Source: http://www.google.com/patents/US3680860?dq=5,815,794
Timestamp: 2017-08-22 09:48:37
Document Index: 256475532

Matched Legal Cases: ['art 30', 'art 30', 'art 52', 'art 52', 'art 52', 'art.\n1']

Patent US3680860 - Method of fitting golfer with putter and improving putting accuracy - Google Patents
When putting a golf ball with a putter having aiming indicia on the upper surface of the club head, a golfer may fail to accurately aim said indicia along a straight line path to a predetermined putting target because of an inherent sighting error which is personal to each individual golfer. The extent...http://www.google.com/patents/US3680860?utm_source=gb-gplus-sharePatent US3680860 - Method of fitting golfer with putter and improving putting accuracy
Publication number US3680860 A
Publication number US 3680860 A, US 3680860A, US-A-3680860, US3680860 A, US3680860A
Inventors Elkins Vance V Jr
Original Assignee Elkins Vance V Jr
Patent Citations (9), Referenced by (34), Classifications (8), Legal Events (2)
Method of fitting golfer with putter and improving putting accuracy
US 3680860 A
When putting a golf ball with a putter having aiming indicia on the upper surface of the club head, a golfer may fail to accurately aim said indicia along a straight line path to a predetermined putting target because of an inherent sighting error which is personal to each individual golfer. The extent of the sighting error is not the same for all individuals and it may be either to the left or to the right of the putting target, thereby causing the individual to miss a high percentage of putts. When an individual's inherent sighting error is measured and the individual's putting club is provided with a properly inclined sighting error correction line, the individual may thereafter aim the personalized correction line at a desired target while executing a putting stroke and, thereby, incidentally cause the striking face of the putting club to be properly maintained. An individual's inherent sighting error may be measured by noting the extent of the individual's error in attempting to aim a sighting line, located in the vicinity of the usual golf ball position, at a distant target. The sighting line may be provided either on a reversible motor-driven disc operated by foot-controlled push buttons, on a piece of cardboard having an irregular shape, or on the upper surface of the head of a golf putting club. The extent of deviation from an accurate aim may be determined by placing a scaled chart behind the putting target and noting where an extension of the aimed sight line meets the chart. The sight line may be extended to the chart in various ways which include stretching a length of string along the sight line to the chart, by using apparatus which reflects a beam of light from a mirror to the chart, or by moving behind the aimed sighting line and looking along its length to see where on the chart it is aimed. When a golf putting club has been personalized for a particular sighting error, the nature and extent of that error may be indicated on the club by suitable markings provided either on the end of the club handle or on the sole of the club head
United States Patent Elkins, Jr.
[15] 3,680,860 45] Aug, 1,1972
[54] METHOD OF FITTING GOLFER WITH PUTTER AND IMPROVING PUTTING ACCURACY [72] Inventor: Vance V. Elkins, Jr., 42 Hampton Drive, Freehold, NJ. 07728 [22] Filed: June 25, 1971 [21] Appl. N0.: 156,904
Y [52] U.S. Cl. ..273/32 R, 273/183 D, 273/164,
273/8l.4, 273/167 R, 33/46 G, 29/407 [51] Int. .Cl. ...A63b 69/36, A63b 53/00, A63b 53/04 [58] Field of Search ..273/163, 164, 183, 186, 32',
Primary Examiner-George J. Marlo Attorney-Allan Ratner et a1.
[5 7 ABSTRACT When putting a golf ball with a putter having aiming indicia on the upper surface of the club head, a golfer m fail to atel im saiqimiisiaal s 3 218 31 line path to a predetermined putting target because of an inherent sighting error which is personal to each individual golfer. The extent of the sighting error is not the same for all individuals and it may be either to the left or to the right of the putting target, thereby causing the individual to miss a high percentage of putts. When an individuals inherent sighting error is measured and the individuals putting club is provided with a properly inclined sighting error correction line, the individual may thereafter aim the personalized correction line at a desired target while executing a putting stroke and, thereby, incidentally cause the striking face of the putting club to be properly maintained. An individuals inherent sighting error may be measured by noting the extent of the individuals error in attempting to aim a sighting line, located in the vicinity of the usual golf ball position, at a distant target. The sighting line may be provided either on a reversible motor-driven disc operated by foot-controlled push buttons, on a piece of cardboard having an irregular shape, or on the upper surface of the head of a golf putting club. The extent of deviation from an accurate aim may be determined by placing a scaled chart behind the putting target and noting where an extension of the aimed sight line meets the chart. The sight line may be extended to the chart in various ways which include stretching a length of string along the sight line to the chart, by using apparatus which reflects a beam of light from a mirror to the chart, or by moving behind the aimed sighting line and looking it its 1e h t see wh re on the chart i is aimed. e n a goli putt ing club has been personalized for a particular sighting error, the nature and extent of that error may be indicated on the club by suitable markings provided either on the end of the club handle or on the sole of the club head 12 Claims, 5 Drawing Figures METHOD OF FITTING GOLFER WITH PU'I'IER AND IMPROVING PUTTING ACCURACY BACKGROUND OF THE INVENTION 1. Field of the Invention 5 This invention relates to a method of improving the art of putting a golf ball accurately.
