Abstract:
A golf ball approaching zero land area is disclosed herein. The golf ball has an innersphere with a plurality of pyramidal projections. Each of the plurality of projections has an apex that extends to a height to conform with the 1.68 inches requirement for USGA approved golf balls. The plurality of pyramidal projections extend 0.005 inch to 0.015 inch from the innersphere surface. The outermost 0.002 inch of the golf ball has a minimal volume.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     The Present Application is a continuation-in-part application of U.S. patent application Ser. No. 09/442,860, filed on Nov. 18, 1999, now U.S. Pat. No. 6,383,092. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an aerodynamic surface for a golf ball. More specifically, the present invention relates to a golf ball having pyramidal protrusions to effect turbulence during flight of the golf ball. 
     2. Description of the Related Art 
     Golfers realized perhaps as early as the 1800&#39;s that golf balls with indented surfaces flew better than those with smooth surfaces. Hand-hammered gutta-percha golf balls could be purchased at least by the 1860&#39;s, and golf balls with brambles (bumps rather than dents) were in style from the late 1800&#39;s to 1908. In 1908, an Englishman, William Taylor, received a British patent for a golf ball with indentations (dimples) that flew better ad more accurately than golf balls with brambles. A. G. Spalding &amp; Bros., purchased the U.S. rights to the patent (embodied possibly in U.S. Pat. No. 1,286,834 issued in 1918) and introduced the GLORY ball featuring the TAYLOR dimples. Until the 1970s, the GLORY ball, and most other golf balls with dimples had 336 dimples of the same size using the same pattern, the ATTI pattern. The ATTI pattern was an octohedron pattern, split into eight concentric straight line rows, which was named after the main producer of molds for golf balls. 
     The only innovation related to the surface of a golf ball during this sixty year period came from Albert Penfold who invented a mesh-pattern golf ball for Dunlop. This pattern was invented in 1912 and was accepted until the 1930&#39;s. A combination of a mesh pattern and dimples is disclosed in Young, U.S. Pat. No. 2,002,726, for a Golf Ball, which issued in 1935. 
     The traditional golf ball, as readily accepted by the consuming public, is spherical with a plurality of dimples, with each dimple having a circular cross-section. Many golf balls have been disclosed that break with this tradition, however, for the most part these non-traditional golf balls have been commercially unsuccessful. 
     Most of these non-traditional golf balls still attempt to adhere to the Rules Of Golf as set forth by the United States Golf Association (“USGA”) and The Royal and Ancient Golf Club of Saint Andrews (“R&amp;A”). As set forth in Appendix III of the Rules of Golf, the weight of the ball shall not be greater than 1.620 ounces avoirdupois (45.93 gm), the diameter of the ball shall be not less than 1.680 inches (42.67 mm) which is satisfied if, under its own weight, a ball falls through a 1.680 inches diameter ring gauge in fewer than 25 out of 100 randomly selected positions, the test being carried out at a temperature of 23±1° C., and the ball must not be designed, manufactured or intentionally modified to have properties which differ from those of a spherically symmetrical ball. 
     One example is Shimosaka et al., U.S. Pat. No. 5,916,044, for a Golf Ball that discloses the use of protrusions to meet the 1.68 inch (42.67 mm) diameter limitation of the USGA and R&amp;A. The Shimosaka patent discloses a golf ball with a plurality of dimples on the surface a few rows of protrusions that have a height of 0.001 to 1.0 mm from the surface. Thus, the diameter of the surface is less than 42.67 mm. 
     Another example of a non-traditional golf ball is Puckett et al., U.S. Pat. No. 4,836,552 for a Short Distance Golf Ball, which discloses a golf ball having brambles instead of dimples in order to reduce the flight distance to half of that of a traditional golf ball in order to play on short distance courses. 
     Another example of a non-traditional golf ball is Pocklington, U.S. Pat. No. 5,536,013 for a Golf Ball, which discloses a golf ball having raised portions within each dimple, and also discloses dimples of varying geometric shapes such as squares, diamonds and pentagons. The raised portions in each of the dimples of Pocklington assists in controlling the overall volume of the dimples. 
     Another example is Kobayashi, U.S. Pat. No. 4,787,638 for a Golf Ball, which discloses a golf ball having dimples with indentations within each of the dimples. The indentations in the dimples of Kobayashi are to reduce the air pressure drag at low speeds in order to increase the distance. 
