U.S. patent application number 14/669249 was filed with the patent office on 2015-10-01 for golf club head and golf club.
The applicant listed for this patent is Mizuno Corporation. Invention is credited to Kazuhiro Doi, Tsugunobu Sakamoto.
Application Number | 20150273287 14/669249 |
Document ID | / |
Family ID | 54188911 |
Filed Date | 2015-10-01 |
United States Patent
Application |
20150273287 |
Kind Code |
A1 |
Doi; Kazuhiro ; et
al. |
October 1, 2015 |
GOLF CLUB HEAD AND GOLF CLUB
Abstract
A main body portion including a face and a recess formed on a
back side of the face, an intermediate member being arranged in the
recess, including a first member and a second member, and having a
smaller specific gravity than the main body portion, and a high
specific gravity member being arranged on a side opposite to the
main body portion when viewed from the intermediate member and
having a higher specific gravity than the intermediate member are
provided.
Inventors: |
Doi; Kazuhiro; (Osaka,
JP) ; Sakamoto; Tsugunobu; (Osaka, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Mizuno Corporation |
Osaka |
|
JP |
|
|
Family ID: |
54188911 |
Appl. No.: |
14/669249 |
Filed: |
March 26, 2015 |
Current U.S.
Class: |
473/350 |
Current CPC
Class: |
A63B 2053/0491 20130101;
A63B 53/047 20130101; A63B 53/0408 20200801; A63B 2209/00
20130101 |
International
Class: |
A63B 53/04 20060101
A63B053/04 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 28, 2014 |
JP |
2014068479 |
Claims
1. A golf club head comprising: a main body portion including a
face and a recess formed on a back side of said face; an
intermediate member being arranged in said recess, including a
first member and a second member, and having a lower specific
gravity than said main body portion; and a high specific gravity
member being arranged on a side opposite to said main body portion
when viewed from said intermediate member, and having a higher
specific gravity than said intermediate member.
2. The golf club head according to claim 1, wherein said first
member has a lower specific gravity than said main body portion,
and said second member has a lower specific gravity than said first
member.
3. The golf club head according to claim 2, wherein said first
member is constituted of a metal material, and said second member
is constituted of a resin material.
4. The golf club head according to claim 1, wherein said recess is
formed in a region overlapping with at least a part of a hitting
position of said face when viewed from said face.
5. The golf club head according to claim 1, wherein in said
intermediate member, said first member is joined to said main body
portion, and said second member is joined to said high specific
gravity member.
6. The golf club head according to claim 1, wherein said main body
portion includes a heel portion located at an end portion on a side
of a shaft and a toe portion located at an end portion on an
opposite side of said heel portion with respect to said face, and
in a direction from said heel portion toward said toe portion, a
thickness of a central portion of said first member is relatively
larger than a thickness of a portion other than said central
portion in said first member.
7. The golf club head according to claim 6, wherein said central
portion of said first member is provided so as to overlap with at
least a portion of a hitting position of said face.
8. The golf club head according to claim 1, wherein an adhesive is
used to join said first member and said second member and to join
said intermediate member and said high specific gravity member.
9. The golf club head according to claim 1, wherein said main body
portion, said intermediate member, and said high specific gravity
member are integrally formed without a hollow portion.
10. A golf club comprising the golf club head according to claim 1.
Description
[0001] This nonprovisional application is based on, and claims
priority to Japanese Patent Application No. 2014-068479 filed on
Mar. 28, 2014 with the Japan Patent Office, the entire contents of
which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a golf club head and a golf
club.
[0004] 2. Description of the Background Art
[0005] In a golf club head, various structures have been employed
with respect to a face portion having a ball-hitting portion.
[0006] For example, a face portion of a golf club head has been
conventionally formed to have a multilayer structure in which a
plurality of materials are layered. Japanese Patent Laying-Open No.
2007-160702 discloses a golf club head using a multilayer metal
clad plate having a three-layer structure as a face member for the
purpose of moderating a shock of an impact while utilizing a
repulsive force of a surface layer.
SUMMARY OF THE INVENTION
[0007] However, it is difficult to effectively achieve improvement
in a ball-hitting feeling with a conventional golf club head
including the golf club head disclosed in Japanese Patent
Laying-Open No. 2007-160702.
