U.S. patent application number 09/683311 was filed with the patent office on 2002-04-18 for face coating for a golf club head.
This patent application is currently assigned to Callaway Golf Company. Invention is credited to Byrne, Wayne H., Reyes, Herbert.
Application Number | 20020045491 09/683311 |
Document ID | / |
Family ID | 27504196 |
Filed Date | 2002-04-18 |
United States Patent
Application |
20020045491 |
Kind Code |
A1 |
Reyes, Herbert ; et
al. |
April 18, 2002 |
Face coating for a golf club head
Abstract
A composite golf club head having a club having a striking plate
portion with a texture coating is disclosed herein. The golf club
head has a crown component composed of a plurality of plies of
pre-preg material and a sole component composed of a plurality of
plies of pre-preg material. The texture coating is composed of a
plurality of polymer resin particles, a medium and a coupling
agent. The polymer resin particles are preferably composed of a
polyethylene or polypropylene material. The texture coating
provides added durability to the composite striking plate
portion.
Inventors: |
Reyes, Herbert; (Laguna
Niguel, CA) ; Byrne, Wayne H.; (Murrieta,
CA) |
Correspondence
Address: |
CALLAWAY GOLF C0MPANY
2285 RUTHERFORD ROAD
CARLSBAD
CA
92008
|
Assignee: |
Callaway Golf Company
Carlsbad
CA
|
Family ID: |
27504196 |
Appl. No.: |
09/683311 |
Filed: |
December 12, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09683311 |
Dec 12, 2001 |
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09947290 |
Sep 5, 2001 |
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09947290 |
Sep 5, 2001 |
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09877652 |
Jun 8, 2001 |
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09877652 |
Jun 8, 2001 |
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09474670 |
Dec 29, 1999 |
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09474670 |
Dec 29, 1999 |
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08958723 |
Oct 23, 1997 |
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Current U.S.
Class: |
473/345 ;
473/324; 473/349 |
Current CPC
Class: |
B29C 70/342 20130101;
A63B 53/0466 20130101; A63B 53/0433 20200801; Y10T 428/25 20150115;
A63B 2209/023 20130101; A63B 53/0462 20200801; A63B 53/0437
20200801; B29C 70/865 20130101; A63B 53/0458 20200801; A63B
2053/0491 20130101; A63B 53/0416 20200801; A63B 60/00 20151001;
A63B 53/0408 20200801; A63B 53/04 20130101; B29L 2031/5227
20130101 |
Class at
Publication: |
473/345 ;
473/324; 473/349 |
International
Class: |
A63B 053/04 |
Claims
We claim as our invention:
1. A composite golf club head comprising: a face component composed
of a plurality of pre-preg plies having fibers, the plurality of
pre-preg plies ranging from 20 to 70 plies, the face component
having a striking plate portion and a return portion, the striking
plate portion having a thickness in the range of 0.010 inch to
0.250 inch, and the return portion tapering in thickness rearward
from a perimeter of the striking plate portion; a crown composed of
a plurality of pre-preg plies ranging from 3 to 20 plies, the crown
attached to the face component; a sole composed of a plurality of
pre-preg plies ranging from 3 to 20 plies, the sole having a ribbon
portion and a bottom portion, the bottom portion of the sole
attached to the return portion of the face component and the ribbon
portion of the sole attached to the crown; a weighting member
disposed within the plies of pre-preg of the ribbon portion of the
sole; and a textured coating applied to the striking plate portion,
the texture coating comprised of a plurality of polymer resin
particles, a medium and a coupling agent, the plurality of polymer
resin particles present in an amount ranging from 5% to 30% of the
volume of the texture coating, the textured coating having a
thickness of 0.0005 inch to 0.003 inch.
2. The golf club head according to claim 1 wherein the textured
coating has a thickness in the range of 0.001 inch to 0.0015
inch.
3. The golf club head according to claim 1 wherein the plurality of
resin particles of the textured coating are composed of a
polyethylene material.
4. The golf club head according to claim 1 wherein the medium is a
clear coat.
