CA2347193A1

CA2347193A1 - Golf putting practice device

Info

Publication number: CA2347193A1
Application number: CA002347193A
Authority: CA
Inventors: Bryan T.C. Bradbury
Original assignee: Croisiere SA
Current assignee: Croisiere SA
Priority date: 2001-05-09
Filing date: 2001-05-09
Publication date: 2002-11-09
Also published as: WO2002089928A1; US20020169029A1

Abstract

A portable golf putting training device used by golfers to improve their putting stroke comprising a flexible plastic sheet with a reflective layer and guide lines both parallel to and perpendicular to the intended path of the ball. The guide lines and the reflective surface provide feedback to the golfer during the stroke as to whether (a) the club face is square to the intended path; (b) the putter has been drawn back parallel to the intended path; (c) the backswing is slow and smooth; and (d) a long follow-through has been made.
Preferably the device is made of a clear acrylic material with a protected reflective layer in which the guide lines are cut. The sheet is oblong and provided with an end-to-end longitudinally oriented target line that bisects the sheet. A spot for mounting a golf ball is marked less than half-way along the target line as measured from the backswing end. The spacing between successive transverse guide lines increases as one progresses from the backswing end to the ball mounting spot. Thereafter from the ball mounting spot to the follow-through end, the transverse guide lines are uniformly spaced.

Description

G:\c\CSA01\61371 ca\Drafts\Specification.K.wpd GOLF PUTTING PRACTICE DEVICE
Field of the technology The present invention relates to a golf putting practice and training device.
Background of the Invention This invention relates to a golf putting training and practice device which is portable, simple to construct, and which allows a golfer to improve his putting stroke through feedback provided both at address and during the golf swing.
There are many ways to putt a golf ball and there is no absolutely correct way in which to do so. However, it is commonly accepted that most golfers can benefit from a set of simple reasonable guidelines as long as the golfers practise them and apply them consistently. This leads to a putting stroke that, with practice, holes more putts. For example, many golfers would agree that the following guidelines, consistently followed, will improve a golfer's putting stroke:
(1 ) Stand with your shoulders parallel to the desired line of the putt;

(2) Stand at a distance so that your head is directly over the ball;

(3) Hold the putter so that its sweet spot marker is immediately behind the ball with the putter's face perpendicular to both the playing surface and the desired line of putt;

(4) Draw the putter back smoothly and slowly;

(5) Hit smoothly through the ball so that the putter continues on the target line after impact with the ball; and (6) Follow through to impart a top spin roll to the ball.
These guidelines may be used as a practice drill by a golfer. In order to ingrain this form of swing so that the golfer can perform this without conscious intervention, one particular stroke must be repeated in the same way, many times. An example of a suitable training regime is one where the golfer repeats exactly the same swing 60 times a day for 60 days.
Once this form of stroke is learned, the golfer may use it with putts of different lengths by simply lengthening the backswing and increasing the club face speed at impact.
Note that during the training phase it is best that the practice putts be of the same length, both as to putting distance and as to distance to the cup.
A number of putting training devices, some with reflective planar surfaces, are known.
However, their effectiveness is limited as none provide adequate means by which the golfer may practice and learn a slow and steady backswing or an extended follow-through.
Additionally:
(1) US Patent 5,131,659 (Lindberg Jr., 1992) discloses a practice aid with indicia marked, preferably by a silk screening technique, on a reflective sheet. This aid:
(a) fails to teach any technique for ensuring that the putter's face is vertical and perpendicular to the target line at address; and (b) teaches an unreliable method for the golfer to keep the putter on the target line during the backswing by providing two parallel lines between which the golfer must keep the putter head (which must be of a matching size).
(2) US Patent 5,294,124 (Florian, 1994) discloses a practice mirror that teaches that the backswing and follow-through should follow the arcuate path made by four guide lines rather than a path which follows the target line, thus imparting spin to the ball and causing the ball to be more likely to drift off course.
(3) US Patent 5,362,057 (Arima, 1994) discloses a putting practice device that:
(a) uses side panels to constrain the putter to a recommended path on both the backswing and the follow-through. In one embodiment, the side panels may be adjusted between a small number of fixed positions. This may be problematic for the following reasons: If the gap between the putter head and the side panels is too small, the putter head may bump against one or other side panel making the task for the golfer too challenging. Alternatively, if the gap is too wide, the putter can waver further off course than is desirable.
(b) has a channel cut in the base plate so that the ball can remain on the underlying putting surface. Although this provides the truest roll for the ball, having the channel removes the opportunity of providing guide lines to assist with the follow-through.
A number of prior devices include curved or divergent lines or patterns that distract from the desired rectilinear motion of the putting stroke. Some include raised walls or other raised elements that also provide a distraction. None provide a simple device for adequately facilitating an accurately repeatable backswing, ball contact and follow-through.
Many devices disclosed in the prior art, provide indicia that are intended to make it possible for the golfer to calibrate the strength of his or her swing. The idea is that if the club head is pulled back further on the backswing greater potential energy will be converted to kinetic energy and the club head will move faster at impact and the ball will travel further.
Generally speaking, this is so. However, it is also possible for a golfer to gain club head speed by applying muscle power during the stroke. Unfortunately, this may lead to a less controlled stroke, as the muscles of the arms ,wrists and hands are called on to perform a more complex task (i.e., to simultaneously control the alignment of the club and to provide motive power).
Generally, this is considered to be an undesirable putting technique and prior art does little or nothing to teach how to avoid this.

