U.S. patent application number 15/060946 was filed with the patent office on 2016-06-30 for multi-zone golf club heads.
This patent application is currently assigned to Acushnet Company. The applicant listed for this patent is Acushnet Company. Invention is credited to Uday Deshmukh, Charles E. Golden.
Application Number | 20160184667 15/060946 |
Document ID | / |
Family ID | 50275030 |
Filed Date | 2016-06-30 |
United States Patent
Application |
20160184667 |
Kind Code |
A1 |
Deshmukh; Uday ; et
al. |
June 30, 2016 |
MULTI-ZONE GOLF CLUB HEADS
Abstract
A golf club head with low and high density zones designed to
provide specific densities for use in various parts of the club
head to achieve maximum volume and properties within specific
weight goals. The low and high density zones may be formed from
laminates having different equivalent densities than the layers
used to form the laminates.
Inventors: |
Deshmukh; Uday; (Carlsbad,
CA) ; Golden; Charles E.; (Encinitas, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Acushnet Company |
Fairhaven |
MA |
US |
|
|
Assignee: |
Acushnet Company
Fairhaven
MA
|
Family ID: |
50275030 |
Appl. No.: |
15/060946 |
Filed: |
March 4, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13615774 |
Sep 14, 2012 |
9278263 |
|
|
15060946 |
|
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Current U.S.
Class: |
473/345 |
Current CPC
Class: |
A63B 53/04 20130101;
A63B 53/0433 20200801; A63B 53/0425 20200801; A63B 2209/00
20130101; A63B 60/00 20151001; A63B 53/0429 20200801; A63B 53/0408
20200801; A63B 53/0466 20130101; A63B 53/0437 20200801; A63B
53/0412 20200801; A63B 2053/0491 20130101 |
International
Class: |
A63B 53/04 20060101
A63B053/04 |
Claims
1. A golf club head, comprising: a first zone comprising a body
defining an inner volume, sole, and a skirt, wherein the first zone
has a first density ranging from about 3 g/cm.sup.3 to about 4
g/cm.sup.3, and wherein the first zone is formed from a first
laminate, wherein the first laminate comprises a first layer and a
second layer, and wherein the second layer faces the inner volume;
a second zone comprising a crown, wherein the second zone is formed
from a second laminate having a second density ranging from about 3
g/cm.sup.3 to about 4 g/cm.sup.3, wherein the second laminate is
different from the first laminate; and a third zone comprising a
face, wherein the third zone comprises a third laminate comprising
three layers.
2. The golf club head of claim 1, wherein the second density is
different from the first density.
3. The golf club head of claim 1, wherein the first layer has a
density ranging from about 3 g/cm.sup.3 to about 4 g/cm.sup.3 and
the second layer has a density ranging from about 2 g/cm.sup.3 to
about 3 g/cm.sup.3.
4. The golf club head of claim 1, wherein the first layer has a
first thickness from about 0.1 mm to about 0.5 mm, and wherein the
second layer has a second thickness ranging from about 0.4 to about
0.8.
5. The golf club head of claim 1, wherein the first layer has a
first thickness, wherein the second layer has a second thickness,
and wherein the ratio of the first thickness to second thickness
ranges from about 1:1 to about 1:4.
6. The golf club head of claim 1, further comprising a weight.
7. The golf club head of claim 1, wherein the second laminate
comprises a third layer having a third density and a fourth layer
having a fourth density, wherein the fourth density is less than
the third density, and wherein the fourth layer faces the inner
volume.
8. The golf club head of claim 7, wherein the third layer has a
third thickness and the fourth layer has a fourth thickness, and
wherein the fourth thickness is greater than the third
thickness.
9.-16. (canceled)
17. A golf club head, comprising: a first zone comprising a body
defining an inner volume, sole, and a skirt, wherein the first zone
has a density ranging from about 3 g/cm.sup.3 to about 4
g/cm.sup.3, and wherein the first zone is formed from a first
laminate, wherein the first laminate comprises a first layer having
a first density and a second layer having a second density less
than the first density, and wherein the second layer faces the
inner volume; a second zone comprising a crown; and a third zone
comprising a face.
18. The golf club head of claim 17, wherein the first layer has a
density ranging from about 3 g/cm.sup.3 to about 4 g/cm.sup.3 and
the second layer has a density ranging from about 2 g/cm.sup.3 to
about 3 g/cm.sup.3.
19. The golf club head of claim 17, wherein the first layer has a
first thickness, wherein the second layer has a second thickness,
and wherein the ratio of the first thickness to second thickness
ranges from about 1:1 to about 1:4.
20. The golf club head of claim 17, wherein the first layer has a
first thickness from about 0.1 mm to about 0.5 mm, and wherein the
second layer has a second thickness ranging from about 0.4 to about
0.8.
21. The golf club head of claim 1, wherein the first laminate
comprises a cladding bond between the first and second layers.
22. The golf club head of claim 1, wherein the first layer
comprises titanium, titanium alloy, or combinations thereof and the
second layer comprises aluminum, aluminum alloy, or combinations
thereof.
23. The golf club head of claim 17, wherein the first laminate
comprises a cladding bond between the first and second layers.
24. The golf club head of claim 17, wherein the first layer
comprises titanium, titanium alloy, or combinations thereof and the
second layer comprises aluminum, aluminum alloy, or combinations
thereof.
25. A golf club head, comprising a body defining an inner volume, a
sole, a skirt, a crown, and a face, wherein the crown comprises a
first laminate, wherein the first laminate has a density ranging
from about 2.5 g/cm.sup.3 to about 4.5 g/cm.sup.3, wherein the
skirt and, optionally, the sole, comprises a second laminate,
wherein the second laminate has a density less than the density of
the first laminate and ranging from about 2.5 g/cm.sup.3 to about
4.5 g/cm.sup.3, and wherein the first laminate comprises a first
layer having a first density and a second layer having a second
density less than the first density, wherein the second layer faces
the inner volume, and wherein the first and second layers are
joined by a cladding bond.
26. The golf club head of claim 25, wherein the first layer
comprises titanium, titanium alloy, or combinations thereof and the
second layer comprises aluminum, aluminum alloy, or combinations
thereof.
27. The golf club head of claim 25, wherein the first laminate has
a density ranging from about 2.75 g/cm.sup.3 to about 4.0
g/cm.sup.3.
