U.S. patent application number 12/496130 was filed with the patent office on 2010-06-10 for golf club head.
This patent application is currently assigned to BRIDGESTONE SPORTS CO., LTD.. Invention is credited to Wataru Ban.
Application Number | 20100144461 12/496130 |
Document ID | / |
Family ID | 42231716 |
Filed Date | 2010-06-10 |
United States Patent
Application |
20100144461 |
Kind Code |
A1 |
Ban; Wataru |
June 10, 2010 |
GOLF CLUB HEAD
Abstract
A golf club head of this invention includes a head body, a
weight member attached to the head body, and a fixing unit to fix
the weight member at one of a plurality of attachment positions of
the head body. The plurality of attachment positions are located on
a plane. The plane includes the center-of-gravity position of the
head body without the weight member attached thereto and the axis
of a shaft to be attached to the golf club head.
Inventors: |
Ban; Wataru; (Saitama,
JP) |
Correspondence
Address: |
SUGHRUE MION, PLLC
2100 PENNSYLVANIA AVENUE, N.W., SUITE 800
WASHINGTON
DC
20037
US
|
Assignee: |
BRIDGESTONE SPORTS CO.,
LTD.
Tokyo
JP
|
Family ID: |
42231716 |
Appl. No.: |
12/496130 |
Filed: |
July 1, 2009 |
Current U.S.
Class: |
473/338 |
Current CPC
Class: |
A63B 60/02 20151001;
A63B 53/0466 20130101; A63B 53/08 20130101; A63B 2053/0491
20130101; A63B 53/04 20130101; A63B 53/0433 20200801 |
Class at
Publication: |
473/338 |
International
Class: |
A63B 53/06 20060101
A63B053/06 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 9, 2008 |
JP |
2008-313695 |
Claims
1. A golf club head comprising: a head body; a weight member
attached to said head body; and fixing means for fixing said weight
member at any one of a plurality of attachment positions of said
head body, wherein the plurality of attachment positions are
located on a plane, and the plane includes a center-of-gravity
position of said head body without said weight member attached
thereto and an axis of a shaft to be attached to the golf club
head.
2. The head according to claim 1, wherein said fixing means
comprises: a plurality of first screw portions which are provided
in a sole portion of said head body and define the plurality of
attachment positions; and a second screw portion which is provided
in said weight member and threadably engages with one of said
plurality of first screw portions.
3. The head according to claim 1, further comprising a rail portion
which is formed along a straight line included in the plane in said
sole portion of said body and defines the plurality of attachment
positions, wherein said fixing means fixes said weight member at a
given position on said rail portion.
4. The head according to claim 3, wherein said rail portion
comprises: a groove open at a lower part thereof, which is formed
along the straight line and forms an accommodation space to
accommodate said weight member; a partitioned chamber closed at an
upper part thereof, which is formed along the straight line in an
upper portion of said groove; a partitioning portion which is
provided between said groove and said partitioned chamber and
vertically partitions the space into said groove and said
partitioned chamber; and a slit which is formed along the straight
line in said partitioned chamber and makes the space in said groove
communicate with said partitioned chamber, and said fixing means
comprises: a slide member which is accommodated in said partitioned
chamber such that said slide member can move along the straight
line, and connected to said weight member through said slit; and
screw portions which are respectively provided in said slide member
and said weight member, and threadably engage with each other.
5. The head according to claim 1, wherein a change amount of
center-of-gravity depth of the golf club head caused by a
difference between the attachment positions used to fix said weight
member is not less than 3 mm.
6. The head according to claim 1, wherein said weight member
comprises a plurality of weight members having different
weights.
7. The head according to claim 1, further comprising a resin member
which is inserted between said head body and said weight member at
the attachment position.
8. The head according to claim 7, wherein said resin member is
integrally provided in said weight member.
9. The head according to claim 1, wherein said weight member is
fixed to said sole portion of said head body, said sole portion
includes a recess formed in the attachment position of said weight
member, and a depth of said recess is set such that a lowest
portion of said weight member fixed to said head body is positioned
above a lowest portion of said sole portion.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a golf club head.
[0003] 2. Description of the Related Art
[0004] There have been proposed golf club heads in which golfers
can change the position of a weight member attached to the golf
club head in accordance with their preference. Japanese Patent
Laid-Open Nos. 2001-137400, 2006-102235, and 2007-222257 disclose
putter heads in which the position of the weight member can be
changed. Japanese Utility Model Laid-Open No. 7-15067, Japanese
Patent Laid-Open No. 11-9742, and Japanese Utility Model
Registration No. 3127234 disclose wood type golf club heads in
which the position of the weight member can be changed.
