U.S. patent application number 12/685220 was filed with the patent office on 2010-07-01 for golf club head.
Invention is credited to William R. Weaver.
Application Number | 20100167839 12/685220 |
Document ID | / |
Family ID | 41717585 |
Filed Date | 2010-07-01 |
United States Patent
Application |
20100167839 |
Kind Code |
A1 |
Weaver; William R. |
July 1, 2010 |
Golf Club Head
Abstract
A golf club head is disclosed. The head has a shell with an
inner surface defining a hollow interior portion. The inner surface
has a plurality of inwardly extending ribs made of resin and a
single continuous filament located in the resin.
Inventors: |
Weaver; William R.; (Toledo,
OH) |
Correspondence
Address: |
MARSHALL & MELHORN, LLC
Four SeaGate - 8th Floor
Toledo
OH
43604
US
|
Family ID: |
41717585 |
Appl. No.: |
12/685220 |
Filed: |
January 11, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11435653 |
May 17, 2006 |
7670532 |
|
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12685220 |
|
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|
|
60681783 |
May 17, 2005 |
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Current U.S.
Class: |
473/346 |
Current CPC
Class: |
B29C 45/14549 20130101;
B29C 70/32 20130101; B29L 2031/5227 20130101; Y10S 264/44 20130101;
B29C 53/822 20130101; B29C 53/564 20130101; B29C 33/52 20130101;
B29C 70/345 20130101; B29C 45/4457 20130101 |
Class at
Publication: |
473/346 |
International
Class: |
A63B 53/04 20060101
A63B053/04 |
Claims
1. A golf club head, comprising a shell having an inside surface
and an outside surface, said inside surface defining a
substantially hollow interior portion of said shell and wherein
said inside surface has a plurality of inwardly extending ribs,
wherein said ribs and said shell being substantially comprised of a
resin and a single continuous filament located within said resin.
Description
RELATED APPLICATIONS
[0001] This application is a division of Ser. No. 11/435,653, filed
May 17, 2006, which is incorporated by reference in its entirety
and which is pending as of the filing date of this application.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to golf club heads, more
particularly of the composite metal "wood" type, and a method of
making golf club heads.
[0004] 2. Description of the Background and Relevant
Information
[0005] Wood-type golf club heads traditionally were made from wood,
e.g., persimmon. However, with advances in materials, wood-type
golf club heads are currently predominantly made from high
performance metals such as titanium, and other materials such as
fiber-reinforced plastics. Many club heads made from fiber resin
composite materials are compression molded around relatively rigid
molding cores. In instances where a hollow interior cavity is
desired, dispersible cores made from meltable materials such as wax
or low melting point metals have been employed.
[0006] Wood-type club heads made predominantly of metal may be
fabricated by welding or adhesively joining together edges of two
or more thin sections of a club head shell made of metal such as
stainless steel, beryllium copper, aluminum, titanium, etc.,
thereby producing a one-piece shell.
[0007] For some years now, heads made entirely of a composite
material, with the exception of the sole, have been manufactured.
Such types of constructions are rarely favored by professional
players because they are most often made of a single element, by
the compression molding method, without any particular regard to
the distribution of mass.
[0008] A head made of a plastic material is disclosed in British
Patent Publication No. 2,128,539. This head is made of a single
thermoplastic element injected into a mold around a meltable core.
The head thus manufactured does not allow a good control over the
trajectory of the balls because the problem of balancing the club
is not resolved.
[0009] U.S. Pat. No. 5,000,454 discloses a head made of a
reinforced plastic material and comprising an element acting both
as the reinforcement of the striking face and as the balancing
weight. However, such a structure does not yet permit the club to
be balanced satisfactorily.
[0010] U.S. Pat. No. 6,824,636 B2 is directed to a method for the
manufacture of a hollow three-dimensional fiber golf club head
wherein a fluid-removable core shaped in the general form of the
golf club head is placed in a flexible pressurizable bladder
surrounding the core. At least one ply fiber impregnated with a
curable resin is wrapped over the core and bladder, and a cured
part is formed by pressurizing the bladder while the core, bladder
and impregnated fiber is in a female mold to force the plies
against the inner surface of the mold. After heating to cure the
resin, the bladder and the fluid removable core is removed from the
interior of the cured part by disintegrating the core with a fluid
sufficient to allow removal of the bladder. This method is complex
and difficult of reproduction on a commercial scale.
