U.S. patent application number 14/471651 was filed with the patent office on 2015-03-05 for golf club head.
The applicant listed for this patent is Dunlop Sports Co. Ltd.. Invention is credited to Michael J. KLINE, Yuki MOTOKAWA.
Application Number | 20150065265 14/471651 |
Document ID | / |
Family ID | 52584007 |
Filed Date | 2015-03-05 |
United States Patent
Application |
20150065265 |
Kind Code |
A1 |
MOTOKAWA; Yuki ; et
al. |
March 5, 2015 |
GOLF CLUB HEAD
Abstract
A golf club head comprises a head main body having a hollow
therein and a weight member having a specific gravity more than
that of the head main body. The head main body has a face portion
for hitting a ball and a sole portion continuous from the face
portion to form a bottom surface of the club head. The weight
member is disposed in the hollow and extends in the toe-heel
direction. In a vertical cross section of the club head including
the sweet spot, the weight member is arranged without contacting
with the face portion and the sole portion.
Inventors: |
MOTOKAWA; Yuki; (Kobe-shi,
JP) ; KLINE; Michael J.; (Huntington Beach,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Dunlop Sports Co. Ltd. |
Kobe-shi |
|
JP |
|
|
Family ID: |
52584007 |
Appl. No.: |
14/471651 |
Filed: |
August 28, 2014 |
Current U.S.
Class: |
473/335 |
Current CPC
Class: |
A63B 53/04 20130101;
A63B 53/0408 20200801; A63B 60/00 20151001; A63B 53/0433 20200801;
A63B 60/52 20151001; A63B 53/0466 20130101; A63B 2053/0491
20130101; A63B 60/02 20151001 |
Class at
Publication: |
473/335 |
International
Class: |
A63B 53/06 20060101
A63B053/06 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 29, 2013 |
JP |
2013-178397 |
Claims
1. A golf club head comprising a head main body having a hollow
therein, the head main body comprising a face portion and a sole
portion extending from the face portion and defining a bottom
surface of the club head, and a weight member disposed in the
hollow, the weight member extending in a toe-heel direction of the
head across a vertical plane including the sweet spot of the head
and being substantially parallel with the front-back direction of
the head such that, in the vertical plane, the weight member does
not contact the face portion and the sole portion.
2. The golf club head according to claim 1, wherein in the vertical
plane, the weight member is disposed in a corner portion between
the face portion and the sole portion.
3. The golf club head according to claim 1, wherein in the vertical
plane, a centroid of a cross section of the weight member is
positioned on a face portion side of the center of gravity of the
head.
4. The golf club head according to claim 1, wherein in the vertical
plane, a centroid of a cross section of the weight member is
positioned on a sole portion side of the center of gravity of the
head.
5. The golf club head according to claim 1, wherein in the vertical
plane, an entire cross section of the weight member is positioned
on a sole portion side of the center of gravity of the head and on
a face portion side of the center of gravity of the head.
6. The golf club head according to claim 1, wherein the weight
member is spaced apart from the sole portion continuously in the
toe-heel direction between both end portions of the weight
member.
7. The golf club head according to claim 1, wherein a toe-side
portion and a heel-side portion of the weight member are fixed to
the head main body.
8. The golf club head according to claim 7, wherein the head main
body comprises a crown portion being continuous from the face
portion and defining a top surface of the club head, and a side
portion extending between the crown portion and the sole portion,
and the weight member comprises a toe-side end face fixed to a
toe-side part of the side portion, and a heel-side end face fixed
to a heel-side part of the side portion.
9. The golf club head according to claim 7, wherein the weight
member comprises a toe-side end fixed to a toe-side part of the
sole portion, and a heel-side end fixed to a heel-side part of the
sole portion.
10. The golf club head according to claim 1, wherein the area of
the cross section of the weight member is increased toward its
center in the toe-heel direction from its toe-side and from its
heel-side.
11. The golf club head according to claim 1, wherein the weight
member is fixed to the head main body by the use of a screw.
12. The golf club head according to claim 1, which comprises an
adjusting mechanism for changing the position of the weight member
in one of the front-back direction, up-down direction and toe-heel
direction of the head.
13. The golf club head according to claim 1, which comprises an
adjusting mechanism for changing the position of the weight member
in two of the front-back direction, up-down direction and toe-heel
direction of the head.
14. The golf club head according to claim 1, wherein The weight
member is welded to the head main body.
15. The golf club head according to claim 1, wherein the weight
member and the head main body are integrally formed by casting.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a hollow golf club head
with a weight member therein, more particularly to an attaching
structure for the weight member capable of increasing the design
freedom of weight distribution of the head without deteriorating
the rebound performance of the head.
