Patent ID: 6719645
Filing Date: 2004-04-13
Classification: A63B

Abstract:
A golf club head comprising:a main body and a face member attached to the main body, the face member comprising a main portion and an extended part, the main portion forming a ball striking face, the extended part extending 5 to 30 mm backward from at least part of the edge of the ball striking face, and the extended part having a thickness less than a thickness of the main portion; wherein the extended part includes a crown-side extended part forming a part of a crown portion of the head, and a sole-side extended part forming a part of a sole portion of the head; wherein given that, in at least a cross section of the golf club head along a vertical place including a normal line drawn to the ball striking face at the center point thereof, â€œta1â€  is a thickness measured at a point on the ball striking face at a distance of 5 mm along the ball striking face from the upper edge of the ball striking face, and â€œtb1â€  is a thickness measured at a point on the crown-side extended part at a distance of 5 mm from the upper edge along the crown-side extended part, the difference (ta1âˆ’tb1) of the thickness ta1 from the thickness tb1 is in a range of from 1.0 to 2.5 mm; and wherein given that, in at least a cross section of the golf club head along a vertical plane including a normal line drawn to the ball striking face at the center point, â€œta2â€  is a thickness measured at a point on the ball striking face at a distance of 5 mm along the ball striking face from the lower edge of the ball striking face, and â€œtb2â€  is a thickness measured at a point on the sole-side extended part at a distance of 5 mm along the sole-side extended part from the lower edge, the difference (ta2âˆ’tb2) of the thickness â€œta2â€  from the thickness â€œtb2â€  is in a range of from 1.0 to 2.5 mm.