28. The golf club head of claim 27, wherein the second laminate
comprises a first layer having a first density and a second layer
having a second density less than the first density, wherein the
second layer faces the inner volume, and wherein the first and
second layers are joined by a cladding bond.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a golf club head comprising
zones designed to provide specific densities for use in various
parts of the club head to achieve maximum volume and properties
within specific weight goals. More specifically, the present
invention relates to a golf club head with properties that may be
manipulated based on zones in the club head that are formed from
laminates having different overall densities.
BACKGROUND OF THE INVENTION
[0002] Golf club designers are constantly manipulating the shape,
size, and materials used to manufacture clubs in an effort to
maximize performance. For example, fairway woods and hybrids
typically have a similar overall mass as a driver, but less than
half the volume of a driver. In particular, modern drivers are
approximately 460 cc, whereas modem fairway woods range from
approximately about 150 to 180 cc. Therefore, manufacturers
typically use stainless steel materials for fairway woods and
hybrids since the high density of steel provides a desirable mass
distribution for the smaller head size. However, the smaller size
of the face in fairway woods and hybrids makes it difficult to
achieve maximum coefficient of restitution when using stainless
steel because the elastic modulus is relatively high, and the face
must remain a certain thickness in order not to compromise the
durability.
[0003] While other lower density materials such as titanium or
aluminum-based materials may be used to make the fairway wood,
which increases the COR of the club head because of the lower
modulus of the material, the low density of the material
necessitates additional mass that must be added to meet the target
head weight. Indeed, to achieve desirable mass properties in
fairway woods, much of the discretionary mass is driven both toward
the perimeter and low on the sole with the use of weights hidden
within the club head. When made from titanium, the weights must be
large and incorporated on the sole to keep the center of gravity
(COG) as low as possible. However, the moment of inertia (MOI) (the
resistance to twisting of any golf club head when the golf ball is
impacted off center) may suffer with such a design and the large
concentrated mass in the center of the sole may lead to acoustic
issues. While other materials may be used for the weights, the
bonding of non-titanium weights to a titanium-based club head is
difficult to achieve with dissimilar metals. Alternatively,
manufacturers have attempted to use higher density materials such
as steel to form the sole of the otherwise titanium-based club
head. However, creating a robust metallurgical bond around the
perimeter of the steel plate is highly problematic.
[0004] Other types of clubs have similar issues. In fact, as
drivers have increased in volume, their MOIs have also increased
providing "larger sweet spots" and more forgiveness on off-center
hits. However, when the volume is maximized through spatially
distributing the mass in all three orthogonal orientations, the COG
is positioned substantially rearward from the front face of the
golf club head and high, which renders shots struck off-center from
the sweet spot of the golf club head undesirable as a result of the
increase in backspin. And, when weight members are attached to
manipulate the COG, the club may become heavy and unwieldy,
possibly to the point of limiting a golfer's swing speed and
adversely affecting the golfer's swing mechanics. Similarly,
efforts to manipulate the distribution of material in a club head
with low and high density materials in various portions of the club
head may impact the COR of the club head depending on how the
material is distributed in the club head.
[0005] It would be advantageous to a provide materials for golf
clubs that maximize the internal mass distribution and volume of
the club head depending on the shape, size, and performance
requirements of the particular club head. In addition, it would be
beneficial to minimize the elasticity on the face to increase COR
while still using a face material that has high strength since the
face is a high stress area. Furthermore, there is a need in the art
for materials that are capable of being joined to each other via
conventional or unconventional methods. The present invention
provides materials, golf club heads including the materials, and
methods of making the golf club heads that includes the materials
to achieve the proper balance between mass distribution and club
head performance.
SUMMARY OF THE INVENTION
[0006] The present invention relates to a golf club head,
including: a first zone including a body defining an inner volume,
sole, and a skirt, wherein the first zone has a first density
ranging from about 3 g/cm.sup.3 to about 4 g/cm.sup.3, and wherein
the first zone is formed from a first laminate, wherein the first
laminate includes a first layer and a second layer, and wherein the
second layer faces the inner volume; a second zone including a
crown, wherein the second zone is formed from a second laminate
having a second density ranging from about 3 g/cm.sup.3 to about 4
g/cm.sup.3, wherein the second laminate is different from the first
laminate; and a third zone including a face, wherein the third zone
includes a third laminate including three layers.
[0007] In one embodiment, the second density is different from the
first density. In another embodiment, the first layer has a density
ranging from about 3 g/cm.sup.3 to about 4 g/cm.sup.3 and the
second layer has a density ranging from about 2 g/cm.sup.3 to about
3 g/cm.sup.3. In still another embodiment, the first layer has a
first thickness from about 0.1 mm to about 0.5 mm, and wherein the
second layer has a second thickness ranging from about 0.4 to about
0.8. In yet another embodiment, the first layer has a first
thickness, wherein the second layer has a second thickness, and
wherein the ratio of the first thickness to second thickness ranges
from about 1:1 to about 1:4.
[0008] The second laminate may include a third layer having a third
density and a fourth layer having a fourth density, wherein the
fourth density is less than the third density, and wherein the
fourth layer faces the inner volume. In one embodiment, the third
layer has a third thickness and the fourth layer has a fourth
thickness, and wherein the fourth thickness is greater than the
third thickness.
[0009] The golf club head may include one or more weights and one
or more corresponding weight ports.
[0010] The present invention also relates to a golf club head that
includes a body defining an inner volume, a sole, a skirt, a crown,
and a face, wherein the sole includes a first zone, wherein the
first zone has a first density ranging from about 5.5 g/cm.sup.3 to
about 7 g/cm.sup.3, wherein the crown includes a second zone,
wherein the second zone has a second density less than the first
density and ranging from about 3 g/cm.sup.3 to about 4.5
g/cm.sup.3, and wherein the face includes a third zone.
[0011] In one embodiment, the first zone includes a first laminate
including a first layer including titanium, titanium alloy, or a
combination thereof and a second layer having a density ranging
from about 6.0 g/cm.sup.3 to about 8.0 g/cm.sup.3. In an alternate
embodiment, the first zone includes monolithic zirconium. The
second layer may include steel, steel alloy, or a combination
thereof. In this aspect of the invention, the third zone may
include a laminate including a plurality of layers, and wherein the
laminate has a density less than the first density. In another
embodiment, the third zone includes monolithic titanium.
