Image Number 9 for United States Patent #7510486.
A golf club head, more specifically a driver head, has a shell structure aft of the face that has ample strength but also can deform in the fore-aft direction for off-center hits sufficiently to provide good spring effect for such hits, comparable to hits at the center. Unwanted scatter caused by off-center hits is reduced with the spring design used in the shell structure. The shell structure can be applied to other hollow wood-type club heads. The shell structure can be provided with a coat or cover to close openings in the shell structure, and selected to make little change in stiffness or mass of the shell.