[0002] U.S. Pat. No. 8,328,661 discloses a hollow golf club head
comprising a cup-shaped face member and a head main body united
therewith, wherein a tongue-shaped weight part extending in the
toe-heel direction is cast into the head main body or welded or
fixed mechanically to the head main body, and
the weight part extends upwards from the sole portion and forward
into the backside cavity of the face member. Therefore, such weight
part can shift the center of gravity of the head toward the club
face and also toward the sole portion.
[0003] In such club head, the bending rigidity of the sole portion
is increased by the weight part extending in the toe-heel direction
and united with the sole portion. As a result, the head main body
when hitting a ball becomes difficult to elastically deform in the
sole portion. Thus, the club head experiences decreased rebound
performance.
SUMMARY OF THE INVENTION
[0004] According to an aspect of the present disclosures, a golf
club head is disclosed in which the design freedom of weight
distribution of the head may be increased without deteriorating the
rebound performance of the head.
[0005] According to the present disclosure, a golf club head may
comprise
[0006] a head main body having a hollow therein, the head main body
comprising a face portion for hitting a ball, and a sole portion
being continuous from the face portion and defining a bottom
surface of the club head, and
[0007] a weight member disposed in the hollow, the weight member
extending in the toe-heel direction of the head across a vertical
plane including the sweet spot of the head and being parallel with
the front-back direction of the head such that, in the vertical
plane, the weight member does not contact with the face portion and
the sole portion.
[0008] The golf club head according to the present invention may
have the following features (1)-(14):
(1) in the vertical plane, the weight member may be disposed in a
corner portion between the face portion and the sole portion; (2)
in the vertical plane, the centroid of a cross section of the
weight member may be positioned on the face portion side of the
center of gravity of the head; (3) in the vertical plane, the
centroid of a cross section of the weight member may be positioned
on the sole portion side of the center of gravity of the head; (4)
in the vertical plane, the entirety of a cross section of the
weight member may be positioned on the sole portion side of and on
the face portion side of the center of gravity of the head; (5) the
weight member may be spaced apart from the sole portion
continuously in the toe-heel direction between both end portions of
the weight member; (6) a toe-side portion and a heel-side portion
of the weight member may be fixed to the head main body; (7) the
head main body may comprise a crown portion being continuous from
the face portion and defining a top surface of the club head, and a
side portion extending between the crown portion and the sole
portion, and
[0009] the weight member may comprise a toe-side end face fixed to
a toe-side part of the side portion, and a heel-side end face fixed
to a heel-side part of the side portion;
(8) the weight member may comprise a toe-side end fixed to a
toe-side part of the sole portion, and a heel-side end fixed to a
heel-side part of the sole portion; (9) the weight member may be
welded to the head main body; (10) the weight member may be fixed
to the head main body by the use of a screw; (11) the weight member
and the head main body may be integrally formed by casting; (12)
the area of the cross section of the weight member may increase
toward its center in the toe-heel direction from its toe-side and
from its heel-side; (13) the golf club head may comprise an
adjusting mechanism for changing the position of the weight member
in one of the front-back direction, up-down direction and toe-heel
direction of the head; (14) the golf club head may comprise
adjusting mechanisms for changing the position of the weight member
in two of the front-back direction, up-down direction and toe-heel
direction of the head.
[0010] Therefore, when a ball is hit at the sweet spot for example,
the face portion and the sole portion may deflect flexibly. As a
result, good rebound performance may be achieved.
[0011] In this application including the description and claims,
dimensions, positions, directions and the like relating to the club
head refer to those under a standard state of the club head unless
otherwise noted.
[0012] Here, the standard state of the club head is such that the
club head is set on a horizontal plane HP so that the axis of the
club shaft (not shown) is inclined at the specified lie angle alpha
while keeping the axis on a vertical plane, and the face forms the
specified loft angle with respect to the horizontal plane HP.
Incidentally, in the case of the club head alone, the center line
CL of the shaft inserting hole can be used instead of the axis of
the club shaft.
[0013] "Front-back direction" is a direction parallel with a
straight line N projected on the horizontal plane HP, wherein the
straight line N is drawn normally to the face 2a passing through
the center G of gravity of the club head.
[0014] "Toe-heel direction" is a direction parallel with the
horizontal plane HP and perpendicular to the front-back
direction.
[0015] "Sweet spot SS" is the point of intersection between the
face 2a and the straight line N drawn normally to the face 2a
passing the center of gravity G of the head.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a perspective view of a golf club head according
to the present disclosure.
[0017] FIG. 2 is a cross sectional view of the golf club head shown
in FIG. 1 taken along the vertical plane including the sweet spot
and extending parallel with the front-back direction of the
head.
[0018] FIG. 3 is a perspective view of an aft member constituting
the head main body.
[0019] FIG. 4 is a front view of the aft member shown in FIG.
3.
[0020] FIG. 5 is an exploded perspective view of an aft member of a
head main body in another embodiment of the present disclosure.
