U.S. patent application number 14/714108 was filed with the patent office on 2016-03-10 for golf club head.
This patent application is currently assigned to Acushnet Company. The applicant listed for this patent is Acushnet Company. Invention is credited to Stephanie Bezilla, Darryl C. Galvan, Charles E. Golden.
Application Number | 20160067561 14/714108 |
Document ID | / |
Family ID | 55436555 |
Filed Date | 2016-03-10 |
United States Patent
Application |
20160067561 |
Kind Code |
A1 |
Golden; Charles E. ; et
al. |
March 10, 2016 |
GOLF CLUB HEAD
Abstract
A golf club head including a striking face, a posterior body
portion including a crown portion and a sole portion, wherein the
striking face includes a heel side and a toe side, a geometric face
center, an impact area centered about the geometric face center and
stretching a distance K towards the toe side from the geometric
face center, and a distance K towards the heel side from the
geometric face center, a toe area including the remainder of the
striking on the toe side of the impact area, a heel area including
the remainder of the striking face on the heel side of the impact
area, wherein a maximum characteristic time of the striking face
occurs outside of the impact area.
Inventors: |
Golden; Charles E.;
(Encinitas, CA) ; Galvan; Darryl C.; (El Cajon,
CA) ; Bezilla; Stephanie; (Carlsbad, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Acushnet Company |
Fairhaven |
MA |
US |
|
|
Assignee: |
Acushnet Company
Fairhaven
MA
|
Family ID: |
55436555 |
Appl. No.: |
14/714108 |
Filed: |
May 15, 2015 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
14479002 |
Sep 5, 2014 |
|
|
|
14714108 |
|
|
|
|
Current U.S.
Class: |
473/342 |
Current CPC
Class: |
A63B 53/0437 20200801;
A63B 60/00 20151001; A63B 53/0466 20130101; A63B 53/0433 20200801;
A63B 53/0462 20200801; A63B 53/0458 20200801 |
International
Class: |
A63B 53/04 20060101
A63B053/04 |
Claims
1. A golf club head comprising: a striking face; a posterior body
portion comprising a crown portion and a sole portion, wherein said
crown portion is coupled to an upper portion of said striking face
and said sole portion is coupled to a lower portion of said
striking face; wherein said striking face comprises: a heel side
and a toe side; a geometric face center; an impact area centered
about said geometric face center and stretching a distance K
towards said toe side from said geometric face center, and a
distance K towards said heel side from said geometric face center;
a toe area comprising the remainder of said striking on said toe
side of said impact area; a heel area comprising the remainder of
said striking face on said heel side of said impact area; a major
axis located on said striking face and oriented substantially from
said heel side towards said toe side, wherein said major axis is
the longest line that can be drawn on said striking face, said
major axis having a length M; wherein said distance K is determined
by dividing said length M of said major axis by 4.85; wherein a
maximum characteristic time of said striking face occurs outside of
said impact area.
2. The golf club head of claim 1, wherein a maximum characteristic
time of said impact area is less than or equal to 257
microseconds.
3. The golf club head of claim 1, wherein a maximum characteristic
time of said toe area is less than or equal to 275
microseconds.
4. The golf club head of claim 1, wherein a maximum characteristic
time of said heel area is less than or equal to 275
microseconds.
5. The golf club head of claim 1, wherein a maximum characteristic
time of said toe area is greater than or equal to 257
microseconds.
6. The golf club head of claim 1, wherein a maximum characteristic
time of said heel area is greater than or equal to 257
microseconds.
7. A golf club head comprising: a striking face; a posterior body
portion comprising a crown portion and a sole portion, wherein said
crown portion is coupled to an upper portion of said striking face
and said sole portion is coupled to a lower portion of said
striking face; wherein said striking face comprises: a heel side
and a toe side; a geometric face center; an impact area centered
about said geometric face center and stretching a distance K
towards said toe side from said geometric face center, and a
distance K towards said heel side from said geometric face center;
a toe area comprising the remainder of said striking on said toe
side of said impact area; a heel area comprising the remainder of
said striking face on said heel side of said impact area; a major
axis located on said striking face and oriented substantially from
said heel side towards said toe side, wherein said major axis is
the longest line that can be drawn on said striking face, said
major axis having a length M; wherein said distance K is determined
by dividing said length M of said major axis by 4.85; wherein said
sole portion comprises a flexure spaced from said striking face,
said flexure comprising a front wall, an apex, and a rear wall,
wherein said front wall and said rear wall both extend into an
interior of said golf club head, and wherein said front wall and
said rear wall are coupled at said apex; wherein a maximum
characteristic time of said striking face occurs outside of said
impact area.
8. The golf club head of claim 7, wherein wherein said flexure
comprises a toe portion toeward of a geometric center of said
striking face and a heel portion heelward of said geometric center;
wherein either said toe portion of said flexure or said heel
portion of said flexure is more compliant than the opposite
portion; wherein a maximum characteristic time of said striking
face occurs in said toe area if said toe portion of said flexure is
more compliant than said heel portion of said flexure; wherein a
maximum characteristic time of said striking face occurs in said
heel area if said heel portion of said flexure is more compliant
than said toe portion of said flexure.
9. The golf club head of claim 8, wherein a maximum characteristic
time of said striking face occurs in said toe area.
10. A golf club head comprising: a striking face; a posterior body
portion comprising a crown portion and a sole portion, wherein said
crown portion is coupled to an upper portion of said striking face
and said sole portion is coupled to a lower portion of said
striking face; wherein said striking face comprises: a heel side
and a toe side; a geometric face center; an impact area centered
about said geometric face center and stretching a distance K
towards said toe side from said geometric face center, and a
distance K towards said heel side from said geometric face center;
a toe area comprising the remainder of said striking on said toe
side of said impact area; a heel area comprising the remainder of
said striking face on said heel side of said impact area; a major
axis located on said striking face and oriented substantially from
said heel side towards said toe side, wherein said major axis is
the longest line that can be drawn on said striking face, said
major axis having a length M; wherein said distance K is determined
by dividing said length M of said major axis by 4.85; a compliant
feature, said compliant feature asymmetrically effecting the
compliance of said striking face about said geometric face center;
wherein a maximum characteristic time of said toe area is greater
than said maximum characteristic time of said heel area.
11. The golf club head of claim 10, wherein said compliant feature
comprises a flexure spaced from said striking face, said flexure
comprising a front wall, an apex, and a rear wall, wherein said
front wall and said rear wall both extend into an interior of said
golf club head, and wherein said front wall and said rear wall are
coupled at said apex; wherein said flexure comprises a toe portion
toeward of a geometric center of said striking face.
12. The golf club head of claim 11, wherein said golf club head
further comprises a skirt portion at the intersection of said sole
portion and said crown portion and said flexure is formed in at
least a portion of said sole portion and in at least a portion of
said skirt portion.
13. The golf club head of claim 10, wherein said compliant feature
comprises a variable face thickness profile comprising a thick
central portion surrounded by a transition portion, said transition
portion surrounded by a thin perimeter portion, and wherein the
maximum thickness of said thick central portion, T.sub.thick is at
least three times the minimum thickness of said thin perimeter
portion, T.sub.thin.
14. The golf club head of claim 10, wherein said compliant feature
comprises a central face support element located centrally along a
width of said striking face.
15. The golf club head of claim 14, wherein said central face
support element spans at least a portion of the cavity formed at
the interface of said crown portion and said striking face.
16. The golf club head of claim 14, wherein said central face
support element spans at least a portion of the cavity formed at
the interface of said sole portion and said striking face.
17. The golf club head of claim 10, wherein said compliant feature
comprises a plurality of central face support elements located
centrally along a width of said striking face, a first of said
plurality of support elements spanning at least a portion of the
cavity formed at the interface of said crown portion and said
striking face, and a second of said plurality of support elements
spanning at least a portion of the cavity formed at the interface
of said sole portion and said striking face.
18. The golf club head of claim 10, wherein a maximum
characteristic time of said toe area is greater than or equal to
239 microseconds.
19. The golf club head of claim 10, wherein a maximum
characteristic time of said toe area is greater than or equal to
257 microseconds.
20. The golf club head of claim 10, wherein said compliance feature
comprises an adjustable weight capable of manipulating the location
of the center of gravity of said golf club head.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation-in-part of U.S.
patent application Ser. No. 14/479,002, to Golden et al., Golf Club
Head, filed on Sep. 5, 2014, currently pending, the disclosure of
which is hereby incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] This present technology generally relates to golf clubs, and
more specifically to golf club heads having improved compliance
over the striking face.
