U.S. patent application number 17/323725 was filed with the patent office on 2021-09-02 for golf club head with improved inertia performance.
This patent application is currently assigned to Acushnet Company. The applicant listed for this patent is Acushnet Company. Invention is credited to Richard L. Cleghorn, Darryl C. Galvan, Charles E. Golden, Peter Larsen, Stephen S. Murphy, Ryuichi Sugimae.
Application Number | 20210268344 17/323725 |
Document ID | / |
Family ID | 1000005597949 |
Filed Date | 2021-09-02 |
United States Patent
Application |
20210268344 |
Kind Code |
A1 |
Sugimae; Ryuichi ; et
al. |
September 2, 2021 |
GOLF CLUB HEAD WITH IMPROVED INERTIA PERFORMANCE
Abstract
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).
Inventors: |
Sugimae; Ryuichi; (San
Diego, CA) ; Galvan; Darryl C.; (El Cajon, CA)
; Murphy; Stephen S.; (Carlsbad, CA) ; Golden;
Charles E.; (Encinitas, CA) ; Larsen; Peter;
(San Marcos, CA) ; Cleghorn; Richard L.;
(Oceanside, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Acushnet Company |
Fairhaven |
MA |
US |
|
|
Assignee: |
Acushnet Company
Fairhaven
MA
|
Family ID: |
1000005597949 |
Appl. No.: |
17/323725 |
Filed: |
May 18, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16780040 |
Feb 3, 2020 |
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17323725 |
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16539622 |
Aug 13, 2019 |
11027178 |
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16780040 |
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16219651 |
Dec 13, 2018 |
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16539622 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A63B 2053/0491 20130101;
A63B 53/0433 20200801; A63B 53/042 20200801; A63B 53/0437 20200801;
A63B 53/0408 20200801; A63B 2209/00 20130101 |
International
Class: |
A63B 53/04 20060101
A63B053/04 |
Claims
1. A golf club comprised of a golf club head, a shaft having a
shaft axis coupled to the golf club head at a first end of the
shaft and a grip coupled to the shaft at a second end of the shaft,
wherein the golf club head comprises: a frontal portion comprised
of metal comprising a striking face having a face center located at
a forward portion of said golf club head; a non-metallic rear
portion located aft of said striking face comprising a crown at an
upper portion of said golf club head and a sole on a bottom portion
of said golf club head; and wherein an x-axis is defined as a
horizontal axis tangent to said face center with a positive x
direction towards a heel of said golf club head, a y-axis is a
horizontal axis orthogonal to said x-axis with a positive x
direction towards said crown, and a z-axis being orthogonal to both
said x-axis and said y-axis with a positive z direction extending
forward, a plurality of support members extending from the crown to
the sole of the rear portion and from a back edge toward a front
edge of the rear portion, essentially perpendicular to the striking
face, a first support member being located near a central portion
of said golf club head in a heel-to-toe orientation, extending
substantially in line, along the z-axis, with said face center; and
wherein said golf club head has a MOI-Y to MOI-Z ratio of greater
than about 1.5.
2. The golf club of claim 1, wherein the first support member has a
first maximum height parallel to the y-axis, a first maximum depth
parallel to the z-axis and a first thickness and the first depth is
greater than the first maximum height and the first thickness is
between 0.5 mm and 1.5 mm.
3. The golf club of claim 2, wherein the first support member has a
plurality of angled strut members that form angles .alpha. in
between the strut members of between 30 degrees and 100
degrees.
4. The golf club of claim 2, wherein a second support member is on
a toe side of the first support member, between 20% and 70% of a
distance from the first support member and a furthest toe edge, and
a third support member is on a heel side of the first support
member, between 20% and 70% of a distance from the first support
member and a furthest heel edge.
5. The golf club of claim 4, wherein the golf club head has a CG
and a CG-C, being a distance the CG is back, parallel to the
z-axis, from the shaft axis, of between 14 mm to 21 mm.
6. The golf club of claim 5, wherein said golf club head has a
MOI-X to MOI-Z ratio of greater than about 1.20.
7. A golf club comprised of a golf club head, a shaft having a
shaft axis coupled to the golf club head at a first end of the
shaft and a grip coupled to the shaft at a second end of the shaft,
wherein the golf club head comprises: a frontal portion comprised
of metal, comprising a striking face having a face center located
at a forward portion of said golf club head; a rear portion
comprising a thermoplastic material selected from the group
consisting of polyetherimide, polyether ether ketone, polyphenylene
sulfide, polysulfone, polyacryletherketone, polyetherketoneketone
and polyvinyl chloride and located aft of said striking face
comprising a crown at an upper portion of said golf club head and a
sole on a bottom portion of said golf club head; and wherein an
x-axis is defined as a horizontal axis tangent to said face center
with a positive x direction towards a heel of said golf club head,
a y-axis is a horizontal axis orthogonal to said x-axis with a
positive x direction towards said crown of said golf club head, and
a z-axis being orthogonal to both said x-axis and said y-axis with
a positive z direction extending forward, 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 along the
z-axis with said face center; and a plurality of support members
comprising a thermoplastic material selected from the group
consisting of polyetherimide, polyether ether ketone, polyphenylene
sulfide, polysulfone, polyacryletherketone, polyetherketoneketone
and polyvinyl chloride, and extending from the crown to the sole
and from a back edge toward a front edge of the rear portion,
extending essentially perpendicular to the striking face, a first
support member being located near a central portion of said golf
club head in the heel-to-toe orientation, extending substantially
in line, along the z-axis, with said face center.
8. The golf club of claim 7, wherein said rear portion and the
plurality of support members are comprised of polyphenylene sulfide
having a crystallinity of greater than 40%.
9. The golf club of claim 7, wherein said rear portion and the
plurality of support members are comprised of polyphenylene sulfide
having a crystallinity between about 40% and 60%.
10. The golf club of claim 7, wherein said rear portion and the
plurality of support members are comprised of polyphenylene sulfide
having a crystallinity of greater than 40% and glass filler in an
amount of between about 20% and 50%.
11. A method of forming a golf club comprising the steps of:
forming a frontal portion comprised of a crown return, a sole
return and a striking face, comprised of titanium; forming a rear
portion and a plurality of support members therein by: forming a
wax rear portion with a plurality of tabs on an inner surface
thereof; forming a plurality of wax support members; coupling the
wax support members to the plurality of tabs in the wax rear
portion to form a final rear wax; and using the final rear wax to
cast the rear portion and the plurality of support members from
titanium; and welding the rear portion to the frontal portion.
Description
RELATED APPLICATIONS
[0001] The present application is a continuation-in-part of
co-pending U.S. application Ser. No. 16/780,040, filed on Feb. 3,
2020, which is a continuation-in-part of co-pending U.S.
application Ser. No. 16/539,622, filed on Aug. 13, 2019, which is a
continuation-in-part of abandoned U.S. application Ser. No.
16/219,651, filed on Dec. 13, 2018, the entirety of which are
incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The present invention relates generally to a new and
improved golf club having improved Moment of Inertia (MOI)
characteristics, combined with an improved Center of Gravity (CG)
location. 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), a 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 normal to the hosel axis
along the X-Y plane (CG-B).
BACKGROUND OF THE INVENTION
[0003] With the development of the modern day oversized metalwoods,
the performance capabilities of these types of golf clubs have
increased dramatically over their predecessor, "the persimmon
wood". One of the ways these metalwood type golf clubs have been
performing better than their predecessors is in the increase in
overall distance, generally attributed to the inherent elastic
deformation of thin metallic metal materials used by these
metalwoods. Another way the metalwood type golf clubs have been
outperforming their predecessors is in the increase in overall
forgiveness of the golf club head, generally attributed to the
increase in the MOI of the golf club head itself.
[0004] The MOI of a golf club head generally is a term used to
describe the ability of an object to resist rotational movement
upon impact with a secondary object. In the case of a golf club
head, MOI refers to the ability of the golf club head to resist
undesirable twisting upon impact with a golf ball, as such a
twisting movement will generally change the face angle of the golf
club head away from the intended target line, sending the golf ball
away from the intended target.
[0005] U.S. Pat. No. 5,354,055 to MacKeil shows one of the earliest
attempts to increase the MOI of a golf club head by placing the
Center of Gravity (CG) location rearward. U.S. Pat. No. 6,364,788
to Helmstetter et al. shows the utilization of weighting members to
help control the MOI of the golf club head. Both of these patents
refer to the MOI-y of the golf club head, as it relates to the
ability of the golf club head to stay stable when encountering an
off-center impact in the heel and toe direction.
[0006] U.S. Pat. No. 7,850,542 to Cackett et al. illustrates a
further development in the MOI research wherein a recognition of
the different axis of rotation of the different MOI's.
(Alternatively known as Ixx, Iyy, and Izz instead of MOI-X, MOI-Y,
and MOI-Z) Despite the recognition and identification of the
difference in MOI values, U.S. Pat. No. 7,850,542 only focuses its
attention on Ixx and Iyy (adapted and changes to the current
reference nomenclature), without any recognition of the importance
of the last MOI number, Izz, nor MOI-SA and how they can affect the
performance of the golf club.
[0007] Despite the above, none of the references recognizes the
importance of the MOI of the golf club head horizontally forward
and aft of the face (MOI-Z), and ways to design a golf club that
takes advantage of the performance characteristics of golf club
with more optimal MOI-Z values along with the minimized MOI-Sa
values. Moreover, a closer investigation of the MOI-Z values will
yield CG locations that will work in conjunction with the above
MOI-Z values to create more performance. Hence, it can be seen from
the above there is a need for more research and a design of a golf
club capable of achieving better performance by investigating the
importance of MOI-Z and MOI-SA as well as the CG location and
designing a golf club head.
BRIEF SUMMARY OF THE INVENTION
[0008] One aspect of the present invention is a golf club comprised
of a golf club head, a shaft coupled to the golf club head at a
first end of the shaft and a grip coupled to the shaft at a second
end of the shaft, where the golf club head comprises of a frontal
portion further comprising a striking face that defines a face
center, located at a forward portion of the golf club head; a rear
portion located aft of the striking face; and at least one
weighting member located near a central portion of the golf club
head in a heel to toe orientation, substantially in line with and
behind the 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 a frontal portion of said golf club
head, and wherein said golf club head has a MOI-Y to MOI-Z ratio of
greater than about 1.50.
[0009] In another aspect of the present invention is a golf club
head comprising of a golf club head comprising of a frontal portion
further comprising a striking face that defines a face center,
located at a forward portion of the golf club head, a rear portion
located aft of the striking face, and at least one weighting member
located near a central portion of the golf club head in a heel to
toe orientation, substantially in line with and behind the 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
horizontal 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 a frontal portion of said golf club head, and
wherein said golf club head has a MOI-X, MOI-Z, and CG-Z numbers
that satisfies the equation
MOI .times. - .times. X MOI .times. - .times. Z .gtoreq. ( 6.7501 *
CG .times. - .times. Z ) - 99.30 . ##EQU00001##
[0010] Another aspect of the present invention is a golf club head
comprising a striking face, a crown return, a sole return and a
central body member that are formed of metal. The central body
member is located near the central portion of said golf club head
in a heel to toe orientation, substantially in line along the
z-axis, and extends from the crown return and the sole return to a
back edge of said golf club.