Summary of the Invention The present invention is a device that a golfer can use as a putting practice aid to improve his or her putting stroke.
The device comprises a thin, flat, flexible reflective sheet, preferably oblong, on which are marked a number of guide lines. The golfer lines up the long axis of the device in the direction of the target and places a ball on the sheet at a marked mounting spot. The golfer can use the guide lines in conjunction with the reflective surface to practice a putting stroke.
All guide lines on the preferred embodiment are either parallel or perpendicular to the target line. The mounting spot is preferably somewhat closer to the backswing end of the sheet than it is to the follow-through end of the sheet.
The device enables a golfer to:
(1 ) check that the face of the putter is perpendicular to both the surface of the device and to the desired line of travel of the ball;
(2) check that the golfer's eyes are directly over the ball;
(3) make a smooth, controlled backswing that decelerates uniformly at the extreme of the backswing and which accelerates uniformly on the forward part of the swing;
and (4) deliver an extended follow-through which is more likely to impart top spin to the ball, thus improving the likelihood that the ball will stay on course.
The present invention is designed specifically to produce a smooth, accurate and repeatable putting stroke, one which avoids any jerkiness or misalignment of the club face.
The practice technique used preferably calls on the golfer to put to one side the speed factor during practice and repeatedly work on a single swing of a constant strength. This makes it possible for the golfer to work on developing a consistent uniform stroke with the aid of this invention. After sufficient practice, the golfer can then broaden the scope of the practice to putts of differing lengths by adjusting the stroking speed and the length of the backswing.
Summary of the Drawings Figure 1 is a plan view of the preferred embodiment of a putting trainer.
Figure 2 is a front elevation view of the putting trainer and an enlargement of one area of finer detail in the vicinity of one end of a cross line.
Figure 3 is a side elevation view of the putting trainer and an enlargement of the area in the vicinity of one end of the target line.
Figure 4 is a bottom view of the putting trainer.
Figure 5 is a sketch of a right-handed golfer towards the end of the follow-through of a putting stroke, using the putting trainer.
Description of the Preferred Embodiment Figure 1 shows a plan view of the preferred embodiment of a putting trainer.
Viewed from above, a putting trainer 1 is a reflective multilayered sheet, generally of rectangular shape with a long axis 2 and a short axis 3, with guide lines thereon as described below.
The sheet 1 comprises an upper transparent layer 11 of relatively hard but flexible plexiglass or transparent plastics material, a reflective coating 12 on its underside, and a protective bottom layer 13, as will be described in more detail below with reference to Figure 2.
The long axis 2 of the sheet 1 is aligned parallel to the desired path of the ball. The sheet 1 should be long enough to accommodate a full backswing and follow-through of an average golfer; the golfer is able to use the edge between the face and the sole of the club to keep the club face aligned parallel to the guide lines 7 (to be described below) throughout the complete backswing, putting stroke, and follow-through. In an exemplary embodiment, the putting trainer 1 is approximately 1 m (39 ") long which is sufficient to allow golfers to practice a wide range of lengths of putt with a full backswing and follow-through. The short axis 3 is aligned generally parallel to the golfer's feet which are shown schematically in dashed lines as 4 (left foot) and 5 (right foot), for a right-handed golfer. The width of the putting trainer 1 should be small enough so that, in a comfortable stance, the golfer's toes do not overlap the putting trainer 1. In an exemplary embodiment, the putting trainer 1 is approximately 18 cm (7 ") wide.
A right-handed golfer stands as schematically shown by the footprints 4 and 5 in Figure 1 with the backswing end 9 on his right and the follow-through end 10 on his left.
Optionally, the corners of the sheet 1 may be slightly rounded to avoid chipping or injury during handling. The putting trainer presents a flat, generally mirrored surface on which a number of guide lines to be described below and a mounting spot 8 are visible. The putting trainer has:
(1) one guide line 6 running parallel to the long axis for the length of the sheet 1 and bisecting the sheet 1 longitudinally (the "target line"); and (2) a plurality of transverse guide lines 7 (the "cross lines", only three of which are labelled in Figure 1 ) running parallel to the short axis and perpendicular to the target line, each extending across the entire width of the sheet 1, the guide lines 7 being spaced along the length of the sheet 1 in the manner further described below.
The mounting point 8 is marked as a distinctive point where the golfer places the ball (not shown) on the putting trainer 1. The mounting spot 8 should be as small as possible so as not to distract the golfer during the swing but yet be large enough and of sufficient contrast to the background to be seen easily by a standing golfer. The mounting spot 8 may suitably be shaped and coloured in a variety of ways. In an exemplary embodiment, the mounting spot 8 is a yellow circle of approximately 0.25 cm (0.1 ") diameter. It may be formed on the underside of the sheet 1 by placing a drop of coloured paint at the intersection of the target line and a selected cross line.

