Golf club head

Abstract

A golf club head has a hollow therein, and comprises a head main body including a face portion, a crown portion and a sole portion, and a weight member fixed to the head main body. The sole portion includes a toe side region, a heel side region and a center region therebetween. The center region is provided with a bulge portion which bulges downward than the outer surfaces of the toe side region and heel side region. The bulge portion has a bottom surface facing downward of the head, and a rear end surface extending upward from the bottom surface and facing toward the rear of the head. The rear end surface is provided with a recess into which the weight member is fixed so as to be located below the crown portion and above the bottom surface of the bulge portion.

1 . A golf club head with a hollow therein comprising:
 a head main body including a face portion, a crown portion and a sole portion; and   a weight member fixed to the head main body,   
       wherein
 in a reference state of the head in which the head is placed on a horizontal plane at a lie angle and loft angle specified for the head: 
 the sole portion includes a toe side region, a heel side region, and a center region between the toe side region and the heel side region; 
 the center region includes a bulge portion which bulges downward of the head from an outer surface of the toe side region and an outer surface of the heel side region, and extends in a front-rear direction of the head; 
 the bulge portion has a bottom surface facing downward of the head, and a rear end surface extending upward of the head from the bottom surface and facing rearward of the head, the rear end surface provided with a recess; and 
 the weight member is fixed to the recess so as to be located below the crown portion and above the bottom surface of the bulge portion. 
 
     
     
         2 . The golf club head according to  claim 1 , wherein
 in a top view of the head under the reference state, the center of gravity of the weight member is located between a first virtual straight line and a second virtual straight line, wherein the first virtual straight line is a straight line drawn rearward of the head from a face center while inclining to the toe at an angle of 15 degrees with respect to a normal line to the face passing through the face center, and the second virtual straight line is a straight line drawn rearward of the head from the face center while inclining to the heel at an angle of 15 degrees with respect to the normal line to the face passing through the face center.   
     
     
         3 . The golf club head according to  claim 2 , wherein
 in a top view of the head under the reference state, the weight member is located on a normal line to the face passing through the face center.   
     
     
         4 . The golf club head according to  claim 2 , wherein
 the recess has a bottom surface having a first depth,   the weight member is fixed so as to be in contact with the bottom surface of the recess,   a maximum thickness of the weight member from the bottom surface of the recess is smaller than the first depth.   
     
     
         5 . The golf club head according to  claim 3 , wherein
 the recess has a bottom surface having a first depth,   the weight member is fixed so as to be in contact with the bottom surface of the recess,   a maximum thickness of the weight member from the bottom surface of the recess is smaller than the first depth.   
     
     
         6 . The golf club head according to  claim 2 , wherein
 the weight member has a plate shape which defines a plate planar direction and a thickness direction, and   in a vertical cross-sectional view of the head taken in parallel with the front-rear direction of the head through the center of gravity of the weight member, the plate planar direction is arranged along the rear end surface.   
     
     
         7 . The golf club head according to  claim 3 , wherein
 the weight member has a plate shape which defines a plate planar direction and a thickness direction, and   in a vertical cross-sectional view of the head taken in parallel with the front-rear direction of the head through the center of gravity of the weight member, the plate planar direction is arranged along the rear end surface.   
     
     
         8 . The golf club head according to  claim 6 , wherein
 in a vertical cross-sectional view of the head taken in parallel with the front-rear direction of the head through the center of gravity of the weight member,   
       a maximum dimension of the weight member in the up-down direction is larger than a maximum dimension of the weight member in the front-rear direction. 
     
     
         9 . The golf club head according to  claim 7 , wherein
 in a vertical cross-sectional view of the head taken in parallel with the front-rear direction of the head through the center of gravity of the weight member,   
       a maximum dimension of the weight member in the up-down direction is larger than a maximum dimension of the weight member in the front-rear direction. 
     
     
         10 . The golf club head according to  claim 8 , wherein
 in the vertical cross-sectional view of the head, the weight member is arranged such that the plate planar direction is inclined backwardly from the lower side to the upper side at an angle θ.   
     
     
         11 . The golf club head according to  claim 9 , wherein
 in the vertical cross-sectional view of the head, the weight member is arranged such that the plate planar direction is inclined backwardly from the lower side to the upper side at an angle θ.   
     
     
         12 . The golf club head according to  claim 10 , wherein
 the angle θ is in a range from 10 to 30 degrees with respect to the up-down direction.   
     
     
         13 . The golf club head according to  claim 11 , wherein
 the angle θ is in a range from 10 to 30 degrees with respect to the up-down direction.   
     
     
         14 . The golf club head according to  claim 2 , wherein
 the center of gravity of the head is located below the face center, and   the center of gravity of the weight member is located below the center of gravity of the head.   
     
     
         15 . The golf club head according to  claim 3 , wherein
 the center of gravity of the head is located below the face center, and   the center of gravity of the weight member is located below the center of gravity of the head.   
     
     
         16 . The golf club head according to  claim 2 , wherein
 the volume of the head is in a range from 400 to 500 cc,   the height in the up-down direction of the center of gravity of the head is in a range from 26.0 to 30.0 mm from the horizontal plane HP, and   the right-left MOI, which is the moment of inertia around a vertical axis passing through the center of gravity of the head, is 4600 to 5500 g sq.cm.   
     
     
         17 . The golf club head according to  claim 3 , wherein
 the volume of the head is in a range from 400 to 500 cc,   the height in the up-down direction of the center of gravity of the head is in a range from 26.0 to 30.0 mm from the horizontal plane HP, and   the right-left MOI, which is the moment of inertia around a vertical axis passing through the center of gravity of the head, is 4600 to 5500 g sq.cm.