Golf club

Patent metadata

Field	Value
Publication number	US-9211459-B2
Application number	US-201414336131-A
Country	US
Kind code	B2
Filing date	Jul 21, 2014
Priority date	Jul 22, 2013
Publication date	Dec 15, 2015
Grant date	Dec 15, 2015

Abstract

The club length of a golf club is 43 inches or greater and 48 inches or less. A club inertia moment Ix about a swing axis is equal to or less than 6.90×10 3 (kg·cm 2 ). A ratio (Ihs/Ix) is equal to or greater than 0.88, if a head inertia moment about the swing axis is defined as Ihs (kg·cm 2 ). The inertia moment Ix (kg·cm 2 ) is calculated by Equation (1) below, and the inertia moment Ihs (kg·cm 2 ) is calculated by Equation (2) below:

Ix=Wc ×( Lc +60) 2 +Ic   (1)

Ihs=Wh ×( Lh +60) 2 +Ih   (2).

First claim

What is claimed is:

1. A golf club comprising:
a head, a shaft, and a grip, wherein:
a club length is 43 inches or greater and 48 inches or less;
a club inertia moment Ix about a swing axis is equal to or less than 6.90×10 3 (kg·cm 2 );
if a head inertia moment about the swing axis is defined as Ihs (kg·cm 2 ), a ratio (Ihs/Ix) is equal to or greater than 0.88; and
if a club weight is defined as Wc (kg),
a head weight is defined as Wh (kg),
an axial direction distance from a grip end to a center of gravity of the club is defined as Lc (cm),
an axial direction distance from the grip end to a center of gravity of the head is defined as Lh (cm),
a club inertia moment about the center of gravity of the club is defined as Ic (kg·cm 2 ), and
a head inertia moment about the center of gravity of the head is defined as Ih (kg·cm 2 ),

the inertia moment Ix (kg·cm 2 ) is calculated by Equation (1) below, and the inertia moment Ihs (kg·cm 2 ) is calculated by Equation (2) below:
Ix=Wc ×( Lc+ 60) 2 +Ic   (1)

Ihs=Wh ×( Lh+ 60) 2 +Ih   (2).

2. The golf club according to claim 1 , wherein:
a shaft inertia moment Iss (kg·cm 2 ) about the swing axis is equal to or less than 700; and
if a shaft weight is defined as Ws (kg),
an axial direction distance from the grip end to a center of gravity of the shaft is defined as Ls (cm), and
a shaft inertia moment about the center of gravity of the shaft is defined as Is (kg·cm 2 ),
the inertia moment Iss is calculated by Equation (3) below:
Iss=Ws ×( Ls+ 60) 2 +Is   (3).

3. The golf club according to claim 1 , wherein:
a grip inertia moment Igs (kg·cm 2 ) about the swing axis is equal to or less than 150; and
if a grip weight is defined as Wg (kg),
an axial direction distance from the grip end to a center of gravity of the grip is defined as Lg (cm), and
a grip inertia moment about the center of gravity of the grip is defined as Ig (kg·cm 2 ),
the inertia moment Igs is calculated by Equation (4) below:
Igs=Wg ×( Lg+ 60) 2 +Ig   (4).

4. The golf club according to claim 1 , wherein if a shaft inertia moment about the swing axis is defined as Iss (kg·cm 2 ), Iss/Ix is 0.092 or greater and 0.120 or less.

5. The golf club according to claim 1 , wherein if an axial direction distance from a shaft tip end to a center of gravity of the shaft is defined as Lf1, and a shaft length is defined as Lf2, Lf1/Lf2 is 0.55 or greater and 0.67 or less.

6. The golf club according to claim 1 , wherein the head weight Wh is 0.175 kg or greater and 0.200 kg or less.

7. The golf club according to claim 1 , wherein:
the inertia moment Ix is equal to or greater than 6.30×10 3 (kg·cm 2 ); and
the ratio (Ihs/Ix) is equal to or less than 0.93.

Assignees

• Dunlop Sports Co Ltd

Inventors

• Nakamura Takashi

Classifications

• A63B53/00 Primary

  Golf clubs · CPC title

• A63B2209/023

  Long, oriented fibres, e.g. wound filaments, woven fabrics, mats · CPC title

• A63B59/0074 Primary

  Human Necessities · mapped topic

• A63B53/10

  Non-metallic shafts · CPC title

• A63B53/08 Primary

  with special arrangements for obtaining a variable impact · CPC title