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US 12,582,882 B2Granted
Golf club shaft
AssigneeSumitomo Rubber Industries, Ltd.
InventorTakashi Nakano
Life of this patent
Estimating the term…
Abstract
A shaft has a weight of 50 g or less. A forward flex is 110 mm or less. A backward flex is 100 mm or less. A shaft torque is 4.0° to 6.5°. The shaft includes a first hoop layer, a second hoop layer longer than the first hoop layer, and a third hoop layer longer than the second hoop layer. An outer diameter at a position 550 mm apart from a tip end is D5. An outer diameter at a position 950 mm apart from the tip end is D9. A crushing strength at the position 550 mm apart from the tip end is F5. A crushing strength at the position 950 mm apart from the tip end is F9. F5/D5 is 1.5 or greater and 2.5 or less. F9/D9 is 1.0 or greater and 2.0 or less. A difference (F5−F9) is 4 kgf or less.
Claims16
A golf club shaft formed by a plurality of fiber reinforced resin layers and comprising a tip end and a butt end, wherein
- the golf club shaft has a shaft weight of less than or equal to 50 g,
- the golf club shaft has a forward flex of less than or equal to 110 mm and a backward flex of less than or equal to 100 mm,
- the golf club shaft has a shaft torque of greater than or equal to 4.0° and less than or equal to 6.5°,
- the fiber reinforced resin layers include a first hoop layer that is disposed from the butt end to a first position, a second hoop layer that is longer than the first hoop layer and is disposed from the butt end to a second position, and a third hoop layer that is longer than the second hoop layer and is disposed from the butt end to a third position, and
- when an outer diameter of the golf club shaft at a position located 550 mm apart from the tip end is denoted by D5 (mm), an outer diameter of the golf club shaft at a position located 950 mm apart from the tip end is denoted by D9 (mm), a crushing strength at the position located 550 mm apart from the tip end is denoted by F5 (kgf), and a crushing strength at the position located 950 mm apart from the tip end is denoted by F9 (kgf), then,
- F5/D5 is greater than or equal to 1.5 and less than or equal to 2.5,
- F9/D9 is greater than or equal to 1.0 and less than or equal to 2.0, and
- a difference (F5-F9) is less than or equal to 4 kgf.
5 more elements
A golf club shaft formed by a plurality of fiber reinforced resin layers and comprising a tip end and a butt end,
- wherein the golf club shaft has a shaft weight of less than or equal to 50 g,
- the fiber reinforced resin layers include a first hoop layer that is disposed from the butt end to a first position, a second hoop layer that is longer than the first hoop layer and is disposed from the butt end to a second position, and a third hoop layer that is longer than the second hoop layer and is disposed from the butt end to a third position,
- the first hoop layer and the second hoop layer are butt partial hoop layers,
- the third hoop layer is a full length hoop layer,
- the second hoop layer is disposed on an outer side than the first hoop layer,
- the third hoop layer is disposed on the outer side than the second hoop layer, and
- the first hoop layer and/or the second hoop layer is thicker than the third hoop layer and
- when an outer diameter of the golf club shaft at a position located 550 mm apart from the tip end is denoted by D5 (mm), an outer diameter of the golf club shaft at a position located 950 mm apart from the tip end is denoted by D9 (mm), a crushing strength at the position located 550 mm apart from the tip end is denoted by F5 (kgf), and a crushing strength at the position located 950 mm apart from the tip end is denoted by F9 (kgf), then:
- F5/D5 is greater than or equal to 1.5 and less than or equal to 2.5,
- F9/D9 is greater than or equal to 1.0 and less than or equal to 2.0, and
- a difference (F5-F9) is less than or equal to 4 kgf.
8 more elements
A golf club shaft formed by a plurality of fiber reinforced resin layers and comprising a tip end and a butt end,
- wherein the golf shaft has a shaft weight of less than or equal to 50 g,
- the fiber reinforced resin layers include a first hoop layer that is disposed from the butt end to a first position, a second hoop layer that is longer than the first hoop layer and is disposed from the butt end to a seco ad position, and a third hoop layer that is longer than the second hoop layer and is disposed from the butt end to a third position,
- the first hoop layer and the second hoop layer are bott partial hoop lavers,
- the third hoop layer is a full length hoop layer,
- the second hoop layer is displayed an outer side than the first hoop layer,
- the third hoop layer is disposed on the outer side than the second hoop layer,
- the first hoop layer and/or the second hoop layer is thicker than the third hoop layer
- a three-point flexural strength at a position located 90 mm apart from the tip end is greater than or equal to 190 kgf, a three-point flexural strength at a position located 175 mm apart from the tip end is greater than or equal to 70 kgf, a three-point flexural strength at a position located 525 mm apart from the tip end is greater than or equal to 65 kgf, and a three-point flexural strength at a position located 175 mm apart from the butt end is greater than or equal to 90 kgf,
- an impact absorbing energy of a tip portion of the golf club shaft is greater than or equal to 3.4 J, and
- a crushing strength at a position located 550 mm apart from the tip end is greater than or equal to 11 kgf, a crushing strength at a position located 650 mm apart from the tip end is greater than or equal to 11 kgf, a crushing strength at a position located 750 mm apart from the tip end is greater than or equal to 11 kgf, a crushing strength at a position located 850 mm apart from the tip end is greater than or equal to 11 kgf, and a crushing strength at a position located 950 mm apart from the tip end is greater than or equal to 11 kgf.
7 more elements
Dependencies are inferred from the claim text.