[0012] The second zone may include a second laminate including a
third layer and a fourth layer, wherein the third layer has a third
density and includes titanium, titanium alloy, or a combination
thereof, and wherein the fourth layer has a fourth density less
than the third density and includes aluminum, aluminum alloy, or
combinations thereof.
[0013] The present invention is also directed to a golf club head
that includes: a first zone including a body defining an inner
volume, sole, and a skirt, wherein the first zone has a density
ranging from about 3 g/cm.sup.3 to about 4 g/cm.sup.3, and wherein
the first zone is formed from a first laminate, wherein the first
laminate includes a first layer having a first density and a second
layer having a second density less than the first density, and
wherein the second layer faces the inner volume; a second zone
including a crown; and a third zone including a face.
[0014] The first layer may have a density ranging from about 3
g/cm.sup.3 to about 4 g/cm.sup.3 and the second layer has a density
ranging from about 2 g/cm.sup.3 to about 3 g/cm.sup.3. The first
layer may also have a first thickness, wherein the second layer has
a second thickness, and wherein the ratio of the first thickness to
second thickness ranges from about 1:1 to about 1:4. In one
embodiment, the first layer has a first thickness from about 0.1 mm
to about 0.5 mm, and wherein the second layer has a second
thickness ranging from about 0.4 to about 0.8.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Further features and advantages of the invention can be
ascertained from the following detailed description that is
provided in connection with the drawings described below:
[0016] FIG. 1 shows a cross-section of one embodiment of a golf
club head according to the present invention;
[0017] FIGS. 2A and 2B shows a side of a component of a golf club
head according to one embodiment of the present invention; and
[0018] FIG. 3 shows an exploded view of a golf club head according
to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] The present invention relates to wood-type golf club heads,
golf clubs, and the like (such as drivers, fairway woods, hybrids,
and/or the like), as well as to methods of making and using such
clubs and club heads. The club head body member may take on a
variety of different forms, shapes, and/or sizes without departing
from this invention and includes, but is not limited to, a club
head body member defining an interior chamber, a striking face, a
crown portion, and a sole portion.
[0020] The club head may be made of a one piece construction or
from a multi-piece construction. In a multi-piece construction, the
club head body member is made from multiple components having one
or more zones that are joined together via welding, brazing,
adhesive bonding, or combinations thereof. In one embodiment, a
club head body member includes a plurality of zones, each formed
with materials or laminates having different densities that are
joined together. The club head body member may include two zones,
three zones, four zones, five zones, six zones, or more than six
zones.
[0021] While the overall weight of the wood-type golf club head of
the invention will vary depending on the specific type, i.e.,
driver, fairway wood, hybrid, the use of the materials described
herein and the methods of forming the golf club heads of the
invention provide a manufacturer the ability to maximize volume,
increase COR, adjust MOI and COG by strategically distributing the
mass in different zones of the club head, and improve overall
durability of the club head. For example, even through a wood-type
golf club head will always be designed to weigh between about 190 g
and 205 g, the specific materials used in the golf club head allow
the maximum volume, COR, and strength with adjustability in the MOI
and COG for the particular type of wood-type golf club head.
High Density Zones
[0022] In certain areas of the club head, high density materials
are optimal because they spread out mass over a wider area as
opposed to a large mass at a localized point. For example, the sole
of the golf club head, which suffers repeated impact with the
ground, is a portion of the club head that requires durable
materials and provides design opportunities to keep the COG as low
or as close to the neutral axis as possible. The high density zones
of a club head of the present invention preferably have equivalent
densities ranging from about 5.5 g/cm.sup.3 to about 8 g/cm.sup.3.
In another embodiment, a high density zone according to the present
invention has an equivalent density ranging from about 5.75
g/cm.sup.3 to about 7.9 g/cm.sup.3. In yet another embodiment, the
equivalent density ranges from about 6 g/cm.sup.3 to about 7.8
g/cm.sup.3. In still another embodiment, the high density zones
have equivalent densities ranging from about 6 g/cm.sup.3 to about
7 g/cm.sup.3.
[0023] The thickness of the high density zones may vary depending
on the placement of the zone in the club head. In one embodiment,
the high density zone may have an average thickness that ranges
from about 0.5 mm to about 2.5 mm. In another embodiment, the
average thickness of the high density zone may range from about
0.75 mm to about 2.0 mm. In still another embodiment, the high
density zones have thicknesses ranging from about 1.0 mm to about
1.8 mm.
[0024] The weight of the high density zone may be from about 30 g
to about 50 g. In one embodiment, the mass of the high density zone
ranges from about 30 g to about 40 g. In another embodiment, the
mass of the high density zone ranges from about 34 g to about 38
g.
[0025] The high density zone or zones may comprise about 5 percent
to about 40 percent of the club head. In one embodiment, the high
density zone comprises about 10 percent to about 30 percent of the
club head. In another embodiment, the high density zone comprises
at least about 15 percent of the club head. In still another
embodiment, about 15 percent to about 20 percent of the club head
comprises one or more high density zones.
[0026] In one embodiment, the high density zone may be formed from
a laminate that includes at least two layers. The high density zone
may also be formed from more than two layers. For example, in one
embodiment, the high density zone includes at least three layers.
In another embodiment, the high density zone includes at least four
layers. In an alternate embodiment, the high density zone is formed
from a single layer.
[0027] For example, a high density zone according to the invention
may be formed from a first layer having a first density and a first
thickness and a second layer having a second density and a second
thickness. In this aspect of the invention, the first density may
range from about 6.0 g/cm.sup.3 to about 8 g/cm.sup.3. In another
embodiment, the first density ranges from about 6.5 g/cm.sup.3 to
about 7.9 g/cm.sup.3. In yet another embodiment, the first density
ranges from about 6.75 g/cm.sup.3 to about 7.8 g/cm.sup.3. In still
another embodiment, the first density ranges from about 7.0
g/cm.sup.3 to about 7.8 g/cm.sup.3. The second density may range
from about 3.5 g/cm.sup.3 to about 5.5 g/cm.sup.3. In another
embodiment, the second density ranges from about 4.0 g/cm.sup.3 to
about 5.0 g/cm.sup.3. In yet another embodiment, the second density
ranges from about 4.25 g/cm.sup.3 to about 4.75 g/cm.sup.3. In
still another embodiment, the second density ranges from about 4.3
g/cm.sup.3 to about 4.5 g/cm.sup.3.
