4 and the fifth hexagonal dimple cluster P5. At this time, the main dimples 10 are arranged in such a way that their centers CP are within the range between a predetermined distance dl above and a predetermined distance d2 below the equator line C. Also at this time, it is preferable that the main dimples 10 are arranged in such a way that their centers are with the 1/2 range of the maim dimple radius R above and below the equator line C. The main dimples are the dimples that are distributed the most, more than 50% of each zone or the total of the dimples, and it is preferable to form dimples with a variation in the diameter thereof of within ±10%.

[156] And as shown in Fig. 24, if the main dimples 10 are arranged in a zigzag shape, between a main dimple and an adjacent main dimple is formed an insert portion a in which the main dimple 10 is placed in a location that is equal above and below the equator line C.

[157] It is preferable that the length above and below the insert portion a is formed to be 3/4 of the main dimple radius R, since it is difficult to secure the straight advancing properties due to the interference of the main dimples during putting if the length is greater than 3/4 of the main dimple radius R.

[158] A modification example of the bonding line of the present embodiment will be described.

[159] Fig. 25 is an elevation view showing another bonding line of a conventional golf ball, and Fig. 26 is an elevation view showing a modified example of the bonding line of the dimple arrangement structure of a golf ball according to the second embodiment of the present invention.

[160] As shown in Fig. 25, the bonding line of a conventional golf ball is curve-formed along the equator line C, and the dimples are arranged above and below this bonding line, so the putting alignment of straight advancing properties becomes unstable.

[161] In the modification example of the bonding line of the dimple arrangement structure of a golf ball in the present embodiment for overcoming this, the main dimples 10 are arranged in a form in which the line linking the centers of the main dimples 10 bends slowly above and below the equator line C. The bonding line C is formed zigzag so that it alternately crosses the tops and bottoms of these main dimples and the equator line C.

[162] In particular, as shown in Fig. 26, an equator line BLl can be formed in such a concavo-convex form that it passes the bottoms of the three main dimples 10 below and cuts the equator line C longitudinally above and below, and passes the tops of the three main dimples 10 above and cuts the equator line C again longitudinally above and below.

[163] Also, an equator line BL2 can be formed in such a concavo-convex form that it passes the tops of the three main dimples 10 below and cuts the equator line C longitudinally above and below, and passes the bottoms of the three main dimples 10 above and cuts the equator line C again longitudinally above and below.

[164] And the main dimples 10 are arranged in such a way that their centers CP are within the range of 1/2 of the main dimple radius R above and below the equator line C.

[165] Therefore, if the putting line is formed on this equator line C, the advance of the golf ball during putting passes the centers of the dimples, so it is possible to likewise obtain a stable putting alignment and the straight advancing properties during putting by the putting line.

[166] Below a preferred third embodiment of the present invention will be described in detail with reference to the accompanying diagrams.

[167] Fig. 27 is a development view showing a dimple arrangement structure of the golf ball according to the third embodiment of the present invention, Fig. 28 is a perspective view of the dimple arrangement structure of a golf ball of Fig. 27, Fig. 29 is a plan view of the dimple arrangement structure of a golf ball of Fig. 27, Fig. 30 is a view for explaining the quadrangular zones of the dimple arrangement structure of a golf ball according to the third embodiment of the present invention, Fig. 31 is a view showing the configuration of the quadrangular zones in the dimple arrangement structure of a golf ball according to the third embodiment of the present invention, Fig. 32 is a layout showing quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the third embodiment of the present invention, Fig. 33 is another layout showing quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the third embodiment of the present invention, Fig. 34 is yet another layout showing quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the third embodiment of the present invention, Fig. 35 is an elevation view showing another example of quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the third embodiment of the present invention, and Fig. 36 is a layout showing another example of quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the third embodiment of the present invention

[168] As shown in Figs. 27 to 29, in the dimple arrangement structure of a golf ball in the present embodiment, the 8 quadrangular zones formed symmetrically centering on both poles (North Pole and South Pole) respectively, and the 4 quadrangular zones inserted between the 8 quadrangular zones formed symmetrically are divided by a virtual dividing line, and in the zones are placed dimple clusters Kl to K 12, respectively. The equator line C that passes the dimples is formed on the centerline of the inserted 4 quadrangular zones.