[0008] Generally, a golfer cannot have a good ball-hitting feeling
when a ball-hitting sound is loud and is less likely to be
attenuated. In order to improve the ball-hitting feeling, it is
conceivable to provide a thick face portion to suppress a flexure
of the face portion at the time of hitting a ball. However, in this
case, a disadvantage may arise in that an inertia moment of a golf
club head is lowered, so that a rotation of the golf club head is
like to occur at the time of hitting a ball and thereby causes a
flying distance to be shorter.
[0009] The present invention was made to solve the problem
described above. A main object of the present invention is to
provide a golf club head and a golf club capable of suppressing
lowering of the inertia moment while effectively achieving
improvement in the ball-hitting feeling.
[0010] 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
[0011] FIG. 1 is a side view for illustrating a golf club head and
a golf club according to the present embodiment.
[0012] FIG. 2 is a cross-sectional view taken along the II-II line
in FIG. 1.
[0013] FIG. 3 is a cross-sectional view taken along the III-III
line in FIG. 1.
[0014] FIG. 4 is a cross-sectional view for illustrating a modified
example of the golf club head according to the present
embodiment.
[0015] FIG. 5 is a cross-sectional view for illustrating another
modified example of the golf club head according to the present
embodiment.
[0016] FIG. 6 is a cross-sectional view for illustrating yet
another modified example of the golf club head according to the
present embodiment.
DETAILED DESCRIPTION
[0017] In the following, an embodiment of the present invention
will be described with reference to the drawings. It should be
noted that the same or corresponding portions in the following
drawings have the same reference numerals allotted, and description
thereof will not be repeated.
[0018] Referring to FIGS. 1 to 3, a golf club and a golf club head
1 according to the present embodiment will be described. The golf
club according to the present embodiment has a golf club head 1
connected to one end of a shaft 20. A grip portion is formed at the
other end located on a side opposite to the one end of shaft 20.
Golf club head 1 according to the present embodiment includes a
main body portion 2, an intermediate member 4, and a high specific
gravity member 5.
[0019] Main body portion 2 includes a face 2A and a recess 3 formed
on a back side of face 2A. Face 2A constitutes a ball-hitting face.
Main body portion 2 has a hitting position HP on face 2A. Hitting
position HP is defined as being within a 10 mm radius circle with a
center located on a score line center in a toe-heel direction and
at a location of 15 mm above a leading edge (an end portion located
on a side of a sole portion 6 of face 2A) along the face.
[0020] A plurality of score lines, which are not illustrated, may
be formed on face 2A. A material constituting main body portion 2
may be any metal material, and it is for example mild carbon steel
(S25C as defined in the JIS standard).
[0021] In main body portion 2, at least a part of recess 3 is
preferably formed in a region overlapping with hitting position HP
of face 2A when viewed from a side of face 2A. A planar shape of
recess 3 when recess 3 is viewed in a planar view from the back
side of face 2A may be in any shape. However, it preferably has an
oblong shape in which a width in a direction from a side of a heel
portion 1h to a toe portion 1t is larger than a width in a
direction from a side of sole portion 6 to a side of a top edge
portion 7. Moreover, preferably, a width of recess 3 in a direction
from the side of sole portion 6 to the side of edge portion 7 is
provided so that it is larger in a region near a central portion 1c
than a region located on a side of heel portion 1h and toe portion
1t.
[0022] An inner circumferential surface of recess 3 formed along an
outer shape of main body 2 on a back side of face 2A is constituted
of a bottom surface 3A and a side surface 3B extending in a
direction of intersecting bottom surface 3A. A structure of recess
3 can be optionally selected as long as intermediate member 4 can
be fixed within recess 3 without a gap. For example, an angle
formed between bottom surface 3A and side surface 3B is greater
than or equal to 90 degrees, and is preferably an obtuse angle.
[0023] Bottom surface 3A of recess 3 is opposite to face 2A across
main body portion 2, and is provided as one flat surface. The
thickness of main body portion 2 in the region having recess 3 is,
for example, greater than or equal to 2.6 mm and less than or equal
to 3.4 mm. Side surface 3B may be formed such that a plurality of
surfaces intersecting with bottom surface 3A intersect with each
other.