[0028] The ratio of the first thickness to the second thickness may
be from about 0.5 to about 4. In one embodiment, the ratio of the
first thickness to the second thickness is about 1 to about 3. In
another embodiment, the ratio of the first thickness to the second
thickness is about 1 to about 2. The first thickness may range from
about 0.5 mm to about 1.0 mm. In one embodiment, the first
thickness ranges from about 0.55 mm to about 0.95 mm. In another
embodiment, the first thickness ranges from about 0.6 mm to about
0.9 mm. The second thickness may ranges from about 0.1 mm to about
0.8 mm. In one embodiment, the second thickness ranges from about
0.2 mm to about 0.7 mm. In another embodiment, the second thickness
ranges from about 0.3 mm to about 0.65 mm.
[0029] The first and second layers may be made from any material
having a density in the desired range. In one embodiment, the first
layer is formed from steel, zirconium, copper, nickel, zinc,
chromium, manganese, niobium, molybdenum, hafnium, tantalum, or
combinations and alloys thereof. The second layer may be formed
from titanium, titanium alloy, aluminum, aluminum alloy, or
combinations thereof. For example, a high density zone according to
the present invention may be formed from a first layer of stainless
steel and a second layer of titanium or titanium alloy.
[0030] Suitable, but not limiting examples of titanium materials
for use with the present invention include alpha or near-alpha
titanium alloys such as Ti-8Al-1V-1Mo, Ti-5Al-1Fe-1Cr-0.7Mo,
alpha-beta alloys such as Ti-6Al-4V (Ti-6-4), Ti-4.5Al-3V-2Fe-2Mo
(SP-700), and Ti-5Al-1Sn-1Zr-1V-0.8Mo (Ti-5111), and heat treated
beta alloys such as Ti-15-3-3-3, Beta C, DAT 51, DAT 55. Other
suitable titanium alloys include alpha and near-alpha alloys such
as Ti-0.3Mo-0.8Ni, Ti-3Al-2.5V, Ti-3Al-2.5V--Pd, Ti-3Al-2.5V--Ru,
Ti-5Al-2.5Sn, Ti-5Al-2.5Sn ELI, Ti-8Al-1Mo-1V, and
Ti-6Al-2Sn-4Zr-2Mo-0.1Si, alpha-beta alloys such as Ti-6Al-4V ELI,
Ti-6Al-4V-0.1Ru, Ti-6Al-7Nb, Ti-6Al-6V-2Sn, Ti-6Al-2Sn-4Zr-6Mo,
Ti-4Al-4Mo-2Sn-0.5Si, Ti-6Al-2Sn-2Zr-2Mo-2Cr-0.15Si, and
Ti-5Al-4Cr-4Mo-2Sn-2Zr, Ti-4Al-2.5V-1.5Fe, Ti-4.5Al-2Mo-1.5V-0.5Fe,
Ti-6Al-1.5V-1.5Mo-0.3Fe, Ti-5Al-4V-0.8Mo-0.5Fe, beta and near-beta
alloys such as Ti-10V-2Fe-3Al, Ti-3Al-8V-6Cr-4Zr-4Mo, and
Ti-3Al-8V-6Cr-4Zr-4Mo-0.05Pd, Ti-15Mo-5Zr-3Al, Ti-15Mo-3Al,
Ti-20V-3.5Al-1Sn, and Ti-5Al-5Mo-5V-3Cr, and mixtures thereof.
[0031] In one embodiment, the high density zone may form at least a
part of the sole of the golf club head. For example, as shown in
FIG. 1 the sole wall 20 may be formed from a high density zone. In
another embodiment, at least one other part of the club head is
formed form a high density zone.
[0032] When the high density zones are laminate, the laminates may
be formed using any conventional process available to those of
ordinary skill in the art. For example, the laminate may be formed
with the cladding or cold roll bonding process to the desired
thickness by rolling together a sheet of a first material and a
sheet of the second material under high pressure to form a
metallurgical bond between the two materials.
[0033] The laminate sheet may then be used to obtain the required
shapes via stamping, water jet cutting, or laser cutting. Once the
shapes for the high density zones are obtained, they may be warm or
hot formed to fabricate the components, which will ultimately be
joined together with other components to form the club head via
welding, brazing, adhesive bonding, ultrasonic energy, or
combinations thereof.
[0034] Because the melting point of the material used to form the
second layer may be less than the melting point of the material
used to form the first layer, welding the components together to
form the club head may lead to meltdown of the material used to
form the second layer. Accordingly, the second layer having a lower
melting point may be machined off along the perimeter of the shape
prior to component fabrication. Alternatively, other forms of
welding that generate less heat, i.e., laser welding or plasma
welding, may avoid material meltdown in the second laminate
layer.
[0035] The club head is preferably formed such that the less dense
layer of the laminate forms the outer layer of the club head and
the denser layer forms the inner surface. For example, in one
embodiment, the laminate is formed from titanium and steel and the
steel forms the inner surface of the high density zone.
Low Density Zones
[0036] Similar to the need for high density zones, golf club heads
also may include low density zones with mass savings spread out
over a broad area. For example, the crown of the golf club head
suffers minimal impact with the ground or ball and, thus, is an
area of the club head that may be formed from low density materials
in an effort to manipulate the overall weight of the club head and
the center of gravity of the club head.
[0037] The low density zones of a club head of the present
invention preferably have equivalent densities ranging from about
2.5 g/cm.sup.3 to about 4.5 g/cm.sup.3. In another embodiment, a
low density zone according to the present invention has an
equivalent density ranging from about 2.75 g/cm.sup.3 to about 4.0
g/cm.sup.3. In yet another embodiment, the equivalent density
ranges from about 3 g/cm.sup.3 to about 3.75 g/cm.sup.3. In still
another embodiment, the low density zones have equivalent densities
ranging from about 3 g/cm.sup.3 to about 3.70 g/cm.sup.3.
[0038] The thickness of the low density zones may vary depending on
the placement of the zone in the club head. In one embodiment, the
low density zone may have an average thickness that ranges from
about 0.1 mm to about 1.0 mm. In another embodiment, the average
thickness of the low density zone may range from about 0.2 mm to
about 0.8 mm. In still another embodiment, the low density zones
have thicknesses ranging from about 0.3 mm to about 0.75 mm.