[169] As shown in Fig. 30, the virtual dividing line is made up of a partitioning line P of a diamond shape that connects four points, namely, the polar point N, two middle points MPl and MP2 and the equator point EP. The middle points MPl and MP2, which are eight in all, are located at the middle points of two lines Ll and L2 that connect a point where the polar point N and the cross line, which divides the golf ball into four equal parts based on this polar point N, meets the equator line C. The equator points EP, which are four in all, are located at the points where the line L3 that links each of polar points N and S crosses the equator line C.

[170] This will be described specifically below. Namely, it will be explained how to set up the quadrangular zones of the present embodiment, obtain the equator line C based on the North Pole N and South Pole S of the golf ball, and draw a cross line that forms a division of four equal parts based on the two polar points N and S, such that the cross line and the equator line C meet at cross points. At this time, the first line Ll and the second line L2 that connect the polar points N and S and cross points are created, and the middle points MPl and MP2 are located at the middle points of these lines.

[171] And at the point where the line that connects both polar points, namely, the third line L3 that is drawn vertically (in the y-axis direction) from the polar point, meets the equator line C, the equator point EP is formed. Then, at the places where the horizontal line drawn horizontally (in the x-axis direction) from the 1/2 point of the third line L3 meets the first line and the second line, two middle points MPl and MP2 are formed.

[172] The North Pole and these two middle points MPl and MP2 are connected, and again these two middles points MPl and MP2 are connected with the equator point EP, such that eight dimple arrangement zones are formed by a partitioning line P of a diamond shape connected to the North Pole, the equator point EP and two middle points MPl and MP2. Such quadrangular zone dimple clusters Kl to K8 of the dimple arrangement structure provide basic dimple arrangement zones as shown in Fig. 29. Wherein the equator point EP is located at the center of two points where each of the cross lines that divide the golf ball into four equal parts based on the polar point meets the equator line C.

[173] As shown in Fig. 30, if a line is drawn crossing the x-axis and y-axis in the basic dimple arrangement zone, the length of the y-axis becomes the length of the line segment that bisected the circumference between the North Pole N and South Pole S of the golf ball. Namely, "dl = d2"and "d3 = d4".

[174] Since the diameter of the golf ball is 42.67 mm, the circumference of the golf ball is 142.9 mm, that is, 14.29 cm. Thus, the circumference between the North Pole N and South Pole S is 7.146 cm, and 3.572 cm, which is the result of dividing 7.146 cm by two, becomes the length of the y-axis line segment.

[175] As shown in Fig. 31, the x-axis has a length of 3.573 cm for all of the first line Ll and the second line L2 on the spherical surface and the third line L3 that links the North Pole N and the equator point EP. Therefore, it could be seen that the x-axis length is shorter than the y-axis and is longer than the length from the equator point EP to the middle point MPl of one side or the middle point MP2 of the other side.

[176] After obtaining two middle points MPl and MP2 at the North Pole N, suppose the line segment linking the two middle points is an x-axis, and then the length of the line segment from the North Pole N to the point X, when seen in terms of a spherical golf ball, is shorter than the length of the line segment from the North Pole N to the middle point MPl or the length of the line segment from the North Pole N to the middle point MP2. Therefore, in an arrangement structure in which dimples are formed concavely on a spherical body, the cross point and the middle point MP2 are linked vertically to form a dimple.

[177] In other words, it can be seen that the length of the line segment from the North Pole N to point X becomes shorter than the length of the line segment from the North Pole N to the middle point MPl or the length of the line segment from the North Pole N to the middle point MP2.

[178] 12 spherical surfaces of a diamond shape or rhombic shape formed like above are arranged embracing the outside of the golf ball without a gap, as shown in Figs. 27 to 29.

[179] Such a golf ball having 12 zones of equal sizes can provide a partitioning diagram of a dimple arrangement more perfect than any other dimple arrangement structure of a golf ball up to now. Now, depending on how effectively dimples are arranged in such 12 dimple arrangement zones, it is possible to maximize the effect of the dimple arrangement of the present invention.

[180] Fig. 32 is a view showing a dimple arrangement structure in which 6 dimples are arranged on a line segment linking the middle point MPl and the middle point MP2. 6 dimples are placed on the line segment linking the middle point MPl and the middle point MP2, and 5 dimples are placed on the line segment from the North Pole N to the middle point MPl and the line segment from the North Pole N to the middle point MP2.