[0011] Preferably, the golf club head is further comprised of a
heel body member made of a non-metallic material and coupled to a
heel side of the central body member and a toe body member made of
a non-metallic material and coupled to a toe side of the central
body member. The golf club head can further include two weight
members, one forward near the striking face and one aft near the
back edge. In one embodiment, a wall member is coupled to a crown
portion of the central body member and a sole portion of the
central body member and extends between the first and second weight
members.
[0012] In another embodiment, the golf club head is further
comprised of a central support member that is comprised of a
plurality of angled strut members extending form the crown to the
sole between the two weight members. Preferably, a first angled
strut member extends from a crown portion of the central body
member to the sole and a second angled strut member extends from a
sole portion of the central body member to the crown, and the first
and second angled strut members cross each other. More preferably,
the first and second angled strut members extend at an angle of
between 15 degrees and 75 degrees from both the y-axis and the
z-axis. The golf club head can further comprise a third angled
strut member that extends from a crown portion of the central body
member to the sole and a fourth angled strut member that extends
from a sole portion of the central body member to the crown, and
the third and fourth angled strut members cross each other. The
third and fourth angled strut members also extend at an angle of
between 15 degrees and 75 degrees from both the y-axis and the
z-axis, and preferably, the third angled strut member is coupled to
the first angled strut member and the fourth angled strut member is
coupled to the second angled strut member. The golf club can
further comprise a vertical strut member extending vertically,
substantially parallel to the y-axis, between the fourth angled
strut member and the third angled strut member.
[0013] These and other features, aspects and advantages of the
present invention will become better understood with reference to
the following drawings, description and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The foregoing and other features and advantages of the
invention will be apparent from the following description of the
invention as illustrated in the accompanying drawings. The
accompanying drawings, which are incorporated herein and form a
part of the specification, further serve to explain the principles
of the invention and to enable a person skilled in the pertinent
art to make and use the invention.
[0015] FIG. 1 of the accompanying drawings shows a perspective view
of a golf club head in accordance with an exemplary embodiment of
the present invention;
[0016] FIG. 2 of the accompanying drawings shows a top view of a
golf club head in accordance with an exemplary embodiment of the
present invention;
[0017] FIG. 3 of the accompanying drawings shows a frontal view of
a golf club head in accordance with an exemplary embodiment of the
present invention;
[0018] FIG. 4 of the accompanying drawings shows a plot of MOI-Z vs
MOI-Y numbers for the current invention, compared to prior art golf
club heads;
[0019] FIG. 5 of the accompanying drawings shows a plot of MOI-Z vs
MOI-Shaft Axis numbers for the current invention, compared to prior
art golf club heads;
[0020] FIG. 6 of the accompanying drawings shows a plot of MOI-Y vs
MOI-Shaft Axis numbers for the current invention, compared to prior
art golf club heads;
[0021] FIG. 7 of the accompanying drawings shows a plot of MOI-X vs
MOI-Shaft Axis numbers for the current invention, compared to prior
art golf club heads;
[0022] FIG. 8 of the accompanying drawings shows a plot of MOI-Z vs
CG-B/Face Width numbers for the current invention, compared to
prior art golf club heads;
[0023] FIG. 9 of the accompanying drawings shows a plot of MOI-Z vs
CG-B/Head Width numbers for the current invention, compared to
prior art golf club heads;
[0024] FIG. 10 of the accompanying drawings shows a plot of
MOI-X/MOI-Z vs CG-Z numbers for the current invention, compared to
prior art golf club heads;
[0025] FIG. 11 of the accompanying drawings shows a plot of
MOI-Y/MOI-Z vs CG-Z numbers for the current invention, compared to
prior art golf club heads;
[0026] FIG. 12 of the accompanying drawings shows a plot of
(MOI-X+MOI-Y)/MOI-Z vs CG-Z numbers for the current invention,
compared to prior art golf club heads;
[0027] FIG. 13 of the accompanying drawings shows an exploded sole
perspective view of a golf club head in accordance with an
exemplary embodiment of the present invention;
[0028] FIG. 14 of the accompanying drawings shows a horizontal
cross-sectional view of a golf club head in accordance with an
exemplary embodiment of the present invention;
[0029] FIG. 15 of the accompanying drawings shows a vertical
cross-sectional view of a golf club head in accordance with an
exemplary embodiment of the present invention;
[0030] FIG. 16 of the accompany drawings shows a perspective view
of a golf club head in accordance with an alternative embodiment of
the present invention;
[0031] FIG. 17 of the accompanying drawings shows a top view of a
golf club head in accordance with an alternative embodiment of the
present invention;
[0032] FIG. 18 of the accompanying drawings shows a frontal view of
a golf club head in accordance with an alternative embodiment of
the present invention;
[0033] FIG. 19 of the accompanying drawings shows a horizontal
cross-sectional view of a golf club head in accordance with an
alternative embodiment of the present invention;
[0034] FIG. 20 of the accompanying drawings shows a vertical
cross-sectional view of a golf club head in accordance with an
alternative embodiment of the present invention;
[0035] FIG. 21 of the accompanying drawings shows a top view of a
golf club head in accordance with an alternative embodiment of the
present invention;
[0036] FIG. 22 of the accompanying drawings shows a frontal view of
a golf club head in accordance with an alternative embodiment of
the present invention;
[0037] FIG. 23 of the accompanying drawings shows a top view of a
body portion of the golf club head in accordance with an
alternative embodiment of the present invention shown in FIG.
21;
[0038] FIG. 24 of the accompanying drawings shows a bottom view of
a body portion of the golf club head in accordance with an
alternative embodiment of the present invention shown in FIG.
21;
[0039] FIG. 25 of the accompanying drawings shows a vertical side
view of a body portion of a golf club head in accordance with an
alternative embodiment of the present invention;
[0040] FIG. 26 of the accompanying drawings shows a vertical side
view of a body portion of a golf club head in accordance with an
alternative embodiment of the present invention;
[0041] FIG. 27 of the accompanying drawings shows a top view of a
golf club head in accordance with an alternative embodiment of the
present invention;
[0042] FIG. 28 of the accompanying drawings shows a top view of a
body portion of the golf club head in accordance with an
alternative embodiment of the present invention shown in FIG.
27;
[0043] FIG. 29 of the accompanying drawings shows a bottom view of
a body portion of the golf club head in accordance with an
alternative embodiment of the present invention shown in FIG.
27;
[0044] FIG. 30 of the accompanying drawings shows a top view of a
body portion of the golf club head in accordance with an
alternative embodiment of the present invention shown in FIG.
27;
[0045] FIG. 31 of the accompanying drawings shows a bottom view of
a body portion of the golf club head in accordance with an
alternative embodiment of the present invention;
[0046] FIG. 32 of the accompanying drawings shows a cross-sectional
view of a first weight member shown in FIG. 31;
[0047] FIG. 33 of the accompanying drawings shows a cross-sectional
view of a second weight member shown in FIG. 31;
[0048] FIG. 34 of the accompanying drawings shows a bottom
perspective view of another embodiment of a golf club head in
accordance with the present invention;
[0049] FIG. 35 of the accompanying drawings shows a cross-sectional
view of the golf club head in accordance with an alternative
embodiment of the present invention shown in FIG. 34;
[0050] FIG. 36 of the accompanying drawings shows a close-up,
cross-sectional view of the golf club head in accordance with an
alternative embodiment of the present invention shown in FIG.
34;
[0051] FIG. 37 of the accompanying drawings shows a close-up,
cross-sectional view of the golf club head in accordance with an
alternative embodiment of the present invention shown in FIG.
34;
[0052] FIG. 38 of the accompanying drawings shows a bottom
perspective view of another embodiment of a golf club head rear
portion in accordance with the present invention;
[0053] FIG. 39 of the accompanying drawings shows a frontal view of
the golf club head rear portion in accordance with an alternative
embodiment of the present invention shown in FIG. 38;
[0054] FIG. 40 of the accompanying drawings shows a close-up,
cross-sectional view of the golf club head in accordance with an
alternative embodiment of the present invention shown in FIG. 38;
and
[0055] FIG. 41 of the accompanying drawings shows a close-up,
cross-sectional view of the golf club head in accordance with an
alternative embodiment of the present invention shown in FIG.
38;
[0056] FIG. 42 of the accompanying drawings shows a front view of
another golf club head in accordance with an embodiment of the
present invention;
[0057] FIG. 43 of the accompanying drawings shows a perspective
view of a portion of another golf club head in accordance with an
embodiment of the present invention
DETAILED DESCRIPTION OF THE INVENTION
[0058] The following detailed description describes the best
currently contemplated modes of carrying out the invention. The
description is not to be taken in a limiting sense, but is made
merely for the purpose of illustrating the general principles of
the invention, since the scope of the invention is best defined by
the appended claims.
[0059] Various inventive features are described below and each can
be used independently of one another or in combination with other
features. However, any single inventive feature may not address any
or all of the problems discussed above or may only address one of
the problems discussed above. Further, one or more of the problems
discussed above may not be fully addressed by any of the features
described below.
[0060] Before beginning the discussion on the current inventive
golf club head and its performance criteria, it is worthwhile to
note here that the discussion below will be based on a coordinate
system 101 and axis of measurement that is critical to the proper
valuation of the performance numbers. Hence, it is important to
recognize here that although the specific names given for the
measurements below are important to the understanding of the
current invention, the naming nomenclature should not be viewed in
vacuum. Rather, the importance is the numbers presented below needs
to be taken in context with how the coordinate system relates to
the golf club head itself. In order to provide sufficient
information to avoid any ambiguity, each of the figures provided
below referencing a golf club head will all be accompanied by a
coordinate system that is all consistent with one another.
[0061] Pursuant to the above, and to establish the reference
coordinate system for the subsequent discussion, FIG. 1 of the
accompanying drawings shows the coordinate system 101 that will be
used to define the various measurement and performance figures for
the current invention. The x-axis used by the current discussion
refers to the axis that is horizontal to the striking face from a
heel to toe direction. The y-axis used by the current discussion
refers to the vertical axis through the club in a crown to sole
direction. The z-axis used by the current discussion refers to the
horizontal axis that is horizontal front to back in a forward and
rear direction. Alternatively speaking, it can be the x-axis is
defined as a horizontal axis tangent to a geometric center of the
striking face with the positive direction towards a heel of the
golf club head, a y-axis is a horizontal axis orthogonal to the
x-axis with a positive direction towards a top of the golf club
head, and a z-axis being orthogonal to both the x-axis and the
y-axis with a positive direction towards a front of the golf club
head. The x-y-z coordinate system described above shall be the same
for all subsequent discussions.
[0062] FIG. 1 of the accompanying drawings shows a perspective view
of a golf club head 100 in accordance with an embodiment of the
present invention. In this perspective view shown in FIG. 1, the
golf club head 100 may not look very different than other golf club
heads, but the subsequent figures and discussion will show that the
internal components and the material properties of this golf club
head 100 allows it to achieve unique performance properties
consistent with the present invention. What FIG. 1 does show is a
location of a face center 102 of the frontal portion 104 of the
golf club head 100 that contains a striking face insert. The face
center, as shown here and referred to by the current invention,
relates to the geometric center of the striking face portion of
said golf club head 100 measured by the USGA provided face center
template as it would be commonly known to a person of ordinary
skill in the golf club art. Attached to the rear of the frontal
portion 104 is a rear portion 106, which makes up the back end of
the golf club head 100.