[0039] The weight of the low density zone may be from about 10 g to
about 30 g. In one embodiment, the mass of the low density zone
ranges from about 15 g to about 25 g. In another embodiment, the
low density zone ranges in weight from about 18 g to about 22 g. In
this aspect of the invention, the low density zone preferably has a
weight range that is about 80 percent to about 98 percent of the
weight range of a Ti-6-4 crown having the same dimensions. In one
embodiment, the low density zone weight range is about 83 to about
97 percent of the weight range of a Ti-6-4 crown having the same
dimensions.
[0040] The low density zone or zones may comprise about 20 percent
to about 50 percent of the club head. In one embodiment, the low
density zone comprises about 25 percent to about 45 percent of the
club head. In another embodiment, the low density zone comprises at
least about 30 percent of the club head. In still another
embodiment, about 32 percent to about 40 percent of the club head
comprises one or more low density zones.
[0041] In one embodiment, the low density zone may be formed from a
laminate that includes at least two layers. The low density zone
may also be formed from more than two layers. For example, in one
embodiment, the low density zone includes at least three layers. In
another embodiment, the low density zone includes at least four
layers. In an alternate embodiment, the low density zone is formed
from a single layer.
[0042] For example, a low density zone according to the invention
may be formed from a first layer having a first density and a first
thickness and a second layer having a second density and a second
thickness. In this aspect of the invention, the first density may
range from about 3.5 g/cm.sup.3 to about 5.5 g/cm.sup.3. In another
embodiment, the first density ranges from about 4.0 g/cm.sup.3 to
about 5.0 g/cm.sup.3. In yet another embodiment, the first density
ranges from about 4.25 g/cm.sup.3 to about 4.75 g/cm.sup.3. In
still another embodiment, the first density ranges from about 4.3
g/cm.sup.3 to about 4.6 g/cm.sup.3. The second density may range
from about 1.5 g/cm.sup.3 to about 4.0 g/cm.sup.3. In another
embodiment, the second density ranges from about 2.0 g/cm.sup.3 to
about 3.5 g/cm.sup.3. In yet another embodiment, the second density
ranges from about 2.2 g/cm.sup.3 to about 3.0 g/cm.sup.3. In still
another embodiment, the second density ranges from about 2.3
g/cm.sup.3 to about 2.8 g/cm.sup.3.
[0043] The ratio of the first thickness to the second thickness may
be from about 6:1. In one embodiment, the ratio of the first
thickness to the second thickness is about 1:5. In another
embodiment, the ratio of the first thickness to the second
thickness is about 1:4. In still another embodiment, the ratio of
the first thickness to the second thickness is about 1:3. For
example, the first thickness to second thickness ratio may be from
about 1:2. In another embodiment, the low density zone has a first
thickness to second thickness ratio from about 1:1. The first
thickness may range from about 0.05 mm to about 0.5 mm. In one
embodiment, the first thickness ranges from about 0.1 mm to about
0.6 mm. In another embodiment, the first thickness ranges from
about 0.2 mm to about 0.3 mm. The second thickness may range from
about 0.2 mm to about 1.0 mm. In one embodiment, the second
thickness ranges from about 0.25 mm to about 0.7 mm. In another
embodiment, the second thickness ranges from about 0.30 mm to about
0.6 mm.
[0044] In one embodiment, the low density zone may form at least a
part of the crown of the golf club head. For example, as shown in
FIG. 1 the crown 30 may be formed from a low density zone.
[0045] In another embodiment, at least one other part of the club
head is formed form a second low density zone. For example, as
shown in FIG. 1, the second low density zone may form the skirt 40
and, optionally, at least a portion of the sole 20 of the club
head. In this aspect of the invention, the second low density zone
may have an equivalent density ranging from about 2.5 g/cm.sup.3 to
about 4.5 g/cm.sup.3. In another embodiment, the second low density
zone according to the present invention has an equivalent density
ranging from about 2.75 g/cm.sup.3 to about 4.0 g/cm.sup.3. In yet
another embodiment, the equivalent density of the second low
density zone ranges from about 3 g/cm.sup.3 to about 3.9
g/cm.sup.3. In still another embodiment, the second low density
zone has an equivalent density ranging from about 3.1 g/cm.sup.3 to
about 3.8 g/cm.sup.3.
[0046] The thickness of the second low density zone may vary
depending on the placement of the zone in the club head. In one
embodiment, the second low density zone may have an average
thickness that ranges from about 0.3 mm to about 1.5 mm. In another
embodiment, the average thickness of the low density zone may range
from about 0.4 mm to about 1.3 mm. In still another embodiment, the
low density zones have thicknesses ranging from about 0.5 mm to
about 1.0 mm.
[0047] The weight of the second low density zone may be from about
30 g to about 60 g. In one embodiment, the second low density zone
ranges in weight from about 35 g to about 50 g. In another
embodiment, the second low density zone ranges from about 38 g to
about 48 g. In this aspect of the invention, the second low density
zone preferably has a weight range that is about 80 percent to
about 98 percent of the weight range of a Ti-6-4 skirt/sole having
the same dimensions. In one embodiment, the second low density zone
weight range is about 83 to about 97 percent of the weight range of
a Ti-6-4 skirt/sole having the same dimensions.
[0048] The second low density zone or zones may comprise about 40
percent to about 60 percent of the club head. In one embodiment,
the second low density zone comprises about 45 percent to about 55
percent of the club head. In another embodiment, the second low
density zone comprises at least about 45 percent of the club head.
In still another embodiment, about 45 percent to about 53 percent
of the club head comprises one or more second low density
zones.
[0049] In one embodiment, the second low density zone may be formed
from a laminate that includes at least two layers. The second low
density zone may also be formed from more than two layers. For
example, in one embodiment, the second low density zone includes at
least three layers. In another embodiment, the second low density
zone includes at least four layers. In an alternate embodiment, the
second low density zone is formed from a single layer.
[0050] For example, a second low density zone according to the
invention may be formed from a first layer having a first density
and a first thickness and a second layer having a second density
and a second thickness. In this aspect of the invention, the first
density may range from about 3.5 g/cm.sup.3 to about 5.5
g/cm.sup.3. In another embodiment, the first density ranges from
about 4.0 g/cm.sup.3 to about 5.0 g/cm.sup.3. In yet another
embodiment, the first density ranges from about 4.25 g/cm.sup.3 to
about 4.75 g/cm.sup.3. In still another embodiment, the first
density ranges from about 4.3 g/cm.sup.3 to about 4.6 g/cm.sup.3.
