U.S. patent application number 10/338054 was filed with the patent office on 2004-07-08 for golf club head.
Invention is credited to Doi, Douglas Alan.
Application Number | 20040132544 10/338054 |
Document ID | / |
Family ID | 32681363 |
Filed Date | 2004-07-08 |
United States Patent
Application |
20040132544 |
Kind Code |
A1 |
Doi, Douglas Alan |
July 8, 2004 |
Golf club head
Abstract
A golf club driver head comprised of a hollow body shell of a
standard golf club driver shape. This shape has a front impact face
plate, a bottom sole plate, a top crown shell, a curved rear wall,
a heel, a toe, and a cylindrical hosel, which extends from the
face, crown, and heel junction to attach to a shaft. This body is
composed completely from cast or machined billet magnesium alloy.
The body shell thickness is generally thicker than that in
equivalent locations of metallic and other alloy driver heads of
the same head volume. The face plate is thicker than that in the
remainder of the body to provide a lower deflection surface,
improve durability, and to maintain a forward center of gravity.
The result of such a large head is a much larger hitting sweet spot
and corresponding increased driver accuracy and control.
Inventors: |
Doi, Douglas Alan; (San
Marcos, CA) |
Correspondence
Address: |
Douglas Alan Doi
724 Avenida Leon
San Marcos
CA
92069
US
|
Family ID: |
32681363 |
Appl. No.: |
10/338054 |
Filed: |
January 8, 2003 |
Current U.S.
Class: |
473/345 ;
473/305; 473/346; 473/349 |
Current CPC
Class: |
A63B 53/0462 20200801;
A63B 2209/00 20130101; A63B 53/0412 20200801; A63B 53/0416
20200801; A63B 53/0466 20130101; A63B 53/0458 20200801; A63B 53/045
20200801; A63B 53/0408 20200801 |
Class at
Publication: |
473/345 ;
473/349; 473/346; 473/305 |
International
Class: |
A63B 053/04; A63B
053/02 |
Claims
I claim:
1. A golf club head, comprising: (a) a complete body, the body
having a front impact face plate, a bottom sole plate, a top crown
shell, a curved rear wall, a heel, a toe, and a hollow hosel which
extends upward from the face/crown/heel junction at a predetermined
angle for attaching said golf club head to a shaft; (b) said body
and hosel being formed entirely of cast or machined billet
magnesium alloy; (c) said front impact face plate having a
thickness which varies across its area and is thickest at the
center of the impact face plate while generally thinnest around the
periphery of the impact face plate; (d) said impact face plate
being thicker at the heel area than the toe area while having no
bottom versus top thickness bias.
2. The golf club head as in claim 1, wherein the body is cast or
machined in two parts. The first part comprises the complete shell
of the head with the exception of which the bottom sole plate has
an opening extending over the majority of its surface. The second
part is a separate sole plate, which is welded flush around the
periphery of the bottom opening of the first part.
3. The 370 cc baseline golf club head as claimed in claim 1,
wherein the thickness of the impact face plate is between 0.200 and
0.280 inches (0.160 inches and 0.224 inches respectively for the
505 cc version).
4. The 370 cc baseline golf club head as claimed in claim 1,
wherein the wall thickness at the center of the impact face plate
is approximately 0.270 inches (0.216 inches for the 505 cc
version).
5. The 370 cc baseline golf club head as claimed in claim 1,
wherein the wall thickness at the side edges of the impact face
plate is in the range from 0.200 to 0.280 inches (0.160 inches and
0.224 inches respectively for the 505 cc version).
6. The 370 cc baseline, golf club head as claimed in claim 1,
wherein the wall thickness at the lower and upper edges of the
impact face plate ranges from 0.200 to 0.235 inches (0.160 inches
and 0.188 inches respectively for the 505 cc version).