[0021] FIG. 6 is a cross sectional view of the aft member shown in
FIG. 5.
[0022] FIG. 7 is a cross sectional view of an aft member of a head
main body in a still another embodiment of the present
disclosure.
[0023] FIG. 8 is a cross sectional view of a club head as a
comparative example used in the comparative test descried
herein.
[0024] FIG. 9 is a schematic perspective view of a lower part of a
head main body in another embodiment of the present disclosure.
[0025] FIG. 10 is a cross sectional view taken along line A-A of
FIG. 9.
[0026] FIG. 11 is a schematic perspective view of a lower part of a
head main body in another embodiment of the present disclosure.
[0027] FIG. 12 is a cross sectional view taken along line A-A of
FIG. 11.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] Embodiments of present disclosure will now be described in
detail in conjunction with accompanying drawings.
[0029] Throughout all of the embodiments, the same members or
portions are denoted by the same numbers or letters.
[0030] The club head 1 may comprise a face portion 2, a crown
portion 3, a sole portion 4 and a side portion 5 so as to define an
internal hollow (i).
[0031] The face portion 2 has a club face 2a for hitting a
ball.
[0032] The crown portion 3 is continuous from the face portion 2
and forms a top surface of the club head.
[0033] The sole portion 4 is continuous from the face portion 2 and
forms a bottom surface of the club head.
[0034] The side portion 5 extends between the crown portion 3 and
the sole portion 4.
[0035] The side portion 5 is connected to the face portion 2 on the
toe-side and on the heel-side.
[0036] A hosel portion 6 is formed in a heel-side of the crown
portion 3. The hosel portion 6 is tubular and provided with a shaft
inserting hole 6a to be fixed to a golf club shaft (not shown).
[0037] In this embodiment, the club head 1 is for a wood-type
club.
[0038] The term "wood-type" is meant for at least a driver (#1
wood), brassie (#2 wood), spoon (#3 wood), baffy (#4 wood) and
cleek (#5 wood). In addition, club heads having similar shapes to
those wood-type club heads are included even if the number or name
of the club is different from the above.
[0039] The club head 1 may be constructed for a utility club in
another embodiment of the present disclosure.
[0040] The club head 1 may comprise a head main body 10 and a
weight member 11.
[0041] In this embodiment, the head main body 10 is a shell
structure surrounding the hollow (i) and includes the face portion
2, the crown portion 3, the sole portion 4, the side portion 5 and
the hosel portion 6.
The head main body 10 may be made of one or more kinds of metal
materials, for example, stainless, maraging steel, titanium alloy,
magnesium alloy, aluminum alloy and the like. However, it is also
possible that the head main body 10 may be partially or wholly
formed by one or more kinds of fiber reinforced resins.
[0042] The head main body 10 in this example is composed of a fore
member 10a and an aft member 10b.
[0043] The fore member 10a includes the face portion 2. In this
embodiment, as shown in FIG. 2, the fore member 10a includes the
entirety of the face portion 2 and a turnback 13 extending
backwardly from the peripheral edge of the face portion 2.
The fore member 10a may be cup-shaped. The fore member 10a may have
a cavity opened to the back of the club head. The fore member 10a
may have a rear edge 01 defined by the rear edge of the turnback
13.
[0044] The turnback 13 may form a fore part of the crown portion 3,
a fore part of the sole portion 4, a toe-side fore part of the side
portion 5, and a heel-side fore part of the side portion 5.
[0045] As show in FIG. 3, the aft member 10b may constitute a part
of the club head rearward of the fore member 10a.
[0046] In this embodiment, the aft member 10b may form an aft part
of the crown portion 3, an aft part of the sole portion 4, and an
aft part of the side portion 5. The aft member 10b is cup-shaped.
The aft member 10b has a cavity opened to the front of the club
head. The aft member 10b has a front edge 02 defined by the edges
of the aft parts of the portions 3, 4 and 5. In this embodiment,
the aft member 10b includes the hosel portion 6.
The aft member 10b is, however, not limited to such
arrangement.
[0047] As shown in FIG. 2, the rear edge 01 of the fore member 10a
and the front edge 02 of the aft member 10b may be butted with each
other and fixed, for example, by welding.
[0048] Such configuration of the fore member 10a and that of the
aft member 10b is merely an example. The configuration is not
limited to this example.
[0049] The weight member 11 may be disposed in the hollow (i). The
material for the weight member 11 can be arbitrarily selected
according to the material(s) of the head main body 10. The material
is not limited to specific ones, but metal materials, e.g.
stainless steel, maraging steel, titanium alloy, copper alloy,
tungsten alloy and the like can be suitably used.
[0050] In this embodiment, the weight member 11 may be made of a
material having a specific gravity more than that of the head main
body 10.
[0051] In another embodiment of the present disclosure, the weight
member 11 and the head main body 10 may be made of an identical
material.
