U.S. patent application number 10/057526 was filed with the patent office on 2002-06-27 for balanced putting trainer device.
Invention is credited to Foresi, Anthony.
Application Number | 20020082105 10/057526 |
Document ID | / |
Family ID | 23921600 |
Filed Date | 2002-06-27 |
United States Patent
Application |
20020082105 |
Kind Code |
A1 |
Foresi, Anthony |
June 27, 2002 |
Balanced putting trainer device
Abstract
A golf club has a shaft with a proximal end and a distal end. A
golf club head is attached to the distal end of the shaft. The head
has a leading ball-striking face, and a trailing edge with a
striking axis defined generally perpendicular to the striking face
and a transverse axis defined generally parallel to the striking
face. The head includes a polymer insert having a transversely
extending face portion and a generally cylindrical portion
extending rearwardly therefrom along the striking axis. The face
portion has a transverse width greater than the generally
cylindrical portion. A metal shell has a body portion surrounding
the cylindrical portion and a perimeter ridge extending around the
perimeter of the face portion of the polymer insert such that the
perimeter ridge of the metal shell and a face portion of the
polymer insert cooperate to define the ball-striking face of the
golf club head.
Inventors: |
Foresi, Anthony; (Allen
Park, MI) |
Correspondence
Address: |
Douglas L. Wathen
Gifford, Krass, Groh, Sprinkle,
Anderson & Citkowski, PC
280 N. Old Woodward Ave., Suite 400
Birmingham
MI
48009
US
|
Family ID: |
23921600 |
Appl. No.: |
10/057526 |
Filed: |
January 24, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10057526 |
Jan 24, 2002 |
|
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09483804 |
Jan 15, 2000 |
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Current U.S.
Class: |
473/251 |
Current CPC
Class: |
A63B 53/0416 20200801;
A63B 2209/00 20130101; A63B 53/14 20130101; A63B 53/0441 20200801;
A63B 69/3685 20130101; A63B 53/0487 20130101 |
Class at
Publication: |
473/251 |
International
Class: |
A63B 069/36 |
Claims
I claim:
1. A golf club comprising: a shaft having a proximal end and a
distal end; a club head attached to the distal end of the shaft
having a leading ball striking face and a trailing edge, the ball
striking face having a perimeter shape, a width and a height
associated therewith, a striking axis being defined from the ball
striking face to the trailing edge and a transverse axis defined
perpendicular to the striking axis, the club head comprising: a
metal portion having a forward face and a trailing edge, the
forward face having a perimeter ridge defining the perimeter of the
striking face and a recessed central area, a generally cylindrical
bore being defined from the forward face to the trailing edge, the
bore being generally aligned with the striking axis; and a polymer
insert having a generally cylindrical portion filling the bore in
the metal portion and a face portion filling the recessed central
portion of the metal portion and defining the remainder of the
striking face, the face portion having a perimeter shape generally
similar to the perimeter shape of the ball striking face such that
the perimeter ridge has a generally constant width, the face
portion having a transverse width greater than the cylindrical
portion such that the polymer insert has a generally T-shaped
horizontal cross section.
2. The golf club of claim 1, wherein the face portion has a
generally constant thickness.
3. The golf club of claim 1, wherein the face portion has a
thickness of approximately {fraction (1/8)} inch.
4. The golf club of claim 1, wherein the polymer is a viscoelastic
material.
5. The golf club of claim 1, wherein the polymer has a hardness
greater than the hardness of golf ball.
6. The golf club of claim 1, wherein the polymer has a hardness
less than the hardness of a golf ball.
7. The golf club of claim 1, wherein the metal portion is
aluminum.
8. The golf club of claim 1, wherein the head has an upper surface
with a pair of visible parallel lines disposed thereon, the lines
being generally parallel to the striking axis and spaced apart by
the width of a golf ball.
9. The golf club of claim 1, wherein the club is face balanced.
10. The golf club of claim 1, wherein the club head has a lower
surface and the shaft has weight of 300 to 500 grams added centered
on a distance between 17 and 25 inches from the lower surface of
the club head.
11. The golf club of claim 1, wherein the head is a mallet style
putter head.
12. A golf club comprising: a shaft having a proximal end and a
distal end; a golf club head attached to the distal end of the
shaft, the golf club head having a leading ball striking face and a
trailing edge with a striking axis defined generally perpendicular
to the striking face and a transverse axis defined generally
parallel to the striking face, the head comprising: a polymer
insert having a transversely extending face portion and a generally
cylindrical portion extending rearwardly therefrom along the
striking axis, the face portion having a transverse width greater
than the generally cylindrical portion; and a metal shell having a
body portion surrounding the cylindrical portion and a perimeter
ridge extending around the perimeter of the face portion of the
polymer insert such that the perimeter ridge of the metal shell and
the face portion of the polymer insert cooperate to define the ball
striking face of the golf club head.
