U.S. patent application number 09/756237 was filed with the patent office on 2002-07-11 for adjustable length golf club.
Invention is credited to Evans, Robert.
Application Number | 20020091012 09/756237 |
Document ID | / |
Family ID | 25042594 |
Filed Date | 2002-07-11 |
United States Patent
Application |
20020091012 |
Kind Code |
A1 |
Evans, Robert |
July 11, 2002 |
Adjustable length golf club
Abstract
A length adjustment mechanism useful on sports and other working
implements allows the length of an implement to be easily adjusted.
In the case of golf clubs, the length adjustment mechanism includes
a handle with a set of interior threads that engage a set of
exterior threads formed on an upper end of the golf club shaft. The
handle can be screwed down over the threads on the upper end of the
shaft to adjust the length of the club. The handle is then fixed
with respect to the shaft, and a grip is formed over the handle.
The handle can be selectively repositioned along the shaft to alter
the length of the club by freeing the handle, screwing it to a new
position, and re-fixing the handle in the new position.
Inventors: |
Evans, Robert; (Clearwater,
FL) |
Correspondence
Address: |
FLESHNER & KIM,LLP
P.O. Box 221200
Chantilly
VA
20153-1200
US
|
Family ID: |
25042594 |
Appl. No.: |
09/756237 |
Filed: |
January 9, 2001 |
Current U.S.
Class: |
473/296 ;
473/316 |
Current CPC
Class: |
A63B 53/14 20130101;
A63B 60/28 20151001; A63B 60/00 20151001; A63B 60/22 20151001; A63B
2225/093 20130101; A63B 2208/12 20130101 |
Class at
Publication: |
473/296 ;
473/316 |
International
Class: |
A63B 053/16; A63B
053/12 |
Claims
What is claimed is:
1. An adjustable length golf club, comprising: a shaft having
exterior threads formed at an upper end of the shaft; a handle
having an aperture configured to receive the upper end of the
shaft, wherein interior threads that are configured to cooperate
with the exterior threads on the shaft are formed on an inner
surface of the aperture, and wherein the handle can be screwed down
over the upper end of the shaft to adjust a combined length of the
handle and shaft; and a releasable fixation mechanism that
releasably fixes the handle with respect to the shaft.
2. The adjustable length golf club of claim 1, wherein the
releasable fixation mechanism comprises a locking plug having
exterior threads configured to cooperate with the interior threads
of the handle, wherein the locking plug is screwed into the handle,
wherein the locking plug can repositioned within the aperture of
the handle by screwing the locking plug along the threads of the
aperture, and wherein a lower face of the locking plug is
configured to engage an upper end of the shaft to fix the handle
with respect to the shaft.
3. The adjustable length golf club of claim 2, wherein a shaped
socket is formed in an upper face of the locking plug such that a
driver with a shape corresponding to the socket can be used to
reposition the locking plug.
4. The adjustable length golf club of claim 3, wherein an access
hole is formed in an upper end of the handle to allow a driver to
extend through the access hole and into the shaped socket of the
locking plug to engage and reposition the locking plug.
5. The adjustable length golf club of claim 3, wherein the shaped
socket in the upper face of locking plug comprises a hex socket,
and further comprising an access hole formed in an upper end of the
handle to allow a hex driver to extend through the access hole and
into the hex socket to engage and reposition the locking plug.
6. The adjustable length golf club of claim 1, wherein exterior
threads are formed on an exterior surface of a lower end of the
handle, and wherein the releasable fixation mechanism comprises a
locking collar having interior threads configured to cooperate with
the exterior threads on the lower end of the handle, and wherein
screwing the locking collar onto the exterior threads on the lower
end of the handle causes the handle to be compressed against the
shaft to fix the handle with respect to the shaft.
7. The adjustable length golf club of claim 6, wherein an exterior
diameter of the handle increases from the lower end to an
intermediate position, such that as the locking collar is screwed
onto the exterior threads on the lower end of the handle, the
handle will be compressed against the shaft to fix the handle with
respect to the shaft.
