U.S. patent application number 15/805782 was filed with the patent office on 2018-03-01 for forged slotted iron golf club.
The applicant listed for this patent is c/o MIZUNO CORPORATION. Invention is credited to Kazuhiro Doi, Tetsuya Kanayama, David Llewellyn, Chris Voshall.
Application Number | 20180056151 15/805782 |
Document ID | / |
Family ID | 58053623 |
Filed Date | 2018-03-01 |
United States Patent
Application |
20180056151 |
Kind Code |
A1 |
Doi; Kazuhiro ; et
al. |
March 1, 2018 |
FORGED SLOTTED IRON GOLF CLUB
Abstract
An iron golf club head is disclosed. The iron golf club head can
include a hosel portion, a heel portion, a toe portion, a face
portion, and a sole portion all forged from a single piece of
steel. The iron golf club head can further include a slot cut in
the forged club behind the face portion between the heel portion
and the toe portion. The slot can have a sole opening and a cavity
opening, and a plug can be located in the sole opening.
Inventors: |
Doi; Kazuhiro; (Osaka,
JP) ; Kanayama; Tetsuya; (Osaka, JP) ;
Llewellyn; David; (Norcross, GA) ; Voshall;
Chris; (Norcross, GA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
c/o MIZUNO CORPORATION |
Osaka |
|
JP |
|
|
Family ID: |
58053623 |
Appl. No.: |
15/805782 |
Filed: |
November 7, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
14820908 |
Aug 7, 2015 |
|
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15805782 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A63B 2209/00 20130101;
A63B 60/02 20151001; A63B 2053/0491 20130101; A63B 60/52 20151001;
A63B 53/0475 20130101; A63B 53/047 20130101 |
International
Class: |
A63B 53/04 20060101
A63B053/04 |
Claims
1. A method for making an iron golf club head, comprising the steps
of: forging a hosel portion, a heel portion, a toe portion, a face
portion, and a sole portion, wherein the hosel portion, heel
portion, toe portion, face portion, and sole portion are all forged
from a single piece of steel; cutting a continuous slot behind the
face and extending between the heel portion and the toe portion
through a middle portion of the head in the heel to toe direction,
the slot having a sole opening and a cavity opening; and securing a
plug in the sole opening.
2. The method of claim 1, wherein cutting the continuous slot
behind the face creates a face thickness that is measured between
an outer surface thereof and the continuous slot, wherein the face
thickness in the middle portion is less than or equal to the face
thickness in the heel portion and the toe portion.
3. The method of claim 1, wherein the step of securing the plug in
the sole opening further comprises: providing the plug, wherein the
plug comprises a metal; welding the plug over the sole opening; and
sanding the sole portion of the iron golf club head to create a
substantially continuous sole surface.
4. The method of claim 3, wherein the metal is steel.
5. The method of claim 3, wherein the metal is tungsten.
6. The method of claim 1, wherein the step of securing the plug in
the sole opening further comprises: providing the plug, wherein the
plug comprises a plastic insert; and press-fitting the plug into
the sole opening.
7. The method of claim 1, wherein the weight of the plug is less
than about 10% of the weight of the entire iron golf club head.
8. The method of claim 1, further comprising the step of securing a
cavity plug in the cavity opening.
9. The method of claim 8, wherein the step of securing the cavity
plug in the cavity opening further comprises: providing the cavity
plug, wherein the cavity plug comprises a plastic insert; and
press-fitting the plug into the cavity opening.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a division of, and claims priority to,
co-pending U.S. patent application Ser. No. 14/820,908, filed 7
Aug. 2015, the contents of which is incorporated herein by
reference in its entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present invention relates to an iron golf club head and
an iron golf club, and more specifically to a forged iron golf club
head having a slot cut behind the face.
Description of the Background Art
[0003] There are many qualities of a golf club that a golfer uses
to assess its quality and performance. Two such attributes that are
relatively easy to evaluate for a player are the sound and feel of
the ball striking, and the flight distance of the ball.
[0004] It is generally accepted at the ultimate method of
production when it comes to feel is forging. By forging a golf
club, a manufacturer is able to ensure greater consistency from
piece to piece and an improved internal consistency of the club.
The forging process also avoids the issue of "pin holes" that exist
as an artifact of the alternative casting process. These pin holes
lead to less consistent vibrations, and this affects the feel of
the club.