13. A golf club comprising: a shaft having a proximal end and a
distal end; and a golf club head attached to the distal end of the
shaft, the golf club head comprising: a body having a generally
planar ball striking face and an opposed trailing edge
interconnected by upper and lower surface extending therebetween,
the ball striking face having a metal perimeter and a polymer
central portion; and a generally cylindrical polymer central core
extending from the polymer central portion of the ball striking
face to the trailing edge of the body.
Description
REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of U.S. patent
application Ser. No. 09/483,804, filed Jan. 15, 2000, the entire
contents of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to golf training
devices and, in particular, to an economical, balanced putter
training device that promotes a "perpendicular swing" and/or has an
improved sweet spot.
BACKGROUND OF THE INVENTION
[0003] A wide variety of training devices are available to the golf
enthusiast. With specific regard to putting, many experts now agree
that the ideal stroke is a "pendulum" swing initiated at the
shoulders with the wrists locked about the handle of the club. Many
the training devices accordingly operate to enforce this pendulum
movement. For example, U.S. Pat. No. 3,963,244 discloses a
specialized putter consisting of two shafts in spaced-apart
parallel relation and pivotally attached, one having a lower
ground-engaging member and the other having a putter head, enabling
the user to hold one shaft steady while pivoting the other in a
pendulum motion. This is not a training device, however, but
rather, a specialized putter which operates at 90 degrees relative
to conventional clubs, that is, the stroke is forward and away from
the golfer as opposed to being from side to side.
[0004] More recent putter training and practice devices include
U.S. Pat. No. 4,880,240, which provides a specially constructed
putter and a stroke guide worn at the user's waist wherein a pivot
point is created, rather than at the shoulders. U.S. Pat. No.
5,308,071 includes an extension attachable to the putter grip and a
guide attachable to the waist of a golfer having a narrow
horizontal slot to receive a tab on the extension. In one
embodiment, the pivot point for pendulum action may be moved up
from the waist to the chest area. U.S. Pat. Nos. 5,156,401 and
5,328,185 also teach elongated putters which extend roughly from
the chest area down to the golf club head. In U.S. Pat. No.
5,156,401, the upper end includes a cross piece which abuts the
user's chest and has end portions which extend under the user's
arms to promote and maintain good stance by maintaining a constant
triangular shape defined by the user's shoulders and hands. In U.S.
Pat. No. 5,328,185, one hand is used to grip the upper end of an
elongated putter in the shaft area, while the other hand grips the
club midway, using either a small protruding extension or a
U-shaped handle. U.S. Pat. No. 5,342,055 includes an elongated rod
having a neck-engaging mender and a quick release connector for
attaching the rod to the head of the putter. The length of the rod
is adjustable and defines the radius of the arc of motion of the
club relative to the golfer so that the swing is constrained in a
precisely defined path to teach the golfer a repetitive stroke.
[0005] All of the devices just described present certain drawbacks,
however, either concerning the manner in which they are used, or in
terms of their manufacture. For example, the "pit putter" disclosed
in FIGS. 1 and 2 of my U.S. Pat. No. 5,520,392, is typically
constructed in the same manner as a conventional putter, though it
is much longer to fit under the armpit of a user to promote the
desirable pendulum swing. However, in simply extending the length
of the golf club shaft, sufficient attention may not be made to
weight distribution, resulting in a device which is unbalanced and
less effective for training purposes. Since a device of this kind
is very useful for putting training, the need remains for an
improved, more balanced version of such apparatus, preferably one
wherein manufacturing steps may be integrated to reduce costs to
the consumer.
[0006] There have also been numerous attempts to expand or improve
the "sweet spot" on the head of a golf putter. The sweet spot may
be generally defined as the area on the club face that when used to
strike a golf ball results in the longest putting distance for a
given strength or speed of swing. By expanding and/or improving the
sweet spot, putting results may be improved. U.S. Pat. Nos.
6,302,807 to Rohrer; U.S. Pat. No. 5,575,472 to Magerman et al.;
and U.S. Pat. No. 4,422,638 to Tucker, all of which are
incorporated in their entirety herein by reference, each disclose a
golf club head that is at least partially formed with an
elastomeric portion so as to affect the sweet spot or striking
characteristics of the club. For example, the Rohrer patent
specifies a variable energy absorbing means incorporated such that
maximum energy is absorbed when a golf ball is struck on the
intended strike point and progressively less energy is absorbed as
the ball is struck on the striking face at distances incrementally
remote from the intended strike point along the horizontal axis.
