GOLF CLUB HEAD WITH IMPROVED INERTIA PERFORMANCE
A golf club head that is capable improving on the inertia properties of a golf club head all while also improving the Center of Gravity (CG) location is disclosed herein. More specifically, the golf club head in accordance with the present invention achieves a relative low Moment of Inertia (MOI) about the Z-axis (MOI-Z) as well as a relatively low MOI about the Shaft-axis (MOI-SA), all combined with a high MOI about the X and Y-axis (MOI-X and MOI-Y) and maintaining a consistently and relatively low CG location measured along a direction tangent to the hosel axis along the X-Y plane (CG-B).
1 . A golf club head comprising:
a frontal portion further comprising a striking face that helps define a face center, located at a forward portion of said golf club head;
a rear portion located aft of said striking face; and
at least one first weighting member located near a central portion of said golf club head in a heel to toe orientation, substantially in line with and behind said face center;
wherein an x-axis is defined as a horizontal axis tangent to a geometric center of said striking face with the positive direction towards a heel of said golf club head, a y-axis is a vertical axis orthogonal to said x-axis with a positive direction towards a crown of said golf club head, and a z-axis being orthogonal to both said x-axis and said y-axis with a positive direction towards said frontal portion of said golf club head, and
wherein said golf club head has a moment of inertia about said y-axis (MOI-Y) and moment of inertia about said z-axis (MOI-Z), and said golf club head has a MOI-Y to MOI-Z ratio of greater than about 1.50.
2 . The golf club head of claim 1 , wherein said golf club head has a MOI-Y to MOI-Z ratio of greater than about 1.57.
3 . The golf club head of claim 2 , wherein said golf club head has a MOI-Y to MOI-Z ratio of greater than about 1.68.
4 . The golf club head of claim 1 , wherein said golf club head has a MOI-Z measurement of less than about 268 kg-mm 2 , and
wherein said golf club head has a MOI-Y measurement of greater than about 420 kg-mm 2 , and
wherein said golf club head has a moment of inertia about a shaft axis (MOI-SA) measurement of less than about 850 kg-mm 2 .
5 . The golf club head of claim 1 , wherein if said MOI-Y number is greater than about 500, said MOI-Z number is governed by the equation;
MOI-Z≤(0.47*MOI-Y)+33.
6 . The golf club head of claim 1 , wherein said golf club head has a moment of inertia about said x-axis (MOI-X), and said golf club head has a MOI-X to MOI-Z ratio of greater than about 1.10.
7 . The golf club head of claim 6 , wherein said golf club head has a MOI-X to MOI-Z ratio of greater than about 1.20.
8 . The golf club head of claim 7 , wherein said golf club head has a MOI-X to MOI-Z ratio of greater than about 1.28.
9 . The golf club head of claim 8 , wherein said golf club head has a MOI-Z measurement of less than about 268 kg-mm 2 , and
wherein said golf club head has a MOI-X measurement of greater than about 320 kg-mm 2 , and
wherein said golf club head has a moment of inertia about a shaft axis (MOI-SA) measurement of less than about 850 kg-mm 2 .
10 . The golf club head of claim 1 , wherein said golf club head further comprises a second weighting member located near a central portion of said golf club head along a heel to toe orientation, substantially in line with and behind said face center, and located rearward of said first weighting member.
11 . A golf club head comprising:
a frontal portion further comprising a striking face that helps define a face center, located at a forward portion of said golf club head;
a rear portion located aft of said striking face; and
at least one first weighting member located near a central portion of said golf club head in a heel to toe orientation, substantially in line with and behind said face center;
wherein an x-axis is defined as a horizontal axis tangent to a geometric center of said striking face with the positive direction towards a heel of said golf club head, a y-axis is a vertical axis orthogonal to said x-axis with a positive direction towards a crown of said golf club head, and a z-axis being orthogonal to both said x-axis and said y-axis with a positive direction towards said frontal portion of said golf club head, and
wherein said golf club head has a moment of inertia about said x-axis (MOI-X), a moment of inertia about said z-axis (MOI-Z), and CG-Z numbers that satisfies the equation below;
MOI
-
X
MOI
-
Z
≥
(
6.7501
*
CG
-
Z
)
-
99.30
.
12 . The golf club head of claim 11 , wherein said golf club head has a moment of inertia about said y-axis (MOI-Y), MOI-Z, and CG-Z numbers that satisfies the equation below;
MOI
-
Y
MOI
-
Z
≥
(
11.349
*
CG
-
Z
)
-
175.76
.
13 . The golf club head of claim 12 , wherein said golf club head has MOI-X, MOI-Y, MOI-Z, and CG-Z numbers that satisfies the equation below;
(
MOI
-
X
+
MOI
-
Y
)
MOI
-
Z
≥
(
18.67
*
CG
-
Z
)
-
296.63
.
14 . The golf club head of claim 13 , wherein said golf club head has a MOI-Z measurement of less than about 268 kg-mm 2 ,
wherein said golf club head has a MOI-Y measurement of greater than about 420 kg-mm 2 ,
wherein said golf club head has a MOI-X measurement of greater than about 320 kg-mm 2 , and
wherein said golf club head has a moment of inertia about a shaft axis (MOI-SA) measurement of less than about 800 kg-mm 2 .
15 . The golf club head of claim 14 , wherein said golf club head has a CG-Z measurement of between about 25 mm and about 40 mm.
16 . The golf club head of claim 15 , wherein said golf club head has a CG-Z measurement of between about 26 mm and about 38 mm.
17 . The golf club head of claim 16 , wherein said golf club head has a CG-Z measurement of between about 27 mm and about 36 mm.
18 . The golf club head of claim 11 , wherein said golf club head further comprises a second weighting member located near a central portion of said golf club head along a heel to toe orientation, substantially in line with and behind said face center, and located rearward of said first weighting member.
19 . The golf club head of claim 18 , wherein said frontal portion is made out of a first material having a first density,
wherein said rear portion is made out of a second material having a second density,
wherein said first weighting member and said second weighting member are both made out of a third material having a third density, and
wherein said third density is greater than said first and said second density.
20 . The golf club head of claim 19 , wherein said first density is greater than said second density.