Golf club shaft and golf club
A metal foil satisfies following conditional equations (1), (2) and (3) to smoothly increase rigidity in the longitudinal direction of the shaft main body from a distal end side to a base end side while increasing a weight of a wound part of the metal foil 0.50< Lmf/Ls (1) Lmr/Ls <0.90 (2) 0.03< Wm/Ws <0.09 (3) where Lmf: a length from a distal end position in the longitudinal direction of the shaft main body to a winding start position of the metal foil, Lmr: a length from the distal end position in the longitudinal direction of the shaft main body to a winding end position of the metal foil, Ls: a length of the shaft main body, Wm: a weight of the metal foil, and Ws: a weight of the shaft main body.
1. A golf club shaft comprising a shaft main body formed by winding and thermally curing a prepreg made by impregnating reinforced fibers with a thermosetting resin, wherein
a metal foil is located at and wound around a part in a longitudinal direction of the shaft main body, and wherein
the shaft main body comprises:
a pair of entire-length layers formed by thermally curing a pair of entire-length prepregs positioned at an inner layer side and at an outer layer side; and
a distal-end partial layer formed by thermally curing a distal-end partial prepreg positioned between the pair of entire-length layers at the distal end,
wherein the metal foil is positioned near the base end between the pair of entire-length layers, and
wherein the distal-end partial layer and the metal foil are arranged not to mutually overlap at the distal end nor at the base end with respect to a same lamination area between the pair of entire-length layers, and wherein
the metal foil satisfies following conditional equations (1), (2) and (3) to smoothly increase rigidity in the longitudinal direction of the shaft main body from a distal end side to a base end side while increasing a weight of the wound part of the metal foil
0.50 <Lmf/Ls (1)
Lmr/Ls <0.90 (2)
0.03 <Wm/Ws <0.09 (3)
where
Lmf: a length from a distal end position in the longitudinal direction of the shaft main body to a winding start position of the metal foil,
Lmr: a length from the distal end position in the longitudinal direction of the shaft main body to a winding end position of the metal foil,
Ls: a length of the shaft main body,
Wm: a weight of the metal foil, and
Ws: a weight of the shaft main body.
2. The golf club shaft according to claim 1 , wherein a following conditional equation (4) is satisfied
0.05 <Lmt/Ls <0.35 (4)
where
Lmt: a length from the winding start position to the winding end position of the metal foil, and
Ls: the length of the shaft main body.
3. The golf club shaft according to claim 1 , wherein a density of the metal foil is 7.5 g/cm 3 or more.
4. The golf club shaft according to claim 1 , wherein the metal foil is a copper foil.
5. A golf club that is formed by attaching a club head and a grip to the golf club shaft according to claim 1 .
6. The golf club shaft according to claim 1 , wherein a following conditional equation (3′) is satisfied:
0.039 <Wm/Ws <0.069 (3′).