While this approach may help to equalize putting distances from
miss-hit putts, it does little to enlarge the actual sweet spot.
Instead, the design attempts to equalize putting distances whether
the sweet spot is used not. The Tucker patent states that a golf
ball typically has a hardness in the range of, or above, 99
Durometer A and 50 Durometer D at the surface of the ball and that
traditionally elastomers were chosen with a hardness greater than
the hardness of a golf ball. In Tucker, elastomers are specified
with a resiliency above about 45 percent rebound and a minimum
hardness of about 70 Durometer A and preferably a hardness below
the hardness of a golf ball. Despite these attempts, there remains
a need for golf clubs with an improved or expanded sweet spot.
SUMMARY OF THE INVENTION
[0007] The subject invention improves upon prior-art putter
training devices by providing a fully balanced unit manufactured
utilizing integrated fabrication steps to reduce costs. The device
features an elongated shaft having an extent long enough that the
proximal end may fit under the armpit of a user while the distal
end, includes a conventional putter head, may be used to strike a
ball as part of a pendulum swing. The device includes two grips,
one central to the shaft, preferably including a square shape that
locks the wrists, and a second grip covering the proximal end so
that it is more comfortable to the user during application.
[0008] In terms of fabrication, the shaft is preferably molded
around a rigid element. For example, the shaft may be a thermoset,
polymeric material, and the rigid element a metal rod or wire. The
grip is molded around the shaft, preferably using the same mold to
form the shaft around the rigid element. In the preferred
embodiment, a weight is also provided central to the shaft so as to
counter-balance the weight of the putter head, such that, with the
shaft and grip material formed therearound, the resulting device is
balanced not only in terms of swing, but in terms of center of
gravity. In some embodiments, this results in adding the weight of
approximately 400 grams centered on a position about 21 inches from
the sole of the putter. Use of such weight may be applied to a long
pit putter, a mid putter designed to have the upper end placed
against the belly of the golfer, or a standard putter.
[0009] Standard putters (of 31, 32, 33, 34 and 35 inches in
length), as well as mid-putters (designed to have the upper end
placed against the golfer's stomach), may be made in the same mold
die as a longer pit putter. All are preferably face-balanced,
shaft-balanced and counter-balanced, making the manufacturing
process very cost-effective. Locking the long putter in a user's
armpit locks the wrists so that the hands work together. The long
putter allows hands, arms and shoulders to work together as a
triangle, promoting a perfect pendulum "lock-and-roll" stroke.
[0010] In further embodiments of the present invention, a club head
with an improved sweet spot is provided. The club head has a
leading ball striking face and a trailing edge with a striking axis
defined generally perpendicular to the striking face and a
transverse axis defined generally parallel to the striking face.
The golf club head has a polymer insert with a transversely
extending face portion and a generally cylindrical portion
extending rearwardly therefrom along the striking axis. The face
portion has a transverse width greater than the generally
cylindrical portion. The metal shell has a body portion surrounding
the cylindrical portion of the polymer insert and a perimeter ridge
extending around the perimeter of the face portion of the polymer
insert such that the perimeter ridge of the metal shell and the
face portion of the polymer insert cooperate to define the ball
striking face of the golf club head. The polymer insert defines the
majority of the ball striking face so as to alter the feel of the
club. In addition, the cylindrical portion that extends from behind
the ball striking face creates a large sweet spot for improved
putting.
BRIEF DESCRIPTION OF THE DRAWING
[0011] FIG. 1 illustrates, from an oblique perspective, a preferred
embodiment of a long putter according to the present invention;
[0012] FIG. 2 is a perspective view of an improved golf club head
according to one aspect of the present invention;
[0013] FIG. 3 is a perspective view of the golf club head of FIG. 2
showing the trailing edge with the polymer insert extending to the
trailing edge;
[0014] FIG. 4 is a generally horizontal cross-sectional view of the
golf club head of FIGS. 2 and 3 showing the cross-sectional shape
of the polymer insert; and
[0015] FIG. 5 is a generally vertical cross-section taken along
lines 5-5 of FIG. 4.
DETAILED DESCRIPTION OF THE INVENTION
[0016] A preferred embodiment of the invention is depicted
generally at 100 in FIG. 1. The device includes an elongated shaft
102 having a distal end with a putter head 104 that is heel-, toe-
and face-balanced. For example, a curved section 106 may be
provided as is often the case with conventional putters. The shaft
102 is sufficiently long that the proximal end fits under the
armpit of a user, thereby encouraging a pendulum-type swing, as
shown in FIGS. 1 and 2 of my U.S. Pat. No. 5,520,392.
