| 摘要 |
A golf club head of this invention is a wood type golf club head including a face portion, a crown portion, and a sole portion. A plurality of grooves arrayed in the vertical direction of the face portion are formed in the face portion. The depth of the plurality of grooves is less than 0.025 mm. When pitches between, out of the plurality of grooves, grooves adjacent in the vertical direction of the face portion are represented by P1, P2, . . . , Pn sequentially from the upper side to the lower side of the face portion, P1≧P2≧ . . . ≧Pn, and P1>Pn. |
| 主权项 |
1. A wood type golf club head including, a crown portion on an upper side of the head, a sole portion on the lower side of the head and a face portion between the crown portion and the sole portion, wherein
a plurality of grooves arrayed in a vertical direction of the face portion are formed in the face portion, a depth of the plurality of grooves is less than 0.025 mm, and when pitches between grooves, among the plurality of grooves, that are adjacent in the vertical direction of the face portion are represented by P1, P2, . . . , Pn sequentially from an upper side to a lower side of the face portion
P1≧P2≧ . . . ≧Pn, andP1>Pn, the face portion includes a lower area, a central area, and an upper area, letting H be a height of the face portion in the vertical direction, the lower area is an area of H×0.3 from a lower end of the face portion, the central area is an area of H×0.7 from an upper end of the lower area, and the upper area is an area from the upper end of the central area to the upper end of the face portion, and when a surface roughness of the face portion is measured as an arithmetic mean roughness Ra using an average line in the vertical direction, an average value of the arithmetic mean roughness Ra of the lower area is 2 μm or more, the average value of the arithmetic mean roughness Ra of the central area is not less than 1 μm and less than 2 μm, and the average value of the arithmetic mean roughness Ra of the upper area is less than 1 μm. |