The second density may range from about 1.5 g/cm.sup.3 to about 4.0
g/cm.sup.3. In another embodiment, the second density ranges from
about 2.0 g/cm.sup.3 to about 3.5 g/cm.sup.3. In yet another
embodiment second the first density ranges from about 2.2
g/cm.sup.3 to about 3.0 g/cm.sup.3. In still another embodiment,
the second density ranges from about 2.3 g/cm.sup.3 to about 2.8
g/cm.sup.3.
[0051] The ratio of the first thickness to the second thickness may
be from about 1:6. In one embodiment, the ratio of the first
thickness to the second thickness is about 1:5. In another
embodiment, the ratio of the first thickness to the second
thickness is about 1:4. In still another embodiment, the ratio of
the first thickness to the second thickness is about 1:3. For
example, the first thickness to second thickness ratio may be from
about 1:2. In another embodiment, the low density zone has a first
thickness to second thickness ratio from about 1:1. The first
thickness may range from about 0.1 mm to about 0.6 mm. In one
embodiment, the first thickness ranges from about 0.15 mm to about
0.5 mm. In another embodiment, the first thickness ranges from
about 0.16 mm to about 0.48 mm. The second thickness may range from
about 0.3 mm to about 1.0 mm. In one embodiment, the second
thickness ranges from about 0.35 mm to about 0.9 mm. In another
embodiment, the second thickness ranges from about 0.40 mm to about
0.8 mm.
[0052] The first and second layers in the low density zones may be
made from any material having a density in the desired range. In
one embodiment, the second layer is formed from aluminum, aluminum
alloy, or combinations thereof. The first layer may be formed from
titanium, titanium alloy, or combinations thereof. For example, a
second low density zone according to the present invention may be
formed from a first layer of titanium or titanium alloy and a
second layer of aluminum or aluminum alloy.
[0053] Suitable, but not limiting examples of titanium materials
for use with the low density zones of the present invention include
alpha or near-alpha titanium alloys such as Ti-8Al-1V-1Mo,
Ti-5Al-1Fe-1Cr-0.7Mo, alpha-beta alloys such as Ti-6Al-4V (Ti-6-4),
Ti-4.5Al-3V-2Fe-2Mo (SP-700), and Ti-5Al-1Sn-1Zr-1V-0.8Mo
(Ti-5111), and heat treated beta alloys such as Ti-15-3-3-3, Beta
C, DAT 51, DAT 55. Other suitable titanium alloys include alpha and
near-alpha alloys such as Ti-0.3Mo-0.8Ni, Ti-3Al-2.5V,
Ti-3Al-2.5V--Pd, Ti-3Al-2.5V--Ru, Ti-5Al-2.5Sn, Ti-5Al-2.5Sn ELI,
Ti-8Al-1Mo-1V, and Ti-6Al-2Sn-4Zr-2Mo-0.1Si, alpha-beta alloys such
as Ti-6Al-4V ELI, Ti-6Al-4V-0.1Ru, Ti-6Al-7Nb, Ti-6Al-6V-2Sn,
Ti-6Al-2Sn-4Zr-6Mo, Ti-4Al-4Mo-2Sn-0.5Si,
Ti-6Al-2Sn-2Zr-2Mo-2Cr-0.15Si, and Ti-5Al-4Cr-4Mo-2Sn-2Zr, beta and
near-beta alloys such as Ti-10V-2Fe-3Al, Ti-3Al-8V-6Cr-4Zr-4Mo, and
Ti-3Al-8V-6Cr-4Zr-4Mo-0.05Pd, Ti-15Mo-5Zr-3Al, Ti-15Mo-3Al,
Ti-20V-3.5Al-1Sn, and Ti-5Al-5Mo-5V-3Cr, and mixtures thereof.
[0054] Suitable, but not limiting examples of aluminum materials
for use with the low density zone include 1000 series, 2000 series,
3000 series, 4000 series, 5000 series, 6000 series, 7000 series and
8000 series aluminum alloys, examples of which are Al 2014, Al
2024, Al 3003, Al 5052, Al 5083, Al 6061, Al 6063, Al 7005, Al
7075, Al 8091, and combinations thereof.
[0055] When the low density zones are laminate, the laminates may
be formed using any conventional process available to those of
ordinary skill in the art. For example, the laminate may be formed
with the cladding or cold roll bonding process to the desired
thickness. In one embodiment, forming the laminate includes rolling
together a sheet of a first material and a sheet of the second
material under high pressure to form a metallurgical bond between
the two materials.
[0056] The laminate sheet may then be used to obtain the required
shapes via stamping, water jet cutting, or laser cutting. Once the
shapes for the low density zones are obtained, they may be warm or
hot formed to fabricate the components, which will ultimately be
joined together with other components to form the club head via
welding, brazing, adhesive bonding, ultrasonic energy, or
combinations thereof.
[0057] Because the melting point of the material used to form the
second layer may be less than the melting point of the material
used to form the first layer, welding the components together to
form the club head may lead to meltdown of the material used to
form the second layer. Accordingly, the second layer having the
lower melting point may be machined off along the perimeter of the
shape prior to component fabrication. Alternatively, other forms of
welding that generate less heat, i.e., laser welding or plasma
welding, may avoid material meltdown in the second laminate
layer.
[0058] The club head is preferably formed such that the denser
laminate layer of the low density zone forms the outer surface of
the club head and the less dense layer forms the inner surface. For
example, in one embodiment, the laminate is formed from titanium
and aluminum and the aluminum forms the inner surface of the high
density zone.
Reinforced Low Density Zones
[0059] Certain areas of the club head may be formed from a
reinforced low density zone. For example, in one embodiment, a
reinforced low density zone may be formed form a laminate that
includes a low density laminate and a reinforcing layer. As shown
in FIG. 2A, the reinforced low density zone 51 may include a low
density laminate 52 as discussed above with respect to the low
density zones with a reinforcing layer 56. In particular, the low
density laminate may have an equivalent density ranging from about
2.5 g/cm.sup.3 to about 4.5 g/cm.sup.3. In another embodiment, a
low density laminate according to the present invention has an
equivalent density ranging from about 2.75 g/cm.sup.3 to about 4.0
g/cm.sup.3. In yet another embodiment, the equivalent density of
the low density laminate ranges from about 3 g/cm.sup.3 to about
3.75 g/cm.sup.3. In still another embodiment, the low density
laminate has an equivalent density ranging from about 3 g/cm.sup.3
to about 3.70 g/cm.sup.3.