[0063] In this embodiment of the present invention, the frontal
portion 104 may generally be made out of a steel type material
having a density of between about 7.75 g/cc and about 8.00 g/cc,
allowing a significant portion of the mass of the golf club head
100 to be concentrated at a frontal bottom region of the golf club
head 100. The rear portion 106 of the golf club head 100 in this
embodiment of the present invention may generally be made out of
the standard titanium material having a density of between about
4.00 g/cc and about 5.00 g/cc, allowing the rear portion 106 of the
golf club head 100 to be relatively lightweight. However, it should
be noted that in alternative embodiments of the present invention,
the frontal portion 104 may also be made out of a standard titanium
material such as TI-6-4, Ti-8-1-1, beta-titanium, or any other type
of titanium material without departing from the scope and content
of the present invention.
[0064] In order to illustrate more specific features of the golf
club head 100, FIGS. 2 and 3 of the accompanying drawings is
provided to give more insight into some of the specific inherent
characteristics of the golf club head 200 that will be important to
determine its improved performance. First off, FIG. 2 of the
accompanying drawings, in addition to illustrating a golf club head
200 with a frontal portion 204 and a rear portion 206, also shows a
Center of Gravity (CG) 210 location along the x-z plane on the
coordinate system 201. Although the details of the CG location will
be discussed in more detail with respect to the inertia properties
of the golf club head 200, the general direction of the current
inventive golf club head 200 is to have a CG location that is
strategically located at a distance back from the frontal portion
of the golf club head 200 to yield the most advantageous
results.
[0065] More specifically, in the current invention, the CG location
rearward from the striking face, identified here as CG-Z is
generally between about 25 mm to about 40 mm, more preferably
between about 26 mm and about 38 mm, and most preferably between
about 27 mm and about 36 mm, all measured rearward from the face
center 202 along the Z axis shown by the coordinate system 201. In
addition to illustrating the CG-Z 212 numbers, an alternative
measurement method is provided to measure how far back the CG 210
is located within the club head 200. In this alternative method,
the CG 210 is measured from the shaft axis 215, and this
measurement is illustrated as CG-C 214 is generally measured to be
between about 10 mm to about 25 mm, more preferably between about
12 mm to about 23 mm, and most preferably between about 14 mm to
about 21 mm, all measured rearward from the shaft axis 215 along
the Z axis shown by the coordinate system 201.
[0066] It should be noted that the strategic location of the CG 210
location rearward along the Z axis, irrespective of whether it is
measured from the face center 202 or the shaft axis 215, is
critical to the proper functionality of the current inventive golf
club head 200. If the CG 210 location is too far forward, the golf
club head 200 can result in a low MOI-X and MOI-Y as well as too
low of a backspin when contacting a golf ball to yield desirable
results. However, in the alternative, if the CG 210 location is too
far rearward, the golf club head 200 can produce too much spin to
yield desirable results. Hence, it can be seen that the criticality
of the CG location rearward of along the Z axis is a fine balance
of a very specific range of numbers that can severely hinder the
performance of the golf club head 200 if it deviates from the
ranges articulated above.
[0067] FIG. 3 of the accompanying drawings shows another important
CG 210 measurement that is important to the proper functionality of
the current invention. More specifically, FIG. 3, in addition to
illustrating all of the basic components of the golf club head 200
as previously shown, now introduces another measurement of the CG
210 location from the shaft axis 215 along an x-y plane shown by
coordinate system 301. More specifically, FIG. 3 shows a CG 210
measurement that is perpendicular to the shaft axis 215 along this
x-y plane away from the actual shaft axis 215 itself, called CG-B
for the purpose of this application. The CG-B of the golf club head
210 may generally be between about 32 mm and about 39 mm, more
preferably between about 33 mm and about 38 mm, and most preferably
about 35 mm.
[0068] In addition to illustrating the very important CG-B
measurement of the golf club head, FIG. 3 of the accompanying
drawings also shows measurements W1 and W2, indicative of the width
of the golf club head 200 itself and the width of the face of the
golf club head 200 respectively. In this embodiment of the present
invention, the width of the golf club head W1 may generally be
between about 130 mm to and about 140 mm, more preferably between
about 132 mm to about 138 mm, and most preferably about 136 mm. The
width of the face W2 may generally be between about 95 mm and about
105 mm, more preferably between about 97 mm and about 103 mm, and
most preferably about 100 mm.
[0069] Now that the CG location of the golf club head 200 has been
defined, the other important features associated with the present
invention relates to the Moment of Inertia (MOI) of the golf club
head 200. The MOI of a golf club head generally depicts the ability
of the golf club head to resist twisting when it impacts an object
at a location that is not aligned with the CG location previously
discussed. More specifically, the MOI of a golf club head relates
to the ability of the golf club head to resist twisting relative to
the CG location. The MOI of the golf club head 200 may generally be
broken down to three unique components, relating to the ability of
the golf club head 200 to resist rotation along three different
axes. The three axes of rotation for which the MOI is generally
referred coincides with the coordinate system 101, 201, and 301
(shown in FIG. 1, FIG. 2, and FIG. 3 respectively).
[0070] As the previously discussion already hinted, the current
inventive golf club head 200 may generally have a high value for
the MOI about the X and Y axis, while maintaining a low MOI about
the Z axis. More specifically, the current inventive golf club head
200 may generally have a MOI about the X axis (MOI-X) that is
greater than about 300 kg-mm.sup.2, more preferably greater than
about 310 kg-mm.sup.2, and most preferably greater than about 320
kg-mm.sup.2 without departing from the scope and content of the
present invention. As for MOI about the Y axis (MOI-Y), the present
inventive golf club head 200 may generally have a MOI about the Y
axis that is greater than about 400 kg-mm.sup.2, more preferably
greater than about 410 kg-mm.sup.2, and most preferably greater
than about 420 kg-mm.sup.2 all without departing from the scope and
content of the present invention.
[0071] While the large MOI number about the X and Y axis discussed
previously are not necessarily new in the world of golf club head
200 designs, the ability to maintain those number while decreasing
the MOI about the Z axis (MOI-Z) and holding the MOI about the
Shaft axis (MOI-SA) to a minimum is what makes the present
invention. While the majority of the golf industry are focusing
their attention so intently on the ability of the golf club head
200 to offer forgiveness on off center hits by trying to increase
the MOI-Y to astronomical numbers, they have failed to recognize
the ability of the golf club head 200 to offer more club head speed
and more ball speed by decreasing the MOI about the Z axis (MOI-Z)
in concert with the minimization of MOI about the Shaft axis
(MOI-SA). The present invention focuses its attention on that very
specific unrecognized characteristic, and has developed a golf club
head 200 design to take advantage and maximize the performance of
the golf club head 200 by focusing on the MOI about the Z axis.
More specifically, a golf club head 200 in accordance with the
present invention may generally have a MOI about a Z axis that is
less than about 268 kg-mm.sup.2, more preferably less than about
260 kg-mm.sup.2, and most preferably less than about 250
kg-mm.sup.2. Additionally, the golf club head 200 may generally
have a MOI about a Shaft axis that is less than about 850
kg-mm.sup.2.
[0072] It should be noted here that the low MOI-Z numbers mentioned
above cannot by itself accurately depict and describe the current
invention; as old school golf club heads with much smaller
footprint may inherently have a low MOI-Z number, combined with a
low MOI-X and MOI-Y number. Hence, it is important to recognize
here that the present invention is predicated on the
interrelationship between the different numbers achieved by the
MOI-X and MOI-Y numbers as it relates to MOI-Z and MOI-SA, in
combination with the CG location articulated above.
[0073] In order to capture the essence of the present invention, a
ratio can be created between the MOI-X, MOI-Y, and MOI-Z to help
provide one way to quantify this relationship. In one first
example, a MOI-X to MOI-Z Ratio can be created to help quantify the
current golf club head 200 as illustrated by Eq. (1) below. In one
exemplary embodiment of the present invention, the MOI-X to MOI-Z
Ratio is greater than about 1.10, more preferably greater than
about 1.20, and most preferably greater than about 1.28.
MOI .times. - .times. X .times. .times. to .times. .times. MOI
.times. - .times. Z .times. .times. Ratio = MOI .times. - .times. X
MOI .times. - .times. Z Eq . .times. ( 1 ) ##EQU00002##
Similarly, a comparable ratio can be established called a MOI-Y to
MOI-Z Ratio to quantify the current golf club head 200 as
illustrate by Eq. (2) below. In one exemplary embodiment of the
present invention, the MOI-Y to MOI-Z ratio is greater than about
1.50, more preferably greater than about 1.57, and most preferably
greater than about 1.68.
MOI .times. - .times. Y .times. .times. to .times. .times. MOI
.times. - .times. Z .times. .times. Ratio = MOI .times. - .times. Y
MOI .times. - .times. Z Eq . .times. ( 2 ) ##EQU00003##
[0074] As it can be seen from the relationship established by the
Eqs (1) and (2) above, the present invention relates to a specific
relationship between the MOI of the golf club head 200 with an
extra focus on minimizing the MOI-Z about the Z axis while
maintaining a high MOI-Y. In order to further illustrate this, a
graphical representation of the relationship is provided as FIG.
4.
[0075] FIG. 4 of the accompanying drawings shows a plot of various
data points of various golf club head and their respective MOI-Z
numbers as well as their MOI-Y number. In FIG. 4 the X-axis
represents the MOI-Y while the Y-axis represents the MOI-Z. The
data points shown in FIG. 4 have been separated into circular dots
and asterisks. The circular dots are representative of the data of
"prior art" golf club heads, whereas the asterisk data points
represent the current invention.
[0076] A closer examination of the prior art data points will show
that none of the golf club heads in the prior art are capable of
achieving a MOI-Z number of lower than 268 kg-mm.sup.2, for all
modern day golf club heads that have a MOI-Y of greater than 420
kg-mm.sup.2. However, an even closer examination of the graph of
FIG. 4 will show that as the MOI-Y numbers of the golf club heads
exceeds 500 kg-mm.sup.2, an additional relationship can be
established to quantify the ability of the present invention to
achieve the optimal MOI-Z to MOI-Y relationship. In fact, that
relationship is shown in FIG. 4 as Y.ltoreq.0.47x+33. Combining the
two conditions articulated above can result in another unique way
to quantify the present invention whereas, for golf club heads
having a MOI-Y of between 420 kg-mm.sup.2 and 500 kg-mm.sup.2, the
golf club head generally has a MOI-Z of less than about 268;
however, for golf club heads having a MOI-Y of greater than 500
kg-mm.sup.2, the golf club head may have a MOI-Z that satisfies Eq.
