Dunlop Sports Company Limited

Sumitomo Rubber Industries Limited

Sri Sports Limited

Naoyoshi Ueda

Masahiko Ueda

Takashi Nakamura

Yasushi Sugimoto

Seiji Hayase

Wataru Kimizuka

Shimpei Oyama

Takeshi Asakura

Yuki Nagano

Satoru Hanamitsu

Naruhiro Mizutani

Tomoya Hirano

Masatoshi Kato

Daisuke Kohno

Hiroshi Abe

Kousuke Okazaki

Kenji Kii

A head includes a body member that has an opening, and a face member that includes a striking face and closes the opening. The face member includes a face portion that forms the striking face, and a peripheral portion that extends from a peripheral edge of the face portion toward a back side. The peripheral portion of the face member is welded to the body member. A weld bead that juts from the inner surface of the head is formed at a boundary position between the peripheral portion and the body member. A wall thickness at a face-side end point of the weld bead is greater than a wall thickness at a body-side end point of the weld bead. The peripheral portion has a length of less than or equal to 6 mm.

Golf club head

In a head, a center vertical cross section passing through a face center satisfies the following (a) and (b): (a) when a boundary point between an inner surface of a crown portion and an inner surface of a face portion is defined as a CF inner surface boundary point, a curvature radius of a head inner surface at the CF inner surface boundary point is 6.0 mm or greater and 10.0 mm or less, and the head thickness at the CF inner surface boundary point is 2.0 mm or greater; and(b) when a spot located 10 mm apart from the CF inner surface boundary point toward the crown side is defined as a spot C, the head thickness reduces gradually from the CF inner surface boundary point to the spot C, and the head thickness at the spot Cis 1.0 mm or less.

A golf clubincludes a head, a shaft, and a grip. A club inertia moment about a swing axis is defined as Isw. A club inertia moment about a grip end is defined as Ige. Ige is 2760 (kg&#xb7;cm) or greater and less than 2820 (kg&#xb7;cm). Isw/Ige is equal to or less than 2.42. A club weight is defined as Wc (kg), an axial direction distance from the grip end to a center of gravity of the club is defined as Lc (cm), and a club inertia moment about the center of gravity of the club is defined as Ic (kg&#xb7;cm). Isw is calculated by Equation (1) below. Ige is calculated by Equation (2) below.&#xd7;(+60)&#x2003;&#x2003;(1)&#xd7;()&#x2003;&#x2003;(2)

Golf club

A golf club set includes a plurality of golf clubshaving different loft angles. The golf clubsinclude at least one 1st golf clubA having a loft angle of less than 34 degrees, and at least one 2nd golf clubB having a loft angle of not less than 34 degrees. Each of the at least one 1st golf clubA and the at least one 2nd golf clubB comprises a clubfaceprovided with a plurality of face grooveshaving a depth. The depth of the face groovesof the at least one 2nd golf clubB is larger than the depth of the face groovesof the at least one 1st golf clubA.

Golf club set

A golf club set includes at least one first golf club whose loft angle is not less than 46 degrees and less than 56 degrees, and at least one second golf club whose loft angle is not less than 56 degrees and less than 60 degrees. The first and second golf clubs each comprise a face provided with score lines each formed by a groove having a groove bottom and a pair of opposite grooves walls which are inclined at an inclination angle with respect to a normal direction to the face so that the groove width between the opposite grooves walls is increased from the groove bottom toward the face. The inclination angle of the groove walls of the score lines of the first golf club is in the range from 28 to 42 degrees. The inclination angle of the groove walls of the score lines of the second golf club is in the range from 23 to 37 degrees and smaller than that of the first golf club.

Provided is a fitting apparatus that accurately and objectively determines an optimal swingability index, which is a swingability index of a golf club suited to a golfer. The fitting apparatus is provided with an acquisition unit, a calculation unit, and a determination unit. The acquisition unit acquires a measurement value obtained by measuring a swing action of a test club by the golfer with a measurement device. The calculation unit calculates a swing index indicating a feature amount of the swing action, based on the measurement value. The determination unit determines the optimal swingability index, according to a magnitude of the swing index.

Golf club fitting apparatus

A golf clubincludes a head, a shaft, and a grip. A club inertia moment about a swing axis is defined as Isw. A club inertia moment about a grip end is defined as Ige. Ige is 2920 (kg&#xb7;cm) or greater and less than 2970 (kg&#xb7;cm). Isw/Ige is equal to or less than 2.48. A club weight is defined as Wc (kg), an axial direction distance from the grip end to a center of gravity of the club is defined as Lc (cm), and a club inertia moment about the center of gravity of the club is defined as Ic (kg&#xb7;cm). Isw is calculated by Equation (1) below. Ige is calculated by Equation (2) below.&#xd7;(+60)&#x2003;&#x2003;(1)&#xd7;()&#x2003;&#x2003;(2)