[0024] Intermediate member 4 is arranged within recess 3. A planar
shape of intermediate member 4 when recess 3 is viewed in a plan
view from a back side of face 3A can be any shape. However,
preferably, it has an oblong shape in which a length in a direction
from the side of heel portion 1h to toe portion 1t is greater than
a length in a direction from the side of sole portion 6 to the side
of top edge portion 7.
[0025] Intermediate member 4 includes a first member 4a and a
second member 4b. First member 4a and second member 4b are
configured to be layered in a direction perpendicular to face 2A.
In other words, while first member 4a is directly connected to
bottom surface 3A of recess 3, second member 4b is not directly
connected to bottom surface 3A of recess 3.
[0026] A material constituting first member 4a may be any metal
material having a lower specific gravity than main body portion 2
and high specific gravity member 5 which will be described later.
The material constituting first member 4a is, for example, pure
titanium (Ti), titanium alloy, aluminum alloy, magnesium alloy, or
the like.
[0027] A material constituting second member 4b may be any material
having a lower specific gravity than main body portion 2 and high
specific gravity member 5 which will be described later, and
preferably is a material satisfying the relationship of a specific
gravity of second member 4b<a specific gravity of first member
4a. The material constituting second member 4b is, for example, ABS
(Acrylonitrile Butadiene
[0028] Styrene) resin or epoxy resin. A surface of second member 4b
may be covered with a plated layer (not illustrated). A material
constituting the plated layer is, for example, nickel chromium
(NiCr). The material constituting the plated layer may be any
material. However, when a material having a high specific gravity
is used for the plated layer, it is preferable that the film
thickness of the plated layer is sufficiently smaller than a width
of second member 4b in a direction perpendicular to face 2A.
Moreover, as long as the relationship of a specific gravity
described above is satisfied, aluminum alloy or magnesium alloy can
be used as second member 4b.
[0029] A specific gravity of first member 4a which is in proximity
to face 2A and connected to main body portion 2 is preferably
higher than a specific gravity of second member 4b connected to
high specific gravity member 5. This is because while it is desired
on one hand to arrange a metal material directly on face 2A to
suppress flexure of the face (main body portion 2), it is also
desired on the other hand to reduce a weight of intermediate member
4 as a whole. Therefore, it is preferable that second member 4b
employs a material such as resin having a lower specific gravity
than first member 4a made of a metal material.
[0030] Referring to FIG. 2, it is not necessary to render a
thickness of first member 4a in a direction perpendicular to face
2A to be uniform in a direction from the side of sole portion 6 to
the side of top edge portion 7. The above-described thickness of
first member 4a is preferably larger on the side of sole portion 6
than on the side of top edge portion 7.
[0031] In such a manner, in intermediate member 4 constituted as a
composite member, a center of gravity of first member 4a can be set
lower as compared to the case where first member 4a having a higher
specific gravity than second member 4b is configured as a
rectangular parallelepiped. Therefore, a position of a center of
gravity of golf club head 1 can be lowered.
[0032] Referring to FIG. 3, it is preferable that the thickness of
first member 4a in a direction perpendicular to face 2A is not
uniform in a direction from the side of heel portion 1h to the side
of toe portion 1t through a central portion 1c. Specifically, the
above-described thickness of intermediate member 4 at central
portion 1c is preferably greater than the thickness at heel portion
1h or toe portion 1t.
[0033] In other words, first member 4a is thicker near central
portion 1c than on the side of heel portion 1h and the side of toe
portion 1t. Therefore, the amount of displacement of central
portion 1c which is most likely to be flexed at the time of hitting
a ball can be reduced. Accordingly, the ball-hitting sound can be
lowered and a good hitting feeling can be obtained.
[0034] In this case, the thickness in a direction perpendicular to
face 2A of second member 4b and in the top sole direction is
preferably large in the range included in hitting position HP.
[0035] Since either first member 4a and second member 4b are
constituted of a material having a lower specific gravity than main
body portion 2 or high specific gravity member 5 as described
above, intermediate member 4 as a whole has a lower specific
gravity than main body portion 2 or high specific gravity member 5.