DESCRIPTION OF THE RELATED TECHNOLOGY
[0003] In the competitive industry of golf club design, distance
and accuracy are two of the most important performance factors that
help define the desirability of a metal wood type golf club.
Although some may argue that the look, feel, and sound of a golf
club may influence their opinion of a golf club; there is no
arguing that the performance factors play a major role in
determining the desirability of a golf club. The performance
factors of maximizing distance while maintaining accuracy becomes
even more prevalent in a metal wood type golf club head. Unlike
iron type golf club heads where accuracy of a golf shot clearly
trumps the distance benefits gained by any individual golf club,
metal wood type golf club heads are designed to allow a golfer to
hit the golf ball as far as possible and as straight as
possible.
[0004] In order to maximize distance while maintaining accuracy of
a metal wood type golf club head, metal wood type golf clubs have
been designed with the objective of maximizing the distance of a
golf ball struck by a golf club head close to the geometric center
of the golf club head. This geometric center of the golf club head,
due to the inherent laws of physics, may generally produce a golf
shot that maximizes the distance by reducing the energy loss
between the golf ball and the golf club head. In order to quantify
this value, the United States Golf Association (USGA), in
conjunction with the golfing industry, have come up with various
methods such as the calculation the Coefficient of Restitution
(COR) or the calculation of the Characteristic Time (CT) as ways to
quantify the rebounding characteristic of a golf ball after it
impacts a golf club head.
[0005] U.S. Pat. No. 6,390,933 to Galloway et al. ('933 Patent)
discusses one of the methods to increase the COR of a golf club
head by disclosing a golf club head having a coefficient of
restitution greater than 0.845 and a durability to withstand 2000
impacts with a golf ball at 110 miles per hour, wherein the club
head may be composed of three pieces, a face, a sole, and a crown.
More specifically, the '933 Patent discloses a golf club head that
may be composed of a titanium material, having a volume in the
range of 175 cubic centimeters to 400 cubic centimeters, a weight
in the range of 165 grams to 300 grams, and a striking plate
surface area in the range of 4.00 square inches to 7.50 square
inches.
[0006] Focusing on accuracy instead of distance, U.S. Patent
Publication No. 2004/0116202 to Lin ('202 Patent Publication),
discusses a method to increase the accuracy of a golf club head by
disclosing a golf club head having a plurality of holes around the
periphery of the club head, so that when the club head hits the
golf ball, most of the vibration waves and sound waves generated
are dispersed out of these holes thus improving accuracy of the
direction of the striking golf ball.
[0007] However, upon closer examination, we can see that
developments in maximizing distance while maintaining accuracy of a
metal wood type golf club head are premised upon the fact that the
golfer be capable of hitting the golf ball at the sweet spot. It
may be difficult for the average golfer to consistently strike a
golf ball in the sweet spot. Hence, in addition to the performance
factors mentioned above, it may also be desirable to optimize the
size and location of this sweet spot, so an average golfer may
obtain the design benefits of maximizing the distance and accuracy
of the golf club head.
SUMMARY
[0008] The systems, methods, and devices described herein have
innovative aspects, no single one of which is indispensable or
solely responsible for their desirable attributes. Without limiting
the scope of the claims, some of the advantageous features will now
be summarized.
[0009] One aspect of the present technology is the realization that
some golf club head constructions produce a sweet spot which is
offset from the geometric center of the striking face. Thus, there
exists a need for an improved golf club head construction which can
utilize innovating features while focusing the sweet spot about the
geometric center of the striking face. Embodiments disclosed herein
provide golf club head constructions which improve the performance
of golf club heads.
[0010] One non-limiting embodiment of the present technology
includes a golf club head comprising a striking face; a posterior
body portion comprising a crown portion and a sole portion, wherein
said crown portion is coupled to an upper portion of said striking
face and said sole portion is coupled to a lower portion of said
striking face: wherein said striking face comprises: a heel side
and a toe side; a major axis located on said striking face and
oriented substantially from said heel side towards said toe side,
wherein said major axis is the longest line that can be drawn on
said striking face; a minor axis located on said striking face and
oriented substantially from said crown portion towards said sole
portion, wherein said minor axis is the longest line perpendicular
to said major axis that can be drawn on said striking face; a
variable thickness profile comprising: a thick central portion; a
transition portion; and a thin perimeter portion; wherein said
transition portion surrounds said thick central portion; wherein
said thin perimeter portion surrounds said transition portion;
wherein said thick central portion comprises a center, said center
of said thick central portion located equidistant along an axis
parallel to said major axis from a heel most portion of said thick
central portion and a toe most portion of said thick central
portion; wherein said center of said thick central portion is
offset from a geometric center of said striking face along an axis
parallel to said major axis.
[0011] In an additional non-limiting embodiment of the present
technology said center of said thick central portion is offset from
said geometric center towards said toe side of said striking face
at least 2 mm.
[0012] In an additional non-limiting embodiment of the present
technology said center of said thick central portion is offset from
said geometric center towards said toe side of said striking face
at least 3 mm and less than 7 mm.
[0013] In an additional non-limiting embodiment of the present
technology said center of said thick central portion is offset from
said geometric center towards said toe side of said striking face
at least 4 mm and less than 6 mm.
[0014] In an additional non-limiting embodiment of the present
technology a distance H from said center of said thick central
portion to a heel most portion of said transition portion is at
least 1 mm longer than a distance G from said center of said thick
central portion to a toe most portion of said transition portion,
wherein said distance H and said distance G are each measured along
an axis parallel to said major axis.
[0015] In an additional non-limiting embodiment of the present
technology said striking face comprises a sweet spot, said sweet
spot defined by the portion of said striking face capable of
producing at least 99.7% of the maximum resultant ball speed
achievable when a golf ball strikes said striking face, wherein
said sweet spot is substantially centered about said geometric
center of said striking face.
[0016] In an additional non-limiting embodiment of the present
technology |(CT.sub.Toe-0.5''/CT.sub.Center)-1|.ltoreq.0.06 and
|(CT.sub.Heel-0.5''/CT.sub.Center)-1|.ltoreq.0.06, wherein
CT.sub.Center is the CT measurement at said geometric center of
said striking face, CT.sub.Toe-0.5'' is the CT measurement at a
point offset 0.5'' towards said toe side from said geometric center
along an axis parallel to said major axis, and CT.sub.Heel-0.5'' is
the CT measurement at a point offset 0.5'' towards said heel side
from said geometric center along an axis parallel to said major
axis.
[0017] In an additional non-limiting embodiment of the present
technology said thick central portion is substantially elliptical
in shape and substantially constant in thickness, and wherein said
geometric center of said striking face is located at a midpoint of
said minor axis.
[0018] An additional non-limiting embodiment of the present
technology includes a golf club head comprising: a striking face; a
posterior body portion further comprising a crown portion and a
sole portion, wherein said crown portion is coupled to an upper
portion of said striking face and said sole portion is coupled to a
lower portion of said striking face; wherein said striking face
comprises: a heel side and a toe side; a major axis located on said
striking face and oriented substantially from said heel side
towards said toe side, wherein said major axis is the longest line
that can be drawn on said striking face; a minor axis located on
said striking face and oriented substantially from said crown
portion towards said sole portion, wherein said minor axis is the
longest line perpendicular to said major axis that can be drawn on
said striking face; a variable thickness profile comprising: a
thick central portion; a transition portion; and a thin perimeter
portion; wherein said transition portion surrounds said thick
central portion; wherein said thin perimeter portion surrounds said
transition portion; wherein said thick central portion comprises a
center, said center of said thick central portion located
equidistant along an axis parallel to said major axis from a heel
most portion of said thick central portion and a toe most portion
of said thick central portion; wherein said sole portion further
comprises a flexure spaced from said striking face, said flexure
comprising a front wall, an apex, and a rear wall, wherein said
front wall and said rear wall both extend into an interior of said
golf club head, and wherein said front wall and said rear wall are
coupled at said apex; wherein said flexure is offset from a
geometric center of said striking face along an axis parallel to
said major axis; wherein said center of said thick central portion
is offset from said geometric center of said striking face along an
axis parallel to said major axis in substantially the same
direction as said flexure.
[0019] In an additional non-limiting embodiment of the present
technology said flexure comprises a center, said center of said
flexure located equidistant along an axis parallel to said major
axis from a heel most portion of said flexure and a toe most
portion of said flexure, said center of said flexure offset at
least 2 mm from said geometric center of said golf club, and
wherein said center of said thick central portion of said striking
face is offset at least 2 mm from said geometric center of said
golf club.