Thus, the weight member 11 and the head main body 10 may have the
same specific gravity. In this case, the weight member 11 and the
head main body 10 may be formed integrally by casting.
[0052] As shown in FIG. 3, the weight member 11 may extend in the
toe-heel direction of the head.
[0053] It is not always necessary that the weight member 11
continuously extends over the entire range between the toe-side
extreme end and the heel-side extreme end of the hollow (i).
[0054] In this embodiment, the weight member 11 may be formed in
the shape of a rod that is long in the toe-heel direction as a
preferred configuration therefor.
[0055] As shown in FIG. 2, in the vertical cross section of the
club head including the sweet spot SS, the weight member 11 may be
arranged without contacting the face portion 2 and the sole portion
4. Therefore, as is clear from FIG. 2,
a space may be formed between the weight member 11 and the face
portion 2 arranged in the front-back direction, and a space may be
formed between the weight member 11 and the sole portion 4 arranged
in the up-down direction. These spaces are set such that, even when
the head main body 10 is deformed by hitting a ball, the noncontact
state of the weight member 11 can be maintained, namely, a certain
degree of space is retained. For that purpose, the spaces in the
nondeformed state of the head main body 10 are preferably set to be
not less than 3 mm.
[0056] In this embodiment, the weight member 11 may be disposed in
the hollow (i) without contacting the crown portion 3 and the side
portion 5.
In the vertical cross section of the club head, the weight member
11 preferably does not contact with the head main body 10 and it
may be arranged independently as if it floats in the hollow
(i).
[0057] When a ball is hit at the sweet spot SS of the club face 2a,
in the vertical cross section of the club head, the face portion 2
and sole portion 4 can therefore deflect without being hindered by
the weight member 11. In this embodiment, further, the crown
portion 3 and the side portion 5 can flexibly deflect without being
hindered by the weight member 11. Accordingly, the head main body
10 is wholly and effectively deflected when hitting a ball, and the
club head 1 can exert good rebound performance. Therefore, the club
head 1 can provide a long flying distance.
[0058] In the vertical cross section of the club head shown in FIG.
2, the weight member 11 is, for example, disposed so as to approach
a corner portion side formed by the face portion 2 and the sole
portion 4.
In this embodiment, the weight member 11 includes a part extending
over the edge 01 of the fore member 10a of the head main body 10
toward the club face. Preferably, the centroid (g) of a cross
section of the weight member 11 is positioned on the face portion 2
side of and on the sole portion 4 side of the center G of gravity
of the head. The entirety of the cross section of the weight member
11 is preferably positioned on the sole portion 4 side of the
center G of gravity of the head. The entirety of the cross section
of the weight member 11 is preferably positioned on the face
portion 2 side of the center G of gravity of the head. Such club
heads 1 may result in the center G of gravity of the head being
positioned lower, and closer to the club face 2a, therefore,
ballistic courses (less amount of spin) preferred by, for example,
advanced-level golfers can be achieved.
[0059] As shown in FIG. 4, the weight member 11 may be fixed to the
head main body 10 so as to be spaced apart from the inner surface
4i of the sole portion 4 continuously in the toe-heel direction in
substance.
In this embodiment, a toe-side and a heel-the side of the weight
member 11 are fixed to the head main body 10. In this embodiment,
further improved rebound performance can be exerted because the
weight member 11 is spaced apart from the head main body 10 not
only in the vertical cross section of the club head shown in FIG. 2
but also over a wide range in the toe-heel direction.
[0060] The weight member 11 comprises a bottom surface 15 facing
toward the sole portion 4 and a top surface 16 facing toward the
crown portion 3.
In the front view under the standard state, for example, the top
surface 16 may extend straight along the toe-heel direction in
substance. As a matter of course, the top surface 16 may be
inclined, and may be provided with a concave portion or a convex
portion. With respect to the shape of the back surface and the like
of the weight member 11, various configurations may be employed.
For example, the bottom surface 15 can include a curved surface 17
swelling toward the sole portion 5. Thereby, a cross section of the
weight member 11 in this embodiment (i.e. a cross section parallel
with the vertical cross section of the club head shown in FIG. 2)
increases to a central portion (sweet spot SS) side from the
toe-side junction position and heel-side junction position with the
head main body 10. Such weight member 11 can provide the center G
of gravity of the head which is further lowered.
[0061] The weight member 11 in this embodiment extends in the
toe-heel direction of the head to have a toe-side end 11a and a
heel-side end 11b.
The toe-side end 11a of the weight member 11 may be fixed to the
inner surface 5t of a toe-side part of the side portion 5. The
heel-side end 11b of the weight member 11 may be fixed to the inner
surface 5h of a heel-side part of the side portion 5. Excepting the
ends 11a and 11b, the weight member 11 preferably does not contact
with the head main body 10.
