Golf club head

Abstract

This invention provides a hollow golf club head having a face portion, a crown portion, a sole portion, and a side portion, and comprising a viscoelastic body to be mounted in at least one of the face portion, crown portion, sole portion, and side portion. The viscoelastic body is mounted in a part of a portion where the viscoelastic body is to be mounted, the part corresponding to an antinode of a primary vibration mode.

1 . A hollow golf club head having a face portion, a crown portion, a sole portion, and a side portion, said head comprising a viscoelastic body to be mounted in at least one of said face portion, said crown portion, said sole portion, and said side portion, 
 wherein said viscoelastic body is mounted in a part of a portion where said viscoelastic body is to be mounted, said part corresponding to an antinode of a primary vibration mode.    
   
   
       2 . The head according to  claim 1 , wherein said part corresponding to the antinode of the primary vibration mode is specified by subjecting a model of the golf club head to mode analysis by a computer.  
   
   
       3 . The head according to  claim 1 , further comprising a plurality of viscoelastic bodies which are to be mounted in a plurality of portions of said face portion, said crown portion, said sole portion, and said side portion, 
 wherein any one of said viscoelastic bodies is to be mounted in a part of said portion where said viscoelastic body is to be mounted, said part corresponding to an antinode of the primary vibration mode.    
   
   
       4 . The head according to  claim 1 , wherein a peak value of a loss coefficient of said viscoelastic body is not less than 0.3.