[0020] In an additional non-limiting embodiment of the present
technology center of said flexure is offset at least 3 mm and less
than 7 mm from said geometric center, and wherein said center of
said thick central portion is offset at least 3 mm and less than 7
mm from said geometric center.
[0021] In an additional non-limiting embodiment of the present
technology said center of said flexure and said center of said
thick central portion are offset substantially the same distance
from said geometric center along an axis parallel to said major
axis.
[0022] In an additional non-limiting embodiment of the present
technology flexure and said thick central portion are both offset
towards said toe side of said striking face.
[0023] In an additional non-limiting embodiment of the present
technology said striking face comprises a sweet spot, said sweet
spot defined by the portion of said striking face capable of
producing at least 99.7% of the maximum resultant ball speed
achievable when a golf ball strikes said striking face, wherein
said sweet spot is substantially centered about said geometric
center of said striking face.
[0024] In an additional non-limiting embodiment of the present
technology |(CT.sub.Toe-0.5''/CT.sub.Center)-1|.ltoreq.0.06 and
|(CT.sub.Heel-0.5''/CT.sub.Center)-1|.ltoreq.0.06, wherein
CT.sub.Center is the CT measurement at said geometric center of
said striking face, CT.sup.Toe-0.5'' is the CT measurement at a
point offset 0.5'' towards said toe side from said geometric center
along an axis parallel to said major axis, and CT.sub.Heel-0.5'' is
the CT measurement at a point offset 0.5'' towards said heel side
from said geometric center along an axis parallel to said major
axis.
[0025] In an additional non-limiting embodiment of the present
technology said thick central portion is substantially elliptical
in shape and substantially constant in thickness, and wherein said
geometric center of said striking face is located at a midpoint of
said minor axis.
[0026] An additional non-limiting embodiment of the present
technology includes a golf club head comprising: a striking face; a
posterior body portion further comprising a crown portion and a
sole portion, wherein said crown portion is coupled to an upper
portion of said striking face and said sole portion is coupled to a
lower portion of said striking face; wherein said striking face
comprises: a heel side and a toe side; a major axis located on said
striking face and oriented substantially from said heel side
towards said toe side, wherein said major axis is the longest line
that can be drawn on said striking face; a minor axis located on
said striking face and oriented substantially from said crown
portion towards said sole portion, wherein said minor axis is the
longest line perpendicular to said major axis that can be drawn on
said striking face; a variable thickness profile comprising: a
thick central portion; a transition portion; and a thin perimeter
portion; wherein said transition portion surrounds said thick
central portion; wherein said thin perimeter portion surrounds said
transition portion; wherein said thick central portion comprises a
center, said center of said thick central portion located
equidistant along an axis parallel to said major axis from a heel
most portion of said thick central portion and a toe most portion
of said thick central portion; wherein said sole portion further
comprises a flexure spaced from said striking face, said flexure
comprising a front wall, an apex, and a rear wall, wherein said
front wall and said rear wall both extend into an interior of said
golf club head, and wherein said front wall and said rear wall are
coupled at said apex; wherein said flexure comprises a toe portion
toeward of a geometric center of said striking face and a heel
portion heelward of said geometric center; wherein either said toe
portion of said flexure or said heel portion of said flexure is
more compliant than the opposite portion; wherein said center of
said thick central portion is offset along an axis parallel to said
major axis towards the more compliant portion of said flexure.
[0027] In an additional non-limiting embodiment of the present
technology said center of said thick central portion of said
striking face is offset at least 2 mm from said geometric
center.
[0028] In an additional non-limiting embodiment of the present
technology said center of said thick central portion is offset at
least 3 mm and less than 7 mm from said geometric center.
[0029] In an additional non-limiting embodiment of the present
technology wherein said center of said thick central portion is
offset at least 4 mm and less than 6 mm from said geometric
center.
[0030] In an additional non-limiting embodiment of the present
technology said striking face comprises a sweet spot, said sweet
spot defined by the portion of said striking face capable of
producing at least 99.7% of the maximum resultant ball speed
achievable when a golf ball strikes said striking face, wherein
said sweet spot is substantially centered about said geometric
center of said striking face.
[0031] In an additional non-limiting embodiment of the present
technology |(CT.sub.Toe-0.5''/CT.sub.Center)-1|.ltoreq.0.06 and
|(CT.sub.Heel-0.5''/CT.sub.Center)-1|.ltoreq.0.06, wherein
CT.sub.Center is the CT measurement at said geometric center of
said striking face, CT.sup.Toe-0.5'' is the CT measurement at a
point offset 0.5'' towards said toe side from said geometric center
along an axis parallel to said major axis, and CT.sub.Heel-0.5'' is
the CT measurement at a point offset 0.5'' towards said heel side
from said geometric center along an axis parallel to said major
axis.
[0032] In an additional non-limiting embodiment of the present
technology said thick central portion is substantially elliptical
in shape and substantially constant in thickness, wherein said
geometric center of said striking face is located at a midpoint of
said minor axis, and wherein said thick central portion is offset
towards said toe side of said striking face from said geometric
center.
[0033] One non-limiting embodiment of the present technology
includes a golf club head comprising a striking face; a posterior
body portion comprising a crown portion and a sole portion, wherein
said crown portion is coupled to an upper portion of said striking
face and said sole portion is coupled to a lower portion of said
striking face; wherein said striking face comprises a heel side and
a toe side; a geometric face center; an impact area centered about
said geometric face center and stretching a distance K towards said
toe side from said geometric face center, and a distance K towards
said heel side from said geometric face center; a toe area
comprising the remainder of said striking on said toe side of said
impact area; a heel area comprising the remainder of said striking
face on said heel side of said impact area; a major axis located on
said striking face and oriented substantially from said heel side
towards said toe side, wherein said major axis is the longest line
that can be drawn on said striking face, said major axis having a
length M; wherein said distance K is determined by dividing said
length M of said major axis by 4.85; wherein a maximum
characteristic time of said striking face occurs outside of said
impact area.
[0034] In an additional non-limiting embodiment of the present
technology a maximum characteristic time of said impact area is
less than or equal to 257 microseconds.
[0035] In an additional non-limiting embodiment of the present
technology a maximum characteristic time of said toe area is less
than or equal to 275 microseconds.
[0036] In an additional non-limiting embodiment of the present
technology a maximum characteristic time of said heel area is less
than or equal to 275 microseconds.
[0037] In an additional non-limiting embodiment of the present
technology a maximum characteristic time of said toe area is
greater than or equal to 257 microseconds.
[0038] In an additional non-limiting embodiment of the present
technology a maximum characteristic time of said heel area is
greater than or equal to 257 microseconds.
[0039] One non-limiting embodiment of the present technology
includes a golf club head comprising a striking face; a posterior
body portion comprising a crown portion and a sole portion, wherein
said crown portion is coupled to an upper portion of said striking
face and said sole portion is coupled to a lower portion of said
striking face; wherein said striking face comprises a heel side and
a toe side; a geometric face center; an impact area centered about
said geometric face center and stretching a distance K towards said
toe side from said geometric face center, and a distance K towards
said heel side from said geometric face center; a toe area
comprising the remainder of said striking on said toe side of said
impact area; a heel area comprising the remainder of said striking
face on said heel side of said impact area; a major axis located on
said striking face and oriented substantially from said heel side
towards said toe side, wherein said major axis is the longest line
that can be drawn on said striking face, said major axis having a
length M; wherein said distance K is determined by dividing said
length M of said major axis by 4.85; wherein said sole portion
comprises a flexure spaced from said striking face, said flexure
comprising a front wall, an apex, and a rear wall, wherein said
front wall and said rear wall both extend into an interior of said
golf club head, and wherein said front wall and said rear wall are
coupled at said apex; wherein a maximum characteristic time of said
striking face occurs outside of said impact area.
[0040] In an additional non-limiting embodiment of the present
technology said flexure comprises a toe portion toeward of a
geometric center of said striking face and a heel portion heelward
of said geometric center; said toe portion of said flexure or said
heel portion of said flexure is more compliant than the opposite
portion; wherein a maximum characteristic time of said striking
face occurs in said toe area if said toe portion of said flexure is
more compliant than said heel portion of said flexure; wherein a
maximum characteristic time of said striking face occurs in said
heel area if said heel portion of said flexure is more compliant
than said toe portion of said flexure.
[0041] In an additional non-limiting embodiment of the present
technology a maximum characteristic time of said striking face
occurs in said toe area.
