U.S. patent application number 10/549457 was filed with the patent office on 2006-08-10 for putting stroke analyzer and putter for use therein.
Invention is credited to Daiichiro Suzuki, Toru Yamada.
Application Number | 20060177807 10/549457 |
Document ID | / |
Family ID | 34074138 |
Filed Date | 2006-08-10 |
United States Patent
Application |
20060177807 |
Kind Code |
A1 |
Yamada; Toru ; et
al. |
August 10, 2006 |
Putting stroke analyzer and putter for use therein
Abstract
The present invention is to provide a putting stroke analyzer,
and a putter for use therein, in which a signal generated in a
position detecting antenna through electromagnetic induction is
detected by stroking a putter having a head added with an LC
resonance circuit, i.e. electromagnetic resonators above position
detecting mats having a plurality of exciting coils also serving as
the position detecting antennas extending, respectively, in the X
axis direction and Y axis direction in order to grasp movement of
the putter head in the putting stroke of golf continuously with a
sufficient accuracy. It contributes to enhancement of skill of a
player oneself or guidance of the player and to selection of a
putter optimal to the player.
Inventors: |
Yamada; Toru; (YAMAGATA-SHI,
JP) ; Suzuki; Daiichiro; (Shizuoka, JP) |
Correspondence
Address: |
GRIFFIN & SZIPL, PC
SUITE PH-1
2300 NINTH STREET, SOUTH
ARLINGTON
VA
22204
US
|
Family ID: |
34074138 |
Appl. No.: |
10/549457 |
Filed: |
December 22, 2003 |
PCT Filed: |
December 22, 2003 |
PCT NO: |
PCT/JP03/16540 |
371 Date: |
September 14, 2005 |
Current U.S.
Class: |
434/252 |
Current CPC
Class: |
A63B 69/3676 20130101;
A63B 69/3614 20130101 |
Class at
Publication: |
434/252 |
International
Class: |
A63B 69/36 20060101
A63B069/36 |
Claims
1. A putting stroke analyzer wherein a signal generated in a
position detecting antenna is detected through electromagnetic
induction between exiting coils and electromagnetic resonators by
stroking a putter having a head having electromagnetic resonators
that is an LC resonance having an inductor and a capacitor, and
between the electromagnetic resonators and the position detecting
antenna.
2. A putting stroke analyzer in accordance with claim 1 wherein a
signal generated in a position detecting antenna is detected
individually through electromagnetic induction acted by each
electromagnetic resonator by stroking the putter added with one
electromagnetic resonator at a toe side (tip side viewed from a
player) of the head and one electromagnetic resonator at a heel
side (this side viewed from a player) of the head.
3. A putting stroke analyzer in accordance with claim 2 wherein a
signal generated in a position detecting antenna is detected
individually through electromagnetic induction acted by each
electromagnetic resonator, setting two pairs of independent
position detecting mat adjacently at the both sides of stroking
line of the head at the time of using said putter.
4. A putting stroke analyzer in accordance with claim 2 wherein a
signal generated in a position detecting antenna is detected
individually through electromagnetic induction acted by each
electromagnetic resonator by using a pair of mat to make the
exciting coils also serving as position detecting antennas work
separately at this side and that side of stroking line of head at
the time of using said putter.
5. A putter having the head added with the electromagnetic
induction in accordance with claim 1.
6. A putter in accordance with claim 5 wherein the electromagnetic
induction is removable.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to an apparatus to contribute
to enhancement of skill of a player oneself of guidance of the
player and to selection of a putter optimal to the player by
analyzing a putting stroke of golf, and a putter for use
therein.
BACKGROUND OF THE INVENTION
[0002] Especially, a skilled golf player makes much account of a
putting since it has an effect on the score. However there are a
few ranges to practice easily and there is no way to analyze and
evaluate the sensitive stroke objectively even if there is a range.
Therefore the only way to improve the putting skill is to practice
over and over again spending time and energy. On the other hand, it
is difficult for an instructor to give a proper advice based on
objective data.
[0003] One of inventors of the present invention is a professional
coach authorized by the Japan Driving Range and also prosecutes to
make putters to fit an individual player. He has provided handmade
putters which have all kinds of different elements respectively
such as shape, weight, length, lie angle (angle between ground and
shaft), loft angle ( an angle between sole and face of the putter),
goose angle (an angle between ground and bump), appearance of
putter face, an aiming line (a line to indicate aiming direction
marked on a putter head) to fit somatotypes, requests, images of a
variety of professional players.