(3) below:
MOI-Z.ltoreq.(0.47*MOI-Y)+33 Eq. (3)
[0077] Alternatively speaking, it can be said that in one
embodiment of the present invention, the golf club head 200 may
have a MOI-Z that satisfies the relationship
MOI-Z.ltoreq.(0.47*MOI-Y)+33 if the MOI-Y number is greater than
500 kg-mm.sup.2, and a MOI-Z that is less than 268 kg-mm.sup.2 if
the MOI-Y number is between 420 kg-mm.sup.2 and 500
kg-mm.sup.2.
[0078] FIG. 5 of the accompanying drawing introduces another MOI
value relating to a golf club head not previously discussed named
MOI-Shaft Axis (MOI-SA). The MOI of a golf club head as it relates
to the shaft axis is defined as the ability of the golf club head
to resist twisting upon impact with a golf ball at a location that
is not aligned with the shaft axis. A golf club head in accordance
with the present invention may generally have a MOI-SA of less than
about 850 kg-mm.sup.2, more preferably less than about 800
kg-mm.sup.2, and most preferably less than about 750 kg-mm.sup.2.
The relationship between the MOI-SA and MOI-Z is highlighted in
FIG. 5 and is important to the present invention. FIG. 5 of the
accompanying drawings shows that irrespective of the MOI-SA
numbers, all of the prior art golf club heads have a MOI-Z of
greater than about 268 kg-mm.sup.2, while all of the current
inventive golf club heads have a MOI-Z of less than about 268
kg-mm.sup.2.
[0079] FIG. 6 of the accompanying drawings establishes a graphical
relationship between the MOI-Y of the golf club head with the newly
introduced MOI-SA. As a closer examination of the graph shown in
FIG. 6 will show, the current invention is capable of achieving a
higher than average MOI-Y, all while keeping a relatively small
MOI-SA. Similar to previous plots, the circular points on the plot
will refer to prior art golf club heads, while the asterisks will
refer to the current invention. Hence, it can be seen that the
present invention occupies a previously unachieved space delineated
by an equation Y.gtoreq.0.52x+147, which when put into context with
the variables used in this plot, yields Eq. (4) below:
MOI-Y.gtoreq.(0.52*MOI-SA)+147 Eq. (4)
[0080] FIG. 7 of the accompanying drawings establishes a graphical
relationship between the MOI-X of the golf club head with now a
familiar MOI-SA. As a closer examination of the graph shown in FIG.
7 will show, the current invention is capable of achieving a higher
than average MOI-X, all while keeping a relatively small MOI-SA.
Hence, it can be seen that the present invention occupies a
previously unachieved space delineated by an equation
Y.gtoreq.0.40x+50, which when put into context with the variables
used in this plot, yields Eq. (5) below:
MOI-X.gtoreq.(0.40*MOI-SA)+50 Eq. (5)
[0081] FIG. 8 of the accompanying drawings establishes a graphical
relationship between the MOI-Z of the golf club head with a ratio
of CG-B/Face Width. Both the measurement for CG-B and Face Width
can be found in FIG. 3 of the accompanying drawings as well as the
accompanying discussion in paragraphs [0022] and [0023]. The CG-B
measurement is explicitly shown in FIG. 3, while the Face Width
referred to by the chart in FIG. 8 is shown as W2. A closer
examination of the graph shown in FIG. 8 will show that the current
invention is capable of achieving a lower MOI-Z, while keeping the
CG-B/Face Width number fairly consistent above 0.4. CG-B/Face Width
is indicative of the location of the center of gravity while
keeping a moderately sized face golf club head.
[0082] In the chart shown in FIG. 8, it can be seen that the
present invention occupies a previously unachieved space delineated
by an equation Y.ltoreq.1000x-150, which when put into context with
the variable used in this plot, yields Eq. (6) below:
.times. MOI .times. - .times. Z .ltoreq. ( 1000 * CG .times. -
.times. B Face .times. .times. Width ) - 150 Eq . .times. ( 6 )
##EQU00004##
[0083] FIG. 9 of the accompanying drawings establishes a graphical
relationship between the MOI-Z of the golf club head with a ratio
of CG-B/Head Width. Both the measurement for CG-B and Head Width
can be found in FIG. 3 of the accompanying drawings as well as the
accompanying discussion above in paragraph [0022] and [0023]. The
CG-B measurement is explicitly shown in FIG. 3, while the Head
Width referred to by the chart in FIG. 9 is shown as W1. A closer
examination of the graph shown in FIG. 9 will show that the current
invention is capable of achieving a lower MOI-Z, while keeping the
CG-B/Head Width number fairly consistent above 0.34. CG-B/Head
Width is indicative of the location of the center of gravity while
keeping a moderately sized head width of the golf club head.
[0084] In the chart shown in FIG. 9, it can be seen that the
present invention occupies a previously unachieved space delineated
by a MOI-Z number that is lower than 320 kg-mm.sup.2 combined with
a CG-B/Head Width number that is greater than about 0.34.
[0085] FIG. 10 of the accompanying drawings establishes another
graphical relationship of the performance of a golf club in
accordance with an embodiment of the present invention. More
specifically, FIG. 10 of the accompanying drawings shows a
relationship between MOI-X/MOI-Z and CG-Z. (MOI-X is used
interchangeably with Ixx, MOI-Y is used interchangeably with Iyy,
and finally MOI-Z is used interchangeably with Izz) The definition
and measurement for CG-Z of a golf club head can be found in the
earlier discussion relating to FIG. 2 of the accompanying drawings,
while the background information establishing MOI-X and MOI-Z have
already been discussed previously. Although the selection of the
plot for the X and Y axis may appear random initially to a person
not versed in golf club design, but a closer examination will
reveal that the relationship created here is absolutely critical to
the proper performance of the present invention. On the Y axis of
the plot shown in FIG. 10, a ratio between MOI-X and MOI-Z is
created here. This ratio created illustrates the ability of the
current inventive golf club head to maximize the value of one
variable (MOI-X) while minimizing the value of another variable
(MOI-Z); which resonates with the theme of the present invention.
The MOI-Z used in the X axis of the plot shown in FIG. 10 is
indicative of the CG location of the golf club head rearward from
the front of the golf club head, and it is desirable to maintain
that in the range described above.
[0086] A further examination of the plot shown in FIG. 10 will show
that the present invention occupies a portion of the graph that was
previously unachieved. This portion of the graph is delineated from
other prior art data points by an equation Y.gtoreq.6.7501x-99.3,
which when put into context with the variable used in this plot,
yields Eq. (7) below:
MOI .times. - .times. X MOI .times. - .times. Z .gtoreq. ( 6.7501 *
CG .times. - .times. Z ) - 99.30 Eq . .times. ( 7 )
##EQU00005##
[0087] FIG. 11 of the accompanying drawings establishes another
graphical relationship of a golf club in accordance with an
embodiment of the present invention by creating a relationship
between the MOI-Y/MOI-Z and CG-Z. The definition and measurement
for CG-Z of a golf club head can be found in the earlier discussion
relating to FIG. 2 of the accompanying drawings, while the
background information establishing MOI-Y and MOI-Z have already
been discussed previously. Similar to the previous discussion, the
relationship between MOI-Y and MOI-Z is indicative of the ability
of a golf club to achieve great forgiveness along the MOI-Y axis,
while minimizing the MOI-Z of a golf club head to achieve a higher
ball speed, as previously discussed. Similar to previous
discussion, FIG. 11 of the accompanying drawings shows that the
present invention is capable of achieving performance
characteristics that was previously unachieved. This portion of the
graph is delineated from other prior art data points by an equation
Y.gtoreq.11.349 x -175.76, which when put into context with the
variable used in this plot, yields Eq. (8) below:
MOI .times. - .times. Y MOI .times. - .times. Z .gtoreq. ( 11.349 *
CG .times. - .times. Z ) - 175.76 Eq . .times. ( 8 )
##EQU00006##
[0088] FIG. 12 of the accompanying drawings establishes another
graphical relationship of a golf club in accordance with an
embodiment of the present invention by creating a relationship
between the (MOI-X+MOI-Y)/MOI-Z and CG-Z. The definition and
measurement for CG-Z of a golf club head can be found in the
earlier discussion relating to FIG. 2 of the accompanying drawings,
while the background information establishing MOI-X, MOI-Y, and
MOI-Z have already been discussed previously. Similar to the
previous discussion, the relationship between MOI-X, MOI-Y, and
MOI-Z is indicative of the ability of a golf club to achieve great
forgiveness along both the MOI-X and MOI-Y axes, while minimizing
the MOI-Z of a golf club head to achieve a higher ball speed, as
previously discussed. Similar to previous discussion, FIG. 12 of
the accompanying drawings shows that the present invention is
capable of achieving performance characteristics that was
previously unachieved. This portion of the graph is delineated from
other prior art data points by an equation Y.gtoreq.18.67 x-296.63,
which when put into context with the variable used in this plot,
yields Eq. (9) below:
( MOI .times. - .times. X + MOI .times. - .times. Y ) MOI .times. -
.times. Z .gtoreq. ( 18.67 * CG .times. - .times. Z ) - 296.63 Eq .
.times. ( 9 ) ##EQU00007##
[0089] FIGS. 13 through 15 show different exploded and
cross-sectional view of golf club heads and their internal
components that are used to achieve the performance characteristics
described above. FIG. 13 shows an exploded perspective view of an
exemplary design of a golf club head 1300 in capable of achieving
the performance characteristics previously discussed. The golf club
head 1300 is made out of the essential components previously
discussed in FIG. 1 in terms of a frontal portion 1304 and a rear
portion 1306. However, this exploded view of golf club head 1300
allows additional components to be shown in more detail. More
specifically, FIG. 13 illustrates that, as often the case in a golf
club head construction, the frontal portion 1302 may further be
comprised out of a separate component called the striking face
insert 1320 to form the striking portion of the golf club head
1300. The rear portion 1306 of the golf club head 1300 is where it
gets more interesting. In order to achieve the performance numbers
above of a higher MOI-Y, a higher MOI-X, and a lower MOI-Z, a
significant amount of mass is re-allocated towards the center of
the golf club head away from the perimeter. In order to achieve
this, the present invention utilizes four weighting members that
are all comprised out of a high density material that have a higher
density than the frontal portion 1302 or the rear portion 1306. The
four weighting members can be separated into a frontal sole weight
1322, frontal internal weight 1324, rear internal weight 1326, and
rear sole weight 1328, and these weighting members may all
generally have a material density of greater than 13 g/cc, more
preferably greater than about 15 g/cc, and most preferably greater
than or about 17 g/cc.
[0090] It should be noted that in this exemplary embodiment of the
present invention, all of the weighting members 1322, 1324, 1326,
and 1328 are all made out of the same material having the same
heavy density discussed previously. However, in alternative
embodiments of the present invention, different densities of
tungsten may be used for different weighting members depending on
the design criteria and desired CG location all without departing
from the scope and content of the present invention.
[0091] FIG. 14 of the accompanying drawings shows a cross-sectional
view of a golf club head 1400 in accordance with an exemplary
embodiment of the present invention. The cross-sectional view of
the golf club head taken across a horizontal plane across the face
of the golf club head 1400 to allow some of the relationship
between the golf club head 1400 and the various weighting member
1422, 1424, 1426, and 1428 to be shown more clearly. In addition to
the weighting members, the cross-sectional view of the golf club
head 1400 shown in FIG. 14 also allows the face center 1402 and the
CG location 1410 to be re-introduced as it relates to the weighting
members. It can be seen from this view that at least one weighting
member is located near a central portion of the golf club head in a
heel to toe direction, and substantially in line with and behind
said face center.