[0060] The low density laminate may be formed from a first layer 53
having a first density and a second layer 54 having a second
density. In one embodiment, the first density is greater than the
second density. For example, the first density may range from about
3.5 g/cm.sup.3 to about 5.5 g/cm.sup.3 and the second density may
range from about 1.5 g/cm.sup.3 to about 4.0 g/cm.sup.3. In another
embodiment, the first density ranges from about 4.0 g/cm.sup.3 to
about 5.0 g/cm.sup.3 and the second density ranges from about 2.0
g/cm.sup.3 to about 3.5 g/cm.sup.3. In yet another embodiment, the
first density ranges from about 4.25 g/cm.sup.3 to about 4.75
g/cm.sup.3 and the second density ranges from about 2.2 g/cm.sup.3
to about 3.0 g/cm.sup.3. In still another embodiment, the first
density ranges from about 4.3 g/cm.sup.3 to about 4.6 g/cm.sup.3
and the second density ranges from about 2.3 g/cm.sup.3 to about
2.8 g/cm.sup.3. The material used to form the first layer may be
any of the titanium materials discussed above with respect to the
low density zone. Likewise, in one embodiment, the material used to
form the second layer of the low density laminate may be any of the
aluminum materials discussed above with respect to the low density
zone.
[0061] The reinforcing layer 56 may be formed of a material having
a density of about 4 g/cm.sup.3 to about 5 g/cm.sup.3. In one
embodiment, the reinforcing layer 56 is formed from a material
having a density of about 4.2 g/cm.sup.3 to about 4.8 g/cm.sup.3.
In another embodiment, the material used to form the reinforcing
layer has a density of about 4.4 g/cm.sup.3 to about 4.6
g/cm.sup.3. The material used to form the reinforcing layer may be
titanium or titanium alloy.
[0062] The reinforced low density zone may be fabricated using a
number of methods. For example, the laminate may be formed with the
cladding or cold roll bonding process to the desired thickness by
rolling together a sheet of a first material and a sheet of the
second material under high pressure to form a metallurgical bond
between the two materials. The resulting laminate sheet may then be
used to obtain the required shapes via stamping, water jet cutting,
or laser cutting. Once the shapes for the low density zones are
obtained, the second layer may be machined to facilitate welding of
the reinforcing layer. In particular, as shown in FIG. 2A, the
second layer 54 may be machined off along the perimeter of the
laminate to create a step. The reinforcing layer 56 may be stamped
and machined to form a cavity to accommodate the second layer 54.
In the alternative, the reinforcing layer 56 may include multiple
components such as side walls 57a and 57b and base 58 that are
joined together. In one embodiment, the side walls and base are
formed of the same material. In another embodiment, the side walls
and base are formed of different materials.
[0063] As further shown in FIG. 2B, the low density laminate 52 and
reinforcing layer 56 may be welded together (for example with weld
material 60 along the perimeter) and machined to remove excess
material. The welding may be conventional welding, laser welding,
plasma welding, or variations thereof. The low density laminate 52
and reinforcing layer 56 may also be joined together via brazing,
adhesive bonding, ultrasonic energy, or combinations thereof.
[0064] After the reinforced low density zone is obtained, it may be
formed to provide a bulge and roll if used as a face insert and
welded to the face insert cavity. Alternatively, the low density
laminate 52 and reinforcing layer 56 may be welded into the face
cavity simultaneously.
Club Heads Formed From Low and High Density Zones
[0065] The club heads of the invention may include at least one
high density zone, at least one low density zone, at least one
reinforced low density zone, and combinations thereof. In one
embodiment, the club head includes a high density zone that forms
at least a portion of the sole. In another embodiment, the club
head includes a low density zone that forms at least a portion of
the crown. In yet another embodiment, a second low density zone
forms at least a portion of the club head body, skirt, and
sole.
[0066] In this aspect of the invention, the face may be formed from
monolithic titanium. In another embodiment, the face and the area
surrounding the face (leading crown and leading sole areas), may be
formed from monolithic titanium. In still another embodiment, the
club head may include a reinforced low density zone that forms at
least a portion of the face.
[0067] FIG. 3 shows a portion of a golf club head 100 according to
one embodiment of the present invention. In the illustrated
embodiment, the club head body member 110 may be formed from a
first low density titanium alloy. The crown 110 is formed form a
first low density zone. The face insert 130 is formed from a
reinforced low density zone. The club head body 120, which includes
the skirt and sole for the purposes of this embodiment, may be
formed from a second low density zone.
[0068] In another embodiment, at least a portion of the club head
body 120, is formed from a the second low density zone and at least
a second portion of the club head body 120, which includes the sole
124 may be formed from a high density zone. In particular, the
skirt 122 may be formed of a second low density zone and the sole
124 may be formed of a high density zone.
[0069] In such embodiments, the components may be coupled to each
other in a variety of manners with ultrasonic energy being one
preferred manner. In FIG. 1, the hosel is shown, but is not
considered to be part of the club head body member. At least one
weight port 126 may be used in the club head body. Furthermore,
while wood-type club heads are illustrated, the inventive
embodiments described herein are not intended to be limited to such
club heads. For example, iron-type club heads may also be designed
with high and low density zones. In particular, in one embodiment,
a high density zone may be incorporated into at least a portion of
the sole of an iron-type club head by using ultrasonic welding.
[0070] The high and low density zones may be joined together with
the club head body member (in the respective cavities) via welding,
infrared brazing, adhesive bonding, ultrasonic energy, or
combinations thereof. The zones may be joined together using the
same or different methods. As would be appreciated by those of
ordinary skill in the art, the type of welding used to join the
components together may be any suitable welding that results in a
joined product with the least weld material at the joints and heat
affected zones. In this aspect, suitable types of welding for use
with the present invention include, but are not limited to, laser
welding, plasma welding, TIG welding, MIG welding, or combinations
thereof. In one embodiment, the type of welding used to join either
or both of the crown and face components may be laser welding,
plasma welding, or combinations thereof. Without being bound to any
specific theory, laser and plasma welding reduces the amount of
material added at the joint and result in smaller heat affected
zones (as compared to TIG welding).