[0004] In this case, the above putters provided to fit the
individual player are not always the best ones since there is no
way to analyze and evaluate the players' stroke accurately and
objectively.
[0005] Conventionally, the common way to judge the skill of putting
stroke was to judge from the actual rolling way of a ball on the
putting green of golf course or the training mat made of artificial
turf.
[0006] Recently, the unexamined utility model application
No.06-81567 discloses a training equipment to estimate the rolling
distance, and the unexamined patent application No.2000-102633
discloses a training equipment to estimate not only the rolling
distance but also the rolling direction, by detecting movement of
the ball rolling between two points using an optical sensor in
order to be able to practice at narrow area without checking the
rolling way of the ball to the end.
[0007] However these inventions are to judge putting condition by
checking the movement of the ball and they can not evaluate the
putting stroke itself to cause the movement of the ball.
[0008] The training equipments for evaluating the putting stroke by
detecting the movement of the putter head using the optical sensor
and the like are put on the market such as "Putting Checker" of
Miyamae incorporated (Higashi-Osaka city) and "Putting Machine" of
Sword Technica (Kawasaki city).
[0009] The former arranges plural pairs of some sensors put across
the training mat in the direction of the stroke to detect light
reflected from the putter head stroked on the mat to analyze and
indicate track of the putter head, slope of the aiming direction of
the putting face, head speed and the like by detection of light
reflected from each sensor and time difference of the reflected
light.
[0010] The latter detects laser light reflected from the putting
face by optical sensors to grasp movement of the putter head by
several pairs of magnetic sensors arranged on the training mat for
putting stroke to analyze and display slope of the aiming direction
of the face, the head speed and the like.
[0011] However the above equipments can only detect the movement of
the putter head roughly since they analyze data input from limited
number of sensors by a calculator to display the result and have
limited accuracy because the input data don't have continuity.
[0012] The sorts of data to be able to display as the analyzed
result and timing during the stroke to be able to display are
limited since the input data are limited. For example, in the case
to display the direction of the face, they display only at the
predetermined limited timing such as the direction at the time of
aiming or impacting.
[0013] In order to know and correct the putting stroke of a player
oneself as necessary to rise the probability to drop a ball in a
cup greatly, it is much effective to provide an apparatus to
measure and analyze, evaluate the putting stroke, namely the
direction of the face, the track of the head (including sweet spot
at the time of impact and shift in the both directions of toe (tip
side from the player's view)/heel (this side from one's view) of
hitting point during from the aiming decided by the player at the
beginning of the stroke, take away stroke at the time of prestroke,
forward stroke for hitting the ball, impact, to follow through
stroke after impact, and head speed, and display the result.
[0014] And also it is possible to give a proper advice based on the
objective data to improve the putting skill if the apparatus is
available to analyze and evaluate the putting stroke to display the
result with a sufficient accuracy.
[0015] Furthermore if there is such an apparatus at the golf shop,
it is very helpful to select a proper putter for a customer since
he or she can evaluate the putting stroke of oneself at the time of
using of the putter easily and objectively by stroking with the
putter using the apparatus.
[0016] The object of the present invention is to provide means to
be able to analyze and evaluate all kinds of data such as the
direction of the face, the track of the head, and the speed of the
head at any timing during stroke with a sufficient accuracy to meet
the need of the player by analyzing data to indicate the movement
of the putter head during the putting stroke continuously.
SUMMARY OF THE INVENTION
[0017] The present invention analyzes movement of the putter head
in the putting stroke of golf continuously with a sufficient
accuracy by using position detecting method through electromagnetic
induction.
[0018] First of all the position detecting method through
electromagnetic induction will be described.
[0019] On the position detecting mat, a plurality of exciting coils
X1, X2, X3 . . . , Xn extending in the X axis direction are
arranged in parallel horizontally, and also a plurality of exciting
coils Y1, Y2, Y3 . . . , Ym extending in the Y axis direction are
arranged in parallel horizontally, as shown on the FIG. 8. A
constant frequency signal is sent from an exciting and detecting
apparatus to these coils one and after.