In the preferred embodiment, the putting trainer is not symmetric along the long axis about the mounting spot. Figure 1 shows a backswing end 9 and a follow-through end 10. The length from the mounting spot to the follow-through end 10 is greater than the length from the mounting spot to the backswing end 9.
A left-handed golfer, whose footprints are not shown, stands on the other side of the putter trainer 1 with the backswing end 9 on his left and the follow-through end 10 on his right.
Figure 2 shows a front elevation of the putting trainer 1 and an enlargement of one area of finer detail. The rear elevation is identical, save for the orientation of the distribution pattern of the ends of the cross lines 7, whose spacing invariably increases from the backswing end 9 to the mounting spot 8 and thereafter is uniform from the mounting spot 8 through to the follow-through end 10. The putting trainer 1 is made as a sheet of a transparent flexible material 11 with a reflective layer 12 protected by a durable plastic coating 13, which is widely available commercially. An acrylic mirror product made by Plaskolite Inc. of Columbus, Ohio is suitable for the purpose. The putting trainer 1 has a flat upper surface and is of a generally uniform thickness. A golf ball can roll on the smooth surface to the follow-through end 10 where it drops to the surface underlying the putter trainer. As long as the drop is small, experience with the putting trainer shows that the effect of the drop on the path of the golf ball is negligible. However, optionally, the putting trainer may be bevelled at the follow-through end 10 to reduce the abruptness of the drop from the upper surface to the surface underlying the putter trainer. The thickness of the material is selected to balance the preference for a thinner product which gives a smaller drop at the follow-through end and a greater flexibility (and thus is better able to conform to the underlying surface) against the preference for a thicker product which is stronger. For the acrylic mirror product made by Plaskolite Inc., a thickness of 3 mm (1/8 ") is suitable.
The reflective layer 12 is of a conventional composition and has a mirrored surface reflecting upwardly which is adhered to the bottom surface of the putting trainer by conventional means and which is protected by a durable plastic coating 13. In the preferred embodiment, the target line 6 and the cross lines 7 shown in Figure 1 are formed by making channels 14 through the plastic coating 13, the reflective layer 12 and a portion of the transparent sheet 11 with a saw blade or a knife, by etching, chemical solvents or by other conventional means, so that sufficient material is removed from the plastic coating 13 and the reflective material 12 to make the channels distinctly visible from above. The width of the channels 14 is not critical but should be sufficient so that the target line 6 and cross lines 7 are easily visible to a golfer whose head is as much as 2 m (6 ') above the upper surface of the putting trainer 1. In an exemplary embodiment, a channel width of 2 mm (1/12 ") is found to be suitable. Figure 2 shows an enlargement of the front view of one cross line 7 formed as a channel 14 in the reflective layer 12 and plastic coating 13. Optionally, the areas of the reflective layer 12 from which reflective material have been removed may be painted or coated to improve their visibility.
In the preferred embodiment, the sheet 1 is first manufactured with three layers and channels 14 are cut as described above. However, other suitable manufacturing methods may be followed. For example, the target line 6 and the cross lines 7 may be:
(1) applied with adhesive as distinctive strips of contrasting material to the lower layer of the transparent sheet 11 prior to the application of the reflective layer 12 and the plastic coating 13; or (2) applied with opaque paint to the lower layer of the transparent sheet 11 prior to the application of the reflective layer 12 and the plastic coating 13.
Alternatively, the reflective layer 12 may first be adhered to the lower surface of the transparent sheet 11 and the target line 6 and the cross lines 7 formed, prior to the application of the plastic coating 13, by ablating portions of the reflective material 12 and applying opaque paint to form a suitably visible pattern of lines.
Figure 3 is an elevation view of the backswing end 9 and an enlargement of the area in the vicinity of the target line 6. The elevation from the follow-through end 10 is identical. This elevation shows the transparent acrylic material 11 with affixed reflective layer 12, protective plastic coating 13 and a channel 14 cut to make the target line 6.