[0092] FIG. 15 of the accompanying drawings shows a cross-sectional
view of a golf club head 1500 in accordance with an exemplary
embodiment of the present invention taken along a vertical plane
that passes through the center of the face. This cross-sectional
view of the golf club head 1500 shown in FIG. 15 provides a little
more information on the interworking relationship between the
components. More specifically, FIG. 15 shows a striking face insert
1520 being located in the frontal portion 1504 of the golf club
head 1500. In addition to the above, FIG. 15 also shows that the
frontal sole weight 1522 is located in a receptacle that is created
within the frontal portion 1504. Although not shown in this
cross-sectional view in FIG. 15, the frontal internal weight is
also located in the frontal portion 1504. Attached to the rear of
the frontal portion 1504 is the rear portion 1506. The rear portion
1506 forms the aft body portion of the golf club head 1500, and
contains the rear internal weight 1526 and the rear sole weight
1528. These weighting members, combined with the unique materials
used to form the frontal portion 1504 and the rear portion 1506,
allow the golf club head 1500 to achieve the unique performance
characteristics outlined previously.
[0093] FIGS. 16 through 20 show various perspective and
cross-sectional views of a golf club head 1600 in accordance with
an alternative embodiment of the present invention that is capable
of achieving the performance goals previously mentioned. Similar to
the previous embodiment illustrated by FIGS. 1-3 and 13-15, a lot
of weighting member is located near the center of the golf club
head 1600 in a heel to toe orientation along the x-axis behind the
face center 1602 to help minimize the MOI-Z of the golf club head
1600.
[0094] More specifically, FIG. 16 of the accompanying drawings
shows a perspective view of a golf club head 1600 in accordance
with this alternative embodiment of the present invention. Although
not much can be gleamed from this perspective view of the golf club
head 1600, it does lay the ground work for the subsequent
discussion relating to this particular embodiment of the present
invention. Finally, FIG. 16, similar to previous figures that
illustrate a golf club head, provides a coordinate system 1601 to
guide the subsequent discussions.
[0095] FIG. 17 of the accompanying drawings shows a top view of a
golf club head 1600 in accordance with this alternative embodiment
of the present invention. In this top view, a couple of familiar
dimensions are reintroduced here. First and foremost, the top view
of the golf club head 1600 shown in FIG. 17 allows the relationship
between the face center 1602 and the CG 1610 to be shown in more
detail. When measured along the Z-axis, the measurement CG-Z is
shown as 1612. The location of the CG, when referenced against the
shaft axis 1615 yields another way to measure the CG location along
the Z-axis called CG-C 1614. The number ranges for the CG-Z 1612
and CG-C 1614 measurements are not much different from previous
discussions, but this embodiment of the present invention provides
an alternative way to achieve those targets with a slightly
different construction without the need for a multi-material
chassis.
[0096] FIG. 18 of the accompanying drawings shows a frontal view of
a golf club head 1600 in accordance with this alternative
embodiment of the present invention. In this frontal view, we can
see another feature utilized by the present embodiment to help
achieve the performance criteria of the current invention. More
specifically, FIG. 18 shows that in this embodiment of the present
invention, in order to minimize the MOI-Z of the golf club head
1600, weight is removed from the extremities of the golf club head
1600 via a reshaping of the contour at the toe portion of the golf
club head 1600. This reshaping of the contour at the toe portion of
the golf club head 1600 not only removes weight from the
extremities, but also tightens up the face profile of the golf club
head 1600 to create a unique performing golf club head 1600.
[0097] In addition to illustrating this toe contour profiling, FIG.
18 also shows a CG-B 1616 measurement relating to the shaft axis
1615 similar to the previous discussion. Once again, the CG-B 1616
measurement range is in line as the previous discussion have
mentioned, and does not deviate much from the design intent of the
present invention.
[0098] FIG. 19 of the accompanying drawings shows a cut open
cross-sectional view of a golf club head 1600 in accordance with
this alternative embodiment of the present invention taken along a
horizontal plane. In this embodiment of the present invention, the
overarching theme of placing the weights along the central portion
of the golf club head 1600 reemerges again. More specifically, the
golf club head 1600 further comprises of a frontal internal weight
1624 and a rear internal weight 1626. These weights, however,
different from prior embodiments of the present invention in that
they can be made out of the same material as the body portion of
the golf club head 1600 such as titanium and be directly cast into
the body without departing from the scope and content of the
present invention. These weighting members 1624 and 1626 may also
be made out of a tungsten type material having a total weight of
20-23 grams to further improve the performance of the golf club
head 1600 without departing from the scope and content of the
present invention.
[0099] FIG. 20 of the accompanying drawings provides another
cross-sectional cut open view of the golf club head 1600 in
accordance with an alternative embodiment of the present invention
taken along a vertical plane. Once again, the measurements here are
very similar to the discussion previously relating to prior
embodiments and the CG-Z 1612 number remain within the same range
as the prior discussion. This cross-sectional cut open view of the
golf club head 1600 taken along this line allows the profile and
geometry of the frontal internal weight 1624 and the rear internal
weight 1626 to be shown more clearly and their relationship
together with the body portion of the golf club head 1600.
[0100] Referring to FIGS. 21-25 the golf club head 2000 has all of
the mass and inertial properties discussed above. Further, the golf
club head 2000 comprises frontal portion comprising a striking face
2001 having a face center FC, a crown on the upper portion of the
golf club head 2000 and a sole on the bottom portion of the golf
club head 2000. The golf club head 2000 further comprises a crown
return 2002 and a sole return 2003 as part of the frontal portion
and a central body member 2004 that are all formed of metal. The
central body member 2004 is located near the central portion of the
golf club head 2000 in a heel-to-toe orientation, substantially in
line along the z-axis as set forth above, and extends from the
crown return 2002 and the sole return 2003 to a back edge 2005 of
the golf club head. The golf club head 2000 is further comprised of
a heel body member 2006 made of a non-metallic material and coupled
to a heel side of the central body member 2004 and the crown return
2002 and the sole return 2003. The golf club head 2000 also
includes a toe body member 2007 made of a non-metallic material and
coupled to a toe side of the central body member 2004 and the crown
return 2002 and the sole return 2003. The heel body member 2006 and
the toe body member 2007 are essentially taco shell shaped,
taco-shaped, in that they form a portion of the crown and a portion
of the sole such that they have a c-shaped cross section.
Preferably, as set forth above, the metal portions can be formed of
a standard titanium materials such as TI-6-4, Ti-8-1-1,
beta-titanium, and others that have a specific gravity of about 4
g/cc to 5 g/cc. Alternatively, the metal portions can be formed of
a standard steel materials that have a specific gravity of about 7
g/cc to 9 g/cc The heel body member 2006 and the toe body member
2007 are preferably formed of a standard composite fiber composite
laminate, chopped fiber composite generally referred to as
fiber-reinforced plastic (FRP), or a composite material such as
those disclosed in U.S. Publication No. 2015-0360094, which is
incorporated by reference in its entirety herein. Alternatively,
the heel body member 2006 and the toe body member 2007 are
preferably formed of structural material having a density of less
than 3.0 g/cc such as a thermoplastic material such as those
disclosed in U.S. application Ser. No. 16/528,210, filed on Jul.
31, 2019, which is incorporated by reference in its entirety
herein, polyetherimide (PEI), polyether ether ketone (PEEK),
polyphenylene sulfide (PPS), polysulfone (PSU), polyaryletherketone
(PEAK), polyetherketoneketone (PEKK) and polyvinyl chloride (PVC).
The heel body member 2006 and the toe body member 2007 are
preferably formed by compression molding, injection molding or 3D
printing.
[0101] The golf club head 2000 further has a center of gravity CG
that is located a distance back from the face center, CG-z, a
vertical distance up from the ground plane, CG-y, a perpendicular
distance from the shaft axis, GC-SA, a horizontal distance from the
face center toward the heel side, CG-x and a distance back,
parallel to the z-axis, from the shaft axis, CG-C. As stated above,
in the current invention, the CG-z is generally between about 25 mm
to about 40 mm, more preferably between about 26 mm and about 38
mm, and most preferably between about 27 mm and about 36 mm, all
measured rearward from the face center FC along the z-axis shown by
the coordinate system above. In addition to the CG-z numbers, an
alternative measurement method is provided to measure how far back
the CG is located within the club head 2000. In this alternative
method, the CG is measured from the shaft axis SA, and this
measurement is illustrated as CG-C is generally measured to be
between about 10 mm to about 30 mm, preferably 10 mm to 25 mm, more
preferably between about 12 mm to about 28 mm, and more preferably
12 mm to 23 mm and most preferably between about 14 mm to about 21
mm, all measured rearward from the shaft axis SA along the z-axis
direction shown by the coordinate system above.
[0102] As stated above, it is important that the strategic location
of the CG rearward along the z-axis be correct, irrespective of
whether it is measured from the face center FC or the shaft axis
SA, for the proper functionality of the current inventive golf club
head 2000. If the CG location is too far forward, the golf club
head 2000 can have a low MOI-X and MOI-Y and low backspin when
contacting a golf ball. However, in the alternative, if the CG
location is too far rearward, the golf club head 2000 can produce
too much spin to yield desirable results. Hence, the CG location
rearward along the z-axis is important for the performance of the
golf club head 2000.
[0103] FIG. 22 of the accompanying drawings shows another important
CG measurement that is important to the proper functionality of the
current invention. More specifically, FIG. 22, in addition to
illustrating all of the components of the golf club head 2000 as
previously discussed, shows another measurement of the CG location
from the shaft axis SA along an x-y plane. More specifically, FIG.
22 shows a CG measurement that is perpendicular to the shaft axis
SA along this x-y plane, called CG-B for the purpose of this
application. The CG-B of the golf club head 2000 may generally be
between about 32 mm and about 39 mm, more preferably between about
33 mm and about 38 mm, and most preferably about 35 mm.
[0104] As shown in FIG. 22, the golf club head 2000 can further
include a central support member 2010 such as wall member 2010 that
is coupled to a crown portion of the central body member 2004 and a
sole portion of the central body member 2004. The wall member 2010
preferably has a thickness t that is between 0.2 mm and 5 mm, and
more preferably, between about 0.4 mm and 2 mm.
[0105] As shown in FIG. 23, the central body member 2004 preferably
has a heel side circumferential attachment edge 2011 and a toe side
circumferential attachment edge 2012 for coupling the heel body
member 2006 and the toe body member 2007, respectively, to the
central body member 2004 and the crown return 2002 and the sole
return 2003. The heel side circumferential attachment edge 2011 and
the toe side circumferential attachment edge 2012 preferably extend
from approximate the crown return 2002 and the sole return 2003 to
a back edge 2005 of the golf club head 2000.