[0020] On the other hand, electromagnetic resonators 24 which is an
LC resonance circuit combined capacitance with inductance selected
to resonate to the frequency are set on the side detected position,
on the putter head (not shown) in this case, so that the surface of
the inductor can parallel to the surface of the mat.
[0021] For example, once the signal is sent from the exciting and
detecting apparatus 35 to the coil X2, magnetic line of force that
the strength changes in response to the frequency generate in the
coil X2, and a part of the magnetic line of force pass through the
inductor of the electromagnetic resonators. The current having the
same frequency flows in the electromagnetic resonators according to
Faraday's law relating to the electromagnetic induction because the
magnetic line of force passing through changes in response to the
frequency. The coil X2 serves as an exciting coil in this case.
[0022] The current flowing in the electromagnetic resonators 24 is
larger if the electromagnetic resonators are close to the coil X2,
and they are smaller if they are far from that. Because the
magnetic line of force generated hardly ever pass through the
inductor of electromagnetic resonators since the magnetic line of
force generating from the coil X2 set horizontally faces to the
perpendicular direction approximately when the position of the
electromagnetic resonators deviates from the coil X2.
[0023] When the current flows in the electromagnetic resonators 24
through electromagnetic induction, the current generates the
magnetic line of force as well. The strength of the magnetic line
of force changes at the same frequency as the current flowing in
the electromagnetic resonators. The current having the same
frequency flows in the coil according to Faraday's law because the
magnetic line of force that the strength changes passes through the
coil arranged on the position detecting mat.
[0024] The coils on the position detecting mat serve as not only
exciting coils but also position detecting antennas. Namely, the
exciting and detecting apparatus 35 measure the current generated
through the electromagnetic induction in the coils Y1, Y2, Y3, . .
. Ym by current flowing the electromagnetic resonators as signals
one after another. Likewise, The signals excited in the coils Y1,
Y2, Y3, . . . Ym are larger if electromagnetic resonators 24 are
close to the coil, and they are smaller if they are far from that.
Because the magnetic line of force generated at the electromagnetic
resonators hardly ever pass through the coils since the magnetic
line of force generating from the inductor of electromagnetic
resonators set horizontally faces to the perpendicular direction
approximately when the position of the electromagnetic resonators
deviates from the coil.
[0025] Every time the exciting operation is repeated at X1, X2, X3,
one after another, the detection operation is repeated at Y1, Y2,
Y3, . . . one after another, and every time the exciting operation
is repeated at Y1, Y2, Y3, . . . one after another, the detection
operation is repeated at X1, X2, X3, . . . one after another.
[0026] The strength S of the detected signal indicates maximum Sa
at the position detecting antenna Xa proximate to the
electromagnetic resonators, and the strength of the detected signal
goes down such as Sa+1, Sa+2, . . . , or Sa-1, Sa-2, . . . as the
distance from the electromagnetic resonators is longer such as
Xa+1, Xa+2, . . . , or Xa-1, Xa-2, . . . . The point Xm that the
strength of signal is a maximum Sxm on a curve Cx tracing these
measure points is where the electromagnetic resonators exist.
[0027] Likewise, Ym can be sought as a maximum Sym on a curve Cy as
shown FIG. 9(b).
[0028] Accordingly, x-y coordinate including the electromagnetic
resonators can be easily obtained.
[0029] The present invention is an apparatus to detect a signal
generated in a position detecting antenna through electromagnetic
induction between an exciting coil generated by stroking a putter
having a head added with electromagnetic resonators of an LC
resonance circuit having inductance and capacitance and
electromagnetic resonators, and between electromagnetic resonators
and the position detecting antenna, above position detecting mats
having a plurality of exciting coils also serving as the position
detecting antenna extending, respectively, in X axis direction and
Y axis direction.
[0030] The player strokes a putter having a head partially added
with electromagnetic resonators above the position detecting mats
having exciting coils also serving as the position detecting
antennas.
[0031] It is not always required to put a golf ball on the position
detecting mat, and it is only required to mark the position of the
ball. Further means for indicating the direction of a cup position
for aiming will be required.
[0032] When the player strokes to the cup position assuming that
the mark on the position detecting mat is the golf ball, the x-y
coordinate having electromagnetic resonators added with the putter
is measured instantly and continuously by the position detecting
method using the above electromagnetic induction.