[0017] Central along the shaft 102, there is disposed a first soft
grip 108. The shaft continues to a section 110 which is preferably
smooth and circular in cross-section, before encountering a second
soft grip 112 to ease comfort to the user during use. Although
square grip shapes are shown, round or contoured grips may be
used.
[0018] The device described herein may be manufactured in a number
of ways though, in the preferred embodiment, an integral molding
process is used to save on costs. As part of this process, a mold
is produced having a cavity which conforms to the desired outer
dimensions of the device overall. A face insert 120 is placed into
the mold of the putter head 104, as well as a weight in the central
section 130 of the shaft area (not visible in the figure), and the
weight and insert are connected to one another with a rigid form
such as a metal rod. These internal weights and rigid components
are sized to be somewhat less than the outer dimensions of the
device overall, so that when mold material such as a thermoset
polymer plastic is introduced into the mold, these internal
components are completely covered.
[0019] To further save on manufacturing costs, the same mold is
preferably used to form the grip portions of the device. In
particular, inserts are used in the mold with respect to the first
injection of the thermoplastic material, which forms a hard surface
around the shaft. However, inserts are placed in the mold in the
areas forming grips 108 and 112, and, prior to the first material
completely setting, these inserts are completely removed. A second
injection of softer material is then introduced into the voids
caused by the removal of the inserts, thereby forming the grips 108
and 112, as shown in the figure. Particularly if the harder
material has not yet set, the grip portions will adhere to form a
strong permanent bond to the device.
[0020] According to the present invention, weight may be added to
the shaft of the club 100 as described above, or may be added in
any other way. Typically, a standard length putter shaft weighs
80-100 grams, while the longer shaft 102, without additional
weights, has a weight between 100-200 grams. Referring again to
FIG. 1, the putter may be said to have a sole or lower surface 132,
which defines the lowermost point of the putter 100 in the putting
position. According to one embodiment, a weight of approximately
400 grams is added centered on a position approximately 21 inches
from the lower surface 132 of the club 100. The weight may be very
dense and located specifically on the position, or may be more
spread out such that a portion of the weight is above and below the
center of weight. In one embodiment, the weight is spread out over
a distance of about 4 inches up and down the shaft. Lead weights
may be embedded in the shaft, or other means of achieving the
additional weight may be used. As will be clear to those of skill
in the art, the position of the weight may be adjusted upwardly or
downwardly somewhat, depending on the application. For example, in
some embodiments the center point of the weight may be in a
position ranging between 19 and 23 inches from the lower surface.
In yet other embodiments, the weight may have a center point
position between 17 and 25 inches from the lower surface. Also,
more or less weight may be used depending on the application. For
example, in some embodiments, the weight may range between 380-420
grams. In further embodiments, the weight may vary between 350-450
grams. In yet further embodiments, the weight may range between
300-500 grams. Also, weights in the ranges and positions described
may be used in other lengths of putters. For example, weights may
be provided in a standard putter, having an overall length of 31-35
inches. Also, weights may be provided in a mid-length putters,
known as a mid-putter or belly anchor putter. A mid-putter has an
overall length designed to allow the golfer to place the proximal
end against their stomach and to pivot the stomach along with the
upper body to swing the club. Once again, weights in the ranges and
positions described may be placed in a mid-putter, or a standard
length putter.
[0021] Referring now to FIGS. 2 and 3, a preferred golf club head
for a putter will be described. This head design may be used with a
standard length putter, a mid putter, or a long putter, such as
shown in FIG. 1. Also, the head design may be used with the weights
as previously described. The golf club head 200 is connected to a
shaft 202, which may be of various lengths. The illustrated golf
club head 200 is of the type described as a mallet style head with
a generally puck-shaped body 204 that is truncated at the leading
edge to provide a ball-striking face 206. The body 204 may be said
to extend from the leading ball-striking face 206 to a trailing
edge 218 and have an upper surface 208 and a lower surface 210.
According to the present invention, the body 204 is composed
primarily of a metal, such as aluminum with a polymer insert
defining a portion of the ball-striking face 206 and extending
through the body. The club head 200 may be said to have a striking
axis A extending from the ball striking face 206 to the trailing
edge 218. The striking axis is generally aligned with the axis of
movement of the golf club head at the moment of ball striking and
may be said to extend generally perpendicularly to ball striking
face 206. A transverse axis B may be defined as generally
perpendicular to the striking axis A and parallel to the face 206.