SUMMARY OF THE INVENTION
[0011] It is an object of the present invention to overcome the
disadvantages inherent to the above described and traditional
methods and resulting structures of club heads, and to provide a
new head design as well as a new method of manufacturing such
head.
[0012] Thus, one of the more specific objects of the invention is
to provide a manufacturing method enabling a more efficient new
head structure to be obtained, especially as regards distribution
of mass, durability, and finishing quality. The method according to
the invention is particularly adapted to the large scale production
of elements requiring a minimum number of operations to produce
what might be considered a complex yet highly advantageous golf
club head.
[0013] Thus, according to the invention, a method of manufacturing
a golf club is disclosed. The method is comprised of the following
steps. A single continuous filament is wound multiple times about a
soluble core. The wound core is then located in a mold. The wound
core is then pressure coated with a resin in the mold. The resin
disperses among the filament windings. The resin is allowed to cure
and form a filament and resin shell about the core. The soluble
core is then removed from the shell while the continuous filament
is retained within the shell.
[0014] The shell has an inside surface and an outside surface. The
inside surface defines a substantially hollow interior portion and
the inside surface has a plurality of ribs that extend into the
interior portion. The ribs and the shell are substantially
comprised of the resin and the single continuous filament located
within the resin.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The above, as well as other advantages of the present
invention, will become readily apparent to those skilled in the art
from the following detailed description when considered in the
light of the accompanying drawings in which:
[0016] FIG. 1 is a schematic, perspective view of an embodiment of
a component for use in the method of the present invention;
[0017] FIG. 1A depicts a cross-sectional view of a mold for forming
the component depicted in FIG. 1;
[0018] FIG. 2 is a schematic view of one embodiment of a filament
winding machine and the component of FIG. 1 of the present
invention;
[0019] FIG. 3 is a schematic, cross-sectional view of one
embodiment of a mold for use in the method of the present
invention;
[0020] FIG. 4 is a schematic, perspective view of another component
of the present invention;
[0021] FIG. 5 is a schematic, cross section of a preferred
embodiment of a structure for creating a shaft-receiving portion in
the present invention;
[0022] FIG. 6 is a schematic, perspective view of one embodiment of
the present invention;
[0023] FIG. 7 is a schematic, perspective view of one embodiment of
the present invention;
[0024] FIG. 8 is a schematic, cut-away view of one embodiment of a
club head of the invention;
[0025] FIG. 9 is a schematic, perspective view of one embodiment of
the bottom of a club head of the invention; and
[0026] FIG. 10 is a schematic, perspective view of one embodiment
of a club head produced in accordance with the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] It is to be understood that the invention may assume various
alternative orientations and step sequences, except where expressly
specified to the contrary. It is also to be understood that the
specific devices and processes illustrated in the attached
drawings, and described in the following specification are simply
exemplary embodiments of invention. Hence, specific dimensions,
directions or other physical characteristics relating to the
embodiments disclosed are not to be considered as limiting, unless
expressly stated otherwise.
[0028] Referring to FIG. 1, a preferred embodiment of a golf club
head core 20 is depicted. The golf club head core 20 is preferably
made by the process and materials described in U.S. Pat. No.
3,692,551, which is incorporated by reference in its entirety into
the present specification.
[0029] By way of example only, FIG. 1A depicts a preferred
embodiment of a mold 11 which may be used to form the core 20
depicted in FIG. 1. The mold 11 preferably has a first half 12 and
a second half 13 which are separable from one another. The first
half 12 and the second half 13 define an interior chamber 14 having
a substantially similar shape to the shape of the core 20. A core
front face block 15 is preferably located with the interior chamber
14. The core front face block 15 has a plurality of ribs 16
extending into the interior chamber 14. The ribs 16 will be used to
form grooves in the front face of the core 20, which are described
in detail below.
[0030] A plurality of ribs 19 extend into the interior chamber 14
from the first half 12 and the second half 13. The ribs 19 will be
used to form grooves in the upper surface of the core 20 and the
lower surface of the core 20, as described below.