[0033] The apparatus analyzes the x-y coordinate on each measured
time and display the result by value or images to provide efficient
data for a player to aim enhancement of putting skill and a trainer
to coach for the enhancement, such as the track of patter head and
head speed in the stroke, and sweet spot at the time of impact and
shift in the both directions of toe/heel, rolling distance to be
able to estimate from head speed at the time of impact instantly
and with a sufficient accuracy. It can indicate valuation of the
putting stroke based on those data. It is very effective for
selecting the best putter for one to obtain these data instantly as
mentioned above.
[0034] The analyzing method can provide all kinds of data including
value of any timing in the stroke but not limited to the above data
to meet the player's need, since it is possible to grasp data
indicating movement of the putter head in the putting stroke by
using the position detecting method through electromagnetic
induction.
[0035] According to experiment using a mat that comprises exciting
coils also serving as the position detecting antennas to arrange
wires extending respectively in the X axis direction and Y axis
direction at 5 mm distance to connect as shown FIG. 8, it was easy
to detect position of electromagnetic resonators with accuracy
below 0.1 mm. The detecting speed was enough to grasp movement of
head in putting continuously since the position detecting can be
done instantly.
[0036] Furthermore, it is possible to detect position of
electromagnetic resonators added with the putter head when the
player strokes a putter on the mat commonly since it is possible to
detect the position even if the electromagnetic resonators locates
at 20 to 30 mm above the mat.
[0037] The electromagnetic resonators for use therein can be
installed at the normal putter head with little obstruction to
putting stroke because it can be configured to cylinder shape below
8mm diameter and 15mm height. And has proper size to install at the
putter head.
[0038] The present invention is the above apparatus to detect
signals generated in a position detecting antenna individually
through electromagnetic induction acted by each electromagnetic
resonator to analyze the putting stroke, using a putter added with
two electromagnetic resonators comprising one at toe side (tip side
viewed from a player) of the head and another at heel side (this
side of the head).
[0039] It is possible to analyze not only position of the whole
head but also an angle to the aiming direction of the head face
(including an angle of the face at the time of impact) continuously
with a sufficient accuracy by measuring and analyzing the x-y
coordinate of two electromagnetic resonators installed at the head
on each time individually. Of course it is easy to display an angle
of the face not only at the time of aiming and impacting but also
at any timing in the stroke in response to the player's need.
[0040] These are also useful data for a player aiming enhancement
of skill and a trainer coaching for the enhancement and very
helpful to select the best putter for oneself since the difference
between aiming line inscribed on the upper face of putter head to
indicate the direction and feeling of the player oneself having the
putter is clear.
[0041] Furthermore, the present invention is the above apparatus
characterized by detecting signals generated in a position
detecting antenna individually through electromagnetic induction
acted by each electromagnetic resonator, setting two pairs of
independent position detecting mat adjacently at the both sides of
stroking line of the head at the time of using a putter added with
one electromagnetic resonator on each side of toe and heel of the
head.
[0042] As mentioned above, the position detecting method through
electromagnetic induction detects a signal generated in a position
detecting antenna through electromagnetic induction between
exciting coils and electromagnetic resonators, and between the
electromagnetic resonators and the position detecting antenna to
measure x-y coordinate of the electromagnetic resonators.
Therefore, the above method sometimes can not grasp the x-y
coordinate with accuracy because of measurement by adding signals
acted by each electromagnetic resonator if two electromagnetic
resonators exciting at the same frequency are existed closely.
[0043] It causes a little damage if two electromagnetic resonators
separate from each other at a distance since magnetic line of force
generated from exciting coils and electromagnetic resonators faces
toward perpendicular direction.
[0044] In that case, it is better to detect signals generated in
the position detecting antenna individually through electromagnetic
induction acted by each electromagnetic resonator, setting two
pairs of independent position detecting mat adjacently at the both
of this side and that side viewed from a player of stroking line of
the head in order to prevent from disturbance by existence of other
electromagnetic resonator.
[0045] The electromagnetic resonator at the heel side is measured
on the position detecting mat at this side of stroking line since
two electromagnetic at the toe side and the heel side of putter
head resonators are set at a distance from each other.
[0046] The same effect as the above can be obtained by using a pair
of position detecting mat to make the exciting coils also serving
as position detecting antennas work separately at this side and
that side of stroking line of head instead of setting two pairs of
mats independently at the both sides of stroking line of the
head.