[0005] When the position of the weight member is changed, the
center-of-gravity position of the golf club head changes. When the
center-of-gravity position changes, the characteristics of the golf
club head change and, for example, the height or lateral
directionality of flight of a hit ball, playability, ball
catchability, and the like change. The catchability means golfer's
feeling at the impact. A Golfer feels good catchability if the
golfer obtains solid ball striking and easily rotates the golf club
head through impact. Golfers can change the position of the weight
member in accordance with their preference.
[0006] When the position of the weight member is changed, however,
a plurality of characteristics of the golf club head may
simultaneously change. Some golfers may want to keep the ball
catchability unchanged but change other characteristics of the golf
club head.
SUMMARY OF THE INVENTION
[0007] It is an object of the present invention to provide a golf
club head in which the position of a weight member can be changed,
a change in ball catchability is suppressed as much as possible but
the other characteristics of the golf club head can be changed by
changing the position of the weight member.
[0008] According to the present invention, there is provided a golf
club head comprising a head body, a weight member attached to the
head body, and fixing means for fixing the weight member at any one
of a plurality of attachment positions of the head body, wherein
the plurality of attachment positions are located on a plane, and
the plane includes a center-of-gravity position of the head body
without the weight member attached thereto and an axis of a shaft
to be attached to the golf club head.
[0009] Further features of the present invention will become
apparent from the following description of exemplary embodiments
with reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a perspective view of a golf club head A according
to one embodiment of the present invention;
[0011] FIG. 2 is a sectional view of a sole portion 13 taken along
a line X-X in FIG. 1;
[0012] FIG. 3 is a view for explaining a center-of-gravity angle
.theta.;
[0013] FIG. 4 is a sectional view showing the arrangement of
attachment portions 131a to 131d according to the second embodiment
of the present invention;
[0014] FIG. 5 is a sectional view showing the arrangement of
attachment portions 131a to 131d and a weight member 20 according
to the third embodiment of the present invention;
[0015] FIG. 6A is a sectional view of a sole portion 13 in the
fourth embodiment; and
[0016] FIG. 6B is a sectional view taken along a line X-X in FIG.
6A.
DESCRIPTION OF THE EMBODIMENTS
[0017] Preferred embodiments of the present invention will now be
described in detail in accordance with the accompanying
drawings.
First Embodiment
[0018] FIG. 1 is a perspective view of a golf club head A, and
particularly of a sole portion 13 according to one embodiment of
the present invention.
[0019] The golf club head A includes a head body 10 and a weight
member 20. The head body 10 is a hollow body, and its
circumferential wall constitutes a face portion 11 forming a golf
ball hitting surface, a crown portion 12 forming the top surface of
the golf club head A, the sole portion 13 forming the bottom
surface of the golf club head A, and a side portion 14 forming the
toe-side, heel-side, and back-side side surfaces of the golf club
head A. A hosel portion 15 to which a shaft is to be attached is
also provided in the head body 10.
[0020] Although the golf club head A is a golf club head for a
driver, the present invention is applicable to wood type golf club
heads including a fairway wood and the like other than a driver,
utility type (hybrid type) golf club heads, and other hollow golf
club heads. The head body 10 is a hollow body in this embodiment,
but it may be solid.
[0021] The head body 10 can be assembled by joining a plurality of
parts. For example, the face portion 11 and the other part can be
formed as different members and joined to form the head body 10.
Also, the face portion 11, sole portion 13, and the other part can
be formed as different members and joined to form the head body 10.
The head body 10 can be made from, for example, a metal material
including a titanium metal material and stainless steel. The head
body 10 can be made from different materials. For example, it can
be formed from a metal material and a carbon fiber material. As a
carbon fiber material, a carbon fiber reinforced resin (CFRP) is
available.
[0022] A plurality of attachment portions 131a to 131d, which
define the attachment positions of the weight member 20, are formed
in the sole portion 13. Although four attachment portions 131a to
131d are provided in this embodiment, the number of the attachment
portions is not limited to four. The user of the golf club head A
can attach the weight member 20 to any one of the attachment
portions 131a to 131d. FIG. 2 is a sectional view of the sole
portion 13 taken along a line X-X in FIG. 1.
[0023] Each of the attachment portions 131a to 131d forms a tube
having a female screw hole SC1. The weight member 20 has an axial
male screw portion SC2. The weight member 20 can be fixed to the
head body 10 by threadably engaging the female screw hole SC1 and
male screw portion SC2 to each other.
