Golf club head

Abstract

An iron-type golf club head is disclosed having a heel portion, a sole portion, a toe portion, a top-line portion, a front portion, a rear portion, and a striking face. A back wall is also disclosed in the rear portion enclosing a portion of the rear portion to create an enclosed cavity. The cavity is defined by at least a rear surface of the striking face, an inner back wall surface, and the sole portion. A plug and a filler material is located within the enclosed cavity. The filler material surrounds the plug and is configured to hold the plug in place. The plug is lighter than the filler material.

We claim: 
     
       1. A hollow iron-type golf club head comprising:
 a heel portion, a sole portion, a toe portion, a top-line portion, a front portion, a rear portion, and a striking face having an unsupported face area of between about 300 mm 2  to about 4,000 mm 2 ;   a back wall in the rear portion enclosing a substantial portion of the rear portion to create a substantially enclosed cavity, the enclosed cavity being defined by at least a rear surface of the striking face, an inner back wall surface, and the sole portion,   at least one plug located within the enclosed cavity, the at least one plug being compressed between the rear surface of the striking face and the back wall in the rear portion;   a filler material located within the enclosed cavity, the filler material substantially surrounding the at least one plug and being configured to hold the at least one plug in place, the golf club head defining an aperture into the enclosed cavity, the aperture being configured to allow the cavity to be filled with the filler material;   wherein the unsupported face area includes a thickened central region;   wherein the at least one plug is positioned to be in contact with at least a portion of the thickened central region; and   wherein the at least one plug occupies less than 20% of the total club head cavity volume in the enclosed cavity.   
     
     
       2. The iron-type golf club head of  claim 1 , wherein the enclosed cavity has a volume between about 1 cc and 200 cc. 
     
     
       3. The iron-type golf club head of  claim 1 , wherein the enclosed cavity has a volume between about 10 cc and 20 cc. 
     
     
       4. The iron-type golf club head of  claim 1 , wherein the at least one plug has a volume between about 0.1 cc and about 1 cc. 
     
     
       5. The iron-type golf club head of  claim 1 , wherein the at least one plug occupies between about 1% to about 10% of the total club head cavity volume in the enclosed cavity. 
     
     
       6. The iron-type golf club head of  claim 1 , wherein the at least one plug occupies between about 0.5% to about 5% of the total club head cavity volume in the enclosed cavity. 
     
     
       7. The iron-type golf club head of  claim 1 , wherein the filler material is an expanding foam material having a density between about 0.03 g/cc and about 0.19 g/cc. 
     
     
       8. The iron-type golf club head of  claim 1 , wherein the filler material occupies about 50% to about 99% of the total club head cavity volume in the enclosed cavity. 
     
     
       9. The iron-type golf club head of  claim 1 , wherein the back wall includes at least a first aperture, the first aperture being configured to allow the at least one plug to be inserted into the first aperture and is configured to allow the at least one plug to move from a first position to a second position. 
     
     
       10. The iron-type golf club head of  claim 9 , wherein the back wall includes at least one slot, the at least one slot being connected to the first aperture and is configured to secure the at least one plug. 
     
     
       11. A hollow iron-type golf club head comprising:
 a heel portion, a sole portion, a toe portion, a top-line portion, a front portion, a rear portion, and a striking face having an unsupported face area of between about 300 mm 2  to about 4,000 mm 2 ;   a back wall in the rear portion enclosing a substantial portion of the rear portion to create a substantially enclosed cavity, the enclosed cavity being defined by at least a rear surface of the striking face, an inner back wall surface, and the sole portion;   at least one plug located within the enclosed cavity, the at least one plug being compressed between the rear surface of the striking face and the back wall in the rear portion;   wherein the at least one plug occupies less than 20% of the total club head cavity volume in the enclosed cavity, and   wherein the back wall includes at least a first aperture, the first aperture being configured to allow the at least one plug to be inserted into the first aperture and being configured to allow the at least one plug to move from a first position to a second position.   
     
     
       12. The iron-type golf club head of  claim 11 , wherein the enclosed cavity has a volume between about 1 cc and 200 cc. 
     
     
       13. The iron-type golf club head of  claim 11 , wherein the enclosed cavity has a volume between about 10 cc and 20 cc. 
     
     
       14. The iron-type golf club head of  claim 11 , wherein the at least one plug has a volume between about 0.1 cc and about 1 cc. 
     
