Golf club

Abstract

In a driver golf head ( 1 ) comprising a face ( 4 ) having a hitting surface, a sole ( 3 ) forming a lower portion, and a crown ( 5 ) forming an upper portion, the sole ( 3 ) is improved. The sole ( 3 ) in the position close to the face ( 4 ) was formed into an elastically deformable recess-projection shape, and part of the face ( 4 ) was formed into a projecting shape and integrated with the sole ( 3 ) to increase rigidity. Using a configuration with increased rigidity and decreased rigidity between the face ( 4 ) and sole to obtain an elastically deformable portion and providing a high-rigidity body ( 12 ) increased the repulsion force in the lower portion of the face ( 4 ) and extended the traveling distance of the golf ball.

What is claimed is:  
     
         1 . A golf club having a metallic hollow golf club head, said golf club comprising: 
 a face portion disposed at a front of said metallic hollow golf club head and having a hitting surface for hitting a golf ball; and    a body portion constituting a remaining part thereof,    said body portion comprising:    a sole forming a lower portion of said metallic hollow golf club head;    a crown forming an upper portion of said metallic hollow golf club head;    a toe forming a forepart of said metallic hollow golf club head;    a heel forming a rear part of said metallic hollow golf club head;    a back positioned opposite said face portion to form a back part of said metallic hollow golf club head; and    a hosel to which a shaft is connected, wherein    said golf club further comprises:    an elastically deformable portion which is formed in said body portion in the vicinity of the end portion of said face portion and has a structure that can be deformed elastically in response to said hitting; and    a high-rigidity portion which is disposed in said body portion on the side of said back of said elastically deformable portion for increasing the rigidity of said disposed portion.    
     
     
         2 . The golf club according to  claim 1 , wherein 
 said elastically deformable portion is disposed in an area where the lower portion of said face portion and said sole are joined; and    said high-rigidity portion is disposed in said sole for increasing the rigidity of said sole.    
     
     
         3 . The golf club according to  claim 1  or  2  , wherein 
 said high-rigidity portion is a high-rigidity body which is disposed in the form of a plurality of sections.  
 
     
     
         4 . The golf club according to  claim 2 , wherein 
 said elastically deformable portion includes the lower portion of said face portion that is bent at a bending angle of not less than 90 degrees to form a bent portion when said golf club is placed in an address state, and in a section taken along a vertical plane containing a line perpendicular to said hitting surface, said sole which is joined to this bent portion is convexly projected toward the upper portion of said metallic hollow golf club head.    
     
     
         5 . The golf club according to  claim 2 , wherein 
 said elastically deformable portion includes the lower portion of said face portion that is bent at a bending angle of not less than 90 degrees to form a bent portion when said golf club is placed in an address state, and in a section taken along a vertical plane containing a line perpendicular to said hitting surface, said sole which is joined to this bent portion is convexly projected toward said lower portion of said metallic hollow golf club head.    
     
     
         6 . The golf club according to  claim 2 , wherein 
 said elastically deformable portion includes the lower portion of said face portion that is bent at a bending angle of not less than 90 degrees to form a bent portion, and a plurality of holes are provided in said sole which is joined to the bent portion.    
     
     
         7 . The golf club according to  claim 2 , wherein 
 said elastically deformable portion includes the lower portion of said face portion that is bent at a bending angle of not less than 90 degrees to form a bent portion, and part of said sole which is joined to the bent portion is replaced with a thin plate.    
     
     
         8 . The golf club according to  claim 2 , wherein 
 said elastically deformable portion includes the lower portion of said face portion that is bent at a bending angle of not less than 90 degrees to form a bent portion, and part of said sole which is joined to the bent portion is divided into sections which are displaceable relative to each other.    
     
     
         9 . The golf club according to  claim 2 , wherein 
 in said elastically deformable portion, said sole has a smaller plate thickness than that of the bent portion.    
     
     
         10 . The golf club according to  claim 2 , wherein 
 a part of the sole in said elastically deformable portion forms an arch-shaped groove.    
     
     
         11 . The golf club according to  claim 2 , wherein 
 a part of the sole which is joined to the bent portion in said elastically deformable portion forms a groove having a surface approximately parallel to the hitting surface.    
     
     
         12 . The golf club according to  claim 9 , wherein 
 in said elastically deformable portion, the angle α of a gentle bend G formed by intersection of a line S 1  tangent to a surface of said face portion with a line S 2  tangent to said bent portion on the surface of said face portion is 90 degrees or larger, and the angle α 1  of a gentle bend H formed by intersection of said tangent line S 2  with a line S 3  tangent to a surface of said sole is 90 degrees or larger.    
     
     
         13 . The golf club according to  claim 12 , wherein 
 in said elastically deformable portion, at least one arch-shaped groove is provided in a surface of said sole in the vicinity of said bend H, and wherein the angle α 2  of a gentle bend J formed by intersection of a line S 4  tangent to said groove with said tangent line S 2  is 90 degrees or larger, the angle α 3  of a gentle bend K formed by intersection of a line S 5  tangent to said groove with said tangent line S 3  is 90 degrees or larger, and said bend G, said bend J, and said bend K form a continuous gently curved line.