Golf club head

Abstract

A golf club head comprises a face portion defining a clubface for striking a golf ball; the face portion provided in the clubface with a high-resilience part made of a metal material having a Young's modulus E of not less than 29 (GPa) but not more than 107 (GPa); and in a measuring state of the club head which is defined as being placed on a horizontal plane such that a clubshaft center line inclines at its lie angle within a vertical plane and the clubface inclines at its face angle with respect to the vertical plane, a moment of inertia of the club head around a horizontal axis passing a gravity point of the club head in parallel with the vertical plane, being not less than 1600 (g·sq.cm) but not more than 4000 (g·sq.cm).

1 . A golf club head comprising 
 a face portion defining a clubface for striking a golf ball,    the face portion provided in the clubface with a high-resilience part made of a metal material having a Young's modulus E of not less than 29 (GPa) but not more than 107 (GPa),    in a measuring state of the club head which is defined as being placed on a horizontal plane such that a clubshaft center line inclines at its lie angle within a vertical plane and the clubface inclines at its face angle with respect to the vertical plane, a moment of inertia of the club head around a horizontal axis passing a gravity point of the club head in parallel with the vertical plane, being not less than  1600  (g·sq.cm) but not more than 4000 (g·sq.cm).    
     
     
         2 . A golf club head according to  claim 1 , wherein the product (t·E) of the Young's modulus E (GPa) and a thickness t (mm) of the high-resilience part is not less than 77 (GPa·mm) but not more than 245 (GPa·mm).  
     
     
         3 . A golf club head according to  claim 1  or  2 , wherein in the measure state, a gravity point distance which is defined as the shortest distance between the clubshaft center line and a projected point of the gravity point on the vertical plane, is not less than 26 mm bot not more than 40 mm.