2. Prior Art Putters and other golf clubs have been known in the prior art to have alignment lines or other sighting instructed to view the alignment line and then draw an imaginary extension from that alignment line through the center of the ball to the target. He would then attempt to hit the ball with a true linear stroke exactly in the direction of the alignment line toward the target.
In using prior alignment lines with a sloped putting green, the golfer may select a point to one side of the hole and then by viewing the alignment line, he golfer attempts to putt toward that point. The slope of the green should then cause the ball to follow a curved path away from the point and into the target hole.
Other sighting marks have also been used for another purpose which is to indicate a proper position or spot on the club face to hit the ball. When the ball is hit at this spoton the club face the best possible stroke has been made for a-sweet spot hit.
Prior alignment lines have left much to be desired'in that when a golfer in an address stance used the line to indicate a true line from ball to target, he would in reality be following an incorrect line. What was not known and taken into accountwas the personal and inherent sighting error where each individual has his own sighting error. Individuals see things differently than they actually are when addressing a ball. Fore example, a right handed golfer may see the target at a particular angular sighting error to the right of where it actually is. Thus, prior alignment lines made no correction for an individuals sighting error.
Not only did prior alignment lines not aid the individual golfer, but they had the harmful effect in directing golfers to swing along an incorrect path. The golfer learns by practicing that in order to reach the target while following the alignment line, he must build in subconscious and subtle corrective movements from a true linear stroke. In this way, he subconsciously corrects for his unperceived sighting eye error.
His corrective movements may comprise one or more of the following. He may swing across the ball pulling it or pushing it back to where the target actually is in order to put the ball in the cup. Another subconscious corrective movement may be to rotate the club head in the course of the stroke from an open to a closed position. These subconscious corrective movements from the true linear stroke are very complex and have been found in practice to be extremely hard to reproduce. This difficulty in reproducibility may be seen, for example, in that even professional golfers miss 45 percent of their 6 foot putts although only 10 percent of these missed putts can be attributed to randomness of the green or incorrect distance judgment as set forth in a text by Cochran and Stobles, The Search for pp. 137 and 189, Tables 21 :2 and 29:4.
This text describes experiments with a perfect putting machine on average putting greens. It has been experimentally found that even with a perfect machine, as the putting distance increases, there is a higher percentage of putts missed as a result of the randomness of the putting surfaces. The level of skills of professional and amateur golfers is given in the text.
There is a substantial difference between the skills of golfers and the perfect putting machine and these differences are attributed to basic problems of the golfer. In the longer putts, the errors are equally attributable to errors in direction and errors in distance measurement. However, in shorter putts, such as 10 feet or less, errors in distance are negligible with the major error being caused by error in alignment and/or direction of stroke. The foregoing is seen in the following table which is a combined'and simplified form of the above cited Tables in the text.
It will be understood from the above that golfers miss a high percentage of short putts since they are effectively unable to coordinate their sighting and stroke. Thus, with any of the prior putters, even the professional golfer is unable to putt consistently and accurately.
SUMMARY OF THE INVENTION An individuals sighting error is measured by first rotating a sight line about a point until to the individuals view, it appears that the sight line is pointed directly at the target. The sighting error is then detected (a) as an angle between (i) a true line formed between the point and the target and (iii) a projected extension of the sight line. This error corresponds to a directional deviation to the left or right of the true line by the sight line extension.
After his sighting error is determined, the individual uses a putter having stripe-like indicia which extends at an angle relative to an imaginary vertical plane corresponding to the sighting error angle. The golfer first positions the putter rearwardly of a golf ball so that it appears that the indicia is pointed in the direction of his target. The golfer then moves the putter rearwardly and forwardly while attempting to maintain the indicia apparently pointed generally in the direction of his target just prior to striking the golf ball. BRIEF DESCRIP- TION OF THE DRAWINGS FIG. 1 illustrates in simplified form a top view of a system and method for measuring an individuals sighting error according to the invention;
FIG. 2 illustrates in simplified form a top view of another embodiment of the sighting error measuring system and method according to the invention;
FIG. 3 illustrates a top view of a putter which is provided to compensate for the individuals sighting error in FIG. 1;
FIG. 4 illustrates in more detail a perspective view of the putter of FIG. 3 with a different correction line; and
FIG. 5 is a top view of a putter showing a further embodiment of the invention.
Referring now to FIG. 1, there is shown the manner in which the sighting error of an individual may be measured. While the measuring system and method shown in FIG. 1 is directed to golfers, it will be understood that this system and method may be used for measuring sighting errors as defined herein, for any purpose. An individual assumes his usual and normal golf ball putting address stance as shown in which he attempts to align himself in front of a point 16 representing a golf ball. The individual golfer views a target 11, which for example, may be a light object in q dark background. Target 11 may be about the size of a golf ball so that it appears to the golfer as a point target. In a typical example, target 11 may be approximately feet from point 16; indicated in FIG. 1 as distance B.
The individual in assuming the normal putting address stance lines himself up square with his feet and body with both feet being on the same side of a true line 28 between point 16 and target 11. It is then important that the individual have his head and eyes in the position he would normally use to judge his line of sight to target 11. He places his arms behind his back to eliminate any corrections he may make by swinging his arms in a practice stroke. It is helpful to eliminate this feel to obtain accurate measurement of the sighting error.
Point 16 is at the axis of a dark