[0062] Incidentally, the boundary between the sole portion 4 and
the side portion 5 can be defined as lying at a height h of 4 mm
from the horizontal plane HP in the standard state as shown in FIG.
2 and FIG. 4.
[0063] In the embodiment shown in FIG. 4, each of the ends 11a and
11b of the weight member 11 may be fixed by welding. Accordingly, a
further strong junction of the weight member 11 and the head main
body 10 may be provided, and the club head 1 with excellent
durability may be obtained.
[0064] FIG. 5 and FIG. 6 show another embodiment of the present
disclosure.
[0065] In this embodiment, the method for attaching the weight
member 11 differs from that in the embodiment shown in FIG. 1 to
FIG. 4.
The weight member 11 may be fixed to the aft member 10b of the head
main body 10 by screws 22. In a toe-side part and a heel-side part
of the side portion 5 of the aft member 10b, a toe-side attaching
portion 20 and a heel-side attaching portion 21 for attaching the
weight member 11, respectively, may be provided.
[0066] The toe-side attaching portion 20 may be provided with a
groove 24 into which the toe-side end 11a of the weight member 11
can be inserted from the front side, and a hole 23 for inserting
the screw 22 into the weight member 11.
The hole 23 penetrates in the toe-heel direction through the
toe-side attaching portion 20.
[0067] The heel-side attaching portion 21 may be provided with a
groove 25 into which the heel-side end 11b of the weight member 11
can be inserted from the front side, and a hole 26 for inserting
the screw 22 into the weight member 11.
The hole 26 penetrates in the toe-heel direction through the
heel-side attaching portion 21.
[0068] The toe-side end 11a and the heel-side end 11b of the weight
member 11 may be provided with screw holes 27 and 28,
respectively.
The weight member 11 may be inserted in the grooves 24 and 25 of
the attaching portions 20 and 21 from the front side. Thereby, the
weight member 11 is temporary supported by the aft member 10b of
the head main body 10. Next, the screws 22 may be inserted through
the holes 23 and 26 and fixed to the screw holes 27 and 28 of the
weight member 11. FIG. 6 shows the fixed weight member 11.
[0069] In order to distribute more mass to the toe-side and
heel-side of the club head 1, a material having a specific gravity
more than that of the head main body 10 may be used for the screws
22. Thereby, it is possible to provide the club head 1 an increased
moment of inertia.
[0070] FIG. 7 shows still another embodiment of the present
disclosure.
[0071] In this embodiment, the method for attaching the weight
member 11 differs from those in the embodiments shown in FIG. 1 to
FIG. 6.
The weight member 11 may be fixed to the sole portion 4 of the head
main body 10 by screws. The sole portion 4 of the aft member 10b
may be provided with a toe-side attaching portion 31 and a
heel-side attaching portion 32 for attaching the weight member
11.
[0072] The toe-side attaching portion 31 may be formed as a convex
portion projecting into the hollow (i) formed by making a dent
locally in the club head's outer surface 40. The convex portion may
support the toe-side end 11a of the weight member 11 from the
underside.
The heel-side attaching portion 32 may be formed as a convex
portion projecting into the hollow (i) formed by making a dent
locally in the club head's outer surface 40. The convex portion may
support the heel-side end 11b of the weight member 11 from the
underside. Thereby, the weight member 11 may be supported by the
toe-side attaching portion 31 and the heel-side attaching portion
32, and the weight member 11 does not contact with the inner
surface of the sole portion 4 between them.
[0073] The toe-side attaching portion 31 and the heel-side
attaching portion 32 may be provided with through holes 33 and 36,
respectively.
The weight member 11 may be provided with screw holes 34 and 37 so
as to continue to the holes 33 and 36. The screws 35 and 38 may
penetrate through the holes 33 and 36, respectively, from the outer
surface side of the sole portion 4 and be fixed to the screw holes
34 and 37.
[0074] In this embodiment, although the weight member 11 is fixed
to the sole portion 4, the weight member 11 is spaced apart from
the head main body 10 over a wide range including the
above-mentioned vertical cross section A of the club head,
therefore, the same function as in the above-mentioned embodiments
can be expected.
[0075] Preferably, in the front view of the club head, the length w
measured in the toe-heel direction, of a region where the weight
member 11 is spaced apart from the head main body 10 is not less
than 35%, preferably not less than 40%, still more preferably not
less than 50% of the club head width.
Here, the club head width is a distance measured in the toe-heel
direction, in the front view of the club head under the standard
state, between a toe-side extreme end and a heel point positioned
at a height of 22.23 mm from the horizontal plane HP.
[0076] In the above-described embodiments shown in FIGS. 6 and 7 in
which the weight member 11 is attached to the head main body 10 by
the use of screws, the position of the weight member 11 is
substantially fixed.