Figure 4 is a bottom view of the putting trainer 1. This bottom surface of the putting trainer has a plastic coating 13 which protects the reflective material (not shown) and in which are cut the channels that make the target line 6 and the cross lines 7. In the preferred embodiment, the mounting spot 8 is made by painting a small, approximately circular area at the intersection of the target line and the line of address.
Figure 5 shows a sketch of a right-handed golfer 15 in the position he would assume at the end of the follow-through of his putting stroke using the putting trainer 1.
The location of the mounting spot 8 and the cross lines 7 is determined as follows:
( 1 ) A selection is made for the location of the mounting spot 8 along the length of the target line 6. This preferably is in the region between one half and three quarters of the length of the putting trainer as measured from the follow-through end 10. In the preferred embodiment, the mounting spot 8 is located at a point approximately 60-70% of the way along the target line 6 as measured from the follow-through end 10. While the preferred location of the mounting spot 8 is within the designer's discretion, the design decision to provide in the preferred embodiment more trainer length for observing the golfer's follow-through relative to the backswing reflects the importance of the follow-through part of the swing.
(2) Once the location of the mounting spot 8 is chosen, the cross line 16 is made through the centre of the mounting spot 8 (the "line of address");
(3) A set of evenly spaced cross lines 7 are made between the mounting spot 8 and the follow-through end 10 so that they are between about two and twenty in number.
In an exemplary 1 m-length embodiment, there are five such cross lines 7 which, together with the line of address 16 and the follow-through end 10, mark out six discrete reflective regions of equal size each of which is divided centrally into two parts by the target line 6;

(4) One cross line 7 is made towards the backswing end 9 and separated from the line of address 16 by the same width as that used to space out the cross lines 7 made on the side of the mounting spot 8 towards the follow-through end 10.
(5) Additional cross lines 7 are added between the line described in the previous paragraph and the backswing end 9 of the putting trainer 1 so that each line is spaced from its predecessor by a successively narrower gap.
In one embodiment of the invention, the spacing of the additional cross lines 7 is made so that the ratio of the distance from that cross line to its successor (or the edge at the backswing end 9 for the last cross line) is a fixed ratio, less than 1 and greater than zero, of the distance from that cross line to its predecessor. In the preferred embodiment of the invention, this ratio is selected to be between 0.7 and 0.9.
In an alternative embodiment of the invention, the values for the ratio are drawn from a table, such values based on feedback provided by golfers as to their subjective experiences.
One or more tables can be prepared from guidance provided by skilled golfers and used as models for preparing the guide line spacing. Ultimately, an empirical approach is best taken to guide line spacing selection and to dimensional choices generally.
The putting trainer 1 is designed to produce a simple putting stroke that produces few errors and provides the assurance of a consistent and repeatable stroke.
Ideally the stroke has a slow and smooth backswing without any jerking, a smooth forward motion, a square impact so that the desired path of the golf ball is orthogonal to the club face and a long follow-through with the putter continuing in contact with the ball so as to impart top spin which assists in keeping the ball on track. A golfer using the putting trainer employs the following steps to improve his or her putting stroke:
(1 ) The golfer places the putting trainer 1 on the ground or on a surface indoors so that the target line 6 points along the path on which the golfer intends to hit the ball.
(2) The golfer addresses the ball:

(a) the golfer places the tips of his or her shoes equidistant from the edge of the putting trainer;
(b) as measured by an imaginary line through his or her shoulders, the golfer stands parallel to the target line;
(c) preferably, the golfer stands with his or her dominant eye exactly over the ball, the dominant eye being determined as follows:
(i) the golfer stands over the putting trainer so that the mounting spot appears in the golfer's reflection equally between the eyes;
(ii) the golfer, in turn and one at a time, closes each eye and observes the lateral shift of the image of the mounting spot;
(iii) the dominant eye is selected as the open eye which produces the smallest lateral shift.
(d) should the golfer choose not to determine his or her dominant eye, the golfer should stand with the mounting spot appearing in the golfer's reflection equally between the eyes.
(d) the golfer places the club face just behind the ball with the putter's sweetspot marker on the target line 6 and directly behind the centre of the ball.
(3) The golfer makes the club face vertical by tilting the club along the target line 6 until the club face cannot be seen either directly or as a reflection in the putting trainer 1.
(4) The golfer makes the club face parallel to the line of address 16 by rotating the putter handle until the bottom edge of the club face is parallel with the line of address 16.
(5) The golfer focuses on the ball resting at the mounting point 8 and does not move his or her eyes from that point throughout the stroke.
(6) The golfer makes a slow backswing keeping the sweet spot marker directly above the target line 6 and the putter face perpendicular to the target line 6 throughout the backswing by checking the reflection of the putter face against the cross lines 7.