5. The golf club head according to claim 1 wherein the medium is a
methylsiloxane with silica nanoparticles.
6. The golf club head according to claim 1 wherein the coupling
agent is a silane material.
7. A golf club comprising: a golf club head having a volume of 350
cubic centimeters to 400 cubic centimeters, the golf club head
composed of a plurality of plies of pre-preg, the golf club head
having a striking plate portion with a textured coating thereon,
the textured coating comprised of a plurality of polymer resin
particles, a medium and a coupling agent, the plurality of polymer
resin particles present in an amount ranging from 5% to 30% of the
volume of the texture coating, the textured coating having a
thickness of 0.0005 inch to 0.003 inch; a shaft having a tip end
and a butt end, the shaft composed of a graphite material and the
tip end of the shaft attached to the golf club head; and a grip
placed over a butt end of the shaft; wherein the golf club has a
mass less than 290 grams, and the golf club head has a coefficient
of restitution ranging from 0.80 to 0.93 under standard USGA
conditions.
8. A composite golf club head comprising: a face component composed
of a plurality of pre-preg plies ranging from 20 to 70 plies, the
face component having a striking plate portion and a return portion
extending laterally rearward from a perimeter of the striking
plate, the striking plate portion having a thickness in the range
of 0.010 inch to 0.250 inch; a crown composed of a plurality of
pre-preg plies ranging from 3 to 20 plies, the crown attached to
the face component and overlapping an upper section of the return
portion, the upper section of the return portion extending rearward
from the perimeter of the striking plate portion a distance of at
least 0.5 inch; a sole component composed of a plurality of
pre-preg plies ranging from 3 to 20 plies, the sole component
having a ribbon portion and a bottom portion, the bottom portion of
the sole component attached to a lower section of the return
portion of the face component and the ribbon portion of the sole
component attached to the crown component, the lower section of the
return portion extending rearward from the perimeter of the
striking plate portion a distance of at least 0.5 inch; a texture
coating on the striking plate portion, the texture coating
consisting of a plurality of polymer resin particles with diameters
ranging from 18 microns to 50 microns, a silane coupling agent and
a clear coat, wherein the plurality of resin particles ranges from
5% to 10% of the volume of the texture coating, the silane coupling
agent ranges 0.01% to 2% of the volume of the texture coating, and
the clear coat is at least 88% of the volume of the texture
coating.
9. A composite golf club head comprising: a body composed of a
plurality of pre-preg plies having fibers, the body having a sole,
a crown, a ribbon and a striking plate portion defining a hollow
interior, the striking plate portion having a thickness in the
range of 0.010 inch to 0.250 inch; and a textured coating applied
to the striking plate portion, the texture coating comprised of a
plurality of polymer resin particles, a medium and a coupling
agent, the plurality of polymer resin particles present in an
amount ranging from 5% to 30% of the volume of the texture coating,
the textured coating having a thickness of 0.0005 inch to 0.003
inch.
10. The golf club head according to claim 1 wherein the textured
coating has a thickness in the range of 0.001 inch to 0.0015 inch.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part application of
co-pending U.S. patent application Ser. No. 09/947,290, filed on
Sep. 5, 2001, which is a continuation-in-part application of
co-pending U.S. patent application Ser. No. 09/877,652, filed on
Jun. 8, 2001, which is a continuation of U.S. patent application
Ser. No. 09/474,670, filed on Dec. 29, 1999, now U.S. Pat. No.
6,248,025, which is continuation-in-part application of U.S. patent
application Ser. No. 08/958,723, filed on Oct. 23, 1997, now U.S.
Pat. No. 6,010,411.
FEDERAL RESEARCH STATEMENT
[0002] [Not Applicable]
BACKGROUND OF INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates to a face coating for a golf
club head. More specifically, the present invention relates to a
face coating for a golf club head composed of plies of pre-preg
material.
[0005] 2. Description of the Related Art
[0006] One of the first (if not the first) disclosures of a golf
club head composed of a plurality of plies of a pre-preg material
is Great Britain Patent Application Number 1201648 which was filed
in 1967 on behalf of William Charles Carlton. In 1984, U.S. Pat.