     
       15. The iron-type golf club head of  claim 11 , wherein the at least one plug occupies between about 1% to about 10% of the total club head cavity volume in the enclosed cavity. 
     
     
       16. The iron-type golf club head of  claim 11 , wherein the at least one plug occupies between about 0.5% to about 5% of the total club head cavity volume in the enclosed cavity. 
     
     
       17. The iron-type golf club head of  claim 11 , further comprising a filler material located within the enclosed cavity, the filler material substantially surrounding the at least one plug and being configured to hold the at least one plug in place. 
     
     
       18. The iron-type golf club head of  claim 17 , wherein the filler material is an expanding foam material having a density between about 0.03 g/cc and about 0.19 g/cc. 
     
     
       19. The iron-type golf club head of  claim 17 , wherein the filler material occupies about 50% to about 99% of the total club head cavity volume in the enclosed cavity. 
     
     
       20. The iron-type golf club head of  claim 17 , wherein the filler material completely fills a remaining cavity volume around the at least one plug. 
     
     
       21. The iron-type golf club head of  claim 11 , wherein the coefficient of restitution of the club is greater than about 0.8. 
     
     
       22. The iron-type golf club head of  claim 11 , wherein the back wall includes at least one slot, the at least one slot being connected to the first aperture and is configured to secure the at least one plug. 
     
     
       23. An iron-type golf club head comprising:
 a body having a heel portion, a toe portion, a top-line portion, a sole portion, a striking face joining the top-line portion to the sole portion, and a rear portion joined to the striking face by the sole portion;   a badge attached to the body;   a polymeric plug in contact with a rear surface of the striking face and a portion of the body;   wherein the rear portion extends upward from the sole portion toward the top-line portion to create an enclosed cavity bounded at least in part by a portion of the rear portion, a portion of the sole portion, a portion of the striking face, and a portion of the badge, wherein the enclosed cavity has a cavity volume;   wherein a first portion of the sole portion, located closer to the striking face than the rear portion, and bounding the enclosed cavity has a first portion sole thickness of less than 3 mm;   wherein the top-line portion has a total top line thickness of less than 9 mm;   wherein a portion of striking face has a face thickness of less than 2.5 mm;   wherein (a) the striking face has a center point, (b) an upper portion of the enclosed cavity is located at an elevation above the center point and has an upper portion cavity depth measured from an interior surface of the striking face to an interior surface of the enclosed cavity in a direction perpendicular to an exterior surface of the striking face, (c) a lower portion of the enclosed cavity is located at an elevation below the center point and has a lower portion cavity depth measured from the interior surface of the striking face to the interior surface of the enclosed cavity in a direction perpendicular to the exterior surface of the striking face, and (d) the enclosed cavity has a cavity depth measured from the interior surface of the striking face to the interior surface of the enclosed cavity in a direction perpendicular to the exterior surface of the striking face, and the cavity depth varies;   wherein at least a portion of the polymeric plug is located in the upper portion;   wherein the striking face has an unsupported face surface area within a range of between 450 mm 2  to 3500 mm 2 ; and   wherein the club head has a center of gravity located at an elevation between 12 mm and 25 mm above the ground plane.    
     
     
       24. The iron-type golf club head of  claim 23 , wherein the total top line thickness is less than 8.5 mm, the polymeric plug has a density of less than 1.75 g/cc, and at least one weighting element is attached to the body portion.  
     
     
       25. The iron-type golf club head of  claim 24 , wherein the polymeric plug has a plug volume that is no more than 20% of the cavity volume.  
     
     
       26. The iron-type golf club head of  claim 25 , wherein the polymeric plug occupies between 1% to 10% of the cavity volume.  
     
     
       27. The iron-type golf club head of  claim 24 , wherein the first portion sole thickness is less than 2 mm.  
     
     
       28. The iron-type golf club head of  claim 27 , wherein the unsupported face surface area is less than 3260 mm 2 , and the face thickness of a portion of striking face is less than 2 mm.  
     
     
       29. The iron-type golf club head of  claim 28 , wherein the polymeric plug has a shore D hardness of 40 or less.  
     
     
       30. The iron-type golf club head of  claim 29 , wherein the polymeric plug has a shore A hardness of 10-70.  
     
     
       31. The iron-type golf club head of  claim 29 , wherein the polymeric plug density is at least 0.95 g/cc.  
     
     
       32. The iron-type golf club head of  claim 29 , wherein the unsupported face surface area is less than 3175 mm 2 , and a coefficient of restitution of the club head is greater than 0.79.  
     