8. The adjustable length golf club of claim 6, wherein an inner
diameter of the locking collar decreases from a upper end of the
locking collar to a lower end of the locking collar such that as
the locking collar is screwed onto the exterior threads on the
lower end of the handle, the handle will be compressed against the
shaft to fix the handle with respect to the shaft.
9. The adjustable length golf club of claim 1, wherein the
releasable fixation mechanism comprises: a groove formed on an
outer surface of the upper end of the shaft, wherein the groove
extends along a longitudinal axis of the shaft; and a fastener that
passes through the handle and into the groove to fix the handle
with respect to the shaft.
10. The adjustable length golf club of claim 9, wherein the
fastener comprises a threaded fastener having external threads that
cooperate with internal threads on a fixation aperture that passes
through the handle.
11. The adjustable length golf club of claim 9, wherein a recess is
formed in the handle, and wherein when the fastener is mounted on
the golf club to fix the handle with respect to the shaft, the
fastener is positioned in the recess.
12. The adjustable length golf club of claim 1, further comprising
an insert that is attached to and that forms the upper part of the
shaft, wherein the exterior threads formed at an upper end of the
shaft are formed on the insert.
13. The adjustable length golf club of claim 12, wherein the shaft
is formed of a synthetic or composite material, and wherein the
insert is formed of a metallic material.
14. The adjustable length golf club of claim 1, further comprising
length indicating marks that are formed on the shaft.
15. The adjustable length golf club of claim 14, wherein the handle
and the shaft are configured such that when the handle is
positioned to minimize the combined length of the handle and the
shaft, the handle at least partially covers the length indicating
marks, and wherein as the handle is re-positioned to increase the
combined length of the handle and the shaft, the handle will expose
more of the length indicating marks.
16. The adjustable length golf club of claim 1, further comprising
a grip that is attached to an exterior surface of the handle.
17. An adjustable length golf club, comprising: a shaft having
exterior threads formed at an upper end of the shaft; a handle
having an aperture configured to receive the upper end of the
shaft, wherein interior threads that are configured to cooperate
with the exterior threads on the shaft are formed on an inner
surface of the aperture, and wherein the handle can be screwed down
over the upper end of the shaft such that rotation of the handle
with respect to the shaft adjusts a combined length of the handle
and shaft; and means for releasably fixing the handle with respect
to the shaft.
18. An adjustable length golf club, comprising: a shaft having
upper and lower ends; a club head attached to the lower end of the
shaft; an insert that is inserted into and fixed to the upper end
of the shaft, wherein a portion of the insert protrudes from the
upper end of the shaft, and wherein the protruding portion of the
insert has external threads; a handle having an aperture configured
to receive the protruding portion of the insert and the upper end
of the shaft, wherein interior threads that are configured to
cooperate with the exterior threads on the insert are formed on an
inner surface of the aperture, and wherein the handle can be
screwed down over the insert and the upper end of the shaft to
adjust a combined length of the handle and shaft; and a releasable
fixation mechanism that releasably fixes the handle with respect to
the shaft.
19. The adjustable length golf club of claim 18, wherein the
releasable fixation mechanism comprises a locking plug located in
the handle and having exterior threads configured to cooperate with
the interior threads of the handle, wherein a shaped socket is
formed in an upper face of the locking plug such that a driver with
a shape corresponding to the socket can be used to screw the
locking plug along the threads in the handle to reposition the
locking plug in the handle, and wherein a lower face of the locking
plug is configured to engage an upper end of the insert to fix the
handle with respect to the insert and the shaft.
20. The adjustable length golf club of claim 18, wherein exterior
threads are formed on an exterior surface of a lower end of the
handle, and wherein the releasable fixation mechanism comprises a
locking collar having interior threads configured to cooperate with
the exterior threads on the lower end of the handle, and wherein
screwing the locking collar onto the exterior threads on the lower
end of the handle causes the handle to be compressed against the
shaft to fix the handle with respect to the shaft.