[181] Therefore, 24 to 25 dimples are placed in such a dimple zone, so that about 288 to 300 dimples are placed in the whole of 12 quadrangular zone dimple clusters. Especially in the portion below the North Pole N and two places above the equator point EP appear small dimple clusters. If the dimples within this zone are configured with a size of 15% of the diameter, it is possible to arrange the dimples effectively even if medium dimple clusters do not appear.

[182] Figs. 27 to 29 are respectively a development view, perspective view and plan view, showing a dimple arrangement structure of a golf ball in which such 12 quadrangular zone dimple clusters are formed.

[183] As shown in Fig. 27 in particular, the dimple clusters placed in the quadrangular zones of the present embodiment consist of the first to 12 quadrangular zone dimple clusters Kl to K 12, and the first to fourth zone dimple clusters Kl to K4 are placed around the North Pole N, and the fifth to eighth quadrangular zone dimple clusters K5 to K8 are placed around the South Pole, and the ninth to 12 quadrangular zone dimple clusters K9 to K12 are placed around the equator line C.

[184] As shown in Figs. 32 to 34, in the quadrangular zone dimple clusters of the present embodiment, 6 dimples are placed on the upper hemisphere and lower hemisphere dividing lines Ll and L2 and the horizontal line connecting the middle points MPl and MP2, and 5 dimples each are placed in a line on the partitioning line P of a diamond shape.

[185] Also, the dimples arranged on the partitioning lines P are conjoined so as to share with the dimples of the adjacent quadrangular zone dimple clusters, and it is of course possible that the dimples are arranged in such a way that their centers pass the partitioning line P.

[186] As shown in Fig. 32, in the quadrangular zone dimple clusters of the present embodiment, large dimples DI l larger than the main dimples DlO within the partitioning line are placed on both polar points and the equator point EP, and one small dimple D 13 is placed around the large dimples 11, and four medium dimples D 12 are placed around the small dimple 13. And the main dimples DlO are placed in the remaining portions.

[187] Also, as another dimple arrangement of the quadrangular zone dimple clusters of the present embodiment, as shown in Fig. 33, it is also possible to place two small dimples D 14 and D 15 of different sizes instead of the small dimple D 13 of the quadrangular zone dimple cluster of Fig. 32.

[188] Also, as yet another dimple arrangement of the quadrangular zone dimple clusters of the present embodiment, as shown in Fig. 34, it is also possible to place three small dimples D 16 and D 17 of different sizes instead of the small dimple D 13 of the quadrangular zone dimple cluster of Fig. 32.

[189] Therefore, in the quadrangular zone dimple clusters of the present embodiment, large dimples larger than the main dimple DlO are placed at both polar points N and S and the equator point EP, and 1 to 2 small dimple clusters and 2 to 4 medium dimple clusters are placed around it, so that a total of 276 to 312 dimples are placed on the outer surface of the golf ball.

[190] Also, as shown in Fig. 35 and Fig. 36, as a placement showing another example of the quadrangular zone dimple cluster of the dimple arrangement structure of a golf ball of the present embodiment, 6 dimples are placed in the direction of the linking line linking between the middle points of the upper hemisphere and lower hemisphere dividing lines.

[191] And in these dimples, likewise as the dimple arrangement structure of Fig. 32, main dimples DlO' large dimples DH' medium dimples D 12' and small dimples D 13' are placed, provided, however, that these dimples are placed within the partitioning line P.

[192] In the present embodiment, 6 dimples are placed in the direction of the linking line linking between the middle points of the upper hemisphere and lower hemisphere dividing lines, but it is of course possible that a maximum of 7 dimples are placed as well.

[193] Below a fourth embodiment of the present invention will be described in detail with reference to the accompanying diagrams.

[194] Fig. 37 is an elevation view showing one example of quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the fourth embodiment of the present invention, Fig. 38 is a layout showing one example of quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the fourth embodiment of the present invention, Fig. 39 is an elevation view showing another example of quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the fourth embodiment of the present invention, and Fig. 40 is a layout showing another example of quadrangular zone dimple clusters of the dimple arrangement structure of a golf ball according to the fourth embodiment of the present invention. [195] As shown in Figs. 37 to 40, in the quadrangular zone dimple clusters of the present embodiment, 7 dimples are placed in a line on the linking line linking between the middle points MPl and MP2 of the upper hemisphere and lower hemisphere dividing lines, and 6 dimples each are placed in a line on the partitioning line P.