[0042] One non-limiting embodiment of the present technology
includes a golf club head comprising a striking face; a posterior
body portion comprising a crown portion and a sole portion, wherein
said crown portion is coupled to an upper portion of said striking
face and said sole portion is coupled to a lower portion of said
striking face; wherein said striking face comprises: a heel side
and a toe side; a geometric face center; an impact area centered
about said geometric face center and stretching a distance K
towards said toe side from said geometric face center, and a
distance K towards said heel side from said geometric face center;
a toe area comprising the remainder of said striking on said toe
side of said impact area; a heel area comprising the remainder of
said striking face on said heel side of said impact area; a major
axis located on said striking face and oriented substantially from
said heel side towards said toe side, wherein said major axis is
the longest line that can be drawn on said striking face, said
major axis having a length M; wherein said distance K is determined
by dividing said length M of said major axis by 4.85; a compliant
feature, said compliant feature asymmetrically effecting the
compliance of said striking face about said geometric face center;
wherein a maximum characteristic time of said toe area is greater
than said maximum characteristic time of said heel area.
[0043] In an additional non-limiting embodiment of the present
technology said compliant feature comprises a flexure spaced from
said striking face, said flexure comprising a front wall, an apex,
and a rear wall, wherein said front wall and said rear wall both
extend into an interior of said golf club head, and wherein said
front wall and said rear wall are coupled at said apex; wherein
said flexure comprises a toe portion toeward of a geometric center
of said striking face.
[0044] In an additional non-limiting embodiment of the present
technology said golf club head further comprises a skirt portion at
the intersection of said sole portion and said crown portion and
said flexure is formed in at least a portion of said sole portion
and in at least a portion of said skirt portion.
[0045] In an additional non-limiting embodiment of the present
technology said compliant feature comprises a variable face
thickness profile comprising a thick central portion surrounded by
a transition portion, said transition portion surrounded by a thin
perimeter portion, and wherein the maximum thickness of said thick
central portion, T.sub.thick is at least three times the minimum
thickness of said thin perimeter portion, T.sub.thin.
[0046] In an additional non-limiting embodiment of the present
technology said compliant feature comprises a central face support
element located centrally along a width of said striking face.
[0047] In an additional non-limiting embodiment of the present
technology said central face support element spans at least a
portion of the cavity formed at the interface of said crown portion
and said striking face.
[0048] In an additional non-limiting embodiment of the present
technology wherein said central face support element spans at least
a portion of the cavity formed at the interface of said sole
portion and said striking face.
[0049] In an additional non-limiting embodiment of the present
technology said compliant feature comprises a plurality of central
face support elements located centrally along a width of said
striking face, a first of said plurality of support elements
spanning at least a portion of the cavity formed at the interface
of said crown portion and said striking face, and a second of said
plurality of support elements spanning at least a portion of the
cavity formed at the interface of said sole portion and said
striking face.
[0050] In an additional non-limiting embodiment of the present
technology a maximum characteristic time of said toe area is
greater than or equal to 239 microseconds.
[0051] In an additional non-limiting embodiment of the present
technology a maximum characteristic time of said toe area is
greater than or equal to 257 microseconds.
[0052] In an additional non-limiting embodiment of the present
technology said compliance feature comprises an adjustable weight
capable of manipulating the location of the center of gravity of
said golf club head.
BRIEF DESCRIPTION OF THE DRAWINGS
[0053] The accompanying drawings form a part of the specification
and are to be read in conjunction therewith. The illustrated
embodiments, however, are merely examples and are not intended to
be limiting. Like reference numbers and designations in the various
drawings indicate like elements.
[0054] FIG. 1 illustrates a perspective view of one embodiment of a
golf club head.
[0055] FIG. 2 illustrates a frontal view of a golf club head.
[0056] FIG. 3 is a graphical representation of a typical impact
pattern between a golf club and a golf ball.
[0057] FIG. 4 illustrates a frontal view of a golf club head having
a sweet spot located near the geometric center of the striking
face.
[0058] FIG. 5 illustrates a side view of one embodiment of a golf
club heading includes flexures.
[0059] FIG. 6 illustrates a frontal view of a golf club head
including a flexure and a sweet spot offset from the geometric
center of the striking face.
[0060] FIG. 7 illustrates a side view of one embodiment of a golf
club head including a striking face with a variable thickness
profile and a flexure.
[0061] FIG. 8 illustrates a frontal view of the internal geometry
of the golf club head of FIG. 7.
[0062] FIG. 9 illustrates a frontal view of the internal geometry
of the golf club head of FIG. 7, including a plurality of
relationships regarding the location of portions of the variable
face thickness profile and flexure relative to the geometric center
of the striking face.
[0063] FIG. 10 illustrates a frontal view of one embodiment of a
golf club head having an impact area.
[0064] FIG. 11 illustrates a frontal view of one embodiment of a
golf club head having a flexure.
[0065] FIG. 12 illustrates a frontal view of one embodiment of a
golf club head having a toe flexure and a heel flexure.
[0066] FIG. 13 illustrates a side view of one embodiment of a golf
club head including a striking face with a variable thickness
profile and a flexure.
[0067] FIG. 14 illustrates a side view of one embodiment of a golf
club head including central face support elements.
DETAILED DESCRIPTION
[0068] In the following detailed description, reference is made to
the accompanying drawings, which form a part of the present
disclosure. The illustrative embodiments described in the detailed
description, drawings, and claims are not meant to be limiting.
Other embodiments may be utilized, and other changes may be made,
without departing from the spirit or scope of the subject matter
presented herein. It will be readily understood that the aspects of
the present disclosure, as generally described herein, and
illustrated in the Figures, can be arranged, substituted, combined,
and designed in a wide variety of different configurations, all of
which are explicitly contemplated and form part of this disclosure.
For example, a system or device may be implemented or a method may
be practiced using any number of the aspects set forth herein. In
addition, such a system or device may be implemented or such a
method may be practiced using other structure, functionality, or
structure and functionality in addition to or other than one or
more of the aspects set forth herein. Alterations and further and
further modifications of inventive features illustrated herein, and
additional applications of the principles of the inventions as
illustrated herein, which would occur to one skilled in the
relevant art and having possession of this disclosure, are to be
considered within the scope of the invention.
[0069] Other than in the operating examples, or unless otherwise
expressly specified, all of the numerical ranges, amounts, values
and percentages such as those for amounts of materials, moments of
inertias, center of gravity locations, loft and draft angles, and
others in the following portion of the specification may be read as
if prefaced by the word "about" even though the term "about" may
not expressly appear with the value, amount, or range. Accordingly,
unless indicated to the contrary, the numerical parameters set
forth in the following 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 off reported
significant digits and by applying ordinary rounding
techniques.
[0070] 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.
[0071] In describing the present technology, the following
terminology may have been used: The singular forms "a," "an," and
"the" include plural referents unless the context clearly dictates
otherwise. Thus, for example, reference to an item includes
reference to one or more items. The term "plurality" refers to two
or more of an item. The term "substantially" means that the recited
characteristic, parameter, or value need not be achieved exactly,
but that deviations or variations, including for example,
tolerances, measurement error, measurement accuracy limitations and
other factors known to those of skill in the art, may occur in
amounts that do not preclude the effect the characteristic was
intended to provide. A plurality of items may be presented in a
common list for convenience. However, these lists should be
construed as though each member of the list is individually
identified as a separate and unique member. Thus, no individual
member of such list should be construed as a de facto equivalent of
any other member of the same lists solely based on their
presentation in a common group without indications to the contrary.
Furthermore, where the terms "and" and "or" are used in conjunction
with a list of items, they are to be interpreted broadly, in that
any one or more of the listed items may be used alone or in
combination with other listed items. The term "alternatively"
refers to a selection of one of two or more alternatives, and is
not intended to limit the selection of only those listed
alternative or to only one of the listed alternatives at a time,
unless the context clearly indicated otherwise.
[0072] Features of the present disclosure will become more fully
apparent from the following description and appended claims, taken
in conjunction with the accompanying drawings. After considering
this discussion, and particularly after reading the section
entitled "Detailed Description" one will understand how the
illustrated features serve to explain certain principles of the
present disclosure.
[0073] Embodiments described herein generally relate to golf clubs
having an improved sweet spot. More specifically, some embodiments
relate to golf club head constructions which concentrate the sweet
spot about the geometric center of the golf club head.
[0074] FIG. 1 shows an elevated view of a golf club head 100 in
accordance with an exemplary embodiment of the present invention.
Golf club head 100 shown here in FIG. 1 may generally have a
striking face 102, a posterior body portion 104 and a hosel 105.