21. The adjustable length golf club of claim 18, wherein the
releasable fixation mechanism comprises: a groove formed on an
outer surface of the insert, wherein the groove extends along a
longitudinal axis of the insert; and a fastener that passes through
the handle and into the groove to fix the handle with respect to
the insert and the shaft.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to devices for providing a golf club
or other implement with length adjustability.
[0003] 2. Background of the Related Art
[0004] When a child first begins to play golf, the length of the
child's golf clubs must be much shorter than clubs used by an
adult. As the child grows, the ideal length of the child's golf
clubs necessarily increases. To address this problem, most
manufacturers create children's golf clubs in about four different
lengths. The four different lengths are intended to provide the
child with a club that is close to the ideal length as the child
matures toward his adult height.
[0005] Unfortunately, when a child first begins to play golf, the
first set of clubs is usually too long. As the child grows in
height, the first set of clubs eventually become the ideal length.
Then, as the child continues to grow, the clubs become too short.
At some point, when the first set of clubs have become noticeably
too short, the child can switch to a new set of clubs having the
second length. At this point in time, the second set of clubs are
too long. This process is repeated four times as the child matures
toward adulthood. With each new set of clubs, the clubs are
initially too long, then just right, then too short again.
SUMMARY OF THE INVENTION
[0006] The invention is a mechanism for adjusting the length of a
golf club or other implement. When applied to golf clubs, such
adjustable length golf clubs can be used in place of the four
different length children's clubs. A golf club embodying the
invention can be adjusted to any of a nearly infinite number of
different lengths between its minimum length and maximum length.
Thus, a set of golf clubs embodying the invention can always be set
to the ideal length for a child, based on his then present height.
This is in stark contrast to the prior art fixed length children's
clubs, which are at a non-ideal length for most of the time, and
which are only at an ideal length for four relatively short periods
of time.
[0007] Because the length can be adjusted, one or two sets of
adjustable length golf clubs embodying the invention can replace
the four different fixed length sets usually used for children as
they grow. This greatly reduces the cost of providing a child with
clubs as he grows to adulthood.
[0008] In an adjustable length golf club embodying the invention,
the top end of the shaft has exterior threads, or an insert with
exterior threads is glued or affixed to the top of the shaft. A
handle, having interior threads that cooperate with the exterior
threads on the top of the shaft, is screwed down over the upper end
of the shaft. A mechanism is then used to fix the handle with
respect to the shaft. A traditional grip can then be mounted over
the handle.
[0009] When the club is first delivered to a customer, the handle
will be fully screwed down over the upper end of the shaft so that
the club has its minimum length. Over time, the handle can be
repositioned by unscrewing it from the top of the shaft to increase
the length of the club. The handle would then be fixed in its new
position.
[0010] In some embodiments of the invention, a series of length
indicating marks can be formed on the upper end of the shaft. When
the handle is fully screwed down over the upper end of the shaft,
the handle will cover substantially all of the length indicating
marks of the shaft. As the handle is un-screwed from the upper end
of the shaft to increase the length of the club, the handle will
gradually uncover more and more of the length indicating marks.
[0011] The invention is not limited to use on children's clubs. An
adjustment mechanism embodying the invention could be used on any
type of golf club that will benefit from length adjustability. For
instance, a length adjustment mechanism could be used on putters so
that an adult golfer could experiment with different putter lengths
to determine an optimum length. In fact, the adjustment mechanism
could be used for all the clubs used by an adult golfer to allow
the golfer to custom tailor the length of each of his clubs to
optimize his golf game.
[0012] Although the foregoing summary of the invention focuses on
the advantages of the invention as used on golf clubs, the
invention is not limited to golf clubs. A length adjustment
mechanism embodying the invention could also be used on other types
clubs and implements to provide length adjustability. For instance,
an adjustment mechanism embodying invention could be used on
baseball and softball bats, tennis, racquetball or badminton
rackets, lacrosse or hockey sticks, kayak or canoe paddles, or any
other type of implement where length adjustability would be
advantageous.
