Golf club head

Abstract

A golf club head includes a face portion including a striking face, a crown portion including a crown surface, a sole portion including a sole surface, and a hosel portion including a protruding portion that protrudes from the crown surface. The hosel portion includes a single upper end surface that is a substantially flat surface, and a plurality of shaft receiving holes formed on the upper end surface. The shaft receiving holes include a first shaft receiving hole and a second shaft receiving hole. The golf club head also includes a cover member that covers at least one of the shaft receiving holes which is not to have a shaft inserted.

What is claimed is: 
     
         1 . A golf club head comprising:
 a face portion including a striking face,   a crown portion including a crown surface,   a sole portion including a sole surface, and   a hosel portion including a protruding portion that protrudes from the crown surface, wherein   the hosel portion includes a single upper end surface that is a substantially flat surface, and a plurality of shaft receiving holes formed on the upper end surface,   the shaft receiving holes include a first shaft receiving hole and a second shaft receiving hole, and   the golf club head further includes a cover member that covers at least one of the shaft receiving holes which is not to have a shaft inserted.   
     
     
         2 . The golf club head according to  claim 1 , wherein the first shaft receiving hole is located on a face side relative to the second shaft receiving hole. 
     
     
         3 . The golf club head according to  claim 2 , wherein a center line of the second shaft receiving hole is inclined toward the face side compared to a center line of the first shaft receiving hole. 
     
     
         4 . The golf club head according to  claim 2 , wherein a center line of the second shaft receiving hole is inclined toward a toe side compared to a center line of the first shaft receiving hole. 
     
     
         5 . The golf club head according to  claim 1 , wherein
 the shaft receiving holes each have a stepped portion in a vicinity of the upper end surface, and   the golf club head is configured such that a sleeve attached to a tip portion of the shaft is fixed to the hosel portion while engaging with the stepped portion of one of the shaft receiving holes.   
     
     
         6 . The golf club head according to  claim 1 , wherein the upper end surface of the hosel portion extends along a heel-side contour of the crown surface. 
     
     
         7 . The golf club head according to  claim 6 , wherein
 the golf club head further includes a crown contour protruding portion that extends along the heel-side contour of the crown surface from the upper end surface of the hosel portion toward a back side.   
     
     
         8 . The golf club head according to  claim 1 , wherein the upper end surface has a radius of curvature in a cross section of greater than or equal to 152 mm. 
     
     
         9 . The golf club head according to  claim 1 , wherein the upper end surface includes an opening line of the first shaft receiving hole, an opening line of the second shaft receiving hole, and a part located between the first shaft receiving hole and the second shaft receiving hole. 
     
     
         10 . The golf club head according to  claim 1 , wherein
 the cover member includes a fixed portion having a through hole, and a cover portion that covers at least one of the shaft receiving holes which is not to have the shaft inserted,   when the shaft is inserted into the first shaft receiving hole, the fixed portion is fixed to the first shaft receiving hole, and the cover portion covers the second shaft receiving hole, and   when the shaft is inserted into the second shaft receiving hole, the fixed portion is fixed to the second shaft receiving hole and the cover portion covers the first shaft receiving hole.   
     
     
         11 . The golf club head according to  claim 2 , wherein
 a distance in a face-back direction between a center of the first shaft receiving hole and a center of the second shaft receiving hole is greater than or equal to 15 mm and less than or equal to 25 mm.   
     
     
         12 . A golf club head comprising:
 a face portion including a striking face,   a crown portion including a crown surface,   a sole portion including a sole surface, and   a hosel portion including a protruding portion that protrudes from the crown surface, wherein   the hosel portion includes a first shaft receiving hole and a second shaft receiving hole, and   the golf club head further includes a cover member that covers either the first shaft receiving hole or the second shaft receiving hole which is not to have a shaft inserted.   
     
     
         13 . The golf club head according to  claim 12 , wherein the first shaft receiving hole is located on a face side relative to the second shaft receiving hole. 
     
     
         14 . The golf club head according to  claim 13 , wherein a center line of the second shaft receiving hole is inclined toward the face side compared to a center line of the first shaft receiving hole. 
     
     
         15 . The golf club head according to  claim 13 , wherein a center line of the second shaft receiving hole is inclined toward a toe side compared to a center line of the first shaft receiving hole. 
     
     
         16 . The golf club head according to  claim 12 , wherein
 the cover member includes a fixed portion having a through hole, and a cover portion that covers either the first shaft receiving hole or the second shaft receiving hole which is not to have the shaft inserted,   when the shaft is inserted into the first shaft receiving hole, the fixed portion is fixed to the first shaft receiving hole, and the cover portion covers the second shaft receiving hole, and   when the shaft is inserted into the second shaft receiving hole, the fixed portion is fixed to the second shaft receiving hole and the cover portion covers the first shaft receiving hole.   
     
     
         17 . The golf club head according to  claim 13 , wherein
 a distance in a face-back direction between a center of the first shaft receiving hole and a center of the second shaft receiving hole is greater than or equal to 15 mm and less than or equal to 25 mm.