The posterior body portion 104 may generally be further comprised
of a crown portion 106, a sole portion (not shown), and a skirt
portion 110. The crown portion 106 may generally be connected to
the upper portion of the striking face 102 while the sole portion
(not shown) may generally be connected to the bottom portion of the
striking face 102. The skirt portion 110, as shown in the current
exemplary embodiment, may generally be juxtaposed between the crown
portion 106 and the sole portion (not shown) to complete the
posterior body portion 104.
[0075] Golf club head 100, as shown in the current exemplary
embodiment depicted by FIG. 1, may generally have a radiused
transition portion 112 at least partially surrounding the perimeter
of the striking face 102. More specifically, as we can see in FIG.
1, the radiused transition portion 112 may be further comprised of
a toe radiused transition portion 114 and a heel radiused
transition portion 116 surrounding the striking face 102 near the
toe and heel portion of the striking face 102 respectively. It
should be noted that although the current exemplary embodiment
shown in FIG. 1 only shows the radiused transition portion 112
covering the toe and heel portion of the golf club head 100, the
radiused transition portion 112 could completely surround the
perimeter of the striking face 102 without departing from the scope
and content of the present invention.
[0076] It should be noted in FIG. 1 that the striking face 102 may
generally have a surface area of greater than about 3600 mm.sup.2,
more preferably greater than about 3700 mm.sup.2, and most
preferably greater than about 3750 mm.sup.2. Additionally, the
radiused transition portion 112 may generally have a surface area
of less than about 850 mm.sup.2, more preferably less than about
825 mm.sup.2, and most preferably less than about 810 mm.sup.2.
Finally, the entire golf club head 100 may generally have a surface
area of between about 32,000 mm.sup.2 and about 35,000 mm.sup.2.
With the surface area value above, it is important to determine the
ratio of the surface area of the striking face 102 relative to the
total area of the entire golf club head 100. This striking face
surface area ratio may generally be greater than about 9%, more
preferably greater than about 10%, and most preferably greater than
about 11%. Alternatively, the above surface areas may also yield a
radiused transition portion surface area ratio. This radiused
transition portion surface area ratio may generally be less than
about 3.0%, more preferably less than about 2.75%, and most
preferably less than about 2.5%.
[0077] FIG. 2 shows a frontal view of a golf club head 200 in
accordance with an exemplary embodiment of the present invention.
This frontal view of the golf club head 200 allows a more direct
view of the striking face 202 showing the striking face 202 being
of a significantly elliptical shape; with a major axis 220 running
in a significantly heel to toe direction and a minor axis 222
running in a significantly crown to sole direction. The striking
face 202 of the golf club head 200 in accordance with an exemplary
embodiment of the present invention may generally have an
elliptical factor greater than about 0.33, more preferably greater
than about 0.41, and most preferably greater than about 0.50. The
elliptical factor discussed above may defined by Equation 1
below:
Elliptical Factor = Length of Minor Axis 222 Length of Major Axis
220 Eq . ( 1 ) ##EQU00001##
[0078] The length of the major axis 220 may generally be defined as
the distance of the longest line that can be drawn on the striking
face 202. Here, in this current exemplary embodiment shown in FIG.
2, the major axis 220 spans in a direction that is significantly
heel to toe; however the major axis 220 could be orientated in any
other direction that deviates from the current orientation so long
it represents the longest line that can be drawn on the striking
face 202 all without departing from the scope and content of the
present invention. Minor axis 222, as shown in the current
exemplary embodiment, may generally be defined as a line across the
striking face 202 that runs perpendicular to the major axis 220,
while passing through the geometric center 201 of the striking face
202. In some embodiments, the geometric center 201 of the striking
face 202 is located at the midpoint of the minor axis 222. In other
embodiments, the geometric center 201 of the striking face 202 is
defined by the center of the impact spot determined by the Impact
Location Template outlined in the Procedure for Measuring the
Flexibility of a Golf Clubhead, USGA-TPX3004, Revision 1.0.0, May
1, 2008 by the United States Golf Association.
[0079] The length of the major axis 220, as shown in the current
exemplary embodiment, may generally be less than about 120 mm
(millimeters), more preferably less than about 110 mm, and most
preferably less than about 100 mm. The length of the minor axis 222
on the other hand, as shown in the current exemplary embodiment,
may generally be greater than about 40 mm, more preferably greater
than about 45 mm, and most preferably greater than about 50 mm.
Hence, it can be seen that when the length of the minor axis 222 is
divided by the length of the major axis 220, the resulting
elliptical factor may generally be within the range discussed
above.
[0080] The frontal view of golf club head 200 shown in FIG. 2 may
also help illustrate how the striking face 202 of the golf club
head 200 is tilted in a more upright position while keeping the
golf club head 200 in a relatively flat position. Alternatively
speaking, the vertical minor axis 222 of the striking face 202 may
generally be tilted at an angle .theta. when compared to a vertical
line 223 that is vertical to the ground 225. The angle .theta., as
shown in the current exemplary embodiment, may generally be greater
than about 3.0 degrees and less than about 16.0 degrees, more
preferably greater than about 3.0 degrees and less than about 12.0
degrees, and most preferably greater than about 3.0 degrees and
less than about 8.0 degrees. As it can be seen from FIG. 2, the
tilting of the striking face 202 of the golf club head 200 relative
to the ground 225 will also cause the major axis 220 and minor axis
222 to tilt to the same extent and in the same direction. Viewed in
another way, the tilt of the striking face 202 may also be defined
as having the major axis 220 and the minor axis 222 both tilted in
a direction of high toe to low heel by an angle of greater than
about 3.0 degrees and less than about 16.0 degrees, more preferably
greater than about 3.0 degrees and less than about 12.0 degrees,
and most preferably greater than about 3.0 degrees and less than
about 8.0 degrees.
[0081] To understand the rationale behind the tilting of the
striking face 202 of the golf club head 200, it may be beneficial
to view FIG. 3 showing the typical impact pattern of a golfer
relative to the striking face 202; with each of the dots on the
graph representing a typical hit location when a golfer hits a golf
ball with a golf club. As it has been reported in F. Werner and R.
Greig, How Golf Clubs Really Work and How to Optimize Their
Designs, Ch. 4, pp. 17-21 (2000), a typical distribution of golf
ball hits on the face of a driver clubs follows an elliptical
pattern with its major axis orientating in a direction from high
toe to low heel, corresponding with the elliptical pattern shown in
FIG. 3. Examining more closely the impact pattern shown in FIG. 3,
we can determine that the major axis 320 of the impact pattern may
form an angle a with the horizontal axis 323. This angle a may
generally coincide with the tilt angle .theta. of the striking face
202 of the golf club head 200 shown in FIG. 2. More specifically, a
may generally be greater than about 3.0 degrees and less than about
16.0 degrees, more preferably greater than about 3.0 degrees and
less than about 12.0 degrees, and most preferably greater than
about 3.0 degrees and less than about 8.0 degrees.
[0082] Returning to FIG. 2, we can see from the hit pattern shown
in FIG. 3 that it may be desirable to tilt the striking face 202 of
the golf club head 200 at an angle .theta. that corresponds to the
tile angle a of the impact pattern. More important than the tilting
of the striking face 202 of the golf club head 200 results in the
tilting of the major axis 220 and the minor axis 222, as tilting
the afore mentioned axes will allow the striking face 202 to be
more in alignment with the typical hit pattern shown in FIG. 3.
[0083] Turning now to FIG. 4, showing another frontal view of a
golf club head, we can see that the golf club head 400 is shown
with a sweet spot 430 located near the geometric center 401 of the
striking face 402 of the golf club head 400. More specifically, the
sweet spot 430 may generally be concentric with the geometric
center 401 of the striking face 402 of the golf club head 400. The
sweet spot 430, within the context of the current application, may
generally be defined as the area of the entire striking face 402
that is capable of achieving at least 99.7% of the maximum
ballspeed achievable by the golf club head 400. The 99.7% value
utilized in determining the size of the sweet spot 430 may be
relevant, because a golf ball that is capable of achieving 99.7% of
the maximum ballspeed only loses about 1/2 a mile per hour of
ballspeed when compared to a direct central hit achieving 100% of
the maximum ballspeed capable by the golf club head 400. The
maximum ballspeed achievable by the golf club head 400, as shown in
the current exemplary embodiment, may generally relate to the
highest ballspeed that can be achieved by the golf club head
regardless of where the golf club head 400 strikes a golf ball.
[0084] In some embodiments, a golf club head can include various
features which may affect the location of the sweet spot relative
to the geometric center of the striking face of the golf club head.
