U.S. patent application number 17/035734 was filed with the patent office on 2021-04-08 for golf club.
This patent application is currently assigned to K.K. ENDO SEISAKUSHO. The applicant listed for this patent is K.K. ENDO SEISAKUSHO. Invention is credited to Makoto Okada.
Application Number | 20210101054 17/035734 |
Document ID | / |
Family ID | 1000005121707 |
Filed Date | 2021-04-08 |
United States Patent
Application |
20210101054 |
Kind Code |
A1 |
Okada; Makoto |
April 8, 2021 |
GOLF CLUB
Abstract
Provided is a golf club which allows for hitting a golf ball
long distance and enhancing the durability of the golf club. The
golf club has: a body portion welded and integrally attached with a
face portion made of a rolled material. A back surface of the face
portion has at least one groove provided at a location lower than a
center of gravity on a striking face of the face portion. The at
least one groove is extending from a proximity of a toe portion to
a proximity of a heel portion. Moreover, three grooves can be
provided evenly spaced apart along a direction intersecting with a
direction heading from the toe portion to the heel portion.
Inventors: |
Okada; Makoto; (Niigata,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
K.K. ENDO SEISAKUSHO |
Niigata-ken |
|
JP |
|
|
Assignee: |
K.K. ENDO SEISAKUSHO
Niigata-ken
JP
|
Family ID: |
1000005121707 |
Appl. No.: |
17/035734 |
Filed: |
September 29, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A63B 53/0445 20200801;
A63B 53/047 20130101; A63B 2102/32 20151001; A63B 53/0416
20200801 |
International
Class: |
A63B 53/04 20060101
A63B053/04 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 4, 2019 |
JP |
2019-183578 |
Claims
1. An iron type golf club, comprising: a body portion, having: a
sole portion at a bottom section to be put on a ground, a topline
portion at an upper section, a toe portion at a front section, a
heel portion at a rear section, and a hosel portion configured to
attach the body portion to a shaft; and a face portion, being
welded with the body portion and having a striking face for hitting
a golf ball, wherein a back surface of the face portion has a
plurality of grooves being provided at a location lower than a
center of gravity on the striking face of the face portion to
extend in lines parallel to each other and evenly spaced apart from
a proximity of the toe portion to a proximity of the heel
portion.
2-3. (canceled)
4. The iron type golf club according to claim 1, wherein the plural
grooves are provided through a stamping operation.
5. The iron type golf club according to claim 4, wherein the face
portion is made of a rolled material rolled along a direction
heading from the topline portion to the sole portion in a rolling
operation.
6. The iron type golf club according to claim 5, wherein the body
portion is made of a low-carbon forged steel.
7. The iron type golf club according to claim 6, wherein each of
the plural grooves has 0.4 mm in depth and a semi-arc shape in
cross-section, and the face portion has a thickness to be less than
or equal to 2.1 mm.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority benefit of Japanese
Patent Application No. 2019-183578, filed on Oct. 4, 2019. The
entirety of the above-mentioned patent application is hereby
incorporated by reference herein and made a part of this
specification.
TECHNICAL FIELD
[0002] This present disclosure relates to a metal golf club, and
more particularly, to a golf club which allows for hitting a golf
ball long distance and enhancing the durability of the golf
club.
BACKGROUND ART
[0003] A performance required for a golf club has been generally
like that, a long distance that a golf ball can fly is for a wood
type golf club which represents a driver, while a desired target
point a golf ball can reach is for an iron type golf club. The iron
type golf club (hereinafter referred to as "the iron"), however,
has been recently required for a long distance that a golf ball can
fly, as well as the wood type golf club. A golf club disclosed in
the undermentioned Patent Document 1 has grooves curved at the same
direction at least either of the crown portion or the sole portion,
thus allowing for an increased coefficient of restitution of the
golf club head, thereby permitting a golf ball to fly a longer
distance. On the other hand, a golf club disclosed in the
undermentioned Patent Document 2 has the thickness of the face
portion to be thin and the ribs formed extending to the back
surface of the face portion from the rear portion of the golf club
head, whereby to prevent the launch velocity of a golf ball from
varying over the total part of the face portion of the golf
club.