7. The 370 cc baseline golf club head as claimed in claim 1,
wherein the wall thickness of the top crown shell is between 0.10
and 0.14 inches (0.09 inches and 0.11 inches respectively for the
505 cc version).
8. The 370 cc baseline golf club head as claimed in claim 1,
wherein the thickness of the sole plate is between 0.12 and 0.20
inches (0.09 inches and 0.09 inches respectively for the 505 cc
version).
9. The 370 cc baseline golf club head as claimed in claim 1,
wherein the thickness of the toe is between 0.12 and 0.47 inches
(0.10 inches and 0.37 inches respectively for the 505 cc version);
the front most thickness of the toe being 0.47 (0.37 inches for the
505 cc version) to provide boss material for heavy material like
lead or tungsten to be inserted.
10. The 370 cc baseline golf club head as claimed in claim 1,
wherein the thickness of the back wall is between 0.11 and 0.12
inches (0.09 inches and 0.09 inches respectively for the 505 cc
version).
11. The 370 cc baseline golf club head as claimed in claim 1,
wherein the thickness of the heel is between 0.11 and 0.14 inches
(0.09 inches and 0.10 inches respectively for the 505 cc
version).
12. The golf club head as claimed in claim 1, wherein the outside
diameter of the hosel is approximately 0.66 inches and has a
0.337-inch diameter hole for insertion of a standard wood golf
shaft. Standard 45-degree hosel chamfer and inner channels (Five
V-channeled rings, cut 0.01 inches deep and placed 0.22 inches
apart). Starting from about the horizontal centerline to the bottom
of the heel, the hosel outside diameter tapers from 0.66 inches to
approximately 0.50 inches respectively.
13. The golf club head as claimed in claim 1, wherein the face has
three ribs, one placed vertically in the center of the face and the
others each 1 inch (1.25 inches for the 505 cc version) on each
side of this central rib. The ribs are of 0.125 inches thickness
with about a 0.25 inches (0.30 inches for the 505 cc version)
depth. The head is formed completely form a light weight alloy
magnesium metal, which is at least 77% lighter in weight than
steel, 60% lighter than titanium and 33% lighter than aluminum:
3 Magnesium Density Density % Material lb./in.{circumflex over (
)}3 lb./in.{circumflex over ( )}3 Lighter Steel 0.284 0.066 77%
Titanium 0.164 0.066 60% Aluminum 0.098 0.066 33%
The front impact face plate has an average thickness of
approximately two times that of the remainder of the head. The
thickness of the impact face plate varies from its outer perimeter
towards its geometrical center; the impact face plate is thickest
at its center and generally thinner around the periphery of the
impact face plate.
14. The golf club head as claimed in claim 1, wherein the inner
corners have rounded fillets and the outer corners are rounded.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates to the golf club head of the wood
driver type.
[0002] Golf clubs are generally categorized into four main types,
drivers, irons, putters and specialty. The traditional driver was
made of wood, so the terminology "wood" has become synonymous with
the driver, irrespective of its material composition. The wood
drivers were made of solid wood and were typically of volumes 200
cc and smaller. Recent advances in manufacturing methodologies and
material science have enabled the invention of drivers comprised of
steel, alloy and composite materials. Because of the material
properties and evolution of manufacturing (casting, forging and
welding techniques and technology), the steel and alloy drivers are
fabricated as hollow shells. Subsequently, the heads of wood
drivers have evolved into a classic shape that includes a slightly
curved impact face plate, a curved sole plate, an upper crown
shell, a heel, a to and a rear wall. During the past decade these
hollow driver heads have also evolved in volume, from approximately
200 cc to 360 cc, yet maintained the approximate 200 gram mass. The
reason for the demand for increasing head volume is a larger impact
face plate area and larger sweet spot due to the larger polar
moment of inertia. However, the wall thicknesses of steel and
titanium alloy heads have also become increasingly thin to match a
corresponding increase in volume. The impact face plate for these
large steel and titanium heads are now thinner than 0.10 inches and
are unable to maintain their form and meet regulatory requirements
for coefficients of restitution during impact with the golf ball.