     Yet another example is Treadwell, U.S. Pat. No. 4,266,773 for a Golf Ball, which discloses a golf ball having rough bands and smooth bands on its surface in order to trip the boundary layer of air flow during flight of the golf ball. 
     Aoyama, U.S. Pat. No. 4,830,378, for a Golf Ball With Uniform Land Configuration, discloses a golf ball with dimples that have triangular shapes. The total flat land area of Aoyama is no greater than 20% of the surface of the golf ball, and the objective of the patent is to optimize the uniform land configuration and not the dimples. 
     Another variation in the shape of the dimples is set forth in Steifel, U.S. Pat. No. 5,890,975 for a Golf Ball And Method Of Forming Dimples Thereon. Some of the dimples of Steifel are elongated to have an elliptical cross-section instead of a circular cross-section. The elongated dimples make it possible to increase the surface coverage area. A design patent to Steifel, U.S. Pat. No. 406,623, has all elongated dimples. 
     A variation on this theme is set forth in Moriyama et al., U.S. Pat. No. 5,722,903, for a Golf Ball, which discloses a golf ball with traditional dimples and oval shaped dimples. 
     A further example of a non-traditional golf ball is set forth in Shaw et al., U.S. Pat. No. 4,722,529, for Golf Balls, which discloses a golf ball with dimples and 30 bald patches in the shape of a dumbbell for improvements in aerodynamics. 
     Another example of a non-traditional golf ball is Cadorniga, U.S. Pat. No. 5,470,076, for a Golf Ball, which discloses each of a plurality of dimples having an additional recess. It is believed that the major and minor recess dimples of Cadorniga create a smaller wake of air during flight of a golf ball. 
     Oka et al., U.S. Pat. No. 5,143,377, for a Golf Ball, discloses circular and non-circular dimples. The non-circular dimples are square, regular octagonal, regular hexagonal and amount to at least forty percent of the 332 dimples on the golf ball of Oka. These non-circular dimples of Oka have a double slope that sweeps air away from the periphery in order to make the air turbulent. 
     Machin, U.S. Pat. No. 5,377,989, for Golf Balls With Isodiametrical Dimples, discloses a golf ball having dimples with an odd number of curved sides and arcuate apices to reduce the drag on the golf ball during flight. 
     Lavallee et al., U.S. Pat. No. 5,356,150, discloses a golf ball having overlapping elongated dimples to obtain maximum dimple coverage on the surface of the golf ball. 
     Oka et al., U.S. Pat. No. 5,338,039, discloses a golf ball having at least forty percent of its dimples with a polygonal shape. The shapes of the Oka golf ball are pentagonal, hexagonal and octagonal. 
     Although the prior art has set forth numerous variations for the surface of a golf ball, there remains a need for a golf ball having a surface that minimizes the volume needed to trip the boundary layer of air at low speed while providing a low drag level at high speeds. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is able to provide a golf ball that meets the USGA requirements, and provides a minimum land area to trip the boundary layer of air surrounding a golf ball during flight in order to create the necessary turbulence for greater distance. The present invention is able to accomplish this by providing a golf ball with a tubular lattice pattern on a surface of an innersphere. 
     One aspect of the present invention is a golf ball with an innersphere having a surface and a plurality of pyramidal projections disposed on the innersphere surface. Each of the pyramidal projections has a cross-sectional contour with an apex at the greatest extent from the center of the golf ball. The plurality of pyramidal projections form a predetermined pattern on the surface. Each of the pyramidal projections extend from 0.005 inches to 0.015 inches from the innersphere surface. 
     The plurality of pyramidal projections on the golf ball may cover between 20% to 80% of the surface of the innersphere surface. The apex of each of the plurality of pyramidal projections may have a width less than 0.000001 inches. The diameter of the innersphere may be at least 1.67 inches and the height of the apex of each of the plurality of pyramidal projections maybe at least 0.005 inches from the surface of the innersphere. The golf ball may also include a plurality of smooth portions on the innersphere surface wherein the plurality of smooth portions and the plurality of pyramidal projections cover the entire innersphere surface. 
     A further aspect of the present invention is a non-dimpled golf ball having a sphere and a plurality of pyramidal projections. The sphere has a diameter in the range of 1.60 to 1.70. The plurality of pyramidal projections extend outward from the sphere. Each of the projections has an apex that extends from a surface of the sphere in a range of 0.005 to 0.015. The entire surface of the golf ball is composed of the plurality of pyramidal projections and a plurality of smooth portions. 
    