[0004] For the iron as well as a wood type golf club, the increased
coefficient of restitution (COR) is also thought to be an effective
means for hitting a golf ball long distance. To increase the
coefficient of restitution (COR) of a golf club, it is necessary to
make a face portion of the golf club to easily flex or deflect upon
impact with a golf ball during golf swing. To make the face portion
to easily flex or deflect upon impact with a golf ball during golf
swing, there are known three approaches such as: (1) to make the
thickness of the face portion club to be thinner, (2) to make the
young's modulus of the face portion to be smaller, and (3) to make
the area of the face portion to be larger. Among the
above-mentioned three approaches, the second approach is difficult
because the young's modulus is the characteristic value of the
material and an iron-based material is mainly used as the material
of the iron. The third approach is not preferred because the iron
to hit a golf ball on the ground possibly has the center of gravity
to be shifted more upward on the face portion. Therefore, the first
approach is preferred the most. The first approach to make the
thickness of the face portion to be thinner, however, has another
problem to deteriorate durability of the face portion of the golf
club. Therefore, the conventional iron has not satisfied both of
increasing the coefficient of restitution of the golf club head to
hit the golf ball longer distance and enhancing the durability of
the face portion of the golf club head.
[0005] Patent Document 1: JP 2018-143523A
[0006] Patent Document 2: JP 3220762 (Utility)
SUMMARY OF THE INVENTION
[0007] The present disclosure has been achieved to solve the
problems of the prior art as mentioned above. The present
disclosure provides a golf club which allows for hitting a golf
ball long distance and enhancing the durability of the golf
club.
[0008] The present disclosure provides a golf club which has a body
welded integrally with a face portion made of high-strength
material to enhance the durability of the face portion.
[0009] The present disclosure provides a golf club which has a back
surface of a face portion formed with grooves extending from a
proximity of a toe portion to a proximity of a heel portion, thus
causing the face portion to easily flex or deflect and to thereby
increase the coefficient of restitution of the face portion.
[0010] The present disclosure provides a golf club which has a back
surface of a face portion stamped to form grooves, to thereby
enhance the durability of the face portion.
[0011] In order to solve the above-mentioned problems, according to
a first embodiment of the present disclosure, a golf club is a
metal golf club, and the golf club includes: a body portion,
having: a sole portion at a bottom section to be put on a ground, a
topline portion at an upper section, a toe portion at a front
section, a heel portion at a rear section, and a hosel portion
configured to attach the body portion to a shaft; and a face
portion, being welded with the body portion and having a striking
face for hitting a golf ball. A back surface of the face portion
has at least one groove, being provided at a location lower than a
center of gravity on the striking face of the face portion and
extending from a proximity of the toe portion to a proximity of the
heel portion.
[0012] A golf club according to a second embodiment of the present
disclosure is within the first embodiment of the present
disclosure, in which the at least one groove includes plural
grooves, and the plural grooves are provided parallel to each other
along a direction intersecting with a direction heading from the
toe portion to the heel portion.
[0013] A golf club according to a third embodiment of the present
disclosure is within the second embodiment of the present
disclosure, in which the plural grooves are provided evenly spaced
apart along the direction intersecting with the direction extending
from the toe portion to the heel portion.
[0014] A golf club according to a fourth embodiment of the present
disclosure is within the third embodiment of the present
disclosure, in which the plural grooves are provided through a
stamping operation.
[0015] A golf club according to a fifth embodiment of the present
disclosure is within the fourth embodiment of the present
disclosure, in which the face portion is made of a rolled material
rolled along a direction heading from the topline portion to the
sole portion in a rolling operation.
[0016] A golf club according to a sixth embodiment of the present
disclosure is within the fifth embodiment of the present
disclosure, in which the body portion is made of a low-carbon
forged steel.
[0017] A golf club according to a seventh embodiment of the present
disclosure is within the sixth embodiment of the present
disclosure, in which each of the grooves has 0.4 mm in depth and a
semi-arc shape in cross-section, and the face portion has a
thickness to be less than or equal to 2.1 mm.
[0018] A golf club according to the present disclosure includes: a
back surface of a face portion, having at least one groove which is
provided at a location lower than a center of gravity on a striking
face of the face portion and are extending from a proximity of a
toe portion to a proximity of a heel portion, whereby causing the
face portion to easily flex or deflect and to thereby increase the
coefficient of restitution, which results in allowing for hitting a
golf ball long distance.
[0019] A golf club according to the present disclosure also allows
for enhancing the durability of the golf club head, because the
grooves are provided through a stamping operation.
BRIEF DESCRIPTIONS OF DRAWINGS
[0020] FIGS. 1A and 1B are overall views to show a golf club in
accordance with a first embodiment of the present disclosure. FIG.
1B is a front view of the golf club. FIG. 1A is a left side view of
FIG. 1B.
[0021] FIG. 2 is a cross-sectional view taken along section lines
A-A in FIG. 1B.
[0022] FIG. 3 is a cross-sectional view taken along section lines
B-B in FIG. 2.