[0013] Additional advantages, objects, and features of the
invention will be set forth in part in the description which
follows, and in part will become apparent to those having ordinary
skill in the art upon examination of the following or may be
learned from practice of the invention. The objects and advantages
of the invention may be realized and attained as particularly
pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The invention will be described in detail with reference to
the following drawings, in which like reference numerals refer to
like elements, and wherein:
[0015] FIG. 1 shows an adjustable length golf club embodying the
invention;
[0016] FIG. 2 is a cross-sectional view showing a disassembled golf
club length adjustment mechanism embodying the invention;
[0017] FIG. 3A is a cross-sectional view showing a golf club length
adjustment mechanism embodying the invention in its minimum length
position;
[0018] FIG. 3B is a cross-sectional view showing a golf club length
adjustment mechanism embodying the invention in its maximum length
position;
[0019] FIG. 4A is a cross-sectional view showing a second golf club
length adjustment mechanism embodying the invention in its minimum
length position;
[0020] FIG. 4B is a cross-sectional view showing the second golf
club length adjustment mechanism embodying the invention in its
maximum length position;
[0021] FIG. 5A is a front view of a portion of a third golf club
length adjustment mechanism embodying the invention;
[0022] FIG. 5B is a right side view of the third golf club length
adjustment mechanism shown in FIG. 5A;
[0023] FIG. 6 is a front view of the third golf club length
adjustment mechanism in an assembled condition;
[0024] FIG. 7 is a cross-sectional view of the golf club length
adjustment mechanism shown in FIG. 6, as taken along section line
7-7; and
[0025] FIGS. 8A, 8B and 8C show an adjustable length golf club
embodying the invention adjusted to three varying lengths.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0026] The following specification describes an adjustment
mechanism for varying the length of a golf club. Although the
description is specific to a golf club, it should be understood
that the invention is equally applicable to other implements where
length adjustability would be desirable. For instance, a length
adjustment mechanism embodying the invention could also be used on
other sports devices such as baseball and softball bats, tennis,
racquetball or badminton rackets, lacrosse or hockey sticks, and
kayak or canoe paddles. In addition, a length adjustment mechanism
embodying the invention could be used on tools and implements such
as rakes, shovels, axes, hammers and other working implements.
[0027] An adjustable length golf club 20 embodying the invention is
shown in FIG. 1. As shown therein, the club 20 includes a shaft 22
attached to a club head 24 and a grip or handle 26. The club is
adjustable between a first length L.sub.1 and a second length
L.sub.2. The length adjustment is accomplished by varying the
position of the grip or handle 26 on the shaft 22.
[0028] A first length adjustment mechanism embodying the invention
which could be used on a golf club is shown in FIG. 2. FIG. 2 shows
a longitudinal cross section of the upper end of a golf club, which
shows the mechanism in a disassembled state.
[0029] In this mechanism, an insert 30 is attached to an upper end
of a golf club shaft 22. A receptacle 28 in the upper end of the
shaft 22 receives a lower portion 32 of the insert 30. A protruding
portion of the insert 30, which protrudes above the shaft 22, is
cylindrical in cross section, and includes exterior threads 34. The
shaft 22 and the lower portion 32 of the insert 30 can have
cylindrical or other cross sectional shapes.
[0030] Several of the embodiments of the invention described in the
specification include an insert mounted on an upper end of a golf
club shaft. However, in other embodiments of the invention, an
upper end of the shaft itself could have a cylindrical cross
section, and the upper end of the shaft could include the external
threads.
[0031] A hollow handle 40 includes an aperture configured to
receive the protruding portion of the insert 30, and the upper end
of the shaft 22. The aperture of the handle 40 includes a smooth
walled portion 46 and a threaded portion 44. The internal threads
44 of the handle are shaped to cooperate with the external threads
34 on the insert.