[0031] Those skilled in the art will appreciate that the core front
face block 15 may have any design, including any pattern of ribs or
shapes to create a core 20 having any desired shape.
[0032] The mold 11 preferably has at least one sprue 19A for
introducing the core material (not shown) into the interior chamber
14 from outside of the mold 11. The mold 11 may have means to heat
or cool to solidify the core material so that the core material
conforms to the core front face block 15. Alternatively, if the
core material does not require heat and/or cooling to set up, then
such means are not required. The ribs 16, 19 extending into the
interior chamber 14 from the core front face block 15 form grooves
in the core material, discussed below. The heat and/or pressure, if
required, exerted by the mold 11 on the core material create a core
20 which, in a preferred embodiment, looks like the core 20
depicted in FIG. 1.
[0033] Referring to FIG. 1, the core 20 is preferably shaped to
have a somewhat curvilinear front face 26, a curvilinear upper
surface 28 and the curvilinear lower surface 24. In FIG. 1, the
core 20 is located upside down so that at least two core prints 112
can be clearly seen.
[0034] Preferably, an insert 30 is at least partially formed into
the core 20 about each core print 112. The insert 30, thus, is
positioned within the core 20 when the core 20 is formed as
described above. The insert 30 may have a first circumferential
ring 31A (seen in FIG. 3) which helps secure the insert 30 in the
core 20. The insert 30 also preferably has a second circumferential
ring 31B (seen in FIGS. 1 and 3) which will be received within a
resin, described in more detail below.
[0035] As best seen in FIG. 9, the inserts 30 are preferably
cylindrical in shape with a hollow interior portion 30A. The
inserts 30 have a threaded inner surface 30B.
[0036] The upper surface 28 and the lower surface 24 preferably
taper away from the front face 26 until they meet at a rearward
portion 32 of the core 20. Side portions 34 of the upper and lower
surfaces 24, 28 also preferably taper toward one another. Although
a preferred embodiment of the upper and lower surfaces 24, 28 is
depicted in the figures, those skilled in the art will appreciate
that the core 20 can be constructed with any number of surfaces,
edges, depressions or curves and have any shape or size. By way of
example only, the upper and lower surfaces 24, 28 can taper to a
rear surface (not shown), rather than to a rounded edge 36.
Additionally, the side portions 34 of the upper and lower surfaces
24, 28 can taper to side surfaces 34, rather than to rounded side
edges 38, as shown in FIG. 1.
[0037] In the preferred embodiment, a depression 40 in the core 20
is provided adjacent one side of the front face 26. The depression
40 will be used to form a portion of the finished golf club head
that will receive a shaft, as described in more detail below.
[0038] Preferably, the at least two core prints 112 extend away in
a substantially perpendicular fashion from the lower surface 24 of
the core 20. Each core print 112 is preferably positioned in an
area of the lower surface 24 of the core 20 adjacent one of the
side portions 34. The core prints 112 can be positioned in any area
on the lower surface 24 between the front face 26 and the rearward
portion 32 of the core 20. However, in the preferred embodiment,
the core prints 112 are closer to the rearward portion 32 than the
front face 26 of the core 20 to lower the center of gravity of the
finished golf club head.
[0039] Referring to FIG. 1, a plurality of grooves 42 is preferably
located across the front face 26, the lower surface 24 and the
upper surface 28 of the core 20. The grooves 42 extend diagonally
across the front face 26 of the core 20 to intersect one another;
however, it is within the scope of the present invention to extend
the grooves 42 across the front face 26 in any orientation, whether
intersecting or not. Additionally, although FIG. 1 depicts the
grooves 42 continuously extending across the face 26, it is within
the scope of the present invention to interrupt one or more of the
grooves 42, either on the front face 26 of the core 20, or in any
other area of the core 20. The preferred embodiment of the
invention also locates the grooves 42 at a constant depth in the
core 20, although variable depths are within the scope of the
invention.
[0040] In the preferred embodiment, the grooves 42 extend from the
front face 26 rearward across the lower surface 24 of the core 20
and rearward from the front face 26 across the upper surface 28 of
the core 20. Although the grooves 42 are depicted as parallel to
one another on the lower surface 24 of the core 20, and they are
preferably located parallel to one another on the upper surface 28,
it is within the scope of the present invention for the grooves 42
to extend in a non-parallel fashion across the lower surface 24 and
the upper surface 28 of the core 20.