[0005] A forged product will also have a longer grain structure in
the metal which will affect the overall duration of vibration. The
longer grain structure of a forged iron is known to produce more
consistent and desired vibrations and sounds that help provide
feedback to the golfer. These characteristics of forged clubs have
long been the reasons that the majority of experienced and well
accomplished golfers have leaned towards playing forged irons.
[0006] While the term "forging" has been used extensively in the
golf industry, its use has been associated with many different
degrees and arrangements of clubs. Typically, as long as a single
piece of the clubs is forged, many manufacturers will call the club
forged. This means that many clubs marketed as "forged" are only
partially created using a forging process. This limited use of
forging drastically limits many of the feel and consistency
benefits of the process.
[0007] The ideal club design for vibration and feel purposes would
be a single forged piece, with no cast elements attached thereto. A
single piece forging will have the most true vibrations and also
the most consistent vibrations because each additional piece which
is added (either through welding, brazing, or some other method of
adhesion) introduces another level of tolerances for
inconsistencies as well as additional vibration dampening caused by
non-continuous grains.
[0008] Along with feel, another goal in club design is to increase
the coefficient of restitution ("COR") of the club face. An iron
with a high COR will generate faster ball speeds. One of the keys
to increasing the COR is generally to increase the area of thinner
portions of the face.
[0009] A club with a thin face is traditionally difficult to
achieve when using the forging process. The limitations on the
forging process include requirements as to draft angles and minimum
thicknesses to avoid forging defects. These limitations have pushed
club manufacturers to compromise club feel for ease of
manufacturing. Some manufacturers have created combinations such as
having a forged hosel and face portion welded to a cast back
portion or having a forged club body and hosel welded to a maraging
steel face portion.
[0010] What is needed, therefore, is a club head that maintains a
high percentage of forged construction, while also having the high
COR that results from having a club face with thin areas. It is to
such a golf club that embodiments of the present invention are
primarily directed.
SUMMARY OF THE INVENTION
[0011] The present invention addresses the above issue, and
contemplates an iron golf club head that can provide an enhanced
club feel while maintaining a high COR.
[0012] In some embodiments, an iron golf club head can comprise a
hosel portion, a heel portion, a toe portion, a face portion, and a
sole portion forged from a single piece of steel. Embodiments
according to the present disclosure can include a slot disposed
behind the face portion between the heel portion and the toe
portion, with the slot having a sole opening and a cavity opening.
In some embodiments, a plug is located in the sole opening.
[0013] In some embodiments, the plug can be a piece of metal welded
over the sole opening to create a substantially continuous sole
surface. The plug can also be a plastic insert that is press-fit
into the sole opening. Embodiments according to the present
disclosure may be made such that the weight of the plug is less
than about 10% of the weight of the entire iron golf club head.
[0014] In some embodiments, the club head further includes a cavity
plug in the cavity opening. The cavity plug may be a plastic insert
that can be press-fit into the cavity opening.
[0015] Embodiments according to the present disclosure may also
relate to a method for making an iron golf club head. In some
embodiments, such a method can include forging a hosel portion, a
heel portion, a toe portion, a face portion, and a sole portion
from a single piece of steel. In some embodiments, the method may
include cutting a slot behind the face portion between the heel
portion and the toe portion, with the slot having a sole opening
and a cavity opening. A method according to the present disclosure
can include plugging the sole opening.
[0016] In some embodiments, the step of plugging the sole opening
may also include providing a plug made of a piece of metal, welding
the plug over the sole opening, and sanding the sole portion of the
iron golf club head to create a substantially continuous sole
surface.
[0017] In some embodiments, the step of plugging the sole opening
may include providing a plug made of plastic, and press-fitting the
plug into the sole opening.
[0018] In some embodiments, the method may include plugging the
cavity opening in addition to the sole opening. The step of
plugging the cavity opening may include providing a cavity plug
made of plastic, and press-fitting the plug into the cavity
opening.
[0019] The foregoing and other objects, features, aspects and
advantages of the present invention will become more apparent from
the following detailed description of the present invention when
taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a perspective view of an iron golf club according
to an embodiment of the present invention.
[0021] FIG. 2 is a perspective view of an iron golf club according
to an embodiment of the present invention that illustrates the slot
in dashed lines.
[0022] FIG. 3 is a cross-section of an iron golf club taken along a
line 3-3 shown in FIG. 1.
[0023] FIG. 4 is a cross-section of an iron golf club taken along a
line 3-3 shown in FIG. 1 according to an embodiment of the present
invention that includes a welded plug.