     
       33. The iron-type golf club head of  claim 32 , wherein the unsupported face surface area is greater than 2000 mm 2 .  
     
     
       34. The iron-type golf club head of  claim 29 , wherein the cavity volume is 20 cc or less.  
     
     
       35. The iron-type golf club head of  claim 34 , wherein the cavity volume is at least 10 cc, and a coefficient of restitution of the club head is greater than 0.79.  
     
     
       36. The iron-type golf club head of  claim 29 , wherein the polymeric plug has a mass of less than 1 g.  
     
     
       37. The iron-type golf club head of  claim 29 , wherein the badge covers the polymeric plug and the portion of the body in contact with the polymeric plug.  
     
     
       38. The iron-type golf club head of  claim 29 , wherein the lower portion cavity depth is different at two elevations above the ground plane, and the enclosed cavity extends to the top-line portion.  
     
     
       39. The iron-type golf club head of  claim 38 , wherein the upper portion cavity depth is different at two elevations above the ground plane.  
     
     
       40. The iron-type golf club head of  claim 38 , wherein the badge has a badge thickness that varies.  
     
     
       41. The iron-type golf club head of  claim 40 , wherein the badge has a ridge that extends from a heel side to a toe side.  
     
     
       42. The iron-type golf club head of  claim 29 , wherein the polymeric plug has a face contact surface in contact with the rear surface of the striking face, and the face contact surface is circular.  
     
     
       43. The iron-type golf club head of  claim 42 , wherein the polymeric plug has a tapering sidewall.  
     
     
       44. The iron-type golf club head of  claim 28 , wherein the striking face comprises a striking plate welded to a portion of the heel portion, a portion of the toe portion, and a portion of the top-line portion, with the striking plate formed of a striking plate material different than a material forming a portion of the sole portion.  
     
     
       45. The iron-type golf club head of  claim 44 , wherein the striking plate material comprises carbon steel, and the total top line thickness is at least 6 mm.  
     
     
       46. The iron-type golf club head of  claim 45 , wherein the striking face thickness varies, and a coefficient of restitution of the club head is greater than 0.79.  
     
     
       47. The iron-type golf club head of  claim 46 , wherein at least a portion of the polymeric plug is located in the lower portion.  
     
     
       48. The iron-type golf club head of  claim 46 , wherein the coefficient of restitution of the club head is greater than 0.8.  
     
     
       49. The iron-type golf club head of  claim 46 , wherein a portion of the heel portion, a portion of the toe portion, a portion of the top-line portion, and at least a portion of the sole portion are formed of 17-4 stainless steel.  
     
     
       50. The iron-type golf club head of  claim 46 , further including a filler material is located within the enclosed cavity and in contact with the polymeric plug.  
     
     
       51. The iron-type golf club head of  claim 46 , wherein the rear portion includes a back wall surface extending upward from the rear portion to the top-line portion, the polymeric plug contacts the back wall surface and the rear surface of the striking face, at least a portion of the back wall surface is separated from the toe portion by a toe hole, at least a portion of the back wall surface is separated from the heel portion by a heel hole, and the badge covers the polymeric plug, the back wall surface, the toe hole, and the heel hole.  
     
     
       52. The iron-type golf club head of  claim 51 , wherein the polymeric plug has a face contact surface in contact with the rear surface of the striking face, and the face contact surface is circular.  
     