[196] In the case of arranging 7 dimples on the x-axis line linking between the middle points MPl and MP2 of the upper hemisphere and lower hemisphere dividing lines, it could be seen that 6 dimples each are placed on the line segment from the North Pole N to the middle point MPl and the line segment from the North Pole N to the middle point MP2.

[197] From this it could be seen that by arranging with the maximum dimple size of 1/7 of the line segment between both middle points MPl and MP2 and the dimple diameter of this size minus around 15%, 34 to 36 dimples are arranged on each of the dimple arrangement zones, and about 420 dimples can be arranged on the whole of the golf ball.

[198] As shown in Fig. 37 and Fig. 38, it can be seen one small dimple D23 and two medium dimples D22 each appearing above and below the large dimple D21 larger than the main dimple D20 at the North Pole N and the equator point EP.

[199] This is a dimple arrangement structure placed identically in all the dimple clusters of the 12 quadrangular zones, and the phenomena of an irregular arrangement of dimples appears at the polar points N and S and near the equator point EP in each quadrangular zone dimple cluster. And if 7 dimples are placed on the line segment linking the middle points MPl and MP2 of Fig. 31 to the line segment, it is possible to arrange dimples as shown in Fig. 38. Namely, like the portion below the dimple D21 of the North Pole N and the portion above the dimple D21 of the equator point EP, it is possible to arrange small dimples D23 and medium dimples D22 equally in all of the twelve dimple zones.

[200] In particular, as shown in Fig. 38, in the quadrangular zone dimple clusters of the present embodiment, large dimples D21 larger than the main dimple D20 are placed at both polar points and the equator point EP, and one small dimple D23 is placed around the large dimples D21, and four medium dimples D22 are placed around the small dimple D23. And in the remaining portion are placed the main dimples D20.

[201] Also, as another placement of dimples of the quadrangular zone dimple clusters of the present embodiment, as shown in Fig. 39 and Fig. 40, it is also possible to arrange two small dimples D25 and D26 of different sizes instead of the small dimple D23 of the quadrangular zone dimple clusters of Fig. 38, and arrange the main dimples D20 instead of the two medium dimples D22 of the four medium dimples D22 placed around the small dimple D23.

[202] Therefore, in the quadrangular zone dimple clusters of the present embodiment, large dimples larger than the main dimple D20 are placed at both polar points N and S and the equator point EP, and 1 to 2 small dimple clusters and 2 to 4 medium dimple clusters are placed around it, so a total of 369 to 444 dimples are placed on the outer surface of the golf ball.

[203] Below a fifth embodiment of the present invention will be described in detail with reference to the accompanying diagrams.

[204] Fig. 41 is a development view showing a dimple arrangement structure of the golf ball according to the fifth embodiment of the present invention, Fig. 42 is a front view showing the golf ball according to the fifth embodiment of the present invention, Fig. 43 is a perspective view showing the golf ball according to the fifth embodiment of the present invention, and Fig. 44 is an enlarged view of part F of Fig. 43.

[205] As shown in Figs. 41 to 43, in the dimple arrangement structure of a golf ball of the present embodiment, 5 quadrangular zones are divided and formed respectively by a virtual dividing line based on both polar points, so that 5 quadrangular zones based on one polar point and 5 quadrangular zones based on the other polar point are formed with the half portion conjoined with each other, and the dimple clusters Al to A5 and B 1 to B5 are placed in the zones respectively. Also, the equator line C over which the main dimples D32 placed in the dimple clusters are extended is formed on the centerline of the half portion of the quadrangular zones that are in mesh each other.

[206] In the golf ball of the present embodiment, the dimple clusters Al to A5 are placed respectively in the quadrangular zones of 5 diamond shapes based on the North Pole in the upper hemisphere, and the dimple clusters Bl to B5 are placed respectively in the quadrangular zones of 5 diamond shapes based on the South Pole in the lower hemisphere.

[207] In such dimple clusters, standard dimples D31 are placed in the edge location of each quadrangular zone, and main dimples D32 are placed in the remaining location.

[208] As shown in Fig. 44, the dimple D33 placed in the center of the half portion of each quadrangular zone has protuberances 30 formed on the bottom and protruded portions 20 around the lateral portion. It is also possible that both are formed in the dimple D33 formed in the center.

[209] Also, the protuberances 30 and protruded portions 20 formed like this in the dimple D33 are divided into a plurality in the same direction to form channels of various shapes such as a linear form and a cross form.