[0041] As shown in FIG. 2, the above-described core 20 is located
in a filament winding machine 44, known to those skilled in the
art, for winding a continuous filament 46 about a workpiece.
Filament winding machines 44 within the scope of the present
invention, but which in no way limit the present invention, are
those made by McClean Anderson of Schofield, Wis. Such machines 44
typically have a supply of filament 48 on at least one spool 50.
The spool 50 is preferably moveable via control by a computer (not
shown) through multiple axes of rotation with respect to the core
20 located in a bit mechanism 52.
[0042] The bit mechanism 52 comprises a tapered point 54 on one end
for engaging one side portion 34 of the core 20 and a clamp 56 on
the other end for engaging the opposite side portion 34 of the core
20. The clamp 56 may be, by way of example, a contoured fit split
clamp. Preferably, the bit mechanism 52 is rotated about at least
one axis by a motor (not shown) controlled by the same computer to
coordinate the rotation of the bit mechanism 52 with the movement
of the spool 50.
[0043] Machines capable of having a plurality of supplies of
filament 48 and which are capable of controlling more than one
spool 50 to simultaneously wind a plurality of cores 20 are also
within the scope of the present invention.
[0044] In the preferred embodiment, the filament 46 on the filament
winding machine 44 is a continuous strand of carbon fiber filament.
Other continuous strands of filament 46, such as Kevlar.RTM.
manufactured by the E.I. Du Pont Nemours Company of Wilmington,
Del., may be used without departing from the scope of the present
invention. Regardless of the composition of the filament 46
selected, the filament 46 should have physical and performance
characteristics comparable to carbon fiber filament or Kevlar.RTM.
filaments.
[0045] The filament-winding machine 44 may also comprise one or
more tensioners 58 for providing a pre-determined amount of tension
to the filament 46. The machine 44 may also comprise a resin
dispenser (not shown) or a resin bath or drum (not shown) for
applying resin to the filament 46.
[0046] In the preferred embodiment, the filament 46 is first wound
into the grooves 42 of the core 20. By way of example only, the
filament 46 is started in one groove 42 on one side portion 34 of
the core 20 and the filament 46 is wound across the core 20 in a
first direction 60. When the filament 46 is wound about the last
groove 42 on the opposite side portion 34 of the core 20, the
filament 46 is moved inwardly to continue winding across the
channels 42 in a second direction 62. Those skilled in the art will
appreciate that the first and second directions 60, 62 can be
reversed from those depicted in FIG. 2.
[0047] Preferably, filament 46 is repeatedly wound within the
grooves 42 as described above until the filament 46 within the
grooves 42 is substantially planar with the front face 26, the
upper surface 28 and/or the lower surface 24. In the preferred
embodiment, the same strand of continuous filament 46 is then wound
across the front face 26, the upper surface 28 and the lower
surface 24 to substantially cover each of those surfaces. The
filament 46 is preferably wound across the core 20 from the first
direction 60 to the second direction 62. The present invention also
includes winding the filament 46 across the core 20 in any pattern,
design or orientation after the grooves 42 have been wound. The
curvilinear shape of the core 20 may prevent winding the entire
core 20 in substantially one direction as the filament 46 can slide
off one of the side portions 34, however, it is preferred to cover
each of the surfaces 26, 28, 24 as much as possible with a uniform
layer of filament 46.
[0048] In the preferred embodiment, the core 20 is wrapped in the
continuous strand of filament 46 to provide a layer of filament 46
above at least one of the surfaces 24, 26, 28 of the core 20 from
approximately one five thousandths (0.005'') of an inch to one
ninety thousandths (0.090'') of an inch.
[0049] In another embodiment, the core 20 may be wrapped, e.g.,
vertically, with additional filament 46 after the initial layer of
continuous filament 46 has been completed. The additional filament
46 may be continuous or non-continuous and it may be located across
the entire core 20, or only selected portions of the core 20, for
example, the ends. The additional filament 46 may be of the same
material as the initial layer, or it may be of a different
material.
[0050] The wound core 20 is then removed from the filament-winding
machine 44 and located in a mold. A preferred embodiment of a
cross-section of a mold is depicted in FIG. 3. The mold may be an
injection mold, a transfer mold, or a compression mold, as known by
those skilled in the art.