[0023] FIGS. 4A and 4B are elevated cross-sectional views in P
portion of FIG. 2. FIG. 4A is an elevated cross-sectional view to
show a first embodiment of the present disclosure, wherein three
grooves are formed through stamping operation. FIG. 4B is an
elevated cross-sectional view to show a modified example in
accordance with a first embodiment of the present disclosure,
wherein three grooves are formed through cutting operation.
[0024] FIG. 5 is an illustration to show a golf club in accordance
with a second embodiment of the present disclosure, corresponding
to FIG. 3.
[0025] FIGS. 6A and 6B are elevated cross-sectional views. FIG. 6A
is an illustration to show a golf club in accordance with a second
embodiment of the present disclosure, corresponding to FIG. 4A.
FIG. 6B shows a face portion of a conventional golf club without
any grooves, corresponding to FIG. 4B.
[0026] FIG. 7 is a comparative table to show a result of durability
test with regarding to golf clubs according to embodiments of the
present disclosure, compared with a conventional golf club.
DETAILED DESCRIPTION
[0027] Embodiments according to the present disclosure are
hereinafter described in detail with reference to accompanying
drawings.
[0028] FIGS. 1A and 1B are overall views to show a golf club 1 in
accordance with a first embodiment of the present disclosure. FIG.
1B is a front view of the golf club 1. FIG. 1A is a left side view
of FIG. 1B. FIG. 2 is a cross-sectional view taken along section
lines A-A in FIG. 1B. FIG. 3 is a cross-sectional view taken along
section lines B-B in FIG. 2. FIGS. 4A and 4B are elevated
cross-sectional views in P portion of FIG. 2. FIG. 4A is an
elevated cross-sectional view to show a first embodiment of the
present disclosure, wherein three grooves are formed through
stamping operation. FIG. 4B is an elevated cross-sectional view to
show a modified example in accordance with a first embodiment of
the present disclosure, wherein three grooves are formed through
cutting operation.
[0029] Note that, a golf club 1 shown in FIGS. 1A to 4B is an iron
type golf club.
[0030] The gold club 1 includes: a face portion 12, being disposed
at a front face of the gold club 1 and having a striking face for
hitting a golf ball; a hosel portion 13, being a shaft connection
portion on a shaft side, and configured to attach a shaft 18; a
topline portion 14, being disposed at an upper section; a toe
portion 15, being disposed at a front section; a sole portion 16,
being disposed at a bottom section to be put on a ground; and a
heel portion 17, being disposed at a rear section. And, the shaft
18 is inserted and connected to the hosel portion 13 of the gold
club 1.
[0031] A body portion, including the hosel portion 13, the topline
portion 14, the toe portion 15, the sole portion 16 and the heel
portion 17, is formed through hot forging a low-carbon steel, such
as "S20C" or the like. The face portion 12 made of a rolled
material is welded with the body portion to be integrally fixed
therewith (refer to FIG. 2).
[0032] The material of the face portion 12 is a special steel where
a vanadium is added to the material "SAE8655", regarding the
detailed components and contents, including: carbon (C) 0.40-0.80
wt %, silicon (Si) less than or equal to 0.60 wt %, manganese (Mn)
0.60-1.50 wt %, phosphorus (P) less than or equal to 0.020 wt %,
sulfur (S) less than or equal to 0.025 wt %, chrome (Cr) 0.30-1.00
wt %, nickel (Ni) 0.30-0.80 wt %, molybdenum (Mo) 0.10-0.50 wt %,
vanadium (V) 0.05-0.40 wt %, and the rest iron (Fe) and inevitable
impurities (refer to Japanese Patent No. 4280565).
[0033] The face portion 12 is rolled along a direction heading from
the topline portion 14 to the sole portion 16 as denoted an arrow
19 (i.e., a rolling direction) in FIG. 1B, in a rolling operation.
A thickness of the face portion 12 is 2.06 mm. When a direction
heading from the toe portion 15 to the heel portion 17 (hereinafter
referred to as "toe-heel direction") is a longitudinal direction,
eleven score lines 122 are formed on a striking face 121 of the
face portion 12, and these eleven score lines 122 are evenly spaced
apart and parallel to each other along a direction intersecting
with the toe-heel direction.
[0034] A back surface 123 of the face portion 12 has at least one
groove 125 provided at a location lower than a center of gravity
124 (equal to a foot of a perpendicular taken from a center of
gravity of a golf club head to the striking face 121) on the
striking face 121 of the face portion 12. The groove 125 is
provided extending from a proximity of the toe portion 15 to a
proximity of the heel portion 17. As shown in FIG. 3, three grooves
125 are provided evenly spaced apart and parallel to each other
along the direction intersecting with the toe-heel direction. The
groove 125 has an arc-like groove 125A located at a proximity of
the toe portion 15 and formed extending upwardly along an arc of
the toe portion 15. This arc-like groove 125A causes a size of
so-called "sweet spot" to be expanded toward the toe portion 15.