This has resulted in reduced control of launch angle at impact as
well as non-compliance status labeling by major golf governing
organizations.
[0003] In light of the current manufacturing and material
technology, the steel and titanium heads are limited in size to the
300 cc to 360 cc range if it is desired to meet current functional
and regulatory requirements.
SUMMARY OF THE INVENTION
[0004] It is an object of this invention to provide a wood driver
golf club head which improves the forgiveness of the off-centered
impact and increases the sweet spot through the use of magnesium
alloy to increase the volume of the head to the 370 cc to 505 cc
range and larger.
[0005] The present invention comprises a golf club head which is an
empty, hollow body shaped in the form of a golf club driver head,
the body formed entirely of cast or machined billet magnesium
alloy, the body also having a front impact face plate, a bottom
sole plate, an upper crown shell, a curved rear wall, a heel, a
toe, and a hollow neck extending upwardly from the face/crown/heel
junction of the body at a predetermined angle, and the front impact
face plate having an average thickness of 0.23 inches (in the 370
cc baseline configuration). The walls of the hollow magnesium body
can be made thicker than those of a standard steel or titanium golf
club head, because magnesium is approximately 77% lighter than
steel, 60% lighter than titanium and 33% lighter than aluminum.
This added thickness decreases the face deflection at impact,
resulting in a more controlled trajectory. This increased thickness
also gives a more solid feel at impact and reduces noise and
vibration. The thicker material also provides a boss for the
insertion of a more dense material to provide better ballasting and
tuning to the individual preference of the player. The head volume
can be greater than that of a steel or titanium head because of the
lighter material used, resulting in a much larger sweet spot and
less face deflection during impact. In the preferred embodiment of
the invention, the overall head dimensions can be more than 20%
larger than those of the largest steel or titanium driver club
head.
[0006] The impact face plate thickness distribution is integral to
the structural integrity of the head during impact with the golf
ball. The wall has a vertical thickness bias to the height
corresponding with the head's center of gravity. At the
cross-sectional plane made by the longitudinal and vertical
centerlines, the impact face plate thickness is 0.21 inches, 0.27
inches, and 0.21 inches for the top, middle and bottom respectively
(corresponding to T3B, T2B and T1B respectively in drawing 5). This
thickness distribution provides the most material at the center of
the sweet spot, to decrease the localized face deflection and
decrease localized bending stresses. The wall also has a horizontal
thickness bias that decreases with distance from the hosel. At the
cross-sectional plane made by the longitudinal and horizontal
centerlines, the impact face plate thickness is 0.28 inches, 0.27
inches, and 0.21 inches for the heel side, middle and toe side
respectively (corresponding to T2A in drawing 4, T2B in drawing 5,
and T2C in drawing 6 respectively). This distribution decreases the
overall bending and improves the feel at impact.
[0007] The lighter material also provides excess material for
ribbing on the backside of the impact face plate. This ribbing is
typically 0.25 inches deep and 0.125 inches wide. The base
configuration is three vertical ribs, the first rib located in the
middle of the impact face plate with the remaining two ribs 1 inch
on the left and right (drawing 10). The alternative "web" ribbing
adds more ribs to create a grid of triangular patterns (drawing
11). This ribbing provides more bending strength and reduces
material stress at impact.
[0008] Because the forward portion of the bottom sole plate can
come into direct contact with the ball and/or the ground, the plate
is thicker in the forward location relative to that of the aft
portion of the plate. The top crown shell is similarly proportioned
because with severe miss-struck shots, it can directly impact the
ball. The back wall is as thin as the casting or machining
technology will allow.
[0009] There are two locations on the head that allow for ballast
material. This ballast material can be lead, tungsten or other
malleable, dense material. The first ballast location is in the
hosel, which is a standard location in the inner hosel below the
tip of the shaft. The second ballast location is in the toe, where
there is a boss that can be drilled and ballast material inserted.