[0077] However, it is also possible to construct the club head
according to the present disclosure such that the position of the
weight member 11 is adjustable in at least one direction, for
example, a front-back direction, up-down direction or toe-heel
direction of the club head.
[0078] FIGS. 9-12 show a variety of examples of such adjusting
mechanism for changing the position of the weight member 11.
[0079] Hereinafter, such examples of the adjusting mechanism will
be described with reference to the drawings.
For convenience' sake, an adjusting mechanism for changing the
position of the weight member 11 in the front-back direction of the
club head is called "front-back adjusting mechanism 50", an
adjusting mechanism for changing the position of the weight member
11 in the up-down direction of the club head is called "up-down
adjusting mechanism 60", and an adjusting mechanism for changing
the position of the weight member 11 in the toe-heel direction of
the club head is called "toe-heel adjusting mechanism 70".
[0080] As to other parts than the adjusting mechanism of each of
the following embodiments not described below, the descriptions
made in connection with the former embodiments may be applied
thereto.
[0081] FIG. 9 schematically shows a lower part of the head main
body 10 of a club head as another embodiment of the present
disclosure.
[0082] In this embodiment, the club head is provided with the
front-back adjusting mechanism 50 and the up-down adjusting
mechanism 60.
[0083] It is, of course, possible to provide either one of the
front-back adjusting mechanism 50 and the up-down adjusting
mechanism 60 as another embodiment of the present disclosure.
[0084] The front-back adjusting mechanism 50 comprises front-back
slotted holes 51 formed in the head main body 10 so as to extend in
a front-back direction of the club head, and screws 52 respectively
penetrating through the front-back slotted holes 51 and fixing the
weight member 11 to the head main body 10 at a desired
position.
[0085] In this example, the front-back slotted holes 51 are formed
in the side portion 5.
Preferably, the front-back slotted holes 51 include a toe-side
front-back slotted hole 51a disposed in a toe-side of the side
portion 5, and a heel-side front-back slotted hole 51b disposed in
a heel-side of the side portion 5. Each of the front-back slotted
holes 51a and 51b extends substantially parallel with the
above-mentioned horizontal plane HP in the standard state of the
club head.
[0086] Each of the screws 52 comprises a screw axis 52a having a
diameter less than the width of the front-back slotted hole 51
through which the concerned screw 52 is penetrated, and a screw
head 52b having a diameter more than the width of the same
front-back slotted hole 51.
For example, the screws 52 are penetrated through the respective
front-back slotted holes 51 from the outside of the head main body
10, and inserted into respective threaded holes 27 and 28 of the
weight member 11. In this embodiment, a screw 52 penetrating
through the toe-side front-back slotted hole 51a is screwed into
the toe-side threaded hole 27 of the weight member 11, and a screws
52 penetrating through the heel-side front-back slotted hole 51b is
screwed into the heel-side threaded hole 28 of the weight member
11. Thus, the weight member 11 may be fixed to the head main body
10 at an arbitrary position owing to the friction between the head
main body 10 and the screw head 52b of each screw 52, for example.
At this time, the weight member 11 may be supported without
contacting the sole portion 4 of the head main body 10.
[0087] If it is desired to change the position of the weight member
11 in the front-back direction of the club head, for example, one
of the screws 52 is loosened so as not to completely fall out of
the weight member 11, and
the screws 52 on both sides are moved forward or backward along the
respective front-back slotted holes 51 to move the weight member 11
in the club head accordingly, together with the screws 52. Then,
the screws 52 are tightened to fix the weight member 11 at a
desired position. Therefore, the position of the center of gravity
of the head in the front-back direction may be adjusted.
[0088] Preferably, the front-back slotted holes 51 are closed or
covered with a detachable cover after adjusting the position of the
weight member 11.
[0089] The up-down adjusting mechanism 60 comprises up-down slotted
holes 61 formed in the head main body 10 to extend in an up-down
direction of the club head, and screws 62 respectively penetrating
through the up-down slotted holes 61 and fixing the weight member
11 to the head main body 10 at a desired position.
[0090] In the embodiment shown in FIG. 9, the screws 62 double as
the screws 52 in the front-back adjusting mechanism 50.
[0091] In this example, the up-down slotted holes 61 are formed in
the side portion 5.
Preferably, the up-down slotted holes 61 include at least one
toe-side up-down slotted hole 61a disposed in a toe-side of the
side portion 5, and at least one heel-side up-down slotted hole 61b
disposed in a heel-side of the side portion 5. In the example shown
in FIG. 9, more than one toe-side up-down slotted holes 61a and
more than one heel-side up-down slotted holes 61b are provided.
[0092] If it is desired to change the position of the weight member
11 in the up-down direction of the club head, for example, one of
the screws 62 is loosened so as not to completely fall out of the
weight member 11, and the screws 62 on both sides are moved up or
down along the respective up-down slotted holes 61 to move the
weight member 11 in the club head accordingly, together with the
screws 62 as shown in FIG. 10.