[0047] Namely, the same effect as the above case setting two pairs
of position detecting mats can be obtained if the exciting coils
also serving as the position detecting antennas in parallel to the
stroking line have two pairs of group at this side and that side of
the stroking line of the head and another group is not exciting
when one group is exciting or another group is controlled not to
detect by exciting and detecting apparatus when one group is
detecting.
[0048] It is possible to prevent from disturbance of measurement by
existence of another electromagnetic resonator to measure x-y
coordinate of two electromagnetic resonators with a sufficient
accuracy to analyze putting stroke with accuracy, even if any
methods are used.
[0049] The present invention is a putter added with electromagnetic
resonators combined with the above putting stroke analyzing
apparatus. The above putting stroke analyzing apparatus can act by
using the putter having a head added with electromagnetic
resonators.
[0050] The putter is preferable to able to remove the
electromagnetic resonators added in necessary.
[0051] The head added with electromagnetic resonators don't have
any effect on playing at the golf course. The player oneself
doesn't feel bad by the existence of the electromagnetic resonators
or the stranger doesn't have misgivings about effect on playing by
the existence, if the electromagnetic resonators are removable if
necessary.
BRIEF DESCRIPTION OF THE DRAWINGS
[0052] FIG. 1 is a whole view of constitution of preferred putting
stroking apparatus according to the present invention;
[0053] FIG. 2 is a enlarged view of the putter head part according
to the present invention;
[0054] FIG. 3 is a front view and a side view of the putter head
according to the present invention;
[0055] FIG. 4 is a view of the structure of a electromagnetic
resonator added to the putter head according to the embodiment of
the present invention;
[0056] FIG. 5 and FIG. 6 are respectively one example of display of
the putting stroke analyzing apparatus according to the present
invention;
[0057] FIG. 7 is a view for explaining connection between the
electromagnetic resonators added to the putter head, and sweet spot
and face of the head;
[0058] FIG. 8 and FIG. 9 are respectively a view for explaining the
position detecting method through electromagnetic induction;
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0059] With reference to the drawings the present invention will
now be described to be able to understand easily.
[0060] FIG. 1 shows a whole view of preferred constitution of the
putting stroking apparatus according to the present invention. The
player 1 takes address position on the training mat 3 set two pairs
of position detecting mats 3a, 3b having exciting coils also
serving as position detecting antenna with the putter 2 having a
head added with electromagnetic resonators.
[0061] There is a mark indicating position of a ball to be hit on
the training mat 3, and laser light 33 radiates from laser beam
radiating apparatus 32 and irradiates an object such as wall and
the like so that indication 34 can come out in the direction of a
cup for aiming.
[0062] Exciting and detecting apparatus 35a, 35b are set on the
position detecting mats 3a, 3b, and a constant frequency of signal
is sent to the exciting coils also serving as the position
detecting antennas (not shown but correspond to X1, X2, X3, . . .
Xn, and Y1, Y2, Y3, . . . Ym,) one after another, or signals
excited by the coils are detected one after another.
[0063] The detected signals are sent to a calculation 36 including
data memory means 36a, operation means 36b, input means 36c, and
display means 36d.
[0064] FIG. 2 is a enlarged view shown a part of a head 21 of a
putter 2 the player 1 hands. FIG. 3 shows a front view (a) and a
side view (b) of the head 21.
[0065] Two holes 22a, 22b are bored through toe side and heel side
of bottom of the head 21 respectively; electromagnetic resonators
24 shown on FIG. 4 can be received therein respectively.
[0066] An LC resonance circuit comprising an inductor 25a and a
capacitor 25b selected to resonate at a constant frequency is
included in the electromagnetic resonators 24. A magnetic member
25c is sometimes inserted into the inductor 25a because of
dimensional limitation of electromagnetic resonators and resonant
frequency. Generally, resin layer 25d coat the LC resonance circuit
constructed like this to protect and insulate from exterior.
[0067] The electromagnetic resonator 24a is inserted into a hole
22a of the toe side of a head 21 shown on FIG. 2 and the
electromagnetic resonator 24b is inserted into a hole 22a of the
heel side thereof to be fixed.
[0068] The player 1 takes address position to put the head 21 on
the mark 31 indicating position of the ball to stroke along the
aiming line 26 toward the indication 34 of the cup.
