摘要:
A golf club head 2 comprises: a porous part Ps including a porous metal and integrally formed; and a non-porous part NPs. The porous part Ps constitutes at least a part of a sole 8. The porous part Ps has a whole thickness part Pt occupying a whole thickness of the sole 8. Preferably, a rate Ra of an area occupied by the whole thickness part Pt among an area of the sole is equal to or greater than 15%. Preferably, the porous part Ps and the non-porous part NPs are welded mutually. In the disposal of the porous part Ps in the head 2, preferably, a substituted head obtained by substituting the porous part Ps with the same material as that of the non-porous part NPs adjacent to the porous part Ps is considered.
摘要:
On the basis of a surface shape appearing at a predetermined point moment by moment during rotation of a golf ball having numerous dimples on its surface, a data constellation regarding a parameter dependent on a surface shape of the golf ball is calculated. A preferable parameter is a distance between an axis of the rotation and the surface of the golf ball. Another preferable parameter is a volume of space between a surface of a phantom sphere and the surface of the golf ball. Fourier transformation is performed on the data constellation to obtain a transformed data constellation. On the basis of a peak value and an order of a maximum peak of the transformed data constellation, an aerodynamic characteristic of the golf ball is determined. The peak value and the order of the maximum peak are calculated for each of PH rotation and POP rotation.
摘要:
A computer (16) for capturing a colored moving image photographed by photographing means (14, 15) has an extraction means for extracting images having necessary swing postures as check-point images from a large number of still images constituting the color moving image; a means for obtaining a coordinate of a position of each of attention-focused points, which operate, in each of the check-point images, while a golfer (11) is swinging; a means for diagnosing a golfer's swing form by setting a plurality of diagnosis items for each trajectory pattern obtained by a ball motion measuring apparatus (20) to classify behavior of a golf ball and by comparing numerical data generated from data of the coordinate of the position of each of the attention-focused points with a judgement value set in each of a plurality of diagnosis items; and a means for outputting an advice drill corresponding to a result of a diagnosis.
摘要:
A golf swing-measuring system including a computer (16) for capturing a colored moving image obtained by photographing a golfer (11) who swings by gripping a golf club (13). The computer (16) selects and extracts one or more images each showing a swing posture as check-point images such as an address image, a take-back shaft 8 o'clock image, a take-back shaft 9 o'clock image, a take-back unskillful arm horizontal image, a top image, a downswing unskillful arm horizontal image, a downswing shaft 9 o'clock image, an impact image, a follow-through shaft 3 o'clock image, and a finish image and extracts from a large number of still images constituting said color moving image. Thereafter the computer (16) obtains coordinates of positions of attention-focused points that operate in said check-point images when said golfer swings.
摘要:
A golf ball 2 has numerous craters 8 on its surface. The craters 8 are arranged randomly. Of the surface of the golf ball 2, a part other than the craters 8 is a land 10. By the craters 8 and the land 10, a rugged pattern is formed on the golf ball 2. A process for designing the rugged pattern includes the steps of:(1) assuming a plurality of states;(2) assuming a large number of cells on a spherical surface;(3) deciding an initial state of each cell;(4) determining whether or not to change a state of the each cell based on states of a plurality of cells located adjacent to the each cell;(5) updating the state of the each cell based on the determination; and(6) assigning a land 10 or a recess to the each cell according to the state of the each cell.
摘要:
The present invention relates to a method of manufacturing an FRP tubular body. The manufacturing method includes the steps of winding a fiber reinforced resin member containing a fiber and a matrix resin around a mandrel, thereby obtaining an intermediate formed body, winding a wrapping tape around an outer peripheral surface of the intermediate formed body (6) with an application of a tension, curing the matrix resin in the intermediate formed body having the wrapping tape wound therearound, and pulling the mandrel out and removing the wrapping tape after the curing step, thereby obtaining a cured tubular body. It is preferable that a fabric tape should be used as the wrapping tape. It is preferable that a tensile stress to be applied to the fabric tape (8) should be set to be equal to or higher than 5 (Mpa) and is equal to or smaller than 150 (Mpa) at the tape winding step. In the manufacturing method, the matrix resin can be effectively extracted at a subsequent step to the winding step.
摘要:
A hollow golf club head comprises: a face portion whose front face defines a club face for hitting a ball; a crown portion intersecting the club face at the upper edge thereof; and a sole portion intersecting the club face at the lower edge thereof, wherein at least one of the sole portion and the crown portion is provided along the front edge thereof with a face-backing zone in which the rigidity is gradually increased from its toe-side end and heel-side end toward the center thereof.
摘要:
Reference points (M1 through M17) are specified in colors at two or more positions longitudinally spaced at a given interval on a golf club shaft (11a) and one or more positions selected from among a golfer's head and the like. A moving image of a golfer's swing is photographed by cameras (13-1, 13-2). The moving image of the swing is converted into a plurality of still images. The still images are stored in a computer (14). Evaluation items to be checked including a swing posture and a shaft angle in a range from an addressing state till an impact state are expressed by numeric values, based on coordinate data of each of the reference points (M1 through M17) disposed on a plurality of the still images. The data expressed by the numeric values are compared with judging data inputted to the computer (14) in advance as ideal values.
摘要:
A fitting method includes steps of preparing a relationship C of a shaft flex point Y and a face angle X before impact or at impact; measuring a subject's face angle X before impact or at impact by using a test club; and selecting a shaft fitted to the subject on the basis of the measured face angle X and the relationship C. The relationship C is created by using correlation R of the face angle before impact or at impact and a hitting result. The correlation R is based on hitting results of a plurality of golf clubs having different shaft flex point rates. Preferably, the relationship C is a relational expression F1.
摘要:
A hollow golf club head has: a moment of inertia Ix around a vertical axis of 4500 to 5900 g sq·cm; and a moment of inertia Iy around an inclined axis of 5300 to 6800 g sq·cm, which satisfy Iy=