[0024] FIG. 5 is a cross-section of an iron golf club taken along a
line 3-3 shown in FIG. 1 according to an embodiment of the present
invention that includes plastic plugs in the slot.
DETAILED DESCRIPTION
[0025] Embodiments of the present invention relate generally to
golf clubs, and more particularly to forged iron golf clubs. In
some embodiments, a club according to the current disclosure may be
over 90% forged by weight. This design allows for more of the
benefits of forging, without the downsides associated with a
low-COR striking face. The resulting club has a high-COR,
comparable with or better than other commercially available
"forged" clubs, but also has an improved feel due to its increased
percentage of forged construction.
[0026] To simplify and clarify explanation, the invention is
described herein as a slotted iron golf club. One skilled in the
art will recognize, however, that the invention is not so
limited.
[0027] The materials described hereinafter as making up the various
elements of the present invention are intended to be illustrative
and not restrictive. Many suitable materials that would perform the
same or a similar function as the materials described herein are
intended to be embraced within the scope of the invention. Such
other materials not described herein can include, but are not
limited to, materials that are developed after the time of the
development of the invention.
[0028] As described above, a general problem with so-called
"forged" golf clubs is that they are only forged in some small
part, and thus can't fully reap the benefits of the long grain
associated with the forging process. The present invention
according to an embodiment is thus useful in that it can provide an
iron golf club head with improved feel, which possesses a high
COR.
[0029] Although the present invention has been described and
illustrated in detail, it is clearly understood that the same is by
way of illustration and example only and is not to be taken by way
of limitation, the scope of the present invention being interpreted
by the terms of the appended claims.
[0030] In some embodiments, as shown in FIGS. 1-3, an iron golf
club head 10 is provided with a hosel portion 12, a heel portion
14, a toe portion 16, a face portion 18, and a sole portion 20. To
provide the club with a higher-COR, a slot 22 is cut behind face
portion 18 and having a sole opening 24 and a cavity opening 26.
Slot 22 allows face portion 18 to have a larger thin area than a
club that has been made with only traditional forging.
[0031] As shown in FIG. 4, embodiments of an iron golf club head 40
according to the present disclosure may have plug 28 disposed in
the sole opening end of slot 22. Plug 28 may be a piece of steel
that is welded or otherwise secured into place in sole opening 24.
Once plug 28 is secured, sole portion 20 may be sanded and polished
so as to leave no protruding edges to cause undesired turf
interaction.
[0032] Plugs such as that depicted in FIG. 4 may be of several
different water resistant materials of suitable durability. In some
embodiments, other metals such as tungsten could be used to add
weight and move the center of gravity of the club towards the sole.
Other embodiments may use a lighter material such as an epoxy or a
metal such as aluminum. The selection of the density and volume of
material used may be made based on providing a desired center of
gravity for the club head.
[0033] As shown in FIG. 5, embodiments of an iron golf club head 50
may have plugs 30 and 32 made of a plastic or rubberized material.
Plugs 30 and 32 may be press fit into sole opening 24 and/or cavity
opening 26. In some embodiments, plugs 30 and 32 may be secured by
other reasonable means such as glues or epoxies.
[0034] Some embodiments in accordance with the present disclosure
may have a mix of metal welded and press-fit plugs. The plugs serve
to eliminate undesired turf interactions as well as to prevent
moisture or debris entering slot 22. If slot 22 has moisture or
debris in it, there may be corrosion or other adverse effects on
the club's performance or durability.
[0035] While several possible embodiments are disclosed above,
embodiments of the present invention are not so limited. For
instance, while several possible configurations have been disclosed
(e.g., embodiments with a single slot, or a slot with two plugs),
other suitable slot configurations and plugs could be selected
without departing from the spirit of embodiments of the invention.
In addition, the location and configuration used for various
features of embodiments of the present invention can be varied
according to a particular golf club that requires a slight
variation due to, for example, the size or construction of the golf
club, the user, or cost issues. Such changes are intended to be
embraced within the scope of the invention.
[0036] The specific configurations, choice of materials, and the
size and shape of various elements can be varied according to
particular design specifications or constraints requiring a device,
system, or method constructed according to the principles of the
invention. Such changes are intended to be embraced within the
scope of the invention. The presently disclosed embodiments,
therefore, are considered in all respects to be illustrative and
not restrictive. The scope of the invention is indicated by the
appended claims, rather than the foregoing description, and all
changes that come within the meaning and range of equivalents
thereof are intended to be embraced therein.
* * * * *