Examples of such features may be found in commonly owned U.S.
patent application Ser. No. 14/089,574 to Golden et al., Golf Club
with Flexure, filed on Nov. 25, 2013, the disclosure of which is
hereby incorporated by reference in its entirety. Flexures 536,
538, as illustrated in FIG. 5 are examples of features which can
shift the sweet spot away from the geometric center of the striking
face. Flexures 536, 538 are generally formed in a forward portion
of the crown, sole, and/or skirt. Flexure 536, is an elongate
corrugation that extends in a generally heel to toe direction and
that is formed in a forward portion of the sole. Flexure 538 is
formed in a forward portion of the crown. Flexures 536, 538 are
generally flexible in a fore/aft direction and provide a flexible
portion of the club head 500 away from the striking face 502 so
that they allow a portion of the striking face 502 to translate and
rotate as a unit, in addition to flexing locally near the point of
impact, when the striking face impacts a golf ball. Flexures 536,
538 can provide improved performance for center face impacts with a
golf ball as well as off-center impacts between the striking face
502 and a golf ball.
[0085] FIG. 6 illustrates a flexure 636, formed in a forward
portion of the sole portion 608. Flexure 636 generally extends
further toeward from the geometric center 601 of the striking face
602 than it extends heelward. Golf club head features, such as the
toe biased flexure 636, can asymmetrically affect the stiffness of
the golf club head 600 and thus effect the location of the sweet
spot 630 on the striking face. FIG. 6 illustrates how flexure 636
has shifted the sweet spot 636 toeward from the geometric center
601 of the striking face 602. Other constructions, features, or
asymmetries in golf club head design may also shift a sweet spot
630 from the geometric center 601 of the golf club head 600.
[0086] As discussed above, it is preferable to locate the sweet
spot at the geometric center of the striking face, as illustrated
in FIG. 4. FIG. 7 illustrates a golf club head 700 in accordance
with an exemplary embodiment of the present invention having a
striking face 702 with a variable face thickness profile 740. Golf
club head 700, as illustrated in FIG. 7, may have a striking face
702 with a variable face thickness profile 740 behind the striking
face 702. More specifically, the variable face thickness profile
740, as shown in the current exemplary embodiment, may generally be
comprised of a thick central portion 742 surrounded by a transition
portion 743, which is then surrounded by a thin perimeter portion
744. Because the striking face 702 of a golf club head 700 deforms
like a trampoline when striking a golf ball, having a variable face
thickness profile 740 allows the thin perimeter portion 744 of the
striking face 702 to be thin enough to provide a trampoline effect
while the thick central portion 742 of the variable face thickness
profile 740 provides sufficient thickness to endure the stresses
associated with a golf ball impact. Because the radiused transition
portion 112 (shown in FIG. 1) may provide additional structural
stiffness to the striking face 702 of the golf club head 700, the
striking face 702 of the golf club head may be made thinner to
create an even bigger sweet spot. More specifically, the increased
structural stiffness may allow the thickness of the thin perimeter
portion 744 to be less than about 3.0 mm thick, more preferably
less than about 2.9 mm thick, and most preferably less than about
2.8 mm thick. More detailed disclosure regarding using variable
face thickness to improve the performance of a golf club head may
be found in U.S. Pat. No. 7,029,403 to Rice et. al., the disclosure
of which is hereby incorporated by reference in its entirety.
[0087] FIG. 7 also illustrates a flexure 736. The flexure 736 is
spaced from the striking face 702. The flexure 736 includes a front
wall 771, a rear wall 772, and an apex 773. The front wall 771 and
rear wall 772 both extend into an interior of the golf club head
700. The front wall 771 and rear wall 772 are coupled at the apex
773.
[0088] FIG. 8 shows a frontal view of the internal geometry of the
golf club head 700 of FIG. 7 with a variable face thickness profile
740. FIG. 8 shows the relative size and position of the thick
central portion 742, the transition portion 743, and the thin
perimeter portion 744. More specifically, FIG. 8 shows the thick
central portion 742 offset from the geometric center 701 of the
striking face 702. As discussed above and illustrated in FIG. 6,
various golf club head constructions or features, such as flexure
636, can create a sweet spot 630 which is not centered on the
geometric center 601 of the striking face. As illustrated in FIG.
8, a striking face 702 incorporating a variable face thickness
profile 740 with a thick central portion 742 offset towards the toe
of the golf club head 700 can provide a sweet spot focused about
the geometric center 701 of the striking face 702. In other
embodiments, the thick central portion 742 may be offset towards
the heel of the golf club head 700. In some embodiments, the thick
central portion 742 is offset in the same direction as a flexure
736, as illustrated in FIG. 8. Locating the thick central portion
742 in a position offset from the geometric center 701 of the
striking face 702, can shift the sweet spot from a less than ideal
position as illustrated in FIG. 6, to a more ideal position focused
about the geometric center 701 of the striking face 702, as
illustrated in FIG. 4, even when the golf club head 700 includes
features which would otherwise shift the sweet spot from the
geometric center 701, such as a flexure 736, as illustrated in
FIGS. 7 and 8.
[0089] FIG. 9 replicates the frontal view of the internal geometry
of the golf club head 700 from FIG. 8, including a plurality of
relationships regarding the location of portions of the variable
face thickness profile 740 and flexure 736 relative to the
geometric center 701 of the striking face 702 to further illustrate
various embodiments of the present invention. As discussed above
and illustrated in FIG. 6, various golf club head constructions or
features, such as flexure 636, can alter the flex characteristics
of the striking face 602 and create a sweet spot 630 which is not
centered on the geometric center 601 of the striking face. FIG. 9
shows that in one embodiment, the flexure 736, or other golf club
head feature, can extend further towards the toe of the golf club
head 700 than the heel of the golf club head 700.
[0090] As illustrated in FIG. 9, the center 737 of the flexure 736,
signified by an X, is offset a Distance A from the geometric center
701 towards the toe of the golf club head. Distance A, along with
Distances B-H discussed below, are measured along an axis parallel
to the major axis 220 as illustrated in FIG. 2 and as discussed
above. The center 737 of the flexure 736 is located substantially
equidistant from the toe most portion of the flexure 736, and the
heel most portion of the flexure 736. Therefore the center 737 of
the flexure 736 is defined by Distance B substantially equaling
Distance C, wherein Distance B is the distance between the center
737 and the toe most portion of the flexure 736 and Distance C is
the distance between the center 737 and the heel most portion of
the flexure 736. In some embodiments, as illustrated in FIG. 9, the
center 737 of the flexure 736 is offset a Distance A toeward from
the geometric center of the club head.
[0091] In some embodiments, Distance A can be between 0.25 mm and
15 mm. In some embodiments, Distance A can be between 1 mm and 10
mm. In some embodiments, Distance A can be between 2 mm and 8 mm.
In some embodiments, Distance A can be between 3 mm and 7 mm. In
some embodiments, Distance A can be between 4 mm and 6 mm. In some
embodiments, Distance A can be greater than 1 mm. In some
embodiments, Distance A can be greater than 2 mm. In some
embodiments, Distance A can be greater than 3 mm. In some
embodiments, Distance A can be greater than 4 mm. In some
embodiments, Distance A can be greater than 5 mm.
[0092] As discussed above in relation to FIGS. 8 and 9, the thick
central portion 742 can be offset from the geometric center 701 of
the striking face 702. FIG. 9 illustrates the center 741 of the
thick central portion 742, signified by an X, offset towards the
toe of the golf club head 700 a Distance D from the geometric
center 701 of the striking face 702. The center 741 of the thick
central portion 742 is located substantially equidistant from the
toe most portion of the thick central portion 742 and the heel most
portion of the thick central portion 742. Therefore the center 741
of the thick central portion 742 is defined by Distance E
substantially equaling Distance F, wherein Distance E is the
distance between the center 741 and the toe most portion of the
thick central portion 742 and Distance F is the distance between
the center 741 and the heel most portion of the thick central
portion 742. In some embodiments, as illustrated in FIGS. 8 and 9,
the golf club head can comprise a flexure 736 with a center 737
offset towards the toe as well as a thick central portion 742 with
a center 741 offset towards the toe. In some embodiments, the
center 741 of the thick central portion 742 can be offset a
Distance D from the geometric center 701, which is substantially
similar to distance A, the distance which the center 737 of the
flexure 736 is offset from the geometric center 701.
[0093] In some embodiments, Distance D can be between 0.25 mm and
15 mm. In some embodiments, Distance D can be between 1 mm and 10
mm. In some embodiments, Distance D can be between 2 mm and 8 mm.