    
     Having briefly described the present invention, the above and further objects, features and advantages thereof will be recognized by those skilled in the pertinent art from the following detailed description of the invention when taken in conjunction with the accompanying drawings. 
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     FIG. 1 is an equatorial view of a golf ball of the present invention. 
     FIG. 2 is a polar view of the golf ball of FIG.  1 . 
     FIG. 3 is an enlargement of a section of FIG.  1 . 
     FIG. 4 is a cross-sectional view of the surface of the golf ball of the present invention illustrating a phantom sphere. 
     FIG. 5 is a top plan view of a section of the golf ball of the present invention to illustrate the apex of each of the pyramidal projections. 
     FIG. 6 is an isolated cross-sectional view of one embodiment of pyramidal projections extending outward from the surface of the innersphere of the golf ball of the present invention. 
     FIG. 6A is an isolated top plan view of the pyramidal projection of FIG.  6 . 
     FIG. 6B is an isolated top plan view of an alternative embodiment of a pyramidal projection. 
     FIG. 7 is an enlarged view of the surface of a golf ball of the present invention to demonstrate the minimal volume feature of the present invention. 
     FIG. 8 is an enlarged view of the surface of a golf ball of the prior art for comparison to the minimal volume feature of the present invention. 
     FIG. 9 is a cross-sectional view of a solid three-piece golf ball with the surface geometry of the present invention. 
     FIG. 10 is a cross-sectional view of a solid two-piece golf ball with the surface geometry of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in FIGS. 1-3, a golf ball is generally designated  20 . The golf ball maybe a two-piece golf ball, a three-piece golf ball, or a multiple layer golf ball. Further, the three-piece golf ball may have a wound layer, or a solid boundary layer. Additionally, the core of the golf ball  20  may be solid, hollow or filled with a fluid such as a gas or liquid. The cover of the golf ball  20  may be any suitable material. A preferred cover is composed of a thermosetting polyurethane material. An alternative cover  20  is composed of a blend of ionomers. However, those skilled in the pertinent art will recognize that other cover materials may be utilized without departing from the scope and spirit of the present invention. The golf ball  20  may have a finish of a basecoat and/or top coat. 
     The golf ball  20  has a sphere  21  with an innersphere surface  22 . The golf ball  20  also has an equator  24  dividing the golf ball  20  into a first hemisphere  26  and a second hemisphere  28 . A first pole  30  is located ninety degrees along a longitudinal arc from the equator  24  in the first hemisphere  26 . A second pole  32  is located ninety degrees along a longitudinal arc from the equator  24  in the second hemisphere  28 . 
     Extending outward from the surface  22  of the innersphere  21  are a plurality of projections  40 . In a preferred embodiment, the projections  40  are pyramidal projections. However, those skilled in the pertinent art will recognize that the projections  40  may have other similar shapes. The projections are connected to each other to form a unique pattern on the surface  22  of the innersphere  21 . The apices  50  are the congruence of three sides  51   a,    51   b  and  51   c  of the pyramidal structure. 
     Unlike traditional golf balls that attempt to minimize the land area (the non-dimpled area) by packing in various sizes of dimples, the preferred embodiment of the present invention has zero land area since only a line of each of the plurality of projections  40  is in a spherical plane at 1.68 inches. More specifically, the land area of traditional golf balls is the area forming a sphere of at least 1.68 inches for USGA and R&amp;A conforming golf balls. This land area is minimized with dimples that are concave into the surface of the sphere of the traditional golf ball. However, the innersphere  21  of the golf ball  20  of the present invention has a diameter that is less than 1.68 inches. The golf ball  20  of the present invention conforms to the USGA and R&amp;A 1.68 inches diameter requirement due to the height of the projections  40  from the surface  22  of the innersphere  21 . The height of the projections  40  are such that the diameter of the golf ball  20  of the present invention meets or exceeds the 1.68 inches requirement. In a preferred embodiment, only a point at the apex of each of the projections  40  meets the 1.68 inches requirement. 
     Traditional golf balls were designed to have the dimples “trip” the boundary layer on the surface of a golf ball in flight to create a turbulent flow for greater lift and reduced drag. The golf ball  20  of the present invention has the plurality of projections  40  to trip the boundary layer of air about the surface of the golf ball  20  in flight. 