Varying amounts of ballast material such as tungsten or lead can be
added or removed to increase or decrease the center of gravity (CG)
height of the head. These two ballasting locations are in the
forward part of the head. This allows the location of the head CG
to be adjusted vertically and horizontally, while maintaining a
forward location. This ballasting also provides a spectrum of
swingweights necessary to satisfy the requirements of golfers based
on their skill and strength level, without significantly altering
the characteristics or weight distribution of the head.
DESCRIPTION OF THE DRAWINGS
[0010] The invention will be graphically described from the
following drawings. These drawings were produced from the detailed
three-dimensional mathematical computer aided design model that was
used to fabricate actual driver head components. Drawings 1-3 will
give the basic views of the head while drawings 4-11 show the
corresponding cut sections and drawings. The vertical, horizontal
and longitudinal centerlines intersect at the head center of
gravity:
[0011] Drawing 1 is a front elevation view of a golf club driver
head according to the baseline configuration of the invention;
[0012] Drawing 2 is the left side elevation view of the head;
[0013] Drawing 3 is a top plan view of the head;
[0014] Drawing 4 is a cross-section on the lines A-A of Drawing
3;
[0015] Drawing 5 is a cross-section on the lines B-B of Drawing
3;
[0016] Drawing 6 is a cross-section on the lines C-C of Drawing
3;
[0017] Drawing 7 is a cross-section on the lines D-D of Drawing
3;
[0018] Drawing 8 is a cross-section on the lines E-E of Drawing
3;
[0019] Drawing 9 is a cross-section on the lines F-F of Drawing
3;
[0020] Drawing 10 is a cross-section on the lines E-E of Drawing 3
which shows the baseline rib configuration;
[0021] Drawing 11 is a cross-section on the lines E-F of Drawing 3
which shows the alternative rib configuration.
DESCRIPTION OF THE PREFERRED CONFIGURATION
[0022] Drawings 1, 2, 3 describe the golf club driver head
according to the baseline configuration of the present invention.
The head can be described as a hollow shell body of cast or
machined magnesium alloy, having a front impact face plate 1 an
upper crown shell 2, a bottom sole plate 3, a heel 4, a toe 5, a
rear curved shell 6, and a hollow hosel 7 extending from the
face/crown/heel junction at a specified angle for the insertion of
the golf club shaft (not illustrated). The head has the shape of a
conventional golf club driver head, but is of larger dimensions
than conventional large-headed drivers.
[0023] The size of the head ranges from 370 cc to 505 cc and
greater, which is larger than that of a standard titanium or steel
driver head producing a corresponding increase in the sweet spot
and reducing the number of miss-struck shots. The face thickness is
increased to improve durability and decrease localized face
deflection, which increases the predictability and consistency of
the shot. In addition to a larger head and sweet spot, the weight
of the 370 cc baseline head is about 185 grams, which is less than
that of a standard titanium head. This weight allows for the
addition of up to 20 grams ballast weight in the hosel and the toe
of the head to allow for horizontal and vertical adjustment of the
center of gravity. In the 370 cc baseline configuration of the
invention, the impact face plate is 2.25 inches high and 5 inches
wide.