In some embodiments, Distance D can be between 3 mm and 7 mm. In
some embodiments, Distance D can be between 4 mm and 6 mm. In some
embodiments, Distance D can be greater than 1 mm. In some
embodiments, Distance A can be greater than 2 mm. In some
embodiments, Distance D can be greater than 3 mm. In some
embodiments, Distance D can be greater than 4 mm. In some
embodiments, Distance D can be greater than 5 mm.
[0094] As discussed above and as illustrated in FIG. 9, in addition
to a thick central portion 742, the variable thickness profile 740
also includes a transition portion 743, and a thin perimeter
portion 744. In some embodiments, the transition portion 743 is
substantially centered on the thick central portion 742, wherein
Distance G represents the distance from the toe most portion of the
transition portion to the center 741 of the thick central portion
742, H represents the distance from the heel most portion of the
transition portion to the center 741 of the thick central portion
742, and wherein Distance G is substantially equal to Distance H.
In some embodiments, Distance G and Distance H are each between
approximately 15 mm and 30 mm. In some embodiments, Distance G and
Distance H are each between approximately 20 mm and 25 mm. In some
embodiments, Distance G and Distance H are each between
approximately 22 mm and 24 mm. In other embodiments, the transition
portion 743 may not be centered about the thick central portion 742
and Distance G may not equal Distance H. In some embodiments, the
transition portion 743 can be offset towards the heel from the
thick central portion 742 wherein Distance H is greater than
Distance G. In some embodiments, Distance H is at least 1 mm larger
than Distance G. In some embodiments, Distance H is at least 2 mm
larger than Distance G. In other embodiments, Distance G may be
greater than Distance H. In some embodiments, Distance G is at
least 1 mm larger than Distance H. In some embodiments, Distance G
is at least 2 mm larger than Distance H.
[0095] In some embodiments, the center 737 of the flexure 736 may
not be offset from the geometric center 701 of the striking face
702, but may still provide asymmetric stiffness properties,
shifting the sweet spot from the geometric center 701. Asymmetric
stiffness properties can be produced by a plurality of
constructions which may include, for example, asymmetric
proportions, asymmetric thicknesses, asymmetric curvature, hosel
structure, asymmetric ribbing, etc. Therefore, in some embodiments,
the golf club head 701 can include a flexure 736 with a center 737
which is not offset from the geometric center 701, as well as a
thick central portion 742 with a center 741 offset towards the toe
from the geometric center 701. In another embodiment, the center
741 of the thick central portion 742 could be offset towards the
heel. In some embodiments, the center 741 of the thick central
portion 742 could be offset towards the portion of the golf club
head which includes the more compliant portion of the flexure 736
or other golf club head feature.
[0096] One method of measuring the performance of a striking face
is Characteristic Time (CT). Measurement of CT is outlined in the
Procedure for Measuring the Flexibility of a Golf Clubhead,
USGA-TPX3004, Revision 1.0.0, May 1, 2008 by the United States Golf
Association. CT can be measured at various locations on the
striking face 702 of the golf club head 700. CT can be measured at
the geometric center 701 of the striking face 702 (CT.sub.Center).
CT can be measured at a location offset from the geometric center
701 of the striking face 702, such as a point offset 0.5'' towards
the toe from the geometric center 702 along an axis parallel to the
major axis (CT.sub.Toe-0.5''), or a point offset 0.5'' towards the
heel from the geometric center 702 along an axis parallel to the
major axis (CT.sub.Heel-0.5''). In some embodiments, the golf club
head 700 can have a CT relationship wherein
|(CT.sub.Toe-0.5''/CT.sub.Center)-1|.ltoreq.0.06. In some
embodiments, the golf club head 700 can have a CT relationship
wherein |(CT.sub.Heel-0/5''/CT.sub.Center)-1|.ltoreq.0.06.
[0097] For example, one embodiment of a club head could have a
CT.sub.Center value of 235, a CT.sub.Toe-0.5'' value of 247, and a
CT.sub.Heel-0.5'' value of 234. The absolute value of
(CT.sub.Toe-0.5/CT.sub.Center)-1 equals 0.051064 which satisfies
|(CT.sub.Toe-0.5''/CT.sub.Center)-1|.ltoreq.0.06. Also, the
absolute value of (CT.sub.Heel-0.5''/CT.sub.Center)-1 equals
0.012766 which satisfies
|(CT.sub.Heel-0.5''/CT.sub.Center)-1|.ltoreq.0.06. In another
embodiment, the golf club head 700 can have a CT relationship
wherein |(CT.sub.Toe-0.5''/CT.sub.Center)-1|.ltoreq.0.05. In
another embodiment, the golf club head 700 can have a CT
relationship wherein
|(CT.sub.Heel-0.5''/CT.sub.Center)-1|.ltoreq.0.05. In another
embodiment, the golf club head 700 can have a CT relationship
wherein |(CT.sub.Toe-0.5''/CT.sub.Center)-1|.ltoreq.0.04. In
another embodiment, the golf club head 700 can have a CT
relationship wherein
|(CT.sub.Heel-0.5''/CT.sub.Center)-1|.ltoreq.0.04. In another
embodiment, the golf club head 700 can have a CT relationship
wherein |(CT.sub.Toe-0.5''/CT.sub.Center)-1|.ltoreq.0.03. In
another embodiment, the golf club head 700 can have a CT
relationship wherein
|(CT.sub.Heel-0.5''/CT.sub.Center)-1|.ltoreq.0.03.
[0098] It is important to note that a flexure is not the only golf
club head compliant feature that can alter the flex characteristics
of the golf club head when impacting a golf ball. Other compliant
features, which may include for example, variable wall thicknesses,
variable face thickness profiles, curvature, ribbing, weight ports,
hosel structure, etc., can asymmetrically affect the stiffness of a
golf club head and thus effect the location of a sweet spot on the
striking face of the golf club head. The various embodiments of
variable thickness profile as well as shifted thick central
portions discussed herein can be utilized to complement a plurality
of golf club head features in addition to the flexures discussed
herein.
[0099] In another embodiment, a golf club head can be formed from a
plurality of pieces which are joined together to form the golf club
head. In some embodiments, the sole portion and striking face can
be formed from one integral part utilizing a technique called super
plastic forming. Super plastic forming is performed at high
temperatures, and sometimes in a vacuum, to achieve larger than
conventional elongation in a material during the formation process.
The process is especially attractive in the processing of titanium
materials. In some embodiments, a pressurized gas can be used in
place of a male die to form a part rather than a physical die
contacting the surface of the material during deformation. A
pressurized gas can apply a more uniform force while minimizing
localized friction which leads to the formation holes in the
material. Super plastic forming can allow for more complex
geometries to be formed. Super plastic forming also allows for
little to no spring back, aiding in accuracy of manufacture.
Additionally, unlike a casted material, a sole and striking face
formed with super plastic forming has no alpha case or presence of
oxygen on the surface, minimizing surface imperfections, creating a
smooth surface, and minimizing stress crack propagation. In some
embodiments, various features such as the flexure and variable
thickness profile discussed above could be produced using the super
plastic forming process, including for example, the striking face,
the sole, the flexure, and the variable thickness profile.
[0100] As illustrated in FIG. 10, the striking face 1002 of the
golf club head 1000 can include an impact area 1080 outlined by an
impact area perimeter 1082. The impact area 1080 stretches
horizontally a distance K heelward from the geometric center 1001
of the striking face 1002 and a distance K toeward from the
geometric center 1001 of the striking face 1002. Additionally, the
upper limit of the impact area 1080 is offset a distance L from the
perimeter 1003 of the top of the striking face 1000. The lower
limit of the impact area 1080 is offset a distance L from the
perimeter 1003 of the bottom of the striking face 1000. In some
embodiments, distance K can be the radius of a golf ball as per
USGA regulations. In some embodiments, distance K can be 0.84''. In
some embodiments, distance K can be related to the length of the
major axis 220 (illustrated in FIG. 2). In some embodiments,
distance K can be determined by dividing the length of the major
axis by 4. In some embodiments, distance K can be determined by
dividing the length of the major axis by 4.7. In some embodiments,
distance K can be determined by dividing the length of the major
axis by 4.8. In some embodiments, distance K can be determined by
dividing the length of the major axis by 4.85. In some embodiments,
distance K can be determined by dividing the length of the major
axis by 4.9. In some embodiments, distance K can be determined by
dividing the length of the major axis by 5.0. In some embodiments,
distance K can be determined by dividing the length of the major
axis by 6. In some embodiments, distance K can be determined by
dividing the length of the major axis by 7. In some embodiments,
distance L can be 0.25''.