[0106] As shown in FIG. 24, the golf club head 2000 can further
include at least one weight member 2008 or 2009, and more
preferably, includes two weight members 2008 and 2009. The first
weight member 2008 is located on the sole portion of the club head,
forward near the striking face 2001 and the second weight member
2009 is located on the sole portion of the club head, aft near the
back edge 2005. At least one of the weight members 2008 and 2009
may generally have a material density of greater than 13 g/cc, and
more preferably greater than about 15 g/cc. The weight members 2008
and 2009 preferably have a mass of between about 0 grams and 50
grams, more preferably between about 3 grams and 35 grams and most
preferably between 5 grams and 25 grams. In one embodiment of the
invention, the first weight member 2008 has a mass of at least two
times the mass of the second weight member 2009. In another
embodiment of the invention, the first weight member 2008 has a
mass of less than half the mass of the second weight member 2009.
More preferably, the weight members 2008 and 2009 are
interchangeable so that the CG can be adjusted forward and rearward
to control the club head's launch and spin characteristics.
Furthermore, the center of the first weight member 2008 is
preferably located less than 30 mm from the striking face 2001
along the z-axis and the center of the second weight member 2009 is
preferably located less than 20 mm from the back edge 2005 along
the z-axis such that the interchangeable weights can have a maximum
effect on the spin and launch characteristics of the club head.
[0107] In one embodiment of the present invention and as shown in
FIG. 25, the central support member or wall member 2010 is coupled
to a crown portion of the central body member 2004 and a sole
portion of the central body member 2004 and extends between the
first and second weight members 2008 and 2009. The central support
member 2010 preferably has a maximum height H parallel to the
y-axis and a maximum depth D parallel to the z-axis. The depth D is
preferably greater than the maximum height H. Also shown in FIG.
25, the heel side circumferential attachment edge 2011 and the toe
side circumferential attachment edge 2012 for coupling the heel
body member 2006 and the toe body member 2007 to the central body
member 2004 can include a plurality of recesses or apertures 2013
that adhesive can enter into and better lock the components
together. Alternatively, the heel side circumferential attachment
edge 2011 and the toe side circumferential attachment edge 2012 may
have a plurality of protrusions on the outer surface to create a
gap between the heel body member 2006 and the toe body member 2007
to the central body member 2004 such that an adhesive can fill the
gap and create a stronger bond therebetween.
[0108] In another embodiment of the present invention as shown in
FIG. 26, the golf club head's central support member 2010 can be
comprised of a plurality of strut members 2014, 2015, 2016, 2017,
2018 and 2019 that extend form the crown to the sole of the central
body member 2004 between the two weight members 2008 and 2009.
Again, the central support member 2010 preferably has a maximum
height H parallel to the y-axis and a maximum depth D parallel to
the z-axis. The depth D is preferably greater than the maximum
height H. Preferably, a first angled strut member 2014 extends from
a crown portion of the central body member 2004 to the sole and a
second angled strut member 2015 extends from a sole portion of the
central body member 2004 to the crown, and the first and second
angled strut members 2014 and 2015 preferably cross each other.
Preferably, the first and second angled strut members 2014 and 2015
extend at an angle .alpha. of between 15 degrees and 75 degrees
from the y-axis and an angle .beta. of between 15 degrees and 75
degrees from the z-axis. More preferably, the first and second
angled strut members 2014 and 2015 extend at an angle .alpha. of
between 15 degrees and 45 degrees from the y-axis and an angle
.beta. of between 45 degrees and 75 degrees from the z-axis. The
golf club head 2000 can further comprise a third angled strut
member 2016 that extends from a crown portion of the central body
member 2004 to the sole and a fourth angled strut member 2017 that
extends from a sole portion of the central body member 2004 to the
crown, and the third and fourth angled strut members cross each
other. The third and fourth angled strut members also extend at
angles .alpha. and .beta. of between 15 degrees and 75 degrees from
both the y-axis and the z-axis respectively. Preferably, the third
angled strut member 2016 is coupled to the first angled strut
member 2014 at the crown and the fourth angled strut member 2017 is
coupled to the second angled strut member 2015 at the sole.
Furthermore, preferably, the third angled strut member 2016 is
substantially parallel to the second angled strut member 2015 and
the fourth angled strut member 2017 is substantially parallel to
the first angled strut member 2014. The golf club head 2000 can
further comprise a vertical strut member 2018 extending vertically,
substantially parallel to the y-axis, between the first angled
strut member 2014 and the second angled strut member 2015
approximate the first weight member 2008. Even more preferably, the
golf club head 2000 can further comprise a second vertical strut
member 2019 extending vertically, substantially parallel to the
y-axis, between the fourth angled strut member 2017 and the third
angled strut member 2016 adjacent to the second weight member
2009.
[0109] The advantage of the central support member 2010, either in
the form of the wall member 2010 or the angled strut members 2014,
2015, 2016 and 2017 is that it prevents the crown portion of the
central body member 2004 from deflecting relative to the sole
portion of the central body member 2004 in the y-axis and also
prevents the portions from shearing with respect to each other in
the z-axis.
[0110] The advantage of multiple weight members 2008 and 2009 is
that the weight members can have equal mass, for example between 10
and 15 grams each, such that the CG of the club head 2000 is in a
neutral position. However, the weight members 2008 and 2009 can
also be comprised of a heavy weight, for example greater than 15
grams, and a light weight, for example less than 10 grams, such
that the CG can be moved forward or back depending on the placement
of the weights. With the heavy weight located in the aft weight
member 2009, the MOI-Y is increased and is preferably greater than
about 450 kg-mm.sup.2. Thus, in a preferred golf club head 2000,
the MOI-Y is greater than or equal to approximately 2 times the
MOI-Z. Conversely, when the heavy weight is in the forward weight
member 2008, the CG-C can be significantly decreased. For example,
a preferred golf club head 2000 can have a GC-C of between 14 mm to
21 mm.
[0111] The advantages of the club head 2000 discussed above can
also apply to fairway woods and hybrids. In those embodiments, it
is understood that the numerical values for the club properties
will be lower and the metal will be generally steels and high
strength steels known in the art. However, the construction of the
golf club head 2000 can be easily applied to these smaller
heads.
[0112] Referring to FIGS. 27-29 the golf club head 2000 has all of
the mass and inertial properties discussed above. Further, the golf
club head 2000 comprises frontal portion comprising a variable
thickness striking face 2001 having a maximum thickness at the face
center FC, a crown on the upper portion of the golf club head 2000
and a sole on the bottom portion of the golf club head 2000. The
golf club head 2000 further comprises a crown return 2002 and a
sole return 2003 adjacent the striking face 2001 as discussed above
and a central body member 2004 that are all formed of metal. The
central body member 2004 is located near the central portion of the
golf club head 2000 in a heel-to-toe orientation, substantially in
line along the z-axis as set forth above, and extends from the
crown return 2002 and the sole return 2003 to a back edge 2005 of
the golf club head 2000. As discussed above, the golf club head
2000 is further comprised of a heel body member 2006 made of a
non-metallic material and coupled to a heel side of the central
body member 2004 along the heel edge 2011 and a toe body member
2007 made of a non-metallic material is coupled to a toe side of
the central body member 2004 along the toe edge 2012. The central
body member 2004 can include a plurality of protrusions 2013a that
create an adhesive filled gap and better lock the components
together. The heel body member 2006 and the toe body member 2007
are essentially taco shell shaped, taco-shaped, in that they form a
portion of the crown and a portion of the sole such that they have
a c-shaped cross section. Preferably, as set forth above, the metal
portions can be formed of a standard titanium materials such as
TI-6-4, Ti-8-1-1, beta-titanium, and others that have a specific
gravity of about 4 g/cc to 5 g/cc. The heel body member 2006 and
the toe body member 2007 are preferably formed of a standard
composite fiber composite laminate, chopped fiber composite
generally referred to as fiber-reinforced plastic (FRP), or a
composite material such as those disclosed in U.S. Publication No.
2015-0360094, which is incorporated by reference in its entirety
herein. Alternatively, the heel body member 2006 and the toe body
member 2007 are preferably formed of a thermoplastic material such
as those disclosed in U.S. application Ser. No. 16/528,210, filed
on Jul. 31, 2019, which is incorporated by reference in its
entirety herein, polyetherimide (PEI), polyether ether ketone
(PEEK), polyphenylene sulfide (PPS), polysulfone (PSU),
polyacryletherketone (PEAK), polyetherketoneketone (PEKK) and
polyvinyl chloride (PVC). The heel body member 2006 and the toe
body member 2007 are preferably formed by compression molding,
injection molding or 3D printing.
[0113] In a most preferred embodiment, the heel body member 2006
and the toe body member 2007 are preferably formed from a high
crystallinity PPS, that is a PPS in which the crystallinity is
greater than 40%, and more preferably, greater than about 50% as
measured using differential scanning calorimetry (DSC) at a heating
rate of 20.degree. C./min. The crystallinity percentage can be
calculated using the following equation:
%
crystallinty=.DELTA.H.sub.sample/.DELTA.H.sub.reference.times.100
where: .DELTA.H.sub.sample is the sample melting enthalpy with
unknown crystallinity percentage and .DELTA.H.sub.reference is the
sample melting enthalpy with the known crystallinity. For PPS, 76.5
J/g may be utilized as the .DELTA.H.sub.reference.
[0114] In order to increase the crystallinity level in PPS, it is
recommended that the material be injection molded into molds that
are at a temperature of greater than 115.degree. C. and more
particularly in a mold that is between about 125.degree. C. and
135.degree. C. In the most preferred embodiment, the PPS
crystallinity is between about 50% and 70%. The material preferably
has a uniform thickness of about 0.5 mm to about 2 mm. However, in
one embodiment, the toe body member 2007 has a thickness that is
less than the thickness of the heel body member 2006. In another
embodiment, the toe body member 2007 and the heel body member 2006
vary such that they are thinnest on the crown portion and thicker
on the sole portion. In this embodiment, the crown portions of the
toe body member 2007 and the heel body member 2006 have a thickness
that is preferably between about 0.5 mm and 1 mm and the sole
portions of the toe body member 2007 and the heel body member 2006
are between about 1 mm and 2 mm thick.
[0115] The golf club head 2000 further has a center of gravity CG
that is located a distance back from the face center, CG-z, a
vertical distance up from the ground plane, CG-y, a perpendicular
distance from the shaft axis, GC-SA, a horizontal distance from the
face center toward the heel side, CG-x and a distance back,
parallel to the z-axis, from the shaft axis, CG-C. As stated above,
in the current invention, the CG-z is generally between about 25 mm
to about 40 mm, more preferably between about 26 mm and about 38
mm, and most preferably between about 27 mm and about 36 mm, all
measured rearward from the face center FC along the z-axis shown by
the coordinate system above. In addition to the CG-z numbers, an
alternative measurement method is provided to measure how far back
the CG is located within the club head 2000. In this alternative
method, the CG is measured from the shaft axis SA, and this
measurement is illustrated as CG-C is generally measured to be
between about 10 mm to about 25 mm, more preferably between about
12 mm to about 23 mm, and most preferably between about 14 mm to
about 21 mm, all measured rearward from the shaft axis SA along the
z-axis shown by the coordinate system above.