     As shown in FIG. 4, a phantom 1.68 inches sphere, as shown by dashed line  45 , encompasses the projections  40  and the innersphere  21 . The volume of the projections  40  as measured from the surface  22  of the innersphere to the apex  50  is a minimal amount of the volume between the phantom 1.68 inches sphere and the innersphere  21 . In the preferred embodiment, the apex  50  lies on the phantom 1.68 inches sphere. Thus, over 99 percent, and closer to 99.5 percent, of the entire surface of the golf ball  20  lies below the 1.68 inches phantom sphere. 
     As shown in FIG. 5, the width of each of the apices  50  is minimal since the apex is a point. In theory, the width of each apex  50  should approach the width of a point. In practice, the width of each apex  50  of each projection  40  is determined by the precision of the mold utilized to produce the golf ball  20 . The precision of the mold is itself determined by the master used to form the mold. In the practice, the width of each line ranges from 0.0001 inch to 0.001 inch. 
     AS shown in FIGS. 6 and 6A, the radius R ball  of the inner sphere is preferably in the range of 0.825 inch to 0.840 inch, and most preferably 0.831 inch. The radius R p  of the sides  51   a,    51   b  and  51   c  of each of the pyramidal projections is preferably in the range of 0.150 inch to 0.600 inch, more preferably 0.200 inch to 0.400 inch, and most preferably 0.250 inch. Each of the pyramidal projections  40  have three edge points  52   a,    52   b  and  52   c  with the edge between each of the points  52   a-c  curved and equal to each other edge. Each side  51   a-c  is concave from the edge to the apex  50 . In an alternative embodiment as shown in FIG. 6B, there are six sides  53   a-f  meeting at an apex  50 ′. Those skilled in the art will recognize that the pyramidal projections  40  may have a greater number of sides without departing from the scope and spirit of the present invention. 
     In an alternative embodiment, not shown, the golf ball  20  has a parting line  100  that is non-planar allowing for some of the plurality of pyramidal projections  40  to be disposed about the equator  24 . The parting line  100  will alternate along edge points  51   a-c  of pyramidal projections  40 . Such a golf ball  20  is fabricated using a mold such as disclosed in co-pending U.S. patent application Ser. No. 09/442,845, filed on Nov. 18, 1999, entitled Mold For A Golf Ball, and which is hereby incorporated herein by reference. This embodiment allows for greater uniformity of the pyramidal projections. 
     FIG. 7 is an enlarged view of the surface of the golf ball  20  of the present invention to demonstrate the minimal volume of the golf ball  20  from a predetermined distance from the greatest extent of the golf ball  20 . More specifically, the greatest extent of one embodiment of the golf ball  20  are the apices  50  of the projections  40  which lie on a spherical plane (shown as dashed line  45 ) which has a 1.682 inches diameter. Those skilled in the art should recognize that other embodiments could have the apices  50  lie on a spherical plane at 1.70 inches, 1.72 inches, 1.64 inches, 1.60 inches, or any other variation in the diameter of the greatest extent of the golf ball  20 . Having defined the greatest extent of the golf ball  20 , the present invention will have a minimal volume from this greatest extent toward the innersphere  21 . For example, dashed line  130  represents a spherical plane that intersects each of the projections  40  at a distance of 0.002 inch from the greatest extent of the golf ball  20 . The volume of the golf ball  20  of the present invention between the greatest extent spherical plane  45  and the spherical plane  130  is only 0.0000667744 cubic inch. In other words, the outermost 0.002 inch of the golf ball  20  has a volume 0.0000667744 cubic inch. 
     FIG. 8 illustrates the surface of a golf ball  140  of the prior art that has traditional dimples  142  encompassed by a land area  144 . The land area  144  represents the greatest extent of the golf ball  140  of the prior art. For comparison to the golf ball  20  of the present invention, the volume of a high dimple coverage (&gt;80%) golf ball  140  of the prior art between the greatest extent  144  and a spherical plane  130 ′ is 0.00213 cubic inch. The total volume of the outermost 0.002 inch of all of the plurality of pyramidal projections  40  of the golf ball  20  of the present invention is less than 0.00213 cubic inch. Spherical planes  132 ,  134  and  136 , at 0.004 inch, 0.006 inch and 0.008 inch respectively, will have volumes of 0.00028248 cubic inch, 0.000655512 cubic inch and 0.00124696 cubic inch on the golf ball  20  of the present invention. While spherical planes  132 ′,  134 ′ and  136 ′, at 0.004 inch, 0.006 inch and 0.008 inch respectively, will have volumes of 0.00498 cubic inch, 0.00841 cubic inch and 0.01238 cubic inch on the golf ball  140  of the prior art  140 . 
     Thus, a golf ball  20  of the present invention will have a minimal volume at a predetermined distance from the greatest extent of the golf ball  20 . This minimal volume is a minimal amount necessary to trip the boundary layer air at low speed while providing a low drag level at high speeds. Table One and Table Two 
     