[0032] A locking plug 50 is also provided inside the hollow handle
40. The locking plug has a cylindrical cross section with exterior
threads on an outer surface thereof. The external threads of the
locking plug 50 are configured to cooperate with the internal
threads 44 of the handle 40.
[0033] An upper face of the locking plug 50 includes a shaped
socket 52 which can be used to reposition the locking plug 50
within the aperture of the handle 40. For instance, the shaped
socket may be a hex head socket which is shaped to confirm to a hex
head wrench.
[0034] Alternatively, the shaped socket 52 could be shaped to
cooperate with a slotted or phillips screwdriver, or some other
type of driving device. The shaped socket 52 would be engaged by an
appropriate driver to screw the locking plug along the threads 44
in the handle 40.
[0035] FIGS. 3A and 3B show the length adjusting assembly of FIG. 2
in two different assembled conditions. In both FIGS. 3A and 3B, the
insert is affixed inside the aperture at the upper end of the shaft
22. In preferred embodiments of the invention, the lower portion 32
of the insert 30 is glued into the aperture 28 of the shaft 22. In
other embodiments of the invention, the insert 30 could be affixed
to the shaft using fasteners such as nails, screws or staples. In
yet other embodiments of the invention, where both the insert 30
and the shaft 22 are metallic, the insert 30 could be welded to the
shaft. In still other alternative embodiments of the invention,
external screw threads on the lower portion 32 of the insert 30
could cooperate with internal threads in the aperture 28 of the
shaft 22 so that the insert can be screwed into the aperture.
[0036] After the insert 30 is attached to the shaft 22, the locking
plug 50 is screwed down the internal threads 44 of the handle 40.
Initially, the locking plug 50 would be screwed substantially all
the way into the handle 40, as shown in FIG. 3A.
[0037] The handle 40, with the associated locking plug 50 would
then be screwed down onto the insert 30 and the upper end of the
shaft 22. Once the handle has been screwed down onto the top of the
shaft so that the combined length of the handle and shaft is at a
desired length, the locking plug 50 would be screwed into contact
with the top surface 33 of the insert 30. An appropriate driver
tool can be inserted through an access hole 48 in the handle 40 to
access the shaped socket 52 of the locking plug. For instance, if
the shaped socket 52 is a hex socket, a hex wrench could be
inserted through the access hole 48 in the handle 40 and into the
shaped socket 52 of the locking plug 50. The hex wrench could then
be used to drive the locking plug 50 along the internal threads 44
of the handle 40 so that the lower face of the locking plug is
firmly in contact with the upper face 33 of the insert 30. This
will fix the handle 40 with respect to the insert 30 and the shaft
22.
[0038] In the embodiment shown in FIG. 3A, the handle 40 has been
screwed almost all the way down onto the shaft to provided the
minimum combined length of the handle and the shaft.
[0039] When it is desirable to increase the combined length of the
handle and the shaft, the hex wrench could again be inserted
through the access hole 48 of the handle 40 and into the shaped
socket 52 of the locking plug. The hex wrench could then be used to
unscrew the locking plug away from the top surface 33 of insert 30.
This will free the handle with respect to the shaft. The handle
could then be unscrewed relative to the shaft to increase the
combined length of the handle and the shaft. When the desired
combined length is obtained, the hex wrench could then be used to
screw the locking plug back into contact with the top surface 33 of
the insert 30 to again fix the handle with respect to the
shaft.
[0040] The lower portion of the handle will preferably always
extend down over the working portions of the length adjusting
mechanism and surround the upper end of the shaft 22. The smooth
inner walls 46 of the handle 40 are configured to abut the upper
end of the shaft 22 to provide a smooth outward appearance. Because
the working portions of the length adjustment mechanism will be
completely contained within the handle, the golf club would be
indistinguishable from other ordinary clubs.