[0069] The electromagnetic resonators 24a don't deviate from the
position detecting mat 3a or the electromagnetic resonators 24b
don't deviate from the position detecting mat 3b, as long as the
player stroke naturally since the position detecting mat 3a is
arranged at that side of the stroking line viewed from the player
and the position detecting mat 3b is arranged at that side
thereof.
[0070] Furthermore, at the experiment using training mats set the
position detecting mats 3a and 3b at 10 mm distance, the position
detecting mat 3a could detect x-y coordinate of the electromagnetic
resonator 24a and the position detecting mat 3b could detect x-y
coordinate of the electromagnetic resonator 24b, without any effect
from other electromagnetic resonators.
[0071] Data sent from the exciting and detecting apparatuses 35a,
35b to calculator 36 are stored in the memory means 36a and
processed at operation means 36b to enhance putting skill of the
player oneself such as direction of the face 27, trace of the head
in the stroke, deviation between sweet spot 28 and toe/heel
direction of the actual hitting point at the time of impact, head
speed and the like. Or they are converted into very efficient data
to coach for enhancement to be displayed at display means 36d.
[0072] FIG. 5 illustrates one example of display by the display
means 36d. FIG. 6 illustrates the English version thereof.
[0073] These are examples indicating "result" of the whole putting
stroke, an angle of the face at the time of aiming, the deviation
between a sweet spot and a hitting point, head speed at the time of
impact, rolling distance and direction estimated from them. It is
possible to be processed by the operation means 36b to display a
lot of efficient data outside these data, since x-y coordinate on
each time of each electromagnetic resonator 24a, 24b is stored as
continuous data. It is also to display a habit of the player's
stroke.
[0074] Furthermore, two electromagnetic resonators 24a, 24b are set
at symmetric position of both sides of aiming line 26 and in
parallel to the face 27 at the putter head 21 illustrated in FIG. 2
and FIG. 3. Therefore, in this case, it is possible to work out the
deviation between the sweet spot and toe/heel direction of the
actual hitting point at the time of the head, if the deviation in
the perpendicular direction of stroke line of both electromagnetic
resonators is detected since sweet spot 28 of the head is located
at the same distance as two electromagnetic resonators, and also it
is possible to work out the direction of the face 27 in stroke, if
the difference of passing time in parallel to the stroke line of
both electromagnetic resonators is detected.
[0075] However, two electromagnetic resonators 24a, 24b can not
always be set at symmetric position of both sides of aiming line 26
and in parallel to the face 27.
[0076] In that case, the calculator 36 can analyze and display
movement of the putter head with accuracy by inputting positions of
two electromagnetic resonators 24a, 24b and the sweet spot,
relationship of direction of the face 27, distance La between
electromagnetic resonators 24a and sweet a spot 28, distance Lb
between the electromagnetic resonator 24b and the sweet spot 28, an
angle .alpha. between the face 27 and La direction, and an angle
.beta. between La direction and Lb direction by an input means 36c
beforehand.
[0077] Furthermore, it is possible to be done works by this input
means 36c such as inputting distance to the aiming cup, or setting
rolling speed on the putting green, or titling a player's name or
date and the like to stroke data.
[0078] Fig. (b) illustrates a electromagnetic resonator having an
external thread 25d around resin layer and a groove 25f to be able
to insert a screwdriver into a lower part, namely a part correspond
to bottom of the head. The electromagnetic resonators are removable
to the putter head quickly and easily if internal threads are made
to fit the external threads inside of holes 22a, 22b of the putter
head.
[0079] The head added with electromagnetic resonators don't have
any effect on playing at the golf course. The stranger doesn't have
misgivings about effect on playing by the electromagnetic
resonators, and they can be removed as soon as someone notices, if
they are removable easily as the above. They can be removed before
playing, if the player oneself doesn't feel bad by the existence of
the electromagnetic resonators at the time of stroke.
[0080] Cylindrical resin shaped in the same outline as FIG. 4(b)
can be inserted, if holes 22a, 22b bother after removing
electromagnetic resonators.
[0081] As the above, a putting stroke analyzer and a putter for use
therein is very effective as a training apparatus for putting, an
apparatus to coach therefore, and also an apparatus to help
selecting the best putter for the player.
* * * * *