No. 4,449,707 issued to Hayashi et al., for a Golf Club Head Of
Carbon Fiber Reinforced Plastic, based on a Japanese Patent
Application originally filed in 1982. The Hayashi Patent discloses
surrounding a core with a fiber reinforced fabric to create a golf
club head with a proper center of gravity. Another disclosure is
U.S. Pat. No. 4,545,580 to Tomita et al., for a Wood-Type Golf Club
Head, based on a Japanese Patent Application originally filed in
1983. The Tomita Patent discloses a durable golf club head having
an outer shell composed of a fiber reinforced plastic material, a
foam center core, and an intermediate shell formed of a
thermoplastic resin material. Yet another disclosure is U.S. Pat.
No. 4,630,826 to Nishigaki et al., for Golf Club Head. The
Nishigaki Patent discloses body composed of a carbon resin layer
and a cast resin layer with a face insert block composed of a
ceramic material. Still another disclosure is U.S. Pat. No.
4,778,185 to Kurokawa, for Wood-Type Core-Shell Golf Club Heads,
based on a Japanese Patent Application originally filed in 1984.
The Kurokawa Patent discloses a golf club head composed of a foam
core and a shell composed of a material fiber reinforced plastic
having long and short fibers. Yet another disclosure is U.S. Pat.
No. 4,793,616 to Fernandez, for Golf Club. The Fernandez Patent
discloses a club head shell composed resin impregnated fibers and
ceramic particles within the resin to provide a high strength
shell. Yet another disclosure is U.S. Pat. No. 5,154,425 to
Niskanen et al., for a Composite Golf Club Head. The Niskanen
Patent discloses a club head composed of a metal matrix composite
of a ceramic matrix composite. Although the prior art has disclosed
many club head composed of composite materials, the prior art has
failed to provide a golf club head composed of a composite material
that addresses the durability of the face.
SUMMARY OF INVENTION
[0007] The present invention provides a golf club head that is
composed of a composite material and has a textured coating on its
striking plate for better durability.
[0008] One aspect of the present invention is a composite golf club
head having a body composed of a plurality of pre-preg plies having
fibers. The body has a sole, a crown, a ribbon and a striking plate
portion defining a hollow interior. The striking plate portion has
a thickness in the range of 0.010 inch to 0.250 inch. A textured
coating is applied to the striking plate portion. The texture
coating includes a plurality of polymer resin particles, a medium
and a coupling agent. The plurality of polymer resin particles are
present in an amount ranging from 5% to 30% of the volume of the
texture coating. The textured coating has a thickness of 0.0005
inch to 0.003 inch.
[0009] Having briefly described the present invention, the above
and further objects, features and advantages thereof will be
recognized by those skilled in the pertinent art from the following
detailed description of the invention when taken in conjunction
with the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0010] FIG. 1 is an exploded view of a golf club head of the
present invention.
[0011] FIG. 2 is a front view of a golf club head of the present
invention.
[0012] FIG. 3 is a top plan view of a golf club head of the present
invention.
[0013] FIG. 4 is a heel end view of a golf club head of the present
invention.
[0014] FIG. 5 is a toe end view of a golf club head of the present
invention.
[0015] FIG. 6 is a bottom plan view of a golf club head of the
present invention.
[0016] FIG. 7 is a cross-sectional view of the golf club head of
FIG. 3 along line 7-7.
[0017] FIG. 8 is a cross-sectional view of the golf club head of
FIG. 2 along line 8-8.
[0018] FIG. 9 is an isolated cross-section view of a face preform
of a golf club head of the present invention.
[0019] FIG. 9A is an enlarged view of area A of FIG. 9.
[0020] FIG. 9B is an enlarged view of area B of FIG. 9.
[0021] FIG. 10 is an isolated cross-section view of a crown/face
preform of a golf club head of the present invention.
[0022] FIG. 11 is an isolated cross-section view of a sole preform
of a golf club head of the present invention.
[0023] FIG. 12 is a top plan view of a golf club head of the
present invention illustrating the variation in thickness of the
walls of the golf club head.
