Sumitomo Rubber Industries Limited

Kenji Takasu

Naruhiro Mizutani

Daisuke Kohno

Takashi Nakamura

Takashi Nakano

Seiji Hayase

Masahiko Ueda

Wataru Kimizuka

A golf club includes a head; a shaft having a tip end and a butt end; and a grip. The golf club has a length of greater than or equal to 45.0 inches. The head has a weight of greater than or equal to 195 g. The golf club has a club moment about a rotation center of less than or equal to 22.74 (kg&#xb7;cm), the rotation center being a point 100 mm away from a butt end of the grip. The shaft may have a weight of less than or equal to 40 g. The golf club has a weight of greater than or equal to 280 g. A butt end region having a distance from the butt end of the grip of 100 mm or less may have a weight of greater than or equal to 27 g. This golf club can exhibit an on-plane effect.

Golf club

A golf club includes a head; a shaft having a tip end and a butt end; a grip; and a weight member that is located in a butt end region having a distance from a butt end of the grip of less than or equal to 100 mm. The grip and the weight member constitute a grip-weight portion. The shaft, the grip, and the weight member constitute a shaft-grip-weight portion. The shaft has a weight of less than or equal to 40 g. The shaft has a shaft torque of less than or equal to 7.0&#xb0;. The grip-weight portion has a weight of greater than or equal to 40 g. A ratio W1/W3 of a weight W1 of the butt end region to a weight W3 of the shaft-grip-weight portion is greater than or equal to 0.40.

A golf clubincludes a head, a shaft, and a grip. The clubhas a forward club flex of greater than or equal to 170 mm. The forward club flex is measured for a golf club in the completed state. The weight of the head is denoted by Wh, and the weight of the club is denoted by Wc. Wh/Wc is greater than or equal to 0.72. With the golf club, a force acting on the player's body during a swing can be reduced. The golf clubcan stabilize swing.

A shaft includes a plurality of fiber reinforced layers. The fiber reinforced layers include a plurality of hoop layers and a plurality of straight layers. The straight layers include at least one full length straight layer. At least two of the hoop layers and at least two of the straight layers constitute an alternate lamination of the hoop layers and the straight layers. The hoop layers may include a first butt partial hoop layer and a second butt partial hoop layer that is longer in an axial direction than the first butt partial hoop layer. The first butt partial hoop layer may have a weight per unit area of greater than that of the second butt partial hoop layer.

Golf club shaft

A golf club includes a head; a shaft having a tip end and a butt end; a grip; and a weight member that is located in a butt end region having a distance from a butt end of the grip of less than or equal to 100 mm. The grip and the weight member constitute a grip-weight portion. The shaft, the grip, and the weight member constitute a shaft-grip-weight portion. The shaft has a weight Ws of less than or equal to 40 g. The shaft has a flex point ratio of less than or equal to 50%. The grip-weight portion has a weight Wof greater than or equal to 40 g. A ratio W/Wof a weight Wof the butt end region to a weight Wof the shaft-grip-weight portion is greater than or equal to 0.40.

A golf club includes a head; a shaft; a grip; and a weight member that is located in a butt end region. The grip and the weight member constitute a grip-weight portion. The shaft, the grip, and the weight member constitute a shaft-grip-weight portion. The golf club has a length of greater than or equal to 45.0 inches. The golf club has a weight of less than 295 g. The head has a weight of greater than or equal to 195 g. The grip-weight portion has a weight of greater than or equal to 40 g. W/Wis greater than or equal to 0.40, where Wrepresents a weight (g) of the butt end region, and Wrepresents a weight (g) of the shaft-grip-weight portion.

A golf club includes a head; a shaft; a grip; and a weight member that is located in a butt end region. The grip and the weight member constitute a grip-weight portion. The shaft, the grip, and the weight member constitute a shaft-grip-weight portion. The head has a weight of greater than or equal to 195 g. The grip-weight portion has a weight of greater than or equal to 40 g. The shaft has a weight of less than or equal to 40 g. The golf club has a weight of greater than or equal to 275 g and less than or equal to 300 g. W/Wis greater than or equal to 0.40, where Wrepresents a weight (g) of the butt end region, and Wrepresents a weight (g) of the shaft-grip-weight portion.

A golf club includes a head; a shaft having a tip end and a butt end; a grip; and a weight member that is located in a butt end region having a distance from a butt end of the grip of 100 mm or less. The grip and the weight member constitute a grip-weight portion. The shaft, the grip, and the weight member constitute a shaft-grip-weight portion. The golf club has a weight of less than 295 g. The head has a weight of greater than or equal 195 g. The grip-weight portion has a weight of greater than or equal to 40 g. The head has a gravity center distance of greater than or equal to 44.5 mm. A ratio W/Wof a weight W(g) of the butt end region to a weight W(g) of the shaft-grip-weight portion is greater than or equal to 0.40.

A golf club includes a head, a shaft, and a grip. The golf club has a club vibration frequency of less than or equal to 210 cpm. The golf club has a swing weight of greater than or equal to D. With the golf club, a force acting on the player's body during a swing can be reduced. The golf club can stabilize swing.

A shafthas a forward flex of equal to or longer than 130 mm and equal to or shorter than 178 mm. When the forward flex is represented by f, and a backward flex is represented by f, f/(f+f) is equal to or greater than 0.46 and equal to or less than 0.50. When a distance between a butt end Bt and a center of gravity Gs of the shaft is represented by L (centimeter), and a weight of the shaft is represented by Ws (kilogram), a butt end GLL is calculated by the following formula:butt endwherein the butt end GLL (kg&#xb7;cm) is equal to or less than 110 kg&#xb7;cm.

A golf clubincludes a head, a shaft, and a grip. The clubhas a forward club flex of greater than or equal to 140 mm. The forward club flex is measured for a golf club in the completed state. The griphas a weight Wg of less than or equal to 30 g. With the golf club, a force acting on the player's body during a swing can be reduced. The golf clubcan stabilize swing.

Growing community of inventors

Kobe, Japan

Kenji Takasu