[0024] A washer 30 is a resin member inserted between the weight
member 20 and the sole portion 13. The washer 30 serves to prevent
loose threadable engagement between the female screw hole SC1 and
male screw portion SC2, thereby preventing the weight member 20
fixed once from falling easily. The washer 30 may be integrally
provided in the weight member 20. For example, the washer 30 may be
fixed to the weight member 20 in advance. Also, the surface of the
weight member 20 may be covered with a resin material.
[0025] As shown in FIG. 2, of the attachment portions 131a to 131d,
the female screw holes SC1 to which the weight member 20 is not
attached can be closed by attaching caps 40. With this arrangement,
it is possible to prevent dust and the like from entering the head
body 10 through the female screw holes SC1. The cap 40 is made
from, for example, a resin material, and detachably fitted in the
female screw hole SC1. In order to prevent dust and the like from
entering the head body 10 through the female screw holes SC1,
instead of using the caps 40, the female screw holes SC1 may be
closed at their upper ends.
[0026] The cap 40 is formed to have the same shape as the weight
member 20. The material of the cap 40 is selected such that its
weight substantially gives no influence on a change in
center-of-gravity position. The cap 40 may be formed to screw in
the female screw hole SC1.
[0027] The weight member 20 can be made from, for example, a metal
material. As such a metal material, for example, tungsten, a
tungsten alloy, aluminum, an aluminum alloy, magnesium, and a
magnesium alloy are available. The weight member 20 may be made by,
for example, mixing a metal powder with a viscoelastic material. In
this case, the vibration dampening effect of the golf club head A
at impact can improve. As such a viscoelastic material, for
example, NBR (acrylonitrile-butadiene rubber) is available.
[0028] The positions of the attachment portions 131a to 131d will
be described with reference to FIGS. 1 and 3.
[0029] FIG. 3 is a view for explaining a center-of-gravity angle
.theta., which shows the golf club head A seen from the sole
portion 13 side while the shaft of the golf club using the golf
club head A is kept rotatable about the axis of the shaft and
horizontally supported In FIG. 3, an arrow Dh represents the
horizontal direction and an arrow Dv represents the vertical
direction.
[0030] In FIGS. 1 and 3, a center-of-gravity position CG represents
the center-of-gravity position of the head body 10 without the
weight member 20 attached thereto. A plane S is a virtual plane
that includes the center-of-gravity position CG of the head body 10
and an axis L1 of a shaft (not shown) to be mounted to the golf
club head A. Since the shaft is mounted to the hosel portion 15,
the axis L1 is substantially the same as the axis of the hosel
portion 15. The attachment portions 131a to 131d are located on the
plane S, and particularly on a straight line L0 included in the
plane S in this embodiment.
[0031] The effect obtained by arranging the attachment portions
131a to 131d on the plane S will be described next. When the weight
member 20 is fixed to any one of the attachment portions 131a to
131d, the center-of-gravity position and center-of-gravity depth of
the golf club head A change accordingly. In this embodiment, the
center-of-gravity depth is the length of a perpendicular from the
center-of-gravity position of the golf club head to the face
portion. When the face portion 11 forms not a flat surface but an
arcuate surface, a virtual plane touching the face center is used
as the reference.
[0032] For example, when the weight member 20 is attached to the
attachment portion 131a, the center-of-gravity position of the golf
club head A moves toward the heel side from the center-of-gravity
position CG of the head body 10. Accordingly, the center-of-gravity
length of the golf club head A becomes relatively short, and the
playability of the golf club head A improves. When the
center-of-gravity position of the golf club head A is located
relatively on the heel side, it becomes relatively easy to hook a
ball. However, since the center-of-gravity angle hardly changes, as
described below, it can be avoided to excessively catch the ball.
Therefore, when the weight member 20 is attached to the attachment
portion 131a, a club that is good in playability and easily
produces a draw ball flight can be obtained.
[0033] When the weight member 20 is attached to the attachment
portion 131d, the center-of-gravity position of the golf club head
A moves toward the toe side from the center-of-gravity position CG
of the head body 10. Accordingly, the center-of-gravity length of
the golf club head A becomes relatively long and, in regard of the
playability of the golf club head A, the golfer easily feels the
weight of the head and the movement of golfer's fingers rarely
influences the behavior of the golf club head A. In addition, when
the center-of-gravity position of the golf club head A is located
relatively on the toe side, it becomes relatively easy to slice a
ball. However, since the center-of-gravity angle hardly changes, as
described below, it can be avoided to excessively deteriorate ball
catchability. Therefore, when the weight member 20 is attached to
the attachment portion 131d, the golf club head A becomes to show a
behavior insensitive to golfer's operation, and a club that easily
produces a fade ball flight independent of golfer's skill can be
obtained.