The thickness of intermediate member 4 in a direction perpendicular
to face 2A at the time when intermediate member 4 is fixed to
recess 3 is, for example, greater than or equal to 2.5 mm and less
than or equal to 10.5 mm.
[0036] High specific gravity member 5 is arranged on a side
opposite to main body portion 2 when viewed from intermediate
member 4. High specific gravity member 5 is joined to at least a
part of second member 4b in intermediate member 4. In other words,
high specific gravity member 5 is formed at a position most apart
in a backward direction from the side of face 2A in golf club head
1. High specific gravity member 5 may be formed so as to cover an
entire surface on a side opposite to the side of face 2A in
intermediate member 4, but may also be formed on a region located
on the side of sole portion 6 in the above-described surface of
intermediate member 4. High specific gravity member 5 is provided
so as to overlap with at least a part of recess 3 when golf club
head 1 is viewed from a side opposite to face 2A.
[0037] High specific gravity member 5 may have any shape, and it
has a structure in which a plate-like member is bent. High specific
gravity member 5 may be provided with a face located on a side of
face 2A and connected to intermediate member 4 and a face located
on the opposite side and risen, and the faces are provided, for
example, in parallel with each other.
[0038] High specific gravity member 5 has a higher specific gravity
than intermediate member 4. The material constituting high specific
gravity member 5 is a material having a higher specific gravity
than intermediate member 4, and it is for example stainless steel
(SUS), more preferably a stainless steel strip (SUS304CSP). The
thickness of high specific gravity member 5 is, for example,
greater than or equal to 0.3 mm and less than or equal to 0.5 mm.
It should be noted that the specific gravity of high specific
gravity member 5 may be equal to the specific gravity of main body
portion 2. As long as the specific gravity of main body portion 2
and the specific gravity of high specific gravity member 5 are
substantially equal, the specific gravity of high specific gravity
member 5 may be slightly lower or higher than the specific gravity
of main body portion 2.
[0039] Main body portion 2, intermediate member 4, and high
specific gravity member 5 are formed integrally without a hollow
portion. In other words, an inner portion of golf club head 1 (each
inner portion of main body portion 2, intermediate member 4, and
high specific gravity member 5) does not have a hollow portion and
has a dense structure.
[0040] A connection between main body portion 2 and intermediate
member 4 and a connection between intermediate member 4 and high
specific gravity member 5 may be provided in any manner as long as
main body portion 2, intermediate member 4, and high specific
gravity member 5 as one golf club head 1 are not disconnected even
at the time of hitting a ball. Main body portion 2 and intermediate
member 4 are preferably connected by, for example, press-fitting.
Specifically, it is preferable that first member 4a having a planar
shape which is larger than a dimension of recess 3 of main body
portion 2 and analogous to a planar shape of recess 3 is
press-fitted into recess 3 to connect main body portion 2 and first
member 4a. At this time, first member 4a is arranged in recess 3 in
a state where main body portion 2 is heated and thermally expanded,
and thereafter main body portion 2 is cooled and thermally
contracted, so that first member 4a can be press-fitted into recess
3 of main body portion 2. In this manner, a joining strength
between main body portion 2 and intermediate member 4 can be
enhanced.
[0041] First member 4a and second member 4b may be joined by means
of a double-faced tape. Moreover, second member 4b and high
specific gravity member 5 may be joined by means of a double-faced
tape. At this time, a joining interface between first member 4a and
second member 4b is closer to face 2A than a joining surface
between second member 4b and high specific gravity member 5 and has
a large amount of displacement, a double-faced tape for use in
joining first member 4a and second member 4b is required to have a
higher strength than a double-faced tape for use in joining second
member 4b and high specific gravity member 5. Therefore, the
double-faced tape for use in joining, for example, first member 4a
and second member 4b may be thicker than the thickness of the
double-faced tape for use in joining second member 4b and high
specific gravity member 5.