[210] Therefore, the golf ball of the present embodiment can improve the flying distance of the golf ball by increasing the lift during the flight of the golf ball by dint of such a dimple arrangement structure and the configuration of dimples and can increase lift by controlling the up and down air flow in the dimple. Industrial Applicability [211] The present invention can be used as a golf ball having various arrangement structures in which a plurality of dimples are arranged concavely on the outer surface of the golf ball so as to improve the performance such as the flying distance and straight advancing properties of the golf ball.

[212] Although the present invention has been described in connection with the exemplary embodiments illustrated in the drawings, it is only illustrative. It will be understood by those skilled in the art that various modifications and equivalents can be made to the present invention. Therefore, the true technical scope of the present invention should be defined by the appended claims.

Claims

[1] A golf ball having an arrangement structure of dimples characterized in that: a plurality of main dimples are regularly arranged so as to pass at least one equator line of the golf ball surface, a distance between said equator line and each main dimple center is within 1/2 of said main dimple radius, and a sum of the diameter of said main dimples is more than 1/2 of the length of said equator line.

[2] The golf ball according to claim 1, wherein a line linking the centers of each of main dimples is formed on the equator line.

[3] The golf ball according to claim 1, wherein said main dimples are formed in the same sizes.

[4] The golf ball according to claim 1, wherein subdimples smaller than said main dimples are arranged between said main dimples.

[5] The golf ball according to claim 4, wherein said subdimples are arranged on a line linking said main dimple centers or in symmetry above and below the line linking said main dimple centers.

[6] The golf ball according to claim 1, wherein the bonding line of said golf ball does not pass each of said main dimples and is formed in a concavo-convex form so as to be symmetrical above and below said equator line.

[7] The golf ball according to claim 6, wherein said bonding line is formed repetitively in a concavo-convex form so as to sequentially pass the top of at least one main dimple, the equator line, the bottom of at least one main dimple and the equator line.

[8] The golf ball according to claim 1, wherein a putting line is formed on the equator line over which said main dimples are continually arranged.

[9] The golf ball according to claim 1, wherein on the surface of said golf ball, 4 continuous hexagonal zones, 2 hexagonal zones respectively above and below any one hexagonal zone of said 4 hexagonal zones, and 8 roughly triangular zones between said hexagonal zones are divided to be formed by virtual dividing lines, and dimple clusters are placed in each zone, and the equator line that said main dimples pass is formed on the centerline of the 4 continuous hexagonal zones.

[10] The golf ball according to claim 1, wherein on the surface of said golf ball, 8 quadrangular zones formed so as to be in symmetry centering on each of both polar points, and 4 quadrangular zones inserted between said 8 quadrangular zones formed in symmetry are divided to be formed by a virtual dividing line, and dimple clusters are placed in each zone, and the equator line that said dimples pass is formed on the centerline of said 4 inserted quadrangular zones.

[11] The golf ball according to claim 10, wherein said virtual dividing line consists of both polar points, 8 middle points MPl and MP2, and a partitioning line connecting 4 equator points EP to each other, wherein said middle points MPl and MP2 are located at the middle point of the dividing line that connects each polar points and the point where the cross line that divides the golf ball into four equal parts based on the polar point meets the equator line C, and said equator point EP is located at the center of two points where each of the cross lines that divide the golf ball into four equal parts based on the polar point meets the equator line C.

[12] The golf ball according to claim 11, wherein the dimples in the rim portion of said quadrangular zone dimple cluster are placed within or on said partitioning line.

[13] The golf ball according to claim 11, wherein large dimples larger than the dimple placed within each zone are placed on said both polar points and said equator point, and small dimples smaller than the dimple placed within each zone are placed around it.

[14] The golf ball according to claim 11, wherein said quadrangular zone dimple cluster has 5 to 6 dimples placed along said partitioning line.

[15] The golf ball according to claim 1, wherein on the surface of said golf ball, 5 respective quadrangular zones are divided to be formed by a virtual dividing line based on both polar points, so that the 5 quadrangular zones partitioned based on one polar point are formed by half in mesh with the 5 quadrangular zones partitioned based on the other polar point, and dimple clusters are placed in each zone, and the equator line that said main dimples pass is formed on the centerline of the half portion of said quadrangular zones in mesh with each other.

[16] The golf ball according to claim 15, wherein the dimples placed in the center of the half portion of each of said quadrangular zones have protuberances formed on the bottom or protruded portions formed around the lateral portion.