       
         
               
               
               
               
             
           
               
                 TABLE ONE 
               
               
                   
               
               
                 Shell Delta 
                   
                 Number of 
                 Volume/tot 
               
               
                 Dia. 
                 Volume-Lay1, 1 Delt 
                 lay1 delt 
                 lay1 
               
               
                   
               
             
             
               
                 0.001 
                 2.75E−08 
                 352 
                 0.00000968 
               
               
                 0.002 
                 0.000000118 
                 352 
                 0.000041536 
               
               
                 0.003 
                 2.243E−07 
                 352 
                 7.89536E−05 
               
               
                 0.004 
                 0.000000426 
                 352 
                 0.000149952 
               
               
                 0.005 
                 0.000000685 
                 352 
                 0.00024112 
               
               
                 0.006 
                 0.00000114 
                 352 
                 0.00040128 
               
               
                 0.007 
                 0.00000151 
                 352 
                 0.00053152 
               
               
                 0.008 
                 0.00000211 
                 352 
                 0.00074272 
               
               
                 0.009 
                 0.00000296 
                 352 
                 0.00104192 
               
               
                   
               
             
          
         
       
     
     
       
         
               
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                 Shell 
                   
                   
                   
                   
               
               
                 Delta 
                 Volume-Lay2, 
                 Number of 
                   
                 Total 
               
               
                 Dia. 
                 1 delt 
                 lay2delt 
                 Volume/tot lay2 
                 Resulting Volume 
               
               
                   
               
             
             
               
                 0.001 
                 1.79E − 08 
                 264 
                  4.7256E − 06 
                 1.44056E − 05 
               
               
                 0.002 
                 9.56E − 08 
                 264 
                 2.52384E − 05 
                 6.67744E − 05 
               
               
                 0.003 
                 0.000000221 
                 264 
                 0.000058344 
                 0.000137298 
               
               
                 0.004 
                 0.000000502 
                 264 
                 0.000132528 
                 0.00028248  
               