[0042] Next, the effects of golf club head 1 according to the
present embodiment will be described. Golf club head 1 includes
main body portion 2 having face 2A and recess 3 formed on a back
side of face 2A, intermediate member 4 arranged in recess 3,
including first member 4a and second member 4b, and having a lower
specific gravity than main body portion 2, and high specific
gravity member 5 arranged on a side opposite to main body portion 2
when viewed from intermediate member 4 and having a higher specific
gravity than intermediate member 4.
[0043] In this manner, the thickness of the ball-hitting portion of
golf club head 1 configured by connecting main body portion 2,
intermediate member 4, and high specific gravity member 5 can be
set larger. Accordingly, a ball-hitting sound can be lowered by
reducing a flexure of the head caused at the time of hitting a
ball, so that a ball-hitting feeling of golf club head 1 can be
improved.
[0044] At this time, since intermediate member 4 is constituted of
a material having a lower specific gravity than main body portion
2, an increase in a mass of golf club head 1 due to thickening of
golf club head 1 can be suppressed. Consequently, lowering of the
inertia moment in golf club head 1 is suppressed.
[0045] Moreover, with respect to intermediate member 4, high
specific gravity member 5 constituted of a material having a high
specific gravity is provided at a position most apart from face 2A,
so that the depth of the center of gravity of golf club head 1 (a
distance from the center of gravity of golf club head 1 to face 2A)
can be set greater. Consequently, the inertia moment can be set
greater than the conventional golf club head not including
intermediate member 4. Here, the inertia moment of golf club head 1
represents the inertia moment having an axis on a line extending in
a vertical direction through the center of gravity of golf club
head 1 and an axis on a line extending in a horizontal direction
through the center of gravity of golf club head 1. Accordingly,
when a ball is hit at a part deviated from a sweet spot of the golf
club head, the deviation from the sweet spot causes golf club head
1 to rotate about the center of gravity, but since the inertia
moment of golf club head 1 can be improved, the rotation of golf
club head 1 can be suppressed. Consequently, a high stability as to
the ball-hitting direction and a flying distance can be
achieved.
[0046] Moreover, since intermediate member 4 is constituted of
first member 4a and second member 4b, intermediate member 4 having
various characteristics can be obtained by combining materials. For
example, also in the case where a material of first member 4a being
close to face 2A and connected to main body portion 2 is limited by
the method of connection, constituting second member 4b with a
material having a lower specific gravity than first member 4a can
provide a lower specific gravity as a whole in intermediate member
4.
[0047] Preferably, first member 4a is constituted of a metal
material, and second member 4b is constituted of a resin material.
Therefore, since a specific gravity lower than main body portion 2
or high specific gravity member 5 can be provided, the inertia
moment can be set greater.
[0048] Moreover, recess 3 is formed in the region overlapping with
hitting position HP of face 2A when viewed from the side of face
2A, so that the region overlapping with hitting position HP having
a great flexure at the time of hitting a ball can be thickened, and
the ball-hitting feeling can be improved more effectively.
[0049] Moreover, in intermediate member 4, first member 4a is
joined to main body portion 2, and second member 4b is joined to
high specific gravity member 5. In other words, first member 4a and
second member 4b are preferably configured to be layered in a
direction perpendicular to face 2A. Therefore, the variation in the
ball-hitting characteristic in face 2A can be suppressed.
[0050] Moreover, in the direction from heel portion 1h to toe
portion 1t, the thickness of a central portion 4ac of first member
4a is provided so as to be relatively larger than the thickness of
a portion other than central portion 4ac in first member 4a (a
portion on a side of heel portion 1h or on a side of toe portion
1t), and central portion 4ac of first member 4a is provided so as
to overlap with hitting position HP of face 2A. Accordingly, a
flexure of hitting position HP (central portion 1c) having a large
flexure in the direction from heel portion 1h to toe portion 1t at
the time of hitting a ball can be suppressed effectively, so that
the ball-hitting sound can be reduced.
[0051] An adhesive may be used to join first member 4a and second
member 4b and to join intermediate member 4 and high specific
gravity member 5.
[0052] Moreover, main body portion 2, intermediate member 4, and
high specific gravity member 5 are layered continuously without a
hollow portion. Therefore, as compared to a golf club head having a
hollow portion, a flexure of a golf club head can be suppressed
effectively. Consequently, a ball-hitting feeling can be
effectively improved with golf club head 1.