[0051] In the embodiment depicted in FIG. 3, a transfer mold 64 is
shown. The mold 64 has a material reservoir 66 in fluid
communication with a chamber 68 via at least one channel 70. One or
more electric coils 72 are located throughout the mold 64 for
heating the mold 64, although channels (not shown) for heated oil
and/or steam may also be used in conjunction with the electric
coils 72 or alone.
[0052] A removable insert 74 is located within the chamber 68. The
insert 74 has a wall 76 having a complementary shape to at least
the wound front face 26 of the core 20. Inserts 74 having walls 76
at various angles, which determines loft in degrees of the club
face, and sizes with respect to the wound front face 26 of the core
20 may be used to locate a face plate 78 at various desired
angles.
[0053] The present invention also comprises the face plate 78 and a
sole plate 80, as shown in FIGS. 3 and 4. The face plate 78 and the
sole plate 80 may be two separate pieces, but preferably, the face
place 78 and the sole plate 80 have either been welded together,
integrally formed together, or otherwise joined. The face plate 78
and the sole plate 80 are preferably constructed of a highly wear
resistant material, such as titanium, titanium alloys or steel
alloys, for instance stainless steel. An outer surface 82 of the
face plate 78 may have one or more vertical and/or horizontal
grooves 86. The grooves 86 help impart, or decrease, spin to a golf
ball depending on groove design.
[0054] Face plates 78 and sole plates 80 of various sizes and
shapes may be used to create club heads having different
appearances. By way of example only, a face plate 78 that is
slightly larger than the wound core 20 may be used, or a face plate
78 that is about the same size as the wound core 20 may be used. In
the latter embodiment, the face plate 78 will be substantially
flush with the finished club head. In the former embodiment, the
face plate 78 will be slightly larger than the finished club
head.
[0055] In the preferred embodiment, the face plate 78 and the sole
plate 80 are located within the mold 64 adjacent the removable
insert 74, as shown in FIG. 3. The mold 64 and at least one wall 76
of the insert 74 may be designed to securely receive the face plate
78 and/or sole plate 80 to prevent movement of the core during the
molding step described below. For example, the mold 64 and wall 76
may have a complementary shape to the face plate 78 and/or the sole
plate 80. Alternatively, it is well within the scope of the present
invention to locate one or more mechanical fasteners (not shown),
such as screws or pins, into the face plate 78 and/or sole plate 80
to removably secure the face plate 78 and the sole plate 80 with
the core 20 in the mold 64.
[0056] Inside surfaces 84 of the face plate 78 and/or the sole
plate 80 may be scored or scuffed, for instance by sand blasting or
other known methods, to provide a gripping surface for the molding
material described below.
[0057] As best seen in FIG. 3, the wound core 20 is located into
the chamber 68 within the mold 64 where the chamber 68 has a
substantially complementary shape to the wound core 20. The core
prints 112 on the core 20 preferably fit into complementary shaped
recesses 85 in the mold 64 to assist in locating the core 20 in a
precise position within the mold 64. Preferably, a predetermined
gap, or wall stock 88, is left between the wound core 20 and the
chamber walls 89.
[0058] Weights to satisfy design criteria, i.e., center of gravity,
may be positioned in the core mold and molded in place. The
weights, if required, will be secured to the club head by the
overmolding step described below.
[0059] Preferably, the wound core 20 is positioned in the chamber
68 so that it is approximately half above and approximately half
below the channel 70. The channel 70 functions as a gate, as known
by those skilled in the art. Those skilled in the art will
appreciate that the core 20 can be located in the chamber 68 in any
position, angle or orientation with respect to the channel 70.
[0060] One or more spacers 90 may also be located between the face
plate 78 and the sole plate 80 and the wound core 20. The spacers
90 may be of any shape, size or dimension. In one embodiment, the
spacers 90 are T-shaped (not shown) to provide a large surface area
with which molding material, described below, comes in contact. The
spacers 90 may have a knurled, or rough, outer surface to assist
them becoming secured within a resin, described below.
[0061] The spacers 90 may be used to provide, i.e., control the
thickness of, the wall stock 88 between the face plate 78, the sole
plate 80 and the wound core 20.