[0024] FIG. 13 is a front plan view of a golf club head of the
present invention illustrating the variation in thickness of the
walls of the golf club head.
[0025] FIG. 14 is a bottom plan view of a golf club head of the
present invention illustrating the variation in thickness of the
walls of the golf club head.
[0026] FIG. 15 is a heel end view of a golf club head of the
present invention illustrating the variation in thickness of the
walls of the golf club head.
[0027] FIG. 16 is a plan view of a face/crown ply having a ninety
degree orientation.
[0028] FIG. 17 is a plan view of a full face ply having a ninety
degree orientation.
[0029] FIG. 18 is a plan view of a face doubler ply having a ninety
degree orientation.
[0030] FIG. 19 is a plan view of a sole ply having a negative
forty-five degree orientation.
[0031] FIG. 20A is a cross-sectional view of the striking plate
portion of the golf club head illustrating an embodiment of the
texture coating of the present invention, comprising resin
particles within a medium.
[0032] FIG. 20B is an alternative embodiment of FIG. 20A, showing
agglomerated resin particles within the medium of the present
invention.
[0033] FIG. 20C is yet another alternative embodiment of FIG. 20A,
showing agglomerated dissimilar size resin particles within the
medium of the present invention.
DETAILED DESCRIPTION
[0034] As shown in FIGS. 1-6, a golf club head of the present
invention is generally designated 20. The club head 20 is either a
fairway wood or a driver. The drivers range in loft angle of from
six degrees to fifteen degrees. The club head 20 has a body 22 that
is generally composed of a composite material such as plies of
carbon pre-preg sheets. The body 22 has a crown 24, a striking
plate 26, a sole 28 with a bottom portion 28a and a ribbon 30. The
ribbon preferably has an upper ribbon wall 30a and a lower ribbon
wall 30b. The ribbon 30 generally extends from a toe end 32 to a
heel end 34. The ribbon 30 generally begins at one end of the
striking plate 26 and ends at an opposite end of the striking plate
26. A rear 36 of the body 22 is opposite the striking plate 26 and
is defined by portions of the ribbon 30, the crown 24 and the sole
28. Also, at the heel end 34 of the club head 20 is an internal
tube 38 with an opening 39 for placement of a shaft therein. The
internal tube 38 is placed within the hollow interior 44 of the
body 22. Within the ribbon is a weight member 40.
[0035] A sole plate 42 is disposed within a recess 29 of the bottom
portion 28a of the sole 28. The sole plate 42 is preferably
composed of a metal material such as aluminum or titanium, and
preferably has a mass of 5 grams to 20 grams. A preferred mass for
an aluminum sole plate 42 is approximately 11 grams, and a
preferred mass for a titanium sole plate 42 is approximately 18
grams. The sole plate 42 is preferably bonded within the recess 29
through use of adhesives. The sole plate 42 preferably has embossed
graphics thereon. The sole plate 42 increases the durability of the
club head 20 since the sole 28 often impacts the ground during the
striking of a golf ball.
[0036] The club head 20 of the present invention also has a greater
volume than a composite club head of the prior art while
maintaining a weight that is substantially lower or equivalent to
that of the prior art. The volume of the club head 20 of the
present invention ranges from 175 cubic centimeters to 450 cubic
centimeters, more preferably ranges from 300 cubic centimeters to
400 cubic centimeters, and is most preferably 360 cubic centimeters
for a driver. The mass of the club head 20 of the present invention
ranges from 165 grams to 300 grams, preferably ranges from 175
grams to 225 grams, and most preferably from 188 grams to 195
grams. The body 22 of plies of pre-preg material has a mass ranging
from 80 grams to 120 grams, and most preferably 98 grams.
[0037] The volume of the present invention is increased by
increasing the vertical distance of the club head 20 from the sole
28 to the crown 24, as opposed to the horizontal distance of the
heel end 34 to the toe end 32. This increase in volume is brought
about by the dual wall structure of the ribbon 30. The upper ribbon
wall 30a is approximately perpendicular relative to the crown 24,
while the lower ribbon wall 30b preferably has angle between 25
degrees to 75 degrees relative to the crown 24. The greater volume
of the club head 20 allows the club head 20 to be more forgiving
than prior art golf club heads while providing better performance.
