Patent ID: 7713138

Claim:
A wood type club comprising: a hollow head provided with a face part, a crown part, a sole part, and a back part and in which a hosel is formed on a heel side of the crown part so as to be connected to a shaft, wherein a toe-side part and a heel-side part located between the crown part and the sole part of the head are respectively provided with at least one concave groove opened outward in a horizontal direction and extending from the face part to the back part in a longitudinal direction so as to guide an air stream to the head in case of a swing action, wherein a whole part or a part of the concave groove is provided with a curved part bulging outwardly so that an angle in which a concave groove bottom formed from an inlet of the concave groove to an inside thereof is inclined inward with respect to a line perpendicular to the face part is smaller than an angle in which a line connecting an inlet of the concave groove bottom and an outlet thereof is inclined inward with respect to the line perpendicular to the face part, wherein the crown part is formed in a circular-arc shape in which a line, extending backward while forming an angle in a range of −15° to +15° with respect to a horizontal plane and passing through a position of an upper-end outline of the face part of the head in a reference vertical plane passing through the center of gravity of a head and the center of gravity of a face of the face part of the head upon taking a normal address posture with the head, intersects a position between a rearmost point of the crown part and 25% of a longitudinal distance from the rearmost point to the face part and a maximum vertical distance between the crown part and the line is 10 mm or less, and wherein the circular-arc shape of the crown part is a shape of a curve surface continuously formed in a toe-heel direction so as to have a band shape having a predetermined width when viewed from the reference vertical plane.