[0053] Since the golf club according to the present embodiment
includes golf club head 1, the inertia moment can be suppressed
while effectively achieving the improvement in the ball-hitting
feeling.
[0054] In intermediate member 4 according to the present
embodiment, first member 4a is joined to main body portion 2, and
second member 4b is joined to high specific gravity member 5, but
is not limited to this embodiment.
[0055] Referring to FIG. 4, for example, second member 4b may be
joined to main body portion 2, and first member 4a may be joined to
high specific gravity member 5. In other words, golf club head 1
may have a configuration in which second member 4b, first member
4a, and high specific gravity member 5 are layered from the side of
face 2A in this order in the direction perpendicular to face 2A
without a hollow portion. In this case, intermediate member 4
constituted of a material having a lower specific gravity than main
body portion 2 is connected to main body portion 2, so that the
inertia moment of golf club head 1 can be set greater, and the
depth of the center of gravity can also be set greater.
[0056] Moreover, referring to FIG. 5, in golf club head 1, recess 3
is formed so as to extend in main body portion 2 from the side of
sole portion 6 to the side of top edge portion 7, and intermediate
member 4 may be provided in recess 3 from the side of sole portion
6. At this time, main body portion 2 includes a face side main body
portion 21 located between face 2A and recess 2 and a back side
main body 22 located on a back side of recess 3 when viewed from
face 2A.
[0057] In this case, in view of the depth of the center of gravity
and the inertia moment, it is preferable that the thickness of face
side main body portion 21 is provided so as to be smaller than the
thickness of back side main body portion 22. Such golf club head 1
has a four-layer structure in which face side main body portion 21,
first member 4a, second member 4b, and back side main body portion
22 are layered from the side of face 2A in the direction
perpendicular to face 2A without a hollow portion. Therefore, as
with golf club head 1 described above, the relationship of a
specific gravity of second member 4b<a specific gravity of first
member 4a is satisfied, and the specific gravity of face side main
body portion 21 and the specific gravity of back side main body
portion 22 can be substantially equal. Consequently, the
ball-hitting feeling of golf club head 1 can be improved, and the
inertia moment of golf club head 1 can be set greater.
[0058] Further, referring to FIG. 6, in golf club head 1, a hole
portion 8 which is a closed space being close with respect to main
body portion 2 is formed in place of recess 3, and intermediate
member 4 may be provided in hole portion 8. Also in this case, in
view of the depth of the center of gravity and the inertia moment,
it is preferable that the thickness of face side main body portion
21 located between face 2A and recess 3 is provided so as to be
smaller than the thickness of back side main body portion 22
located on a back side of recess 3 when viewed from the side of
face 2A. Such golf club head 1 has a four-layer structure in which
face side main body portion 21, first member 4a, second member 4b,
and back side main body portion 22 are layered from the side of
face 2A in the direction perpendicular to face 2A without a hollow
portion. Therefore, as with golf club head 1 described above, the
relationship of a specific gravity of second member 4b<a
specific gravity of first member 4a is satisfied, and the specific
gravity of face side main body portion 21 and the specific gravity
of main body portion 22 can be substantially equal. Consequently,
the ball-hitting feeling of golf club head 1 can be improved, and
the inertia moment of golf club head 1 can be greater. It should be
noted that, in golf club head 1 shown in FIG. 6, the position at
which intermediate member 4 is provided with respect to sole
portion 6 is more apart toward the side of top edge portion 7 as
compared to golf club head 1 shown in FIG. 5, so that the volume of
the region occupied by main body portion 2 is larger near sole
portion 6 and smaller near top edge portion 7. Therefore, the
position of the center of gravity of golf club head 1 shown in FIG.
6 can be arranged lower than the position of the center of gravity
of golf club head 1 toward the side of sole portion 6.
[0059] Golf club head 1 shown in FIG. 6 may be formed, for example,
by forming a hole in main body portion 2 from the side surface of
the side of heel portion 1h or the side of toe portion 1t,
inserting intermediate member 4 into the hole, and thereafter
closing the opening of the hole by means of another member.
[0060] 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.
* * * * *