The mass of club head 20 is much lower than metal club heads of
similar volumes, and thus the large volume does not deter from the
swing of a golfer.
[0038] The striking plate 26 has a smaller aspect ratio than
striking plate plates of the prior art. The aspect ratio as used
herein is defined as the width, w, of the striking plate divided by
the height, h, of the striking plate 26, as shown in FIG. 2A. In
one embodiment, the width w is 90 millimeters and the height h is
54 millimeters giving an aspect ratio of 1.666. In conventional
golf club heads, the aspect ratio is usually much greater than 1.
For example, the original GREAT BIG BERTHA.RTM. driver had an
aspect ratio of 1.9. The aspect ratio of the present invention
preferably ranges from 1.0 to 1.7.
[0039] As shown in FIG. 7, the internal tube 38 lies within the
hollow interior 44 of the club head 20. The internal tube is
preferably composed of a metal material and has a mass ranging from
8 grams to 20 grams. The internal tube 38 is most preferably
composed of stainless steel and has a mass of approximately 14
grams. The internal tubing 38 has a bore 130 to receive an insert
and a shaft, not shown, therein. Such an insert is discussed in
co-pending U.S. patent application Ser. No. 09/652,491, filed on
Aug. 31, 2000, for a golf Club With Hosel Liner, which is hereby
incorporated by reference in its entirety. Preferably, the club
head 20 has a hollow interior 44 defined by the body 22, however,
the light weight of the composite body 22 allows for numerous
manipulations in placement of weight, foam, sound enhancing devices
and the like within the hollow interior 44.
[0040] Referring specifically to FIG. 1, the club head 20 has a
weight member 40 disposed within the plies of pre-preg that compose
the ribbon 30 of the club head 20. Preferably, the weight member 40
is composed of three weight members 40a, 40b and 40c. One such
weight member 40 is described in co-pending U.S. patent application
Ser. No. 09/474,688, filed on Dec. 29, 1999, and entitled A
Composite Golf Club Head With An Integral Weight Strip, which is
hereby incorporated by reference in its entirety. Another such
method is described in co-pending U.S. patent application Ser. No.
09/947,292, for Internal Weighting For A Composite Golf Club Head,
filed on Sep. 5, 2001, and hereby incorporated by reference in its
entirety. The weight member 40 has a mass ranging from 30 grams to
80 grams, more preferably 45 grams to 70 grams, and most preferably
54 grams. The weight member 40 is preferably composed of a metal
material integrated into a polymer medium. The metal material is
preferably selected from copper, tungsten, steel, aluminum, tin,
silver, gold, platinum, or the like. A preferred metal is tungsten.
The weight member 40 has a density greater than the composite
material of the body 22. Preferably, the weight member 40 extends
from approximately the heel end 34 of the striking plate 26 through
the rear 36 to the toe end 32 of the striking plate 26. However,
the weight member 40 may only extend along the rear 36 of the
ribbon 30, the heel end 34 of the ribbon 30, the toe end 32 of the
ribbon 30, or any combination thereof. Those skilled in the
pertinent art will recognize that other weighting materials may be
utilized without departing from the scope and spirit of the present
invention.
[0041] The placement of the weighting members 40a-c allows for the
moment of inertia of the golf club head 20 to be optimized. A more
thorough description of the optimization of the moments of inertia
is disclosed in co-pending U.S. patent application Ser. No.
09/796,951, filed on Feb. 27, 2001, entitled High Moment of Inertia
Composite Golf Club, and hereby incorporated by reference in its
entirety. In one preferred example of the golf club head 20 of the
present invention, the moment of inertia about the lxx axis through
the center of gravity is approximately 2566 2 grams-centimeters
squared (g-cm.sup.2), the moment of inertia about the lyy axis
through the center of gravity is approximately 1895 g-cm.sup.2, and
the moment of inertia about the Izz axis through the center of
gravity is approximately 3368 g-cm.sup.2.