[0024] Drawings 4, 5 and 6 illustrate the variation of thickness of
the impact face plate over its area for the 370 cc baseline
configuration. The impact face plate has an average thickness of
0.23 inches, whereas the remainder of the body has a wall thickness
between 0.09 inches and 0.15 inches. Thus, the impact face plate
contains the most material of any wall and the weight and center of
gravity is closer to the front of the head, which improves the
ball-striking properties. The impact face plate is not of uniform
thickness but is generally thicker in the sweet spot corresponding
to the CG height and head center. This wall contour is designed to
decrease the localized material stresses, improve durability, and
move the center of gravity closer to the front of the striking
face. The various thickness dimensions indicated in drawings 4, 5,
6 in the baseline configuration of the invention are given below in
inches:
1 370 cc Baseline Configuration (inches): T1A = 0.235 T1B = 0.220
T1C = 0.200 T2A = 0.280 T2B = 0.270 T2C = 0.235 T3A = 0.235 T3B =
0.220 T3C = 0.200 T4A = 0.105 T4B = 0.125 T4C = 0.120 T5A = 0.110
T5B = 0.115 T5C = 0.120 T6A = 0.120 T6B = 0.120 T6C = 0.120
[0025]
2 505 cc Version (inches): T1A = 0.188 T1B = 0.176 T1C = 0.160 T2A
= 0.224 T2B = 0.216 T2C = 0.188 T3A = 0.188 T3B = 0.176 T3C = 0.160
T4A = 0.100 T4B = 0.095 T4C = 0.090 T5A = 0.090 T5B = 0.090 T5C =
0.090 T6A = 0.090 T6B = 0.090 T6C = 0.090
[0026] To reduce stresses at the inside corners, radius fillets are
applied. As a practical precaution to cutting or scraping items the
club may incidentally come into contact with, the outer corners are
sanded or ground to a radius. The front curvature of the impact
face plate is relatively large over its entire area to provide a
large striking area. This further increases the sweet spot and
results in a head that produces improved accuracy for miss-struck
shots. The maximum thickness of 0.28 inches (in the 370 cc baseline
configuration) is located at the horizontal centerline of the
striking face on the hosel side, while the minimum thickness is
0.09 inches (in the 370 cc baseline configuration) at the back
wall.
[0027] Drawings 7, 8, 9 ate the horizontal cut-sections D, E, F
corresponding to the forward, middle and rear respectively. These
drawings show the hosel and the wall thickness of the crown, sole,
heel and toe. Drawing 7 cuts through the hosel, showing the
following:
[0028] Interior Threads: For the increased retention of the shaft
to the head 8
[0029] Interior Chamfer: For the reduction of the point contact
load of the end of the hosel with the shaft 9
[0030] Weight Ballast Compartment: For the addition of a standard
lead weight located at the tip of the shaft 10
[0031] Drawing 7 also shows the wall thickness of the toe to be
thicker than is structurally required during impact, but this
material acts as a boss for the insertion of a soft malleable metal
extrusion or screw made from material such as tungsten, brass or
lead.
[0032] Drawings 7, 8 and 9 show how the wall thickness of the sole,
crown, heel and toe tapers from front to back. This tapering
maintains the forward location of the center of gravity of the head
as well as reduces the overall head weight to allow for a larger
total volume of the head.
[0033] Drawings 10 and 11 show the baseline and alternate
configuration respectively of the ribbing behind the front impact
face plate. These ribs provide added strength to the face to reduce
total deflection upon impact resulting in increased control on
miss-struck shots.
[0034] By manufacturing the hollow shell of the golf club head
completely of lightweight magnesium or magnesium alloy, the weight
distribution can be improved by increasing the overall impact face
plate thickness and optimally varying the thickness. This also
moves the center of gravity forward, closer to the impact face
plate. In addition, the total volume of the head can be increased,
which results in a corresponding increase in the sweet spot and
improved control and distance with miss-struck shots. The wall
thickness over the entire body can be increased, resulting in
increased structural rigidity and reduced vibration upon impact
with the golf ball.
[0035] The two locations of weight adjustment in the toe and the
hosel allow for the adjustment of the CG location in the vertical,
horizontal and longitudinal direction in addition to providing
swing weights to accommodate the personal requirements of golfers
of every power and skill level.
[0036] Though the baseline and alternative configurations of the
invention have been described by explicit detail, it will be
understood by those in the golf industry that alternative
configurations of and modifications to the disclosed invention
still are within the scope of the invention, which is defined by
the following claims:
* * * * *