[0062] As shown in FIG. 5, at least one aperture 92 is located in
the face plate 78 and at least one aperture 94 is located in the
sole plate 80. The apertures 92, 94 may be created when the face
plate 78 and the sole plate 80 are formed, or the apertures 92, 94
may be located in the plates 78, 80 after formation, such as by
drilling. A tube 96 is preferably located through the apertures 92,
94 in the face plate 78 and the sole plate 80 and secured by a
press fit or friction fit, adhesive, brazing and/or welding. The
apertures 92, 94 in the face plate 78 and the sole plate 80 are
preferably located and aligned so that the tube 96, when inserted
in the apertures 92, 94, is positioned adjacent the depression 40
in the core 20 for the shaft.
[0063] Referring now back to FIG. 3, a pre-determined quantity of a
thermosetting-engineered resin 98 that is compatible with carbon
fibers, e.g., epoxy or polyester resins, preferably epoxies, is
located in the reservoir 66 of the mold 64. A
thermoplastic-engineered resin that is compatible with carbon
fibers may also be used. In the event a thermoplastic resin is
employed, provision is made to cool the mold to effect cure of the
resin.
[0064] Preferably, non-continuous filaments 100 of carbon and/or
Kevlar.RTM., or filaments 100 having specified physical and
performance characteristics, are equally distributed and suspended
within the resin 98. The resin 98 may be comprised of approximately
20% to approximately 70% filaments 100, but preferably the resin 98
is comprised of approximately 50% filaments 100.
[0065] The thermosetting resin 98 may be liquefied before being
located in the reservoir 66, or it may be liquefied within the
reservoir 66. The various resins 98 which may be used with the
present invention have a liquefying point between 200 degrees
Fahrenheit and 400 degrees Fahrenheit. Typically, the mold 64 is
approximately 300 degrees Fahrenheit to 400 degrees Fahrenheit, so
if the resin 98 is not liquefied before entering the reservoir 66,
it will quickly become liquefied. In either case, the liquefied
resin 98 is urged out of the reservoir 66 by any known means,
including but not limited to, a pump, and/or a plunger 102. The
plunger 102 may be driven by a clamping device such as a hydraulic
press holding the two halves of the mold 64 closed together.
[0066] Those skilled in the art will also appreciate that an
injection type mold can also be used without departing from the
scope of the present invention. In an injection type mold (not
shown), a rotating helical mixing device is located within the
reservoir. The helical mixing device, when rotating, will decrease
the length of any carbon and/or Kevlar.RTM. filaments within the
resin.
[0067] In comparison, the transfer type mold 64 described and
depicted herein does not have a mixing device so that the filaments
100 in the resin 98 retain their original length. Therefore,
depending on the desired filament 100 length in the resin 98,
either the injection type mold or the transfer type mold may be
interchangeably used with the present invention.
[0068] The liquefied resin 98 flows under pressure from the
reservoir 66 and through the channel 70, as through a gate as known
by those skilled in the art. As described above, the wound core 20
is located within the mold 64 so that approximately half of the
wound core 20 is located above the channel 70 and approximately
half of the wound core is located below the channel 70. The
liquefied resin 98 flows in substantially equal quantities around
the wound core 20 in the wall stock 88 about the wound core 20. The
resin 98 also flows around the inserts 30.
[0069] The liquefied resin 98 flows through the wall stock 88 to
overmold the wound core 20. The pressurized resin 98 flows into any
voids not filled by the continuous filament 46 on the core 20 and
it permeates through the filament 46 located over the upper surface
28, the lower surface 24, the filament 46 over the front face 26
and the filament 46 in the grooves 42. The resin 98 is also located
in the wall stock 88 between the wound core 20 and the face plate
78 and the sole plate 80 and between the tube 96 and the wound core
20.
[0070] A fiber filled resin coating (or an unfilled pure resin in
circumstances where the resin is used for an improved surface
finish) over the wound core 20 having a thickness of between
approximately one five thousandths (0.005'') of an inch to
approximately one ninety thousandths (0.090'') of an inch is
desirable.