FIG. 4A is an elevated cross-sectional view to show a first
embodiment of the present disclosure, wherein three grooves 125 are
formed through stamping operation. These three grooves 125 are
formed through stamping operation by a punch 21. The groove 125 is
formed in semi-arc-like shape in cross-section, and the groove 125
has 0.4 mm in depth and 0.5 mm in radius R. Two convex surfaces
127, 127 located between two grooves 125, 125 are formed slightly
lower than the back surface 123, so that the groove 125 has a shape
that is easily for performing stamping operation. FIG. 4B is an
elevated cross-sectional view to show a modified example in
accordance with a first embodiment of the present disclosure,
wherein the groove 125 is formed through cutting operation by an
end mill 22. The groove 125 is formed in semi-arc-like shape in
cross-section, and the groove 125 has 0.4 mm in depth and 0.5 mm in
radius R, as well as shown in FIG. 4A.
[0035] FIGS. 5 and 6A show a golf club in accordance with a second
embodiment of the present disclosure, wherein one groove 126 is
formed through cutting operation by the end mill 22 and is located
lower than the center of gravity 124 on the striking face 121 of
the face portion 12. The groove 126 is formed extending from a
proximity of the toe portion 15 to a proximity of the heel portion
17. The groove 126 has an arc-like groove 126A located at a
proximity of the toe portion 15 and formed extending upwardly (more
upwardly than as in FIG. 3) along an arc of the toe portion 15.
This arc-like groove 126A causes a size of so-called "sweet spot"
to be expanded toward the toe portion 15. As shown in FIG. 6A, the
groove 126 is formed as a wide groove having 3.0 mm in width and
0.2 mm in depth and 0.5 mm in radius R at both ends in
cross-section. For comparison, FIG. 6B shows a conventional face
portion 12 without any grooves, corresponding to FIG. 4B.
[0036] FIG. 7 is a comparative table to show a result of durability
test with regarding to golf clubs according to embodiments of the
present disclosure, compared with a conventional golf club. As
shown in "columns of FIG. 4A, FIG. 4B and FIG. 6A" of FIG. 7, the
grooves 125 or 126 formed in the back surface 123 of face portion
12 contribute to a higher coefficient of restitution (0.828) in
comparison to a coefficient of restitution (0.826) of a
conventional golf club without any grooves, thus allowing for an
increased amount of deflection (1.2% to 2.1% up) of the face
portion 12 upon impact with a golf ball during golf swing, thereby
permitting a golf ball to fly a longer distance.
[0037] In addition, the grooves 125 or 126 are formed along a
direction perpendicular to a rolling direction 19 of the face
portionl2, thus causing it hard to produce a crack. Specially, the
grooves 125 formed through stamping operation according to a first
embodiment of the present disclosure shown in FIG. 4A, will not cut
a metal structure extending along the rolling direction 19 of the
face portion 12. As shown in the result of durability test at the
head velocity of 40 m/s in FIG. 7, the grooves 125 or 126 formed
through stamping operation, therefore, allows for enhancing the
durability of the face portion 12 in comparison to another
embodiment of the present disclosure shown in FIGS. 4B and 6A,
wherein the grooves 125 or 126 are formed through cutting
operation.
[0038] Various embodiments of the present disclosure have been
described with reference to the accompanying drawings, however the
above-mentioned description and drawings are not to be construed as
limiting the disclosure. For example, the number of pieces of the
grooves 125 may be more than one, and is not to limit to three as
in the above-mentioned embodiment shown in FIGS. 4A and 4B. For
another example, the cross-sectional shape of the groove 125 may be
other shape such as trapezoid or the like, and is not to limit to a
semi-arc as in the above-mentioned embodiment shown in FIGS. 4A and
4B. For another example, the above-mentioned embodiments of the
present disclosure can be applied to not only the irons but also
pitching wedges as well as approach wedges. For another example,
the thickness of the face portion 12 is preferably 2.06 mm, and may
be less than or equal to 2.1 mm.
REFERENCE SIGNS LIST
[0039] 1 golf club
[0040] 12 face portion
[0041] 121 striking face
[0042] 122 score line
[0043] 123 back surface
[0044] 124 center of gravity
[0045] 125 groove
[0046] 125A arc-like groove
[0047] 126 groove
[0048] 126A arc-like groove
[0049] 127 convex surface
[0050] 13 hosel portion
[0051] 14 topline portion
[0052] 15 toe portion
[0053] 16 sole portion
[0054] 17 heel portion
[0055] 18 shaft
[0056] 19 rolling direction of face portion
[0057] 21 punch
[0058] 22 end mill
* * * * *