[0101] In some embodiments, club head 1000 can have a measured loft
of 35 degrees or less. In some embodiments, club head 1000 can have
a club head depth exceeding 1.5 inches. In some embodiments, the
striking face 1002 of golf club head 1000 can have a radius of
curvature that is less than or equal to 30 inches.
[0102] As mentioned earlier, one method of measuring the
performance of a striking face is Characteristic Time (CT). CT can
be measured at various locations on the striking face 1002 of the
golf club head 1000. CT values are measured in microseconds.
Generally, CT values will differ at different portion of the
striking face 1002. As illustrated in FIG. 10, the region of the
striking face 1000 toeward of the impact area 1080 is the toe area
1084. The region of the striking face 1000 heelward of the impact
area 1080 is the heel area 1086. The impact area 1080, toe area
1084, and heel area 1086 of the golf club head 1000 each have a
maximum CT value. In some embodiments, the maximum CT value of the
toe area 1084 is greater than the maximum CT value of the impact
area 1080. In some embodiments, the maximum CT value of the heel
area 1086 is greater than the maximum CT value of the impact area
1080. In some embodiments, the maximum CT value of the toe area
1084 and the maximum CT value of the heel area 1086 are both
greater than the maximum CT value of the impact area 1080. In some
embodiments, the maximum CT value of the impact area 1080 is less
than or equal to 239 microseconds and both the maximum CT value of
the toe area 1084 and the maximum CT value of the heel area 1086
are each less than or equal to 257 microseconds. In some
embodiments, the maximum CT value of the impact area 1080 is less
than or equal to 257 microseconds and both the maximum CT value of
the toe area 1084 and the maximum CT value of the heel area 1086
are each less than or equal to 275 microseconds. In some
embodiments, the maximum CT value of the impact area 1080 is less
than or equal to 257 microseconds and both the maximum CT value of
the toe area 1084 and the maximum CT value of the heel area 1086
are each greater than or equal to 257 microseconds. In some
embodiments, the maximum CT value of the toe area 1084 or the
maximum CT value of the heel area 1086 is greater than or equal to
239 microseconds. In some embodiments, the maximum CT value of the
toe area 1084 or the maximum CT value of the heel area 1086 is
greater than or equal to 257 microseconds. In some embodiments, the
maximum CT value of the striking face 1002 is located in either the
toe area 1084 or the heel area 1086.
[0103] Generally, the maximum CT value of a striking face 1002 of a
golf club head 1000 is found in the impact area 1080 rather than
the toe area 1084 or the heel area 1086. However, several golf club
head constructions, some of which described herein, have the
capability of moving the maximum CT value of the striking face 1002
from the impact area 1080 to the toe area 1084 or heel area 1086. A
few examples were illustrated earlier including the flexure
illustrated in FIGS. 5-9 and the variable face thickness portion
illustrated in FIGS. 7-9. Additional examples are illustrated in
FIGS. 11-14.
[0104] FIG. 11 illustrates a golf club head 1100 including a
flexure 1136. The flexure 1136 spans across the majority of both
the toe area 1184 and the heel area 1186. The compliance of the
flexure 1136 is not consistent across the span of the flexure 1136.
The flexure 1136 has a toe portion 1194 adjacent the toe area 1184,
a heel portion 1196 adjacent the heel area 1186, and a center
portion 1190 adjacent the impact area 1180. In this embodiment, the
compliance of the toe portion 1194 of the flexure 1136 and the heel
portion 1196 of the flexure 1136 is greater than the compliance of
the center portion 1190 of the flexure 1136.
[0105] FIG. 12 illustrates golf club head 1200 including a toe
flexure 1236A and a heel flexure 1236B. The toe flexure 1236A is
located adjacent the toe area 1284 and the heel flexure 1236B is
located adjacent the heel area 1286. In some embodiments, as
illustrated in FIG. 12, the toe flexure 1236A can span the skirt
portion 1210 of the golf club head 1000.
[0106] FIG. 13 illustrates a golf club head 1300 with a variable
face thickness profile 1340. The variable face thickness profile
1340, may generally be comprised of a thick central portion 1342,
surrounded by a transition portion 1343, which is then surrounded
by a thin perimeter portion 744. In some embodiments, the thick
central portion has a substantially constant thickness T.sub.thick
and the thin perimeter portion has a substantially constant
thickness T.sub.thin. In some embodiments, the thick central
portion 1342 may not have a substantially constant thickness and
T.sub.thick is the mean thickness of the thick central portion
1342. In some embodiments, the thin perimeter portion 1343 may not
have a substantially constant thickness and T.sub.thin is the mean
thickness of the thin perimeter portion 1343. In some embodiments,
T.sub.thick is the maximum thickness of the striking face and
T.sub.thin is the minimum thickness of the striking face. In some
embodiments the variable thickness ratio, calculated by dividing
T.sub.thick by T.sub.thin, is greater than 2. In some embodiments
the variable thickness ratio, calculated by dividing T.sub.thick by
T.sub.thin, is greater than 2.5. In some embodiments the variable
thickness ratio, calculated by dividing T.sub.thick by T.sub.thin,
is greater than 3. In some embodiments the variable thickness
ratio, calculated by dividing T.sub.thick by T.sub.thin, is greater
than 3.5. In some embodiments the variable thickness ratio,
calculated by dividing T.sub.thick by T.sub.thin, is greater than
4. In some embodiments the variable thickness ratio, calculated by
dividing T.sub.thick by T.sub.thin, is greater than 4.5. In some
embodiments the variable thickness ratio, calculated by dividing
T.sub.thick by T.sub.thin, is greater than 5. In some embodiments
the variable thickness ratio, calculated by dividing T.sub.thick by
T.sub.thin, is greater than 5.5. In some embodiments the variable
thickness ratio, calculated by dividing T.sub.thick by T.sub.thin,
is greater than 6.
[0107] FIG. 14 illustrates a golf club head 1400 including central
face support elements 1490A, 1490B. The golf club head 1400 can
include one or more central face support elements 1490A, 1490B. The
upper central face support element 1490A can span at least a
portion of the cavity formed at the interface of the crown portion
1406 and the striking face 1402. The lower central face support
element 1490B can span at least a portion of the cavity formed at
the interface of the sole portion 1408 and the striking face 1402.
The central face support elements 1490A, 1490B, are centrally
located in the golf club head. The central face support elements
1490A, 1490B, are located between the toe area and the heel area,
adjacent the impact area. The central face support elements 1490A,
1490B aid in stiffening the impact area of the face relative to the
toe area and heel area. In some embodiments, the central face
support elements 1490A, 1490B have a thickness measured along the
major axis. In some embodiments, the thickness of the central face
support elements can be greater than or equal to 0.3 mm and less
than or equal to 50 mm. The central face support elements 1490A,
1490B can also be substantially triangular in shape as illustrated
in FIG. 14. The length of the hypotenuse of the triangularly shaped
central face support elements 1490A, 1490B can be greater than or
equal to 1 mm and less than or equal to 12 mm.
[0108] One final example of a golf club head construction which can
move the maximum CT value of the striking face from the impact area
to the toe area or heel area includes moveable and/or adjustable
weights. By manipulating the center of gravity of the golf club
head by either adjusting, adding, or removing one or more weights
associated with the golf club head, the locating of the maximum CT
on the striking face of the golf club head can be manipulated. In
some embodiments, shifting the center of gravity of the golf club
head towards the heel area will increase the maximum CT of the heel
area. In some embodiments, shifting the center of gravity of the
golf club head towards the toe area will increase the maximum CT of
the toe area.
[0109] In describing the present technology herein, certain
features that are described in the context of separate
implementations also can be implemented in combination in a single
implementation. Conversely, various features that are described in
the context of a single implementation also can be implemented in
multiple implementations separately or in any suitable sub
combination. Moreover, although features may be described above as
acting in certain combinations and even initially claimed as such,
one or more features from a claimed combination can in some cases
be excised from the combination, and the claimed combination may be
directed to a sub combination or variation of a sub
combination.
[0110] Various modifications to the implementations described in
this disclosure may be readily apparent to those skilled in the
art, and the generic principles defined herein may be applied to
other implementations without departing from the spirit or scope of
this disclosure. Thus, the claims are not intended to be limited to
the implementations shown herein, but are to be accorded the widest
scope consistent with this disclosure as well as the principle and
novel features disclosed herein.
* * * * *