[0116] As stated above, it is important that the strategic location
of the CG location rearward along the z-axis be correct,
irrespective of whether it is measured from the face center FC or
the shaft axis SA, for the proper functionality of the current
inventive golf club head 2000. If the CG location is too far
forward, the golf club head 2000 can have a low MOI-X and MOI-Y and
low backspin when contacting a golf ball. However, in the
alternative, if the CG location is too far rearward, the golf club
head 2000 can produce too much spin to yield desirable results.
Hence, the CG location rearward along the z-axis is important for
the performance of the golf club head 2000.
[0117] As shown in FIGS. 29 and 31, the weight member 2008 has less
mass than weight member 2009 and is preferably made from steel (or
at least a material that has a lower density that the density of
weight member 2009). The first weight member 2008 can be located on
the forward portion of the sole return 2003, near the striking face
2001 and the second weight member 2009 located on the sole portion
of the golf club head 2000, aft near the back edge 2005. At least
one of the weight members 2008 and 2009 may generally have a
material density of greater than 13 g/cc, more preferably greater
than about 15 g/cc, and most preferably about 17 g/cc. Preferably,
at least one of the weight members 2008 and 2009 may generally have
a material density of greater than 2 g/cc and less than about 9
g/cc, and most preferably between about 4 g/cc and about 8 g/cc.
The weight members 2008 and 2009 preferably have a mass of between
about 0 grams and 50 grams, and more preferably between about 5
grams and 25 grams. In one embodiment of the invention, the first
weight member 2008 has a mass of at least two times the mass of the
second weight member 2009. In another embodiment of the invention,
the first weight member 2008 has a mass of less than half the mass
of the second weight member 2009. More preferably, the weight
members 2008 and 2009 are the same shape and volume such that they
are interchangeable so that the CG of the golf club head 2000 can
be adjusted forward and rearward to control the club head's launch
and spin characteristics. Furthermore, the center of the first
weight member 2008 is preferably located less than 30 mm from the
striking face 2001 along the z-axis direction and the center of the
second weight member 2009 is preferably located less than 20 mm
from the back edge 2005 along the z-axis direction such that the
interchangeable weights can have a maximum effect on the spin and
launch characteristics of the club head. More preferably, the
center of the first weight member 2008 is preferably located less
than 25 mm from the striking face 2001 along the z-axis direction
and the center of the second weight member 2009 is preferably
located less than 20 mm from the back edge 2005 along the z-axis
direction.
[0118] As shown in FIG. 32, the first weight member 2008 is
preferably releasably coupled to the sole return 2003 portion of
the golf club head 2000 by a fastener 2020. The first weight member
2008 may generally have a material density of greater than 4 g/cc,
more preferably greater than about 7 g/cc, and most preferably
between about 7 g/cc and 8 g/cc. The first weight member preferably
has a light side 2021 and a heavy side 2022. The heavy side 2022 is
preferably substantially solid and as shown in FIGS. 29 and 31 is
the side identified with indicia such as with a dot. In a preferred
embodiment, the first weight member 2008 has a hollow portion 2023
that forms the light side 2021 of the weight member 2008.
[0119] As shown in FIG. 33, the second weight member 2009 is also
preferably releasably coupled to the sole portion of the central
body member 2004 portion of the golf club head 2000 by a fastener
2025. The second weight member 2009 may generally have a material
density of greater than 13 g/cc, more preferably greater than about
15 g/cc, and most preferably greater than or equal to about 17
g/cc. The second weight member 2009 preferably has a light side
2026 and a heavy side 2027. The heavy side 2027 is preferably
substantially solid and as shown in FIGS. 29 and 31 is the side
identified with indicia such as with a dot. In a preferred
embodiment, the weight member 2009 has a hollow portion 2028 that
forms the light side 2026 of the second weight member 2009.
[0120] More preferably, at least one or both of the weight members
2008 or 2009 are comprised of a light side 2021 and 2026 that
includes a hollow portion 2023 and 2028 and a heavy side 2022 and
2027 that is substantially solid or is solid enough that the mass
on the heavy side is greater than the mass on the light side.
Alternatively, at least one or both of the weight members 2008 or
2009 are comprised of a light side 2021 and 2026 that includes a
hollow portion 2023 and 2028 that can be filled with a material
having a density of less than 4 g/cc and a heavy side 2022 and 2027
that is a hollow portion that is filled with a material having a
density of greater than about 7 g/cc and more preferably greater
than or equal to about 15 g/cc. As shown in FIGS. 29 and 31, the
weight member 2008 has less mass than weight member 2009 and is
preferably made from steel (or at least a material that has a lower
density that the density of weight member 2009). More preferably,
the first weight member 2008 has a mass of about 7 g and 14 g and
the second weight member has a mass of between about 15 g and 22 g.
Most preferably, the first weight member 2008 and the second weight
member 2009 can be interchanged in the front and aft locations as
shown in FIGS. 29 and 31 to move the CG-C by approximately 1 mm to
5 mm and most preferably by about 2.5 mm to 3.5 mm. In the most
preferred embodiment, the CG-C can be between about 14 mm and 21 mm
when the first weight member 2008 is in the aft location adjacent
the back edge 2005 and the CG-C can be between about 22 mm and 30
mm when the first weight member 2008 is in the forward position
adjacent the striking face 2001. Further, the first weight member
2008 and the second weight member 2009 preferably have
approximately the same difference in mass between the light sides
2021 and 2026 and the heavy sides 2022 and 2027. Preferably, the
difference in mass between the light sides 2021 and 2026 and the
heavy sides 2022 and 2027 is between about 4 g and 8 g. Thus, if
one of the weight members has the heavy side toward the heel in the
x-axis direction and the other has the heavy side toward the toe in
the x-axis direction, the CG of the golf club head 2000 can be
neutral in the x-axis direction as shown in FIG. 29. However, if
the weight members have both of their heavy sides 2022 and 2027
toward the toe or the heel in in the x-axis direction, the CG can
be moved away from the neutral position along the x-axis direction
toward the toe or heel, respectively. Preferably, the golf club
head CG can be moved at least 0.5 mm toward the toe or the heel
from the neutral location and more preferably, between about 0.7 mm
and 1.5 mm. As shown in FIG. 31, both the first weight member 2008
and the second weight member 2009 have the heavy sides 2022 and
2027 toward the toe in the x-axis direction such that the golf club
head CG is moved toward the toe by about 1 mm from the neutral
position GC-n. These weight members can both be rotated about the
fastener such that the CG is moved toward the heel by about 1 mm
from the neutral position CG-n and 2 mm from the far toe CG
position as shown in FIG. 31.
[0121] FIGS. 34 through 37 show different perspective and
cross-sectional views of golf club heads and their internal
components that are used to achieve the performance characteristics
described above. FIG. 34 shows a perspective view of an exemplary
design of a golf club head 3000 that capable of achieving the
performance characteristics previously discussed with respect to
the embodiments in FIGS. 1-3 and 13-15 in particular. The golf club
head 3000 is comprised of the essential components previously
discussed in FIGS. 1 and 13 in terms of a frontal portion having a
striking face 3001, a crown return 3002 and a sole return 3003 and
a rear portion 3004 comprised of an aft body. In order to achieve
the performance numbers above of a higher MOI-Y, a higher MOI-X,
and a lower MOI-Z, a significant amount of mass is allocated
towards the center of the golf club head away from the perimeter.
In order to achieve this, the present invention utilizes two
weighting members that are preferably comprised of high density
materials that have a higher density than the frontal portion 3001,
3002 and 3003 and the rear portion 3004. Preferably, as set forth
above, the frontal portion 3001, 3002 and 3003 can be formed of a
standard titanium material such as TI-6-4, Ti-8-1-1, beta-titanium,
and others that have a density of about 4 g/cc to 5 g/cc. The rear
portion 3004 is preferably formed of a standard composite fiber
composite laminate, chopped fiber composite generally referred to
as fiber-reinforced plastic (FRP), or a composite material such as
those disclosed in U.S. Publication No. 2015-0360094, which is
incorporated by reference in its entirety herein. Alternatively,
the rear portion 3004 is preferably formed of structural material
having a density of less than 3.0 g/cc such as a thermoplastic
materials such as those disclosed in U.S. application Ser. No.
16/528,210, filed on Jul. 31, 2019, which is incorporated by
reference in its entirety herein, polyetherimide (PEI), polyether
ether ketone (PEEK), polyphenylene sulfide (PPS), polysulfone
(PSU), polyacryletherketone (PEAK), polyetherketoneketone (PEKK)
and polyvinyl chloride (PVC). The rear portion 3004 is preferably
formed by compression molding, injection molding or 3D printing.
Additionally, the golf club head 3000 includes a sole plate member
3006 secured to an outer surface of the rear portion 3004. In a
preferred embodiment, the sole plate member 3006 is also formed
from standard titanium materials such as TI-6-4, Ti-8-1-1,
beta-titanium, and others that have a density of about 4 g/cc to 5
g/cc. In another preferred embodiment, the sole plate member 3006
is formed from stainless steel or similar material having a density
of about 7 g/cc to 8 g/cc.
[0122] The golf club head 3000 also includes weight members 3008
and 3009. In a first embodiment, the weight members 3008 and 3009
can have equal mass, for example between 10 and 15 grams each, such
that the CG of the club head 3000 is in a neutral position along
the z-axis direction. However, the weight members 3008 and 3009 can
also be comprised of a heavy weight, for example greater than 15
grams, and a light weight, for example less than 10 grams, such
that the CG can be moved forward or back along the z-axis direction
depending on the placement of the weights. With the heavy weight
located in the aft weight member 3009, the MOI-Y is increased and
is preferably greater than about 450 kg-mm.sup.2. Thus, in a
preferred golf club head 3000, the MOI-Y is greater than or equal
to approximately 2 times the MOI-Z. Conversely, when the heavy
weight is in the forward weight member 3008, the CG-C can be
significantly decreased. For example, a preferred golf club head
3000 can have a GC-C of between 14 mm to 21 mm.
[0123] Referring to FIG. 35, the golf club head 3000 further
includes an internal rib member 3010 that is located in the frontal
portion. The rib member 3010 is preferably located near or at the
overlapping juncture of the frontal portion and the rear portion
3004. Preferably, the depth DD of the golf club head from the
leading edge LE to the back edge 3005 is between 105 mm and 125 mm,
and more preferably between about 118 mm and 122 mm. The distance
of the crown return DCR from the leading edge to where the crown
return 3002 abuts the rear portion 3004 is preferably about 20 mm
and 35 mm and more preferably between about 30 mm and 34 mm. The
distance of the sole return DSR from the leading edge to where the
back end of the sole return 3003 is preferably about 24 mm and 44
mm and more preferably between about 35 mm and 42 mm. The rib
member 3010 is therefore preferably located a distance from the
leading edge that is between the DCR and the DSR or between 20 mm
and 44 mm. Most preferably, the rib member 3010 is angled such that
the distance from the leading edge to the crown portion of the rib
member 3010 (at the center of the crown in the heel-to-toe
direction, back from the face center) DRC is less than the distance
from the leading edge to the sole portion of the rib member 3010
(at the center of the sole in the heel-to-toe direction, back from
the face center) DRS. More preferably, DRC is preferably between 22
mm and 33 mm and DRS is between 26 mm and 42 mm and is at least 10%
greater than DRC. Thus, the rib member 3010 forms an angle
.alpha..sub.R that is between about 2.degree. and 10.degree. from
the vertical plane at the DRC to a point on the sole at the DRS.