[0042] As shown in FIGS. 8, 9, 9A and 9B, a return portion 100 is a
transition area from a perimeter 29 of the striking plate 26
rearward towards the crown 24. The return portion 100 has a
thickness ranging from 0.100 inch to 0.200 inch to control the
compliance of the striking plate 26. The return portion 100 has an
upper section 100a, a lower section 100b, a heel section 100c, not
shown, and a toe section 100d, not shown. The return portion 100
also has a taper region 101, which includes an upper tapering
region 101a, a lower tapering region 101b, a heel tapering region
101c, not shown, and a toe tapering region 101d, not shown. The
tapering region 101 tapers in thickness from a greater thickness
nearer the striking plate portion 26 to a lesser thickness rearward
toward the crown 24.
[0043] The return portion 100 has a predetermined length which
extends rearward from the perimeter 29 of the striking plate
portion 26 into the crown 24. Preferably, the distance of the
return portion 100, Dr, ranges from 0.25 inch to 2.0 inches, more
preferably from 0.5 inch to 1.75 inches, and most preferably 1.5
inches. Preferably, the distance from the perimeter 29 to the
beginning of the tapering region 101 of the return portion 100
ranges from 0.25 inch to 1.5 inches, and most preferably 1.0
inch.
[0044] The body 22 is manufactured from a face component 125, which
includes the striking plate portion 26 and the return portion 100,
a crown component 124 and a sole component 128. The crown component
124 overlaps the face component 125, as shown in FIG. 10. The sole
component 128 includes the ribbon portion 30 and the bottom portion
28a. The sole component 128 is attached to the crown component 124
and the face component 125.
[0045] FIGS. 16-19 illustrate preferred pre-preg sheets for forming
the composite body of the golf club head 20. FIG. 16 illustrates a
face/crown ply pre-preg sheet that is generally designated 55. The
face/crown ply 55 has a plurality of fibers 51 dispersed within a
resin body 53. The fibers 51 are preferably composed of a carbon
material. Alternatively, the fibers 51 may be aramid fibers, glass
fibers or the like. The resin is typically an epoxy material. The
relation of the fibers 51 to the striking plate 26, when the
striking plate 26 is in a position to strike a golf ball,
determines the orientation of the fibers 51. If the fibers 51 are
parallel with the ground, or in other words extending across from
the toe end to the heel end, then the face/crown ply 55 has a zero
degree orientation. If the fibers 51 are approximately
perpendicular to the ground, as shown in FIG. 16, or in other words
extending from the crown to the sole, then the face/crown ply 55
has a ninety degrees orientation.
[0046] FIG. 17 illustrates a full face ply pre-preg sheet that is
generally designated 57. As with the face/crown ply 55, the full
face ply 57 has a plurality of fibers 51 dispersed within a resin
body 53. The fibers 51 extend from the sole 28 to the crown 24, and
thus the full face ply 57 has fibers 51 that are perpendicular to
the ground when it is in a position for striking a golf ball.
Therefore, the full face ply 57 of FIG. 17 has a ninety degrees
orientation.
[0047] FIG. 18 illustrates a face doubler ply pre-preg sheet that
is generally designated 58. As with the face/crown ply 55, the face
doubler ply 58 has a plurality of fibers 51 dispersed within a
resin body 53. The fibers 51 extend from the sole 28 to the crown
24, and thus the face doubler ply 58 has fibers 51 that are
perpendicular to the ground when it is in a position for striking a
golf ball. Therefore, the face doubler ply 58 of FIG. 18 has a
ninety degrees orientation.
[0048] FIG. 19 illustrates a sole ply pre-preg sheet that is
generally designated 59. As with the face/crown ply 55, the sole
ply 59 has a plurality of fibers 51 dispersed within a resin body
53. The fibers 51 extend at a forty-five degree angle relative to
the ground when it is in a position for striking a golf ball.
Therefore, the sole ply 59 of FIG. 19 has a forty-five degree
orientation.