[0041] Because the handle 40 is rotated along threads on the insert
30, the golf club is adjustable to an almost infinite number of
different lengths between the minimum and maximum limits. The pitch
of the treads can be varied between a very fine pitch and a very
coarse pitch to control the amount that the length of the club
changes for each rotation of the handle with respect to the shaft.
In presently preferred embodiments, the thread pitch is relatively
fine so that the locking plug is as effective as possible in fixing
the handle with respect to the shaft.
[0042] A second embodiment of the length adjusting mechanism is
shown in FIGS. 4A and 4B. In this mechanism, the shaft 22, the
insert 30, and the handle 40 are very similar to the embodiment
shown in FIGS. 2, 3A and 3B. In this embodiment, however, external
threads 45 are also formed on the lower outer surface of the handle
40.
[0043] In addition, in this embodiment, a collar 70 is provided to
fix the handle 40 with respect to the shaft 22. The collar 70 has
interior threads 72 that are configured to cooperate with the
external threads 45 on the handle 40. Once the handle 40 has been
screwed onto the insert 30 and the shaft 22, to provide the club
with the desired overall length, the collar 70 is screwed onto the
threads 45 on the lower end of the handle 40. Screwing the collar
70 onto the lower portion of the handle 40 will compress the smooth
inner surface 46 of the collar against the upper end of the shaft
22 to fix the handle 40 with respect to the shaft 22.
[0044] In some embodiments of the invention, the inner surface 46
of the handle and the mating surface on the upper portion of the
shaft 22 can be custom tailored to help fix the handle 40 relative
to the shaft 22. For instance, the surfaces might be roughened so
that the compression provided by screwing the collar 70 onto the
handle 40 provides a great deal of friction between the handle 40
and the shaft 22. In other embodiments, one or both of the mating
surfaces may be formed of or covered with a material having a high
coefficient of friction.
[0045] In some embodiments of the invention, the lower portions of
the handle 40, which have the exterior threads 45, may be tapered
such that the exterior diameter of the handle increases from the
lower edge of the handle up to the top of the threaded section 45.
In this instance, as the collar 70 is screwed up the threaded
portion 45 of the handle, the lower portion of the handle 40 will
be forced against the shaft 22.
[0046] In other embodiments of the invention, the collar 70 may
have an internal threaded surface 72 which increases in diameter
from the lower side of the collar to the upper side. In this
instance, as the collar 70 is threaded onto the handle, the handle
will be forced farther and farther inward toward the shaft 22 the
higher the collar 70 is threaded up the handle 40.
[0047] FIGS. 5A, 5B, 6 and 7 show a third embodiment of the
invention. In this embodiment, the mechanism used to fix the handle
40 relative to the shaft 22 is a set screw.
[0048] FIG. 5A shows a side view of a shaft 22 and insert 30. Note,
this view is not presented in cross-section. A groove or keyway 36
is formed on the insert 30. The groove extends in the longitudinal
axial direction. FIG. 5B shows, which is a side view of the insert
30 shown in FIG. 5A, shows that the groove or keyway 36 extends
inward into the insert 30 in the radial direction. In other
embodiments of the invention which do not include an insert 30, and
which have the exterior threads formed directly on the upper end of
the shaft 22, the groove or keyway 36 would also be formed on the
upper end of the shaft 22.
[0049] In this embodiment, a handle substantially as shown in the
embodiment of FIGS. 2, 3A and 3B would be threaded down onto the
insert 30 and shaft 22 as shown in FIG. 6. In this embodiment,
however, a threaded fixation aperture passes through a sidewall of
the handle. A fastener, such as a set screw 47, would be screwed
into the fixation aperture, and then down into the groove or keyway
36 of the insert 30. FIG. 6 is a side view of the mechanism, with
the set screw 47 partially screwed into the fixation aperture. FIG.
7 is a cross-sectional view of the mechanism taken along section
line 7-7 of FIG. 6. In FIG. 7, the set screw 47 has been fully
screwed down into the fixation aperture, and into the groove 36 of
the insert 30.