[0071] In another embodiment, at least two zones are joined with
ultrasonic energy. In particular, the use of ultrasonic energy may
be used to fabricate a club head with precise joints for maximum
performance. In addition, because ultrasonic processes do not use
or generate more than a minimum amount of heat, the steps discussed
above with respect to machining the second layer to avoid meltdown
may be avoided when using ultrasonic energy. Finally, because
ultrasonic energy does not result in oxidation or color change,
club heads and the components therein that are bonded with
ultrasonic energy will require less finishing (e.g., grinding and
polishing).
[0072] The golf club constructions described above may be employed
in a wood-type golf club. For a metal wood such as a driver or a
fairway wood, the club head has a volume of about 90 cc to about
460 cc. Preferably, the volume of a metal wood club head is at
least about 250 cc. According to one aspect of the invention, the
volume for a hybrid club is between about 100 cc and about 200 cc.
In one embodiment, the volume for a hybrid club is between about
125 cc and 150 cc. In one embodiment, the volume of a hybrid club
according to the present invention may be less than 130 cc.
[0073] Finishing touches, e.g., painting and sanding, may
optionally be performed for aesthetic purposes.
EXAMPLES
[0074] The following examples are provided to illustrate the
present invention, and should not be construed as limiting
thereof.
Example 1
A High Density Zone
[0075] A high density zone may be formed with the zone material and
properties set forth in Table 1 below.
TABLE-US-00001 TABLE 1 HIGH DENSITY ZONE Equivalent Average
Laminate Sole Total Sole Laminate Zone Density Sole Weight
Thickness Density Thickness Thickness Material (g/cm.sup.2) Area
(cm.sup.2) (g) Ratio (g/cm.sup.2) (mm) (cm) steel 7.80 46.00 35.88
n/a 7.80 1.00 0.10 Ti 6-4 4.43 46.00 35.88 n/a 4.43 1.80 0.18
zirconium 6.40 46.00 35.88 n/a 6.40 1.20 0.12 steel/Ti 7.8/4.43
46.00 35.88 1 6.09 1.24 .064/.064 steel/Ti 7.8/4.43 46.00 35.88 2
6.67 1.17 .078/.039 steel/Ti 7.8/4.43 46.00 35.88 3 6.96 1.12
.084/.028
[0076] When used in a sole of the club head with the area and
thickness dimensions as set forth above, the steel/titanium
laminate provides comparable center of gravity and moment of
inertia values as the monolithic zirconium and steel materials.
Example 2
Low Density Zone
[0077] A low density zone may be formed as set forth in Table 2
below.
TABLE-US-00002 TABLE 2 LOW DENSITY ZONE Average Laminate Total
Laminate Zone Density Thickness Thickness Thickness Material
(g/cm.sup.3) Area (cm.sup.2) Weight (g) Ratio (mm) (mm) Ti-6-4 n/a
103.1 22.83 n/a 0.5 n/a Laminate 1 3.07 103.1 19.00 1:5 0.6 0.1/0.5
Laminate 2 3.21 103.1 19.84 1:3 0.6 0.15/0.45 Laminate 3 3.34 103.1
20.68 1:2 0.6 0.2/0.4 Laminate 4 3.62 103.1 22.36 1:1 0.6
0.3/0.3
[0078] If the zone materials of Table 2 are used in a crown, the
weight savings using the laminates of the invention range from
about 2 percent to about 17 percent as compared to a crown formed
from Ti-6-4 (Table 3).
TABLE-US-00003 TABLE 3 LOW DENSITY ZONE WEIGHT SAVINGS Zone
Material Weight Savings (%) Laminate 1 16.8 Laminate 2 13.1
Laminate 3 9.4 Laminate 4 2.1
Example 3
Low Density Zone
[0079] A low density zone may be formed as set forth in Table 4
below.
TABLE-US-00004 TABLE 4 LOW DENSITY ZONE Average Laminate Total
Laminate Zone Density Thickness Thickness Thickness Material
(g/cm.sup.3) Area (cm.sup.2) Weight (g) Ratio (mm) (mm) Ti-6-4 n/a
139.6 22.83 n/a 0.75 n/a Laminate 5 3.13 139.6 39.28 1:4 0.9
0.18/0.72 Laminate 6 3.21 139.6 40.30 1:3 0.9 0.225/0.675 Laminate
7 3.34 139.6 42.01 1:2 0.9 0.3/0.6 Laminate 8 3.62 139.6 45.42 1:1
0.9 0.45/0.45
[0080] If the zone materials of Table 2 are used in the body, sole,
and skirt with an overall area as provided in Table 4, the weight
savings using the laminates of the invention range from about 2
percent to about 16 percent as compared to a crown formed from
Ti-6-4 (Table 5).
TABLE-US-00005 TABLE 5 LOW DENSITY ZONE WEIGHT SAVINGS Zone
Material Weight Savings (%) Laminate 1 15.3 Laminate 2 13.1
Laminate 3 9.4 Laminate 4 2.1
[0081] Although the present invention has been described with
reference to particular embodiments, it will be understood to those
skilled in the art that the invention is capable of a variety of
alternative embodiments within the spirit of the appended claims.
For example, golf club heads in accordance with examples of this
invention may include still additional features, if desired,
including features that are known and used in the art. For example,
a golf club head according to the invention may include a weighting
system that is permanently mounted to the club head body member,
e.g., on an interior or exterior of the club head body, extending
from the exterior to the interior of the club head body (e.g.,
through a weight port), etc., or, in the alternative, a weighting
system that includes weight member(s) that are movably and/or
removably mounted with respect to the club head body member using
structures and techniques that are known and used in the art (e.g.,
by screw or other mechanical connector attachments, by sliding
attachments, etc.). Alternately, the sole may include one or more
cavities that are capable of accommodating inserts having variable
weights. In addition, golf clubs according to the invention may
include one or more of: (a) a shaft member engaged with the club
head body; (b) a grip member engaged with the shaft, and/or (c) a
handle member engaged with the club head and/or the shaft. These
additional elements of the golf club structure may be included in
the overall club structure in any desired manner without departing
from this invention, including in conventional manners that are
known and used in the art (e.g., the shaft may be engaged with the
club head body member via an external hosel member, via an internal
hosel member, through an opening provided in the club head, via
adhesives, and/or via mechanical connectors.
* * * * *