[0049] As previously stated, the preferred composite material is
plies of carbon pre-peg sheets. Plies of pre-preg composite sheets
are manufactured by pulling strands of fiber in a parallel motion,
preferably carbon, aramid or glass fiber, through a resin film and
allowing the resin to partially cure or `stage`. When the resin is
partially staged, the resin holds the fibers together such that the
fibers form a malleable sheet with all of the fibers in a specific
orientation relative to an edge of the sheet. Preferred
orientations are zero degrees, plus forty-five degrees, minus
forty-five degrees and ninety degrees. Exemplary carbon pre-preg
fiber sheets may be obtained from Newport Composites of Santa Ana,
Calif., Fiberite Inc. of Green Tex., or Hexcel Inc. of Pleasonton,
Calif.
[0050] The manipulation of the thickness of the various regions of
the body 22 allows the golf club head 22 to have superior
durability, forgiveness and performance as compared to prior art
composite golf club heads. As shown in FIGS. 12-15, the thickness
of the body 22 is focused on the striking plate portion 26. In a
most preferred example: the region designated A of the striking
plate portion 26 has a thickness of approximately 0.169 inch; the
region designated B, at the junction of the crown 24 and striking
plate 26 has a thickness of approximately 0.188 inch; the region
designated C of the bottom portion 28a of the sole 28 has a
thickness of approximately 0.221 inch; the region designated D of
the ribbon 30 and of the bottom portion 28a has a thickness of
approximately 0.202 inch; the region designated E of the crown 24,
the bottom portion 28a and the ribbon 30 has a thickness of
approximately 0.033 inch; and the region designated F of the crown
24 has a thickness of approximately 0.191 inch. The regions
designated Z1, Z2, Z3, Z4, Z5 and Z6 are tapering zones where the
thickness tapers rearward.
[0051] The golf club head 20 is preferably manufactured using a
bladder molding process. One such process is described in U.S. Pat.
No. 6,248,025, which is hereby incorporated by reference. However,
those skilled in the pertinent art will recognize that other
manufacturing methods may be utilized without departing from the
scope and spirit of the present invention.
[0052] The coefficient of restitution of the club head 20 of the
present invention under standard USGA test conditions with a given
ball ranges from 0.8 to 0.9, preferably ranges from 0.81 to 0.87
and is most preferably 0.82. The coefficient of restitution (also
referred to herein as COR) is determined by the following
equation:
e=v.sub.2v.sub.1U.sub.1U.sub.2
[0053] wherein U.sub.1 is the club head velocity prior to impact;
U.sub.2 is the golf ball velocity prior to impact which is zero;
v.sub.1 is the club head velocity just after separation of the golf
ball from the striking plate of the club head; v.sub.2 is the golf
ball velocity just after separation of the golf ball from the
striking plate of the club head; and e is the coefficient of
restitution between the golf ball and the club striking plate.
[0054] The values of e are limited between zero and 1.0 for systems
with no energy addition. The coefficient of restitution, e, for a
material such as a soft clay or putty would be near zero, while for
a perfectly elastic material, where no energy is lost as a result
of deformation, the value of e would be 1.0. The thickness of the
striking plate 26 and the orientation of the plies of pre-preg
determine the coefficient of restitution of the golf club head 20.
Additionally, the thickness of the return 100 of the golf club head
20 allows for a greater deflection in the striking plate 26 which
increases the coefficient of restitution of the golf club head 20.
The return 100 couples the striking plate 26 to the crown 24 which
reduces the loss of energy to the striking plate 26 during impact
with a golf ball. If the return 100 is too thick, the striking
plate 26 is isolated and rigid, thereby reducing the coefficient of
restitution. If the return 100 is too thin, failure of the striking
plate 26 may occur upon impact with a golf ball.