As the putter is drawn back, the cross lines 7 on the backswing side appear underneath the club face and are visible in the golfer's peripheral vision. If the putter is slowed smoothly the lines appear at a uniform rate. If the backswing is not slowed smoothly or is abbreviated then the cross lines do not appear at a uniform rate. This provides a clear visual signal to a golfer whether his putting stroke is as recommended.
(7) When the farthest point of the backswing is reached, the forward swing and follow-through are commenced. Throughout the forward swing and follow-through, the golfer keeps the putter's sweet spot marker directly above the target line 6 and the putter's face should remain square to the target line 6, this being confirmed by the reflection of the leading edge of the putter face being maintained parallel to the cross lines on both the forward swing and the follow-through.
(8) At the end of the follow-through, the golfer holds his or her position for a few moments to get the "feel" of the position.
(9) The golfer repeats this practice stroke slowly several times to imprint in muscle memory the pressures in the hands, wrists, arms and shoulders required to keep the putter's sweet spot and face on the target line 6 and square to the target line 6 throughout the putting stroke.

(10) Once a golfer has the feel of this putting stroke, the speed of the stroke can be varied for putts of various lengths.
The scope of the invention is not limited to the specific embodiments illustrated and described herein but is governed by the appended claims.

Claims

1. A golf putting training and practice aid comprising a transparent, generally planar sheet intended to be laid flat on the ground or indoors with a lower surface facing towards the supporting ground and an upper surface facing away from the supporting ground, and being reflective from above so that light passing through the sheet from above is reflected upwards and having a long axis and a short axis on which are marked guide lines and a mounting spot for a golf ball, all visible from above the upper surface of the device, such guidelines comprising:
(a) a target line running the length of the long axis, located parallel to the long axis and bisecting the short axis so that the visible lines and divided areas are symmetrical about the target line;
(b) a line of address running completely across the sheet, located parallel to the short axis and perpendicular to the long axis, such line of address dividing the long axis into two parts, a backswing side to the right for a right-handed golfer and a follow-through side to the left for a right-handed golfer;
(c) a plurality of cross lines running completely across the sheet and parallel to the line of address located so that the spacing of the cross lines on the follow-through side is uniform and the spacing of the cross lines on the backswing side are successively narrower as measured away from the line of address; and (d) a mounting spot located at the intersection of the target line and the line of address.

2. The device of claim 1 wherein the sheet is rectangular and all guide lines and any other linear indicia on the sheet are selected to be parallel either to the line of address or to the target line.

3. The device of claim 2 wherein the reflective material is disposed on the lower surface of the sheet and is covered with a protective plastic coating.

4. The device of claim 3 wherein the guide lines are formed on the underside of the sheet and are clearly visible from above the sheet.

5. The device of claim 4 wherein the target line and the longitudinal edges of the sheet are the only visible lines of the device having longitudinal extension.

6. The device of claim 5 wherein the line of address, cross lines and the end edges of the sheet are the only visible lines of the device having transverse extension.

7. The device of claim 1 wherein the margin at the follow-through end thereof is bevelled.

8. The device of claim 1 wherein the mounting spot is located approximately 60-70% of the way along the target line as measured from the edge at the follow-through side.

9. The device of claim 8 wherein the mounting spot is formed on the underside of the sheet with paint applied at the intersection of the target line and the line of address.

10. The device of claim 1 wherein the ratio of the spacing of successive cross lines on the backswing side proceeding from the line of address to the backswing end is approximately constant and less than 1.

11. The device of claim 10 wherein the ratio is selected to be between 0.7 and 0.9.

12. The device of claim 10 wherein the ratio is variable and the values used for the ratio are drawn from a predetermined table.

13. The device of claim 6, wherein the length of the sheet is selected to coincide approximately with the length of an average golfer's backswing and follow-through.

14 14. The device of claim 6, wherein the length of the sheet is approximately 1 m.