[0071] The resin 98 is allowed to cure under heat and pressure in
the mold 64 for a pre-determined amount of time. Once the resin 98
is sufficiently cured, the overmolded core 20, now having the face
plate 78, the sole plate 80 and the inserts 30 secured thereto and
the tube 96 secured therein, referred hereinafter as the club head
104, is removed from the mold 64. An outer surface 106 of the club
head 104 that was located adjacent the mold chamber walls 89 now
has a surface dependent on fiber content. For example, the surface
can be smooth, as shown in FIG. 6, or variegated.
[0072] Those skilled in the art will also appreciate that the walls
89 of the chamber 68 can be provided with any surface to provide a
smooth outer surface 106 of the club head 104 or the walls 89 can
be designed to create any design or pattern on the outer surface
106 of the club head 104. By way of example only, the walls 89 of
the chamber 68 can be designed to create a leather-like or
wood-like appearance on the outer surface 106 of the club head 104,
or they can be designed to create a non-reflective surface on the
outer surface 106 of the club head 104.
[0073] In any event, with a soluble core of the type described in
U.S. Pat. No. 3,692,551, in the molded plastic club head 104, the
core material/binder can be quite readily removed from the club
head with water. For example, with a core 20 in which both the
hardened salt binder and skin are water soluble, the head 104 with
the core 20 is placed in a bath of water in a container or tank and
a stream of water employed, with the bath, to dissolve the binder
and flush the core material from the head 104. With this procedure,
the shape of the core 20 is destroyed within the head 104 and the
destruction product or core material dispersed therefrom.
[0074] The liquid/solvent can directly contact the core 20 through
a hole 107. The hole 107 was created during the above-described
molding step as the resin 98 flowed around the insert 30 containing
the core prints 112. Those skilled in the art will appreciate that
one or more holes 107 may be located in the club head 104, such as,
for example, by drilling. The dissolved binder and core material
can be poured out from the club head 104, as shown in FIG. 7.
[0075] FIG. 8 schematically depicts a cut away view of the club
head 104 with the core 20 removed and an insert 30 located in the
club head 104. The overmolded continuous filament 46 in the walls
108 and ribs 110 formed by the grooves 42 of the club head 104 can
be seen. Individual pieces of filament 100 can also be seen in the
walls 108 of the club head 104.
[0076] FIG. 9 depicts the club head 104 with two molded in inserts
30. Those skilled in the art will appreciate that the inserts 30
can also be threaded into place and/or an adhesive or cement can be
used.
[0077] Plugs 114, having a set of complementary threads to the
threaded inserts 30, are threaded into the inserts 30. The plugs
114 cover the hollow inserts 30 and they can also be weighted to
customize the weight of the club head 104. The plugs 114 can be
equally weighted or they can have different weights. Channels 118
within the heads of the plugs 114 have a complementary design to a
Phillips head screwdriver, standard head screwdriver, or hex wrench
so the plugs 114 can be readily inserted or removed.
[0078] Those skilled in the art will appreciate that instead of, or
in addition to, locating the weights as described above, the club
head 104 can be drilled and inserts 30 and plugs 114 can be
inserted in the holes, or weighted inserts can be molded into the
core at selected areas.
[0079] A golf club head shaft 120 is frictionally and/or adhesively
attached through a shaft locator aperture 122 in the face plate 78
and into the club head 104, as shown in FIG. 10. Within the club
head 104, the shaft 120 is located within the tube 96 and secured
thereto with friction and/or an adhesive as known to those skilled
in the art.
[0080] The golf club head 104 assembled according to the steps
described above robustly supports the face plate 78 to reduce, or
prevent, deflection of the face plate 78 upon contact with a golf
ball. Reducing, or preventing, deflection of the face plate 78
decreases energy absorption into the golf club head 104 and
concentrates energy to the golf ball. Additionally, it can be
appreciated that golf club heads 104 made according to the steps
described herein may have different appearances than the preferred
embodiment depicted in FIG. 10. For instance, the walls 108, the
face plate 78 and the sole plate 80 of the club head 104 may have
any shape or size in accordance with United States Golf Association
standards.
[0081] In accordance with the provisions of the patent statutes,
the present invention has been described in what is considered to
represent its preferred embodiments. However, it should be noted
that the invention can be practiced otherwise than as specifically
illustrated and described without departing from its spirit or
scope.
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