A golf clubincludes a head, a shaft, and a grip. A club inertia moment about a swing axis is defined as Isw. A club inertia moment about a grip end is defined as Ige. Ige is 2870 (kg&#xb7;cm) or greater and less than 2920 (kg&#xb7;cm). Isw/Ige is equal to or less than 2.46. A club weight is defined as Wc (kg), an axial direction distance from the grip end to a center of gravity of the club is defined as Lc (cm), and a club inertia moment about the center of gravity of the club is defined as Ic (kg&#xb7;cm). Isw is calculated by Equation (1) below. Ige is calculated by Equation (2) below.sw=&#xd7;(+60)&#x2003;&#x2003;(1)ge=&#xd7;()&#x2003;&#x2003;(2)

A golf clubincludes a head, a shaft, and a grip. A club inertia moment about a swing axis is defined as Isw. A club inertia moment about a grip end is defined as Ige. Ige is 2820 (kg&#xb7;cm) or greater and less than 2870 (kg&#xb7;cm). Isw/Ige is equal to or less than 2.42. A club weight is defined as Wc (kg), an axial direction distance from the grip end to a center of gravity of the club is defined as Lc (cm), and a club inertia moment about the center of gravity of the club is defined as Ic (kg&#xb7;cm). Isw is calculated by Equation (1) below. Ige is calculated by Equation (2) below.&#xd7;(+60)&#x2003;&#x2003;(1)&#xd7;()&#x2003;&#x2003;(2)

An iron-type golf club head comprises a head main body and a face plate attached thereto. The face plate has an annular outer edge portion fixed to the head main body, and a noncontact portion not contacting with the head main body. The noncontact portion includes a first thin part and a second thin part having a thickness less than that of the outer edge portion. The first thin part extends in a peripheral side along the upper edge, the toe-side edge and the lower edge of the face plate. The second thin part is formed to have a thickness less than that of the first thin part. The area of the first thin part is 10% to 35% of the area of the noncontact portion. The area of the second thin part is 65% to 90% of the area of the noncontact portion.

Iron-type golf club head

An iron-type golf club head has a face for hitting a ball, a sole extending backward from the lower edge of the face and extending in the toe-heel direction of the head so as to define the bottom surface of the club head, and a hosel extending upward in a heel-side of the face and provided with a shaft inserting hole. The club head is composed of a head main body including the face, and a weight member having a specific gravity larger than that of the head main body and fixed to the head main body. The weight member integrally includes a first part extending in the toe-heel direction in the sole, and a second part constituting at least substantial portion of the hosel.

An evaluation method for hit feeling of a sport implement according to the present invention includes an acceleration measurement step for measuring acceleration of a sport hitting tooland a data analysis step for analyzing data obtained in the measurement. In the data analysis step, an amount of change in acceleration in a first cycle of vibration after hitting is calculated. The evaluation method evaluates hit feeling to be felt by a person, using the amount of change in the acceleration. Preferably, in the data analysis step, an amount of change in acceleration in the first cycle of predetermined time is calculated. The predetermined time is within 1.5 msec from the time of hitting. Preferably, the sport hitting toolhas the hitting section detachably attached to a shaft section.

Method for evaluating hit feeling

The evaluation method includes a first step, by using measurement means Mwhich can measure force F acting between a swing subject and the sport hitting tool or a specific directional component Fthereof, obtaining measured value Vf of the force F or the force Fat time after the impact, and a second step of determining the hit feeling on the basis of the measured value Vf at least at the one time. Preferably, the force F or the force Fis force Fs containing a component in a shear direction. Preferably, in the first step, the measured values Vf in a specific interval Zfrom time Tto Tafter the impact are obtained chronologically. Preferably, the evaluation is made based on a difference between a maximum value and a minimum value of the measured values Vf.

A headincludes a head body hand a neck part n. The head body hand the neck part nare joined. The head body hhas a body side joint surface sand a first recessed part opened in the body side joint surface s. A space vis formed by the first recessed part r. The neck part nhas a neck side joint surface brought into surface contact with the body side joint surface sand a shaft hole. An abutted boundary surface Pt passes through a vicinity adof a head height lowest point. When a plane perpendicular to an axis line z of the shaft holeis defined as PL, and an angle between the plane PL and the abutted boundary surface Pt is &#x3b8; degree, the angle &#x3b8; is a plus value.

A valuation method of the present invention quantitatively estimates hit feeling of a sport hitting tool. The evaluation method includes: a first step of using a measuring means Mcapable of measuring forces F acting between a swing subject and the sport hitting tool or specific directional components Fthereof to obtain values of the forces F or the components Fat times after impact; and a second step of deciding the hit feeling based on the value of the force F or the component Fat at least one of the times. Preferably, the values of the forces F or the components Fin a specified period Zbetween a time Tand a time Tafter the impact are obtained in time series in the first step. Preferably, the hit feeling is evaluated based on an integrated value Sf of the forces F or the components Fin the specified period Zin the second step.

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Kobe, Japan

Naoyoshi Ueda