[0034] As described above, in this embodiment, the characteristics
of the golf club head A can be changed by selecting the attachment
portions 131a to 131d used to fix the weight member 20.
[0035] Since the attachment portions 131a to 131d are located on
the plane S, the center-of-gravity angle .theta. hardly changes
regardless of the attachment portions 131a to 131d used to attach
the weight member 20, as will be understood from FIG. 2. The
center-of-gravity angle .theta. is an angle formed by the face
portion 11 and the vertical plane (plane S in FIG. 1) that passes
the axis L1. The center-of-gravity angle .theta. mainly influences
ball catchability at impact. When the center-of-gravity angle
.theta. is larger, a ball is caught relatively more easily. When
the center-of-gravity angle .theta. is smaller, a ball is caught
relatively less easily.
[0036] As described above, in this embodiment, a change in ball
catchability at impact can be suppressed as much as possible but
other characteristics of the golf club head A can be changed by
changing the attachment position of the weight member 20.
[0037] Although the one weight member 20 is used in this
embodiment, one of a plurality of the weight members 20 having
different weights may be selectively fixed to the head body 10.
With this arrangement, it becomes possible to widen the selection
range of center-of-gravity position and center-of-gravity depth of
the golf club head A and to increase their choices as well. In this
case, the two or more weight members 20 may simultaneously be fixed
to the head body 10.
[0038] The change amount of center-of-gravity depth of the golf
club head A caused by the difference between the attachment
portions 131a to 131d used to fix the weight member 20, for
example, the difference in center-of-gravity depth between a case
in which the weight member 20 is attached to the attachment portion
131a and a case in which the weight member 20 is attached to the
attachment portion 131d, is preferably 3 mm or more. When the
difference in center-of-gravity depth is 3 mm or more, a golfer can
more clearly feel the change in characteristics of the golf club
head caused by the change in center-of-gravity position.
Second Embodiment
[0039] FIG. 4 is a sectional view showing another arrangement
example of attachment portions 131a to 131d, which corresponds to
the sectional view of a sole portion 13 taken along the line X-X in
FIG. 1. The same components as in the golf club head A of the
above-described first embodiment are denoted by the same reference
numerals below, and a description thereof will not be repeated.
Only components different from those of the golf club head A will
be described.
[0040] In this embodiment, recesses 132a to 132d to accommodate a
weight member 20 are provided in the attachment portions 131a to
131d, respectively. The depth of each of the recesses 132a to 132d
is set such that the lowest portion of the weight member 20 fixed
to a head body 10 is positioned above the lowest portion of the
sole portion 13.
[0041] With this arrangement, as shown in FIG. 4, the weight member
20 does not project from the sole portion 13. Accordingly, it is
possible to prevent the weight member 20 from catching the ground
upon hitting a ball.
Third Embodiment
[0042] FIG. 5 is a sectional view showing another arrangement
example of attachment portions 131a to 131d and weight member 20,
which corresponds to the sectional view of a sole portion 13 taken
along the line X-X in FIG. 1. The same components as in the golf
club head A of the above-described first embodiment are denoted by
the same reference numerals below, and a description thereof will
not be repeated. Only components different from those of the golf
club head A will be described.
[0043] In this embodiment, axial male screw portions SC3 are
provided in the respective attachment portions 131a to 131d, and a
female screw hole SC4 which threadably engages with the male screw
portion SC3 is provided in a weight member 20. Each of the
attachment portions 131a to 131d has an internal space to
accommodate the weight member 20, thereby preventing the weight
member 20 from projecting from the sole portion 13, as in the
above-described second embodiment.
[0044] In this manner, the screw portion on the sole portion 13
side and that on the weight member 20 side are a male screw and
female screw, respectively, and vice versa.
Fourth Embodiment
[0045] In the above-described first to third embodiments, the
weight member 20 can be fixed at a plurality of positions spaced
apart from each other. However, a weight member 20 may be fixable
at a given position on a straight line included in a plane S. With
this arrangement, it is possible to more finely adjust the
center-of-gravity position and center-of-gravity depth of the golf
club head.
[0046] FIG. 6A is a sectional view of a sole portion 13 in the
fourth embodiment, and corresponds to the sectional view of the
sole portion 13 taken along the line X-X in FIG. 1. FIG. 6B is a
sectional view taken along a line X-X in FIG. 6A, and shows a state
in which the weight member 20 is detached. The same components as
in the golf club head A of the above-described first embodiment are
denoted by the same reference numerals below, and a description
thereof will not be repeated. Only components different from those
of the golf club head A will be described.
[0047] A rail portion 50 extending along a straight line L0 (see
FIG. 1) included in the plane S is formed in the sole portion 13.
As described below, the rail portion 50 guides the movement of the
weight member 20. The rail portion 50 includes a groove 51 formed
by recessing the sole portion 13 and open at its lower part, and a
partitioned chamber 52 formed in the upper portion of the groove
51. Both the groove 51 and partitioned chamber 52 are formed along
the above-described straight line L0.
[0048] The groove 51 has a pair of side walls 13a and a pair of
partitioning portions 13b formed by bending the side walls 13a. The
partitioning portions 13b are located between the groove 51 and
partitioned chamber 52, thereby vertically partitioning them. The
pair of the partitioning portions 13b are spaced apart from each
other to form a slit 53. The groove 51 accommodates the weight
member 20. The depth of the groove 51 is set such that the lowest
portion of the weight member 20 fixed to the head body 10 is
positioned above the lowest portion of the sole portion 13. With
this arrangement, the weight member 20 does not project from the
sole portion 13, and therefore it is possible to prevent the weight
member 20 from catching the ground upon hitting a ball.
[0049] The partitioned chamber 52 is formed by joining the lower
ends of a lid member 54 having a U-shaped cross section to the
partitioning portions 13b. The upper part of the partitioned
chamber 52 is closed by the lid member 54.
[0050] The partitioned chamber 52 accommodates a slide member 55.
The slide member 55 is sized such that it cannot rotate in the
partitioned chamber 52 and, for example, has a square shape when
viewed from the above. An axial male screw portion SC5 that passes
the slit 53 is integrally connected to the slide member 55. A
female screw hole SC6 which threadably engages with the male screw
portion SC5 is formed in the weight member 20. The width of the
weight member 20 is larger than that of the slit 53 in the
widthwise direction.
[0051] The end portion of the rail portion 50 on the heel side is
closed by a wall portion 16, which is formed by bending a part of
the head body 10, and a part of the lid member 54. The toe-side end
portion of the rail portion 50 is open, and a closing member 141 is
mounted thereto to close it. Upon assembling the head body 10,
after the slide member 55 is inserted into the partitioned chamber
52 from the toe-side end portion of the rail portion 50, the
closing member 141 is secured to the head body 10 to close the
toe-side end portion. For example, the closing member 141 may be
made from an elastic body such as rubber so that it is detachable
from the head body 10. In this case, it becomes possible to
exchange the slide member 55.
[0052] In this embodiment with the above-described components, when
the male screw portion SC5 threadably engages with the female screw
hole SC6, the slide member 55 and weight member 20 sandwich the
partitioning portions 13b, thereby fixing the weight member 20 to
the head body 10. A washer 30 inserted between the partitioning
portions 13b and weight member 20 prevents the loose threadable
engagement between the male screw portion SC5 and female screw hole
SC6.
[0053] When changing the position of the weight member 20, the
threadable engagement between the male screw portion SC5 and female
screw hole SC6 is loosened, and the slide member 55 and the weight
member 20 are moved. Since these members are guided by the rail
portion 50 during movement, their positions can be easily changed.
By threadably engaging the male screw portion SC5 with the female
screw hole SC6 at a desired position, the weight member 20 can be
fixed.
[0054] As described above, in this embodiment, the weight member 20
can be fixed at a given position on the straight line L0, and
therefore it is possible to more finely adjust the
center-of-gravity position and center-of-gravity depth of the golf
club head. Note that in this embodiment, the center-of-gravity
position of the head body 10 is defined as a center-of-gravity
position CG of the head body 10 without the weight member 20 and
slide member 55. Also, in this embodiment, since the weight member
20 can be completely detached from the slide member 55, one of a
plurality of the weight members 20 having different weights may be
selectively fixed to the head body 10.
[0055] In this embodiment, since the rail portion 50 is enclosed by
the closing member 141, wall portion 16, and lid member 54, it is
possible to prevent dust and the like from entering the head body
10 through the rail portion 50.
[0056] Note that the structure of the rail portion 50 is not
limited to that shown in FIGS. 6A and 6B, but any structure can be
used as long as the weight member 20 can be moved and fixed at a
given position.
[0057] While the present invention has been described with
reference to exemplary embodiments, it is to be understood that the
invention is not limited to the disclosed exemplary embodiments.
The scope of the following claims is to be accorded the broadest
interpretation so as to encompass all such modifications and
equivalent structures and functions.
[0058] This application claims the benefit of Japanese Patent
Application No. 2008-313695, filed Dec. 9, 2008, which is hereby
incorporated by reference herein in its entirety.
* * * * *