Then, the screws 62 are tightened to fix the weight member 11 at a
desired position. Therefore, the position of the center of gravity
of the head in the up-down direction may be adjusted.
[0093] In the embodiment shown in FIG. 9, the up-down slotted holes
61 are preferably arranged to extend across the front-back slotted
holes 51.
In this embodiment, the position of the weight member 11 is
adjustable with respect to two directions, the front-back direction
and the up-down direction of the club head. Accordingly, the
position of the center of gravity of the head is adjustable in the
front-back direction and the up-down direction of the club
head.
[0094] Preferably, the up-down slotted holes 61 are closed or
covered with a detachable cover after adjusting the position of the
weight member 11.
[0095] FIG. 11 schematically shows a lower part of the head main
body 10 of a club head as another embodiment of the present
disclosure.
[0096] In this embodiment, the club head is provided with the
toe-heel adjusting mechanism 70 and the front-back adjusting
mechanism 50.
[0097] It is, of course, possible to provide either one of the
toe-heel adjusting mechanism 70 and the front-back adjusting
mechanism 50 as another embodiment of the present disclosure.
[0098] The toe-heel adjusting mechanism 70 comprises toe-heel
slotted holes 71 formed in the head main body 10 to extend in a
toe-heel direction of the club head, and screws 72 respectively
penetrating through the toe-heel slotted holes 71 and fixing the
weight member 11 to the head main body 10 at a desired
position.
[0099] In this example, the toe-heel slotted holes 71 are formed in
the sole portion 4.
Preferably, the toe-heel slotted holes 71 include at least one
toe-side toe-heel slotted hole 71a disposed in a toe-side of the
sole portion 4, and at least one heel-side toe-heel slotted hole
71b disposed in a heel-side of the sole portion 4.
[0100] In this embodiment, the toe-side toe-heel slotted hole 71a
is formed on a toe-side ridge 73, and
the heel-side toe-heel slotted hole 71b is formed on a heel-side
ridge 73, wherein the ridges 73 are formed by raising the sole
portion 4 locally on both sides of a central part of the sole
portion 4 in the toe-heel direction.
[0101] Each of the screws 72 comprises
a screw axis 72a having a diameter less than the width of the
toe-heel slotted hole 71 through which the concerned screw 72 is
penetrated, and a screw head 72b having a diameter more than the
width of the same toe-heel slotted hole 71. For example, the screws
72 are penetrated through the toe-heel slotted holes 71 from the
outside of the head main body 10, and inserted into respective
threaded holes 75 of the weight member 11. In this embodiment, a
screw 72 penetrating through the toe-side toe-heel slotted hole 71a
is screwed into a toe-side threaded hole 75 of the weight member
11, and a screw 72 penetrating through the heel-side toe-heel
slotted hole 71b is screwed into a heel-side threaded hole 75 of
the weight member 11. Thus, the weight member 11 may be fixed to
the head main body 10 at an arbitrary position by pinching the head
main body 10 between the screw 72 and the weight member 11. At this
time, the weight member 11 may be supported without contacting the
head main body 10 at least in the above-mentioned vertical plane
including the sweet spot of the head, more specifically, between
the toe-side ridge 73 and the heel-side ridge 73.
[0102] If it is desired to change the position of the weight member
11 in the toe-heel direction of the club head, all of the screws 72
are loosened so as not to completely fall out of the weight member
11, and the screws 72 on both sides are moved toward the toe or
heel along the respective toe-heel slotted holes 71 to move the
weight member 11 in the club head accordingly, together with the
screws 72 as shown in FIG. 12. Then, the screws 72 are tightened to
fix the weight member 11 at a desired position. Therefore, the
position of the center of gravity of the head in the toe-heel
direction may be adjusted.
[0103] In the example of the front-back adjusting mechanism 50
provided in the embodiment shown in FIG. 11,
the front-back slotted holes 51 extending in the front-back
direction of the club head are disposed in the sole portion 4, and
the screws 52 penetrate through the front-back slotted holes 51 in
order to fix the weight member 11 to the head main body 10 at a
desired position.
[0104] In this embodiment shown in FIG. 11, the screws 52 double as
the screws 72 of the toe-heel adjusting mechanism 70.
[0105] In this embodiment, the front-back slotted holes 51 are
arranged to extend across the toe-heel slotted holes 71.
[0106] In this embodiment, the position of the weight member 11 can
be changed in two directions, the front-back direction and the
toe-heel direction of the club head. Therefore, the position of the
center of gravity of the head may be adjusted in the front-back
direction and the toe-heel direction of the club head.
[0107] Preferably, the toe-heel slotted holes 71 are closed or
covered with a detachable cover after adjusting the position of the
weight member 11.