               
                 0.005 
                 0.000000648 
                 264 
                 0.000171072 
                 0.000412192 
               
               
                 0.006 
                 0.000000963 
                 264 
                 0.000254232 
                 0.000655512 
               
               
                 0.007 
                 0.00000139  
                 264 
                 0.00036696  
                 0.00089848  
               
               
                 0.008 
                 0.00000191  
                 264 
                 0.00050424  
                 0.00124696  
               
               
                 0.009 
                 0.00000261  
                 264 
                 0.00068904  
                 0.00173096  
               
               
                   
               
             
          
         
       
     
     The plurality of pyramidal protrusions  40  preferably number from 200 to 400, 225 to 350, and most preferably 264. The plurality of pyramidal protrusions  40  cover from 60% to 90% of the surface  22  of the innersphere  21  of the golf ball  20 , more preferably from 70% to 85%, and most preferably 80%. The smooth portions of the surface  22  cover between 10% to 40% of the surface  22  of the innersphere  21 , more preferably 15% to 30%, and most preferably 20% of the surface  22  of the innersphere  21 . 
     In a preferred embodiment, the golf ball  20  is a solid three-piece golf ball as shown in FIG.  9 . The golf ball  20  includes a solid core  75 , an intermediate layer  85  and a cover  95 . The solid core  75  is preferably composed of a polybutadiene material, and the core  75  has a diameter between 1.30 inches and 1.55 inches. The core  75  preferably has a PGA compression ranging from 50 to 110 points, more preferably from 60 points to 100 points, and most preferably 80 points. The intermediate layer  85  is preferably composed of a blend of ionomers, and is preferably injection molded over the core  75 . The intermediate layer preferably has a thickness from 0.040 inch to 0.080 inch, and a Shore D hardness of between 60 to 75, as measured according to ASTM D-2240. The cover  95  is preferably composed of a thermosetting polyurethane material, and preferably has a thickness of between 0.020 inch to 0.040 inch. The cover  95  preferably has a Shore D hardness ranging from 30 to 65, as measured according to ASTM D-2240. The cover  95  is preferably cast over the intermediate layer  85  and the core  75 . The surface geometry pattern of the present invention is preferably imparted on the cover  95  during the casting process. 
     In an alternative embodiment, the golf ball  20  is a two-piece golf ball as shown in FIG.  10 . The golf ball  20  includes a solid core  75   a  and a cover  95   a.  The solid core  75   a  is preferably composed of a polybutadiene material, and the core  75  has a diameter between 1.40 inches and 1.60 inches. The core  75   a  preferably has a PGA compression ranging from 50 to 110 points, more preferably from 60 points to 100 points, and most preferably 80 points. The cover  95   a  is preferably composed of a blend of ionomers, and is preferably injection molded over the core  75   a.  The cover  95   a  preferably has a thickness from 0.040 inch to 0.10 inch, and a Shore D hardness of between 60 to 75, as measured according to ASTM D-2240. The surface geometry pattern of the present invention is preferably imparted on the cover  95   a  during the injection molding process. 
     During finishing of the golf ball  20  of the present invention, the surface  22  of the innersphere  21  may be painted one color (or unpainted) while the plurality of pyramidal protrusions  40  are painted a different distinctive color. For example, the surface  22  may be painted white while the plurality of pyramidal protrusions  40  are painted black, or only the apices  50  are painted black. Those skilled in the pertinent art will recognize that other color combinations may be used without departing from the scope and spirit of the present invention. 
     From the foregoing it is believed that those skilled in the pertinent art will recognize the meritorious advancement of this invention and will readily understand that while the present invention has been described in association with a preferred embodiment thereof, and other embodiments illustrated in the accompanying drawings, numerous changes, modifications and substitutions of equivalents may be made therein without departing from the spirit and scope of this invention which is intended to be unlimited by the foregoing except as may appear in the following appended claims. Therefore, the embodiments of the invention in which an exclusive property or privilege is claimed are defined in the following appended claims.