Patent 7513836 was granted and assigned to Bridgestone on April, 2009 by the United States Patent and Trademark Office.
This invention provides a hollow golf club head in which the ratio of the average thickness of a sole portion to that of a crown portion is 1:0.3 to 0.8. Preferably, a crown thin-walled region is formed on the face side of the crown portion, and a crown thick-walled region is formed on the back side of the crown portion. The ratio of the average thickness of the crown thick-walled region to that of the crown thin-walled region is 1:0.5 to 0.9.