[0055] FIGS. 20A-C represent various embodiments of the texture
coating 200 of the striking plate 26. The texture coating 20
comprises a number of resin particles 300, a medium 320 and a
coupling agent (not shown). The resin particles 300 can be
thermosetting or thermoplastic resins, and in a preferred
embodiment selected from polyethylene, polypropylene, olefins,
fluoropolymers, polyamides and polyamines. In a preferred
embodiment, the resin particles 300 are composed of a thermoplastic
crystalline polyolefin, most preferably the polyolefin is a
polyethylene material or polypropylene material such as produced by
Shamrock Corporation. Preferably, the each of the plurality of
resin particles 300 have a specific gravity ranging from 0.90 grams
per cubic centimeter (g/cc) to 0.97 g/cc, and most preferably 0.93
g/cc. The plurality of resin particles 300 are dispersed in the
medium 320 preferably under high speed mixing.
[0056] Each of the plurality of resin particles 300 preferably have
a high viscosity which is useful for air drying or baking systems,
up to temperatures of 500.degree. F., without losing their particle
definition.
[0057] Although pictorially represented as spherical, the resin
particles 300 can be selected from several shapes with smooth
surfaces preferred to assist in uniform distribution throughout the
medium 320. Each of the resin particles 300 has a size of
preferably ranging from 10 microns to 240 microns, more preferably
from 10 to 30 microns, even more preferably from 15 microns to 25
microns, and most preferably 18 microns.
[0058] Any numbers of conventional methods can be used to apply the
texture coating 200, such as brushing, spraying, electrostatic
methods, powder coating and two component systems. A preferred
method is spraying the texture coating onto the striking plate 26
subsequent to all other finishing procedures. The golf club head 20
is covered, only exposing the striking plate 26. In a preferred
embodiment, the texture coating 200 is applied within line 26A, as
shown in FIG. 2A, and thus only the striking plate portion 26 is
coated with the texture coating 200. In a preferred embodiment, the
texture coating 200 is applied over the scorelines of the striking
plate portion 26.
[0059] The texture coating 200 is preferably applied uniformly to a
thickness of 0.0005 inch to 0.003 inch, more preferably 0.0009 inch
to 0.002 inch, and most preferably 0.001 inch to 0.0015 inch.
[0060] Characteristics of medium 320 include an ability to mix with
the resin particles 300 and bond to structural material of the
striking plate 26, followed by drying to a solid coating. Suitable
material choices for the medium 320 include aqueous or organic
solutions or suspensions, liquid adhesives, clear coats and paints.
In a preferred embodiment, the medium 320 comprises a two component
acrylic polyurethane clear coat capable of binding the resin
particles 300 and adhering to the surface of the striking plate 26.
Such a coating is sold by Magna, as acrylic urethane #490C0117. The
resin particles 300 form up to 20% by volume of the texture coating
200. In a most preferred embodiment, the resin particles 300 form
5% to 10% by volume of the texture coating 200. In an alternative
embodiment, the medium 320 is methylsiloxane with silica
nanoparticles such as PERMA NEW COATING from California Hardcoat. A
texture coating 200 utilizing this methylsiloxane has a thickness
ranging from 3 to 12 microns.
[0061] The coupling agent serves to alter the surface chemistry of
the resin particles 300 and the medium 320, thus promoting improved
bonding both within the texture coating 200, and to the surface of
the striking plate 26. Preferred embodiments of the coupling agent
include silanes and inorganic acids such as phosphoric acid, with a
most preferred embodiment being Silane 187A from Shell Chemical
Co.
[0062] The texture coating 200 preferably has a satin gloss,
however, alternatively the texture coating may have a matte gloss.
The texture coating 200 provides greater durability, better scratch
resistance and abrasion resistance for the striking plate 26
composed of a plurality of plies of pre-preg material. The texture
coating 200 also has reduced cracking.
[0063] From the foregoing it is believed that those skilled in the
pertinent art will recognize the meritorious advancement of this
invention and will readily understand that while the present
invention has been described in association with a preferred
embodiment thereof, and other embodiments illustrated in the
accompanying drawings, numerous changes, modifications and
substitutions of equivalents may be made therein without departing
from the spirit and scope of this invention which is intended to be
unlimited by the foregoing except as may appear in the following
appended claims. Therefore, the embodiments of the invention in
which an exclusive property or privilege is claimed are defined in
the following appended claims.
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