     
       53. The iron-type golf club head of  claim 52 , wherein the polymeric plug has a tapering sidewall.  
     
     
       54. An iron-type golf club head comprising:
 a body having a heel portion, a toe portion, a top-line portion, a sole portion, a striking face joining the top-line portion to the sole portion, and a rear portion joined to the striking face by the sole portion;   a badge attached to the body;   a polymeric plug in contact with a rear surface of the striking face and a portion of the body;   at least one weighting element is attached to the body portion;   wherein the rear portion extends upward from the sole portion toward the top-line portion to create an enclosed cavity bounded at least in part by a portion of the rear portion, a portion of the sole portion, a portion of the striking face, and a portion of the badge, wherein the enclosed cavity has a cavity volume;   wherein a first portion of the sole portion, located closer to the striking face than the rear portion, and bounding the enclosed cavity has a first portion sole thickness of less than 3 mm;   wherein the top-line portion has a total top line thickness of less than 9 mm;   wherein a portion of striking face has a face thickness of less than 2.0 mm;   wherein (a) the striking face has a center point, (b) an upper portion of the enclosed cavity is located at an elevation above the center point and has an upper portion cavity depth measured from an interior surface of the striking face to an interior surface of the enclosed cavity in a direction perpendicular to an exterior surface of the striking face, (c) a lower portion of the enclosed cavity is located at an elevation below the center point and has a lower portion cavity depth measured from the interior surface of the striking face to the interior surface of the enclosed cavity in a direction perpendicular to the exterior surface of the striking face, and (d) the enclosed cavity has a cavity depth measured from the interior surface of the striking face to the interior surface of the enclosed cavity in a direction perpendicular to the exterior surface of the striking face, and the cavity depth varies;   wherein at least a portion of the polymeric plug is located in the upper portion;   wherein the striking face has an unsupported face surface area within a range of between 450 mm 2  to 3500 mm 2 ;   wherein the club head has a center of gravity located at an elevation between 12 mm and 25 mm above the ground plane; and   wherein a coefficient of restitution of the club head is greater than 0.79.    
     
     
       55. The iron-type golf club head of  claim 54 , wherein the badge covers the polymeric plug and the portion of the body in contact with the polymeric plug, and the enclosed cavity extends to the top-line portion.  
     
     
       56. The iron-type golf club head of  claim 55 , wherein the total top line thickness is less than 8.5 mm, and the cavity volume is 20 cc or less.  
     
     
       57. The iron-type golf club head of  claim 56 , wherein the polymeric plug has a shore D hardness of 40 or less.  
     
     
       58. The iron-type golf club head of  claim 57 , wherein the first portion sole thickness is less than 2 mm.  
     
     
       59. The iron-type golf club head of  claim 58 , wherein the cavity volume is at least 10 cc, and the lower portion cavity depth is different at two elevations above the ground plane, the upper portion cavity depth is different at two elevations above the ground plane, and the badge has a badge thickness that varies.  
     
     
       60. The iron-type golf club head of  claim 59 , wherein the badge has a plurality of ridges that intersect.  
     
     
       61. The iron-type golf club head of  claim 59 , wherein the polymeric plug has a plug volume that is no more than 20% of the cavity volume.  
     
     
       62. The iron-type golf club head of  claim 61 , wherein the polymeric plug occupies between 1% to 10% of the cavity volume.  
     
     
       63. The iron-type golf club head of  claim 59 , wherein the polymeric plug has a shore A hardness of 10-70, the badge has a badge thickness that varies, and the polymeric plug has a density of less than 1.75 g/cc.  
     
     
       64. The iron-type golf club head of  claim 58 , wherein the polymeric plug has a face contact surface in contact with the rear surface of the striking face, and the face contact surface is circular.  
     
     
       65. The iron-type golf club head of  claim 58 , wherein the polymeric plug has a tapering sidewall.  
     
     
       66. The iron-type golf club head of  claim 58 , wherein the striking face comprises a striking plate welded to a portion of the heel portion, a portion of the toe portion, and a portion of the top-line portion, with the striking plate formed of a striking plate material different than a material forming a portion of the sole portion.  
     
     
       67. The iron-type golf club head of  claim 66 , wherein at least a portion of the polymeric plug is located in the lower portion.  
     
     
       68. The iron-type golf club head of  claim 66 , wherein the coefficient of restitution of the club head is greater than 0.8.  
     
     
       69. The iron-type golf club head of  claim 66 , wherein the rear portion includes a back wall surface extending upward from the rear portion to the top-line portion, the polymeric plug contacts the back wall surface and the rear surface of the striking face, at least a portion of the back wall surface is separated from the toe portion by a toe hole, at least a portion of the back wall surface is separated from the heel portion by a heel hole, and the badge covers the polymeric plug, the back wall surface, the toe hole, and the heel hole.  
     
     
       70. The iron-type golf club head of  claim 69 , wherein the at least one weighting element includes at least two weighting elements, and the polymeric plug has a face contact surface in contact with the rear surface of the striking face, and the face contact surface is circular.  
     