As illustrated, the ball striking face 206 may be said to have a
perimeter portion 212 formed of the metal material and a central
portion 214 formed of a polymer material. As shown, the polymer
central portion 214 has a perimeter shape similar to the perimeter
shape of the entire striking face 206, such that the perimeter
portion 212 is generally narrow, and may have a generally constant
width. Therefore, the polymer portion 214 defines a majority of the
ball striking face, and in some embodiments may define the entire
face. The polymer portion 214 of the face 206 is preferably
generally planar with a generally constant thickness of 1/8 of an
inch or more. Described in another way, the metal portion of the
club head 200 may be said to have a perimeter ridge 212 defining a
portion of the face 216 with a central recessed area that is filled
by the polymer portion 214.
[0022] In one embodiment, the mallet style putter head has a
transversed width of approximately 4 1/4 inch, a height of
approximately 1 inch, and a length (from striking face 206 to the
trailing edge 218) of approximately 2 3/8 inch. However, the
present invention may be used with putter heads of other shapes,
sizes, and styles. The polymer portion 214 may be any of several
various materials, including plastics, composites, and rubber
materials, as well as other materials differing from the metal
portion of the body 204. In some embodiments, the polymer has a
hardness less than a typical golf ball, while in other embodiments
the hardness is greater than a typical golf ball. The polymers used
for the polymer insert may be of various levels of elasticity and
energy absorption. For example, in some embodiments, highly elastic
and/or highly energy absorbing polymer may be used, while in other
embodiments a more inelastic and/or less energy absorbing polymer
may be used.
[0023] As best shown in FIGS. 3, 4 and 5, a cylindrical bore 215 is
defined from the ball striking face 206 to the trailing edge 218
through the metal body 204. This generally cylindrical bore 215 is
filled with a polymer 216. The polymer 216 is preferably the same
as the polymer 214, though differing materials may be used. As best
shown in FIG. 4, the polymer face portion 214 has a significantly
greater transverse width than the cylindrical portion 216, thereby
giving the polymer portion of the golf club head a generally
T-shaped horizontal cross-section. In some embodiments, the bore
215 is approximately 3/4 of an inch in diameter. In other
embodiments, the bore may be larger or smaller, or may taper. Also,
the bore may be of different shapes, including having an octagonal
or square vertical cross-sectional shape. The transition between
the polymer face portion 214 and the cylindrical portion 216 is
shown as a square corner. However, this transition may be beveled
or radiused.
[0024] The golf club head 200 may be manufactured by first forming
an aluminum body. The recess of the front face may then be machined
and a bore drilled along the striking axis. The recess and bore may
then be filled with a polymer material. Preferably, the striking
face 206 is then remachined to create a generally flat face. The
polymer insert 214 and the aluminum perimeter 212 cooperate to form
the striking face 206. As shown in FIGS. 2 and 3, the upper surface
208 of the golf club head 200 preferably has dual alignment grooves
220 extending generally parallel to the striking axis. The
alignment grooves 220 preferably are spaced apart by a distance
equal to the diameter of the golf ball. This helps a golfer to
align the golf ball with the sweet spot of the club head 200.
[0025] Preferably, the mallet-style golf club head 200 is heavier
front-to-back than other designs, thereby allowing for a more
controlled putting stroke. This assists in creating a properly
counter-balanced putter. The mallet-style head is also preferably
face-balanced. A face-balanced putter may be described as one
having the weight equally distributed, heel to toe, about the
longitudinal axis of the golf club shaft or the axis of rotation of
the golf club shaft. The club head may also be heel-toe balanced,
as described in U.S. Pat. No. 5,961,400, which is incorporated
herein in its entirety by reference. The wide sole of the
mallet-style club head contributes to a stable, consistent stroke
while the head's extra mass offers a firm and confident feel.
Preferably, the mallet-style putter head has most of the head
weight located behind the ball-striking area. In embodiments
including shaft weights, as previously described, this weighting of
the putter head in combination with the weight in the shaft
contributes to the putter being "triple-balanced." That is, the
putter is face-balanced, shaft-balanced (as caused by the weight in
the shaft), and counterweight-balanced by the weight in the head
close to the ground to promote a pure pendulum stroke. Testing
using a testing robot has validated these affects. The T-shaped
polymer insert with its larger sweet spot preferably creates more
dwell time (contact time between golf ball and striking face),
thereby helping to eliminate the skid and bounce of the ball after
impact. Robot testing also indicated a 1/4 inch in deviation from
the sweet spot resulted only in a minimal loss of distance.
[0026] While the present specification and drawings are directed to
preferred embodiments of the present invention, those of skill in
the art will appreciate that alterations may be made without
departing from the scope of the present invention. It is following
claims, including all equivalents, which define the scope of the
present invention.
* * * * *