Patent ID: 7887436

Claim:
A wood-type hollow golf club head with a hollow structure comprising: a face portion defining a club face for hitting a ball; and a hosel tubular portion provided with a shaft inserting hole defining a clubshaft center line, wherein in a cross section of the hollow structure taken along a vertical plane (VP 2 ) including the center of gravity (G) of the club head and a sweet spot (SS) of the club face, a face progression is in a range of from 21 to 27 mm, and in a cross section of the hollow structure taken along a horizontal plane (HP 2 ) including the center of gravity (G), a ratio (S 1 /S 2 ) of the area (S 1 ) of a first right-angle triangle (OGP) to the area (S 2 ) of a second right-angle triangle (ORQ) is in a range of from 4 to 10, wherein the first right-angle triangle (OGP)is defined by three sides: a side between the center of gravity (G) and an intersecting point (O) of the clubshaft center line with the horizontal plane (HP 2 ); a side PG extending from the center of gravity (G) in parallel with the back-and-forth direction of the club head; and a side PO extending from the intersecting point (O) in parallel with the heel-and-toe direction of the club head, and the second right-angle triangle (ORQ)is defined by three points: the intersecting point (O); an intersecting point (R) between a straight line drawn parallel with the heel-and-toe direction, passing through the intersecting point (O), and a straight line (Lh) drawn parallel with the back-and-forth direction and tangentially to the on-the-heel-side extreme end (H) of the club head; and an intersecting point (Q) between the straight line (Lh) and a straight line (Lf) drawn parallel with the heel-and-toe direction, passing through an intersecting point (F) between the club face and a straight line drawn parallel with the back-and-forth direction, passing through the center of gravity (G), wherein the area S 1 of the first right-angle triangle (OGP) is not less than 350 sq.mm and not more than 700 sq.mm.