     
       71. The iron-type golf club head of  claim 70 , wherein the polymeric plug has a tapering sidewall.  
     
     
       72. An iron-type golf club head comprising:
 a body having a heel portion, a toe portion, a top-line portion, a sole portion, a striking face joining the top-line portion to the sole portion, and a rear portion joined to the striking face by the sole portion;   a badge attached to the body;   a polymeric plug in contact with a rear surface of the striking face and a portion of the body;   wherein the rear portion extends upward from the sole portion toward the top-line portion to create an enclosed cavity bounded at least in part by a portion of the rear portion, a portion of the sole portion, a portion of the striking face, and a portion of the badge, wherein the enclosed cavity has a cavity volume;   wherein a first portion of the sole portion, located closer to the striking face than the rear portion, and bounding the enclosed cavity has a first portion sole thickness of less than 3 mm;   wherein the top-line portion has a total top line thickness of less than 9 mm;   wherein a portion of striking face has a face thickness of less than 2.5 mm;   wherein (a) the striking face has a center point, (b) an upper portion of the enclosed cavity is located at an elevation above the center point and has an upper portion cavity depth measured from an interior surface of the striking face to an interior surface of the enclosed cavity in a direction perpendicular to an exterior surface of the striking face, (c) a lower portion of the enclosed cavity is located at an elevation below the center point and has a lower portion cavity depth measured from the interior surface of the striking face to the interior surface of the enclosed cavity in a direction perpendicular to the exterior surface of the striking face, and (d) the enclosed cavity has a cavity depth measured from the interior surface of the striking face to the interior surface of the enclosed cavity in a direction perpendicular to the exterior surface of the striking face, and the cavity depth varies;   wherein at least a portion of the polymeric plug is located in the upper portion;   wherein the striking face has an unsupported face surface area within a range of between 450 mm 2  to 3500 mm 2 ;   wherein the club head has a center of gravity located at an elevation between 12 mm and 25 mm above the ground plane; and   wherein the rear portion includes a back wall surface extending upward from the rear portion to the top-line portion, the polymeric plug contacts the back wall surface and the rear surface of the striking face, at least a portion of the back wall surface is separated from the toe portion by a toe hole, at least a portion of the back wall surface is separated from the heel portion by a heel hole, and the badge covers the polymeric plug, the back wall surface, the toe hole, and the heel hole.    
     
     
       73. The iron-type golf club head of  claim 72 , wherein the enclosed cavity extends to the top-line portion, the polymeric plug has a plug volume that is no more than 20% of the cavity volume, and the polymeric plug has a shore D hardness of 40 or less.  
     
     
       74. The iron-type golf club head of  claim 73 , wherein the cavity volume is at least 10 cc, and the badge has a badge thickness that varies.  
     
     
       75. The iron-type golf club head of  claim 74 , wherein a coefficient of restitution of the club head is greater than 0.79.  
     
     
       76. The iron-type golf club head of  claim 75 , wherein the first portion sole thickness is less than 2 mm.  
     
     
       77. The iron-type golf club head of  claim 75 , wherein the face thickness of a portion of striking face is less than 2 mm.  
     
     
       78. The iron-type golf club head of  claim 75 , wherein the polymeric plug has a density of less than 1.75 g/cc.  
     
     
       79. The iron-type golf club head of  claim 75 , wherein the unsupported face surface area is greater than 2000 mm 2 .  
     
     
       80. The iron-type golf club head of  claim 75 , wherein the cavity volume is 20 cc or less.  
     
     
       81. The iron-type golf club head of  claim 75 , wherein the lower portion cavity depth is different at two elevations above the ground plane, and the upper portion cavity depth is different at two elevations above the ground plane.  
     
     
       82. The iron-type golf club head of  claim 75 , wherein the striking face thickness varies, and the coefficient of restitution of the club head is greater than 0.8.  
     
     
       83. The iron-type golf club head of  claim 75 , wherein the striking face comprises a striking plate welded to a portion of the heel portion, a portion of the toe portion, and a portion of the top-line portion, with the striking plate formed of a striking plate material different than a material forming a portion of the sole portion, at least one weighting element is attached to the body portion, and at least a portion of the polymeric plug is located in the lower portion.  
     
     
       84. The iron-type golf club head of  claim 83 , wherein the coefficient of restitution of the club head is greater than 0.8, the at least one weighting element includes at least two weighting elements, and the face thickness of a portion of striking face is less than 2 mm.  
     
     
       85. The iron-type golf club head of  claim 84 , wherein the polymeric plug has a face contact surface in contact with the rear surface of the striking face, the face contact surface is circular, and the first portion sole thickness is less than 2 mm.  
     
     
       86. The iron-type golf club head of  claim 85 , wherein the polymeric plug has a tapering sidewall, and the badge has a plurality of ridges that intersect.