The rib member 3010 has a rib height RH (the height of the rib
member from the inner surface of the frontal portion) that also
preferably varies from the crown center to the sole center and at
the heel and toe. Most preferably, the rib height RH is between
about 2 mm and 8 mm and is greatest at the sole center and shortest
at the heel and toe. Most preferably, the rib member 3010 has a rib
height RH of about 5 mm at the sole center, 4 mm at the crown
center and is 3 mm to 3.5 mm at the heel and toe.
[0124] The center of the first weight member 3008 is preferably
located a distance DW1 from the leading edge LE of about 15 mm to
25 mm. The center of the second weight member 3009 is preferably
located a distance DW2 from the leading edge LE of about 80 mm to
115 mm.
[0125] Referring to FIGS. 36 and 37, the second weight member 3009
is shown in a close-up cross-sectional view. The second weight
member 3009 is comprised of an internal weight member 3021 and an
external weight member 3022 with a fastener 3020 coupling the
members together to the rear portion 3004. The first weight member
3008 preferably has a similar construction but would secure about
the frontal portion on the sole return 3003. Most preferably, the
first weight member 3008 and the second weight member 3009 have
similar shaped external weight members 3022 that can be
interchanged. In this embodiment, the internal weight member 3021
and the external weight member also secure the sole plate member
3006 to the rear portion 3004 by having the rear portion 3004 and
the sole plate member 3006 compressed between the internal weight
member 3021 and the external weight member 3022. In the weight
embodiment shown in FIG. 37, the sole plate member 3006 and the
internal weight member 3021 are also threaded so that they can be
coupled to the rear portion 3004 before the external weight member
3022 is couple by the fastener 3020.
[0126] Referring to FIGS. 38-41, another embodiment of a rear
portion 4004 is shown with a pinch weight member 4009 secured near
the back edge 4005 that is used to achieve the performance
characteristics described above. The pinch weight member 4009 is
similar to the second weight member 3009 discussed above. The pinch
weight member 4009 is comprised of an internal weight member 4021
and an external weight member 4022 with a fastener 4020 coupling
the members together to compress the rear portion 4004. A first
weight member, not shown, preferably has a similar construction,
but would secure about a frontal portion, also not shown. In the
weight embodiment shown in FIG. 41, the sole portion 4012 is
compressed between the internal weight member 4021 and a weight
retaining pocket 4023 which are also threaded so that they can be
coupled to the rear portion 4004 before the external weight member
4022 is coupled to the weight retaining pocket 4023 by the fastener
4020. The exterior surface of the weight retaining pocket 4023 is
cylindrical with treads and the interior surface is preferably
hexagonal or other polygon and matches the shape of the exterior
weight member 4022 such that the exterior weight member 4022 cannot
rotate in the weight retaining pocket 4023.
[0127] In a preferred embodiment, the rear portion 4004 is formed
from a crown portion 4011 and a sole portion 4012 that can be
coupled by a joint connector 4013. The crown portion 4011 and the
sole portion 4012 are preferably injection molded separately and
then coupled by the joint connector 4013. The materials for the
crown portion 4011 and the sole portion 4012 are preferably the
same and the material for the joint connector is preferably the
same or is at least compatible such that it easily joins to the
crown portion 4011 and the sole portion 4012.
[0128] In a most preferred embodiment, the rear portion 4004 is
preferably formed from a high crystallinity PPS, that is a PPS in
which the crystallinity is greater than 40%, and more preferably,
greater than about 50% as measured using differential scanning
calorimetry (DSC) at a heating rate of 20.degree. C./min. In order
to increase the crystallinity level in PPS, it is recommended that
the material be injection molded into molds that are at a
temperature of greater than 115.degree. C. and more particularly in
a mold that is between about 125.degree. C. and 135.degree. C. In
the most preferred embodiment, the PPS crystallinity is between
about 50% and 70%. Preferably, the PPS can be formed without any
filler or can contain a filler such as glass filler. In the glass
filler PPS embodiment, the PPS preferably has greater than about
20% glass filler, more preferably between about 20% and 50% and
most preferably between about 30% and 50%. The material preferably
has a uniform thickness of about 0.5 mm to about 2 mm. However, in
one embodiment, the heel side 4007 has a thickness that is less
than the thickness of the toe side 4006. In another embodiment, the
thickness varies such that it is thinnest on the crown portion 4011
and thicker on the sole portion 4012. In this embodiment, the crown
portion 4011 has a thickness that is preferably between about 0.5
mm and 1 mm and the sole portion 4012 thickness is between about 1
mm and 2 mm.
[0129] In yet another embodiment of the present invention, with
reference to FIGS. 42-43, the golf club head and their internal
components that are used to achieve the performance characteristics
described above. FIG. 42 shows a front view of an exemplary design
of a golf club head 5000 that capable of achieving the performance
characteristics previously discussed with respect to the
embodiments in FIGS. 1-3 and 13-15 in particular. The golf club
head 5000 is comprised of the essential components previously
discussed in FIGS. 1 and 13 in terms of a frontal portion 5001
having a striking face, not shown, a crown return 5002 and a sole
return 5003 and a rear portion 5004 comprised of an aft body. In
order to achieve the performance numbers above of a higher MOI-Y, a
higher MOI-X, and a lower MOI-Z, a significant amount of mass is
allocated towards the center of the golf club head away from the
perimeter. In order to achieve this, the present invention can
utilize weighting members as discussed above that are preferably
comprised of high density materials that have a higher density than
the frontal portion 5001 and the rear portion 5004. Preferably, as
set forth above, the frontal portion 5001 can be formed of a
standard titanium material such as TI-6-4, Ti-8-1-1, beta-titanium,
and others that have a density of about 4 g/cc to 5 g/cc. The rear
portion 5004 is preferably formed from a multi-layer thermoplastic
composite construction as set forth in co-pending U.S. application
Ser. Nos. 17/205,678 and 17/225,862, which are incorporated by
reference herein in their entirety. Alternatively, the rear portion
5004 is preferably formed of structural material having a density
of less than 3.0 g/cc such as thermoplastic materials such as those
disclosed in U.S. application Ser. No. 16/528,210, filed on Jul.
31, 2019, which is incorporated by reference in its entirety
herein, polyetherimide (PEI), polyether ether ketone (PEEK),
polyphenylene sulfide (PPS), polysulfone (PSU),
polyacryletherketone (PEAK), polyetherketoneketone (PEKK) and
polyvinyl chloride (PVC).
[0130] In this embodiment, the golf club head 5000 can be comprised
of a plurality of support members 5014, 5015, and 5016 that extend
from the crown to the sole of the rear portion 5004 and from the
back edge 5005 toward the front edge 5006 of the rear portion 5004,
essentially perpendicular to the face. The support member 5015 is
in the center of the club head in the toe-to-heel direction,
parallel to the x-axis. The support member 5014 is on the toe side,
between 20% and 70% of the distance from the support member 5015
and the furthest edge on the toe side. The support member 5016 is
on the heel side, between 20% and 70% of the distance from the
support member 5015 and the furthest edge on the heel side.
Preferably, support members 5014 and 5016 are equidistance from the
support member 5015. The support members 5014, 5015 and 5016
preferably have a maximum height H parallel to the y-axis, a
maximum depth D parallel to the z-axis and a thickness t. The depth
D is preferably greater than the maximum height H and the thickness
t is preferably between about 0.5 mm and 1.5 mm. Preferably, the
support members 5014, 5015, and 5016 are comprised of a plurality
of angled strut members 5017 that form angles .alpha. in between
the struts of between 30 degrees and 100 degrees. Thus, in a first
embodiment, the support members are a lattice structure. In a more
preferred embodiment, the support members 5014, 5015, and 5016 are
also comprised of vertical strut members 5018 and 5019, extending
substantially parallel to the y-axis, at the rear and the front of
the rear portion 5004, respectively. The angled strut members 5017
preferably couple the vertical strut members 5018 and 5019.
[0131] The advantage of the support members 5014, 5015 and 5016 is
that they prevent the crown portion 5007 of the rear portion 5004
from deflecting relative to the sole portion 5008 of the rear
portion 5004 in the y-axis and also prevents the portions from
shearing with respect to each other in the z-axis. Preferably, the
support members 5014, 5015 and 5016 are formed from the same
material as the rear portion 5004 and can be thermal formed/welded
to the crown portion 5007 and the sole portion 5008 or coupled via
an adhesive.
[0132] Still further, it is preferable that the club heads
discussed above have a peak amplitude and Critical Time similar to
those discussed with reference to FIG. 11 in U.S. Pat. No.
10,245,479, which issued on Apr. 2, 2019, the entirety of which is
incorporated by reference herein.
[0133] In another embodiment of the present invention, the frontal
portion 5001 and the rear portion 5004 can be formed of a standard
titanium materials such as TI-6-4, Ti-8-1-1, beta-titanium, and
others that have a density of about 4 g/cc to 5 g/cc. The frontal
portion 5001 preferably comprises a cast crown return 5002 and sole
return 5003 and a stamped striking face. In this embodiment, the
support members 5014, 5015 and 5016 are again preferably formed
from the same material as the rear portion 5004. The preferred
method of forming the support members 5014, 5015 and 5016 comprises
forming a wax of the rear portion having a plurality of tabs on the
inner surface and preforming a plurality of wax support members.
The preformed wax support members can then be coupled to the wax
rear portion by "welding" the wax support members to the tabs on
the inner surface of the wax rear portion to form a final rear wax
for casting. Then, the rear portion 5004 can be cast such that the
support members 5014, 5015 and 5016 are integrally formed
therewith.
[0134] Other than in the operating example, or unless otherwise
expressly specified, all of the numerical ranges, amounts, values
and percentages such as those for amounts of materials, moment of
inertias, center of gravity locations, loft, draft angles, various
performance ratios, and others in the aforementioned portions of
the specification may be read as if prefaced by the word "about"
even though the term "about" may not expressly appear in the value,
amount, or range. Accordingly, unless indicated to the contrary,
the numerical parameters set forth in the above specification and
attached claims are approximations that may vary depending upon the
desired properties sought to be obtained by the present invention.
At the very least, and not as an attempt to limit the application
of the doctrine of equivalents to the scope of the claims, each
numerical parameter should at least be construed in light of the
number of reported significant digits and by applying ordinary
rounding techniques.
[0135] Notwithstanding that the numerical ranges and parameters
setting forth the broad scope of the invention are approximations,
the numerical values set forth in the specific examples are
reported as precisely as possible. Any numerical value, however,
inherently contains certain errors necessarily resulting from the
standard deviation found in their respective testing measurements.
Furthermore, when numerical ranges of varying scope are set forth
herein, it is contemplated that any combination of these values
inclusive of the recited values may be used.
[0136] It should be understood, of course, that the foregoing
relates to exemplary embodiments of the present invention and that
modifications may be made without departing from the spirit and
scope of the invention as set forth in the following claims.
* * * * *