Yamaha Corporation

Tatsuya Hirakawa

Atsushi Uchida

Itsushi Nagamoto

Tatsuo Nakanishi

Mutsumi Harada

Hiroaki Inoue

Itsushi Magamoto

Noburo Sumikawa

By hot pressing a cold rolled &bgr; type titanium alloy which has not been subjected to solution heat treatment into a predetermined shape, it is possible to obtain a part with a cold rolled metallurgical texture in its approximately central portion in the thickness direction, and a solution heat treatment metallurgical texture in its other portions, and a golf club head is manufactured using this part as a face member.

Golf club head and method of manufacturing the same

A metal wood golf club head including a sole plate and a weight body which is fastened to this sole plate via a spacer. A recess which accommodates the spacer and weight body is formed in a portion of the sole plate, an undercut part is formed in the inside circumferential portion of the recess, and a circumferential groove is formed in the outer circumferential portion of the weight body. When the weight body is press-fitted in the recess with the spacer in between, the spacer is forcibly engaged with the undercut part and circumferential groove, thus allowing the weight body to be firmly fastened to the recess of the sole plate of the club head.

Structure and method of fastening a weight body to a golf club head

In construction of a wood type golf club head, its main body made of a material unsuited for plastic deformation such as FRP and its and hosel made of a material suited for plastic deformation such as metal are separably coupled to each other. Subtle adjustment of ball striking characteristics such as loft and lie angles can be practiced quite freely independently of the material used for the main body.

Golf club head

In construction of a golf club head made of metal or fiber reinforced plastics, its hosel is configured such that rigidity in the toe-to-heel direction is larger than that in the ball-shooting direction. During swinging of the club to impact a ball, not only does the shaft of the club flex but also its hosel. This double flexing results in increased impact on the ball. In addition, the specified rigidity distribution avoids undesirable toe-down deformation which tends to cause mishitting of the ball.

Growing community of inventors

Hamamatsu, Japan

Tatsuya Hirakawa