[0050] In preferred embodiments of this form of the mechanism, a
recess 49 would be formed on the outer surface of the handle 40
where the fixation aperture is formed. The head of the set screw 47
would then sit in the recess 49 so that the set screw 47 does not
protrude above the outer surface of the handle.
[0051] When the user wants to adjust the length of a club having
the mechanism shown in FIGS. 5A, 5B, 6 and 7, the user would first
partially unscrew the set screw 47 from the handle 40 so that the
end of the set screw 47 rises above the level of the insert 30. The
handle 40 can then be rotated with respect to the shaft 22 to alter
the combined length of the shaft 22 and the handle 40. Then set
screw would then be tightened back into the handle so that the end
of the set screw 47 extends into the groove 36 of the insert to fix
the handle 40 with respect to the shaft 22.
[0052] In each of the embodiments described above, the exterior
surface of the handle may be configured as the grip of the golf
club. In other embodiments of the invention, a gripping material
could be applied to the exterior surface of the handle 40 to
provide a grip.
[0053] Also, in each of the embodiments of the invention, length
indicating marks 60 could be applied to the shaft 22 of a golf club
embodying the invention, as shown in FIGS. 8A-8C. As the handle is
screwed down over the upper end of the shaft 22, the handle 40
would cover some or all of the marks. For instance, when the handle
is positioned as shown in FIG. 8C, only the first three length
indication marks would be showing. When the handle is repositioned
to the location shown in FIG. 8B, the first six length indication
marks would be shown. When the handle is again repositioned to the
location shown in FIG. 8A, more of the length indication marks
would be showing.
[0054] In a typical set of golf clubs, the clubs are not all the
same length. The driver typically has the greatest length. The
woods then get smaller in length as the degree of loft, or club
face inclination increases. The irons are generally shorter than
all of the woods. The length of the irons also gets smaller as the
degree of loft, or club face inclination increases. For these
reasons, when a golfer purchases a set of adjustable length clubs,
the clubs should not all be adjusted to the same length.
[0055] By providing the clubs with length indication marks, all of
the clubs can be adjusted at the same time to the appropriate
length. A chart can be prepared and provided with the clubs to
indicate what length the clubs should have for a given golfer
height. When a child golfer has grown, and it becomes necessary to
adjust the length of his clubs, all the clubs could be adjusted to
have the same number of length indication marks showing. This will
ensure that all the clubs in the set can be easily adjusted to an
optimum length, even though no two clubs in the set will have the
same length.
[0056] When adjustable length clubs embodying the invention are
used for a child golfer, it is possible for the child to one, or at
most two sets of clubs from childhood to adulthood. Since it is
usually necessary for a child to use four or more sets of fixed
length clubs to cover the same period of time, this greatly reduces
the total cost of purchasing clubs over the period from childhood
to adulthood. Also, since only one or two sets must be purchased, a
consumer may be willing to spend more money on each set of
adjustable length clubs, which would allow the clubs to be made of
higher quality, more expensive materials. Further, because the
adjustable length clubs embodying the invention can be adjusted at
will to an almost infinite variety of different lengths, the child
can always be golfing with an optimum sized set of clubs.
[0057] The foregoing embodiments and advantages are merely
exemplary and are not to be construed as limiting the present
invention. The present teaching can be readily applied to devices
and implements other than golf clubs. The description of the
present invention is intended to be illustrative, and not to limit
the scope of the claims. Many alternatives, modifications, and
variations will be apparent to those skilled in the art. In the
claims, means-plus-function clauses are intended to cover the
structures described herein as performing the recited function and
not only structural equivalents but also equivalent structures. For
example, although a nail and a screw may not be structural
equivalents in that a nail employs a cylindrical surface to secure
wooden parts together, whereas a screw employs a helical surface,
in the environment of fastening wooden parts, a nail and a screw
may be equivalent structures.
* * * * *