[0108] In the above-described examples of the adjusting mechanisms
50, 60 and 70, the slotted holes 51, 61 and 71 are employed instead
of the circular through-holes 23, 26, 33 and 36 employed in the
former embodiments shown in FIGS. 6 and 7.
The slotted holes 51, 61 and 71 may be considered as extending
linearly. For example, in another example of the adjusting
mechanism, slotted holes curved like an circular arc around an axis
extending in the up-down direction may be formed in the sole
portion 4 so that the weight member is movable or rotatable around
the above-mentioned axis.
[0109] While description has been made of preferable examples of
the adjusting mechanism, the front-back adjusting mechanism 50 is
not limited to the illustrated examples. It may be embodied in
various other forms as far as the position of the weight member 11
can be changed in the front-back direction of the club head.
[0110] The up-down adjusting mechanism 60 is not limited to the
illustrated example. It may be embodied in various other forms as
far as the position of the weight member 11 can be changed in the
up-down direction of the club head.
[0111] The toe-heel adjusting mechanism 70 is not limited to the
illustrated example. It may be embodied in various other forms as
far as the position of the weight member 11 can be changed in the
toe-heel direction of the club head.
Comparison Tests
[0112] Wood-type club heads (Ex.1-Ex.7) having specifications shown
in Table 1 were produced experimentally, and the heads were tested
for the rebound performance and measured for the position of the
center of gravity.
Comparative example (Ref.) had a weight member 11 shown in FIG. 8,
wherein the underside of the weight member 11 was firmly fixed to
the inner surface of the sole portion 4 over a length of about 70
mm in the toe-heel direction. Excepting the weight members, all of
the club heads had the same structure, wherein the fore member 10a
of the head main body 10 was made of a stainless CUSTOM455 having a
specific gravity 7.80, and the aft member 10b of the head main body
10 was made of a stainless CUSTOM450 having a specific gravity
7.83.
<Measurements of Properties>
[0113] The club heads were measured for:--
the depth of the center of gravity defined by the distance between
the sweet spot and the center of gravity of the head; the height of
the sweet spot defined by the vertical distance from the sweet spot
to the horizontal plane HP in the standard state; and a moment of
inertia of the head around a horizontal axis extending in the
toe-heel direction passing through the center of gravity of the
head.
<Rebound Performance Test>
[0114] According to the "Procedure for Measuring the velocity Ratio
of a Club Head for Conformance to Rule 4-1e, Appendix II, Revision
2 (Feb. 8, 1999), United States Golf Association.", the restitution
coefficient at a center of the club face was obtained. Here, the
center of the club face is a point positioned on the club face such
that the horizontal distance from the point to the toe-side extreme
end of the club face is equal to the horizontal distance from the
point to the heel-side extreme end of the club face, and the
distance in the up-down direction from the point to the uppermost
end of the club face is equal to the distance in the up-down
direction from the point to the lowermost end of the club face.
The results are indicated in Table 1 by an index based on the
comparative example (Ref) being 100, wherein the larger value is
better.
<Spin Test>
[0115] In the above-mentioned rebound performance test, the spin of
the ball immediately after the launching was measured. The results
are indicated in Table 1, wherein the smaller value is better.
TABLE-US-00001 TABLE 1 Heads Weight member Ref. Ex. 1 Ex. 2 Ex. 3
Ex. 4 Ex. 5 Ex. 6 Ex. 7 Structure (Fig. no.) 8 4 4 6 7 7 4 4 length
W (mm) 0 70 70 70 50 30 70 70 section area *1 C C ITC ITC ITC ITC
ITC ITC material *2 450 450 450 450 450 450 specific gravity 7.83
7.83 7.83 7.83 7.83 7.83 10 16 mass (g) 53 53 53 53 53 53 53 53
Depth of center of gravity (mm) 23 21 20.5 20.5 20.5 20.5 20.3 20.2
Sweet spot height (mm) 22.4 22.6 22.4 22.4 22.2 22.1 22.2 21.9
Moment of inertia (g sq. cm) 1180 1070 1055 1055 1065 1070 1055
1065 Rebound performance 100.0 101.2 101.2 101.2 100.5 100.2 101.5
101.7 Spin (rpm) 2800 2806 2775 2775 2749 2736 2747 2707 *1 C: The
cross section area of the weight member was constant. ITC: The
cross section area of the weight member was increased toward its
center in the toe-heel direction. *2 450: CUSTOM450 Stainless
[0116] From the test results, it was confirmed that, in comparison
with the comparative example head, the club heads according to the
present invention can exert good rebound performance while
maintaining the center of gravity of the head at low and shallow
positions, and thereby the spin of the hit ball is reduced.
[0117] While description has been made of preferable embodiments of
the present invention, the illustrated embodiments should not be
construed as to limit the scope of the present invention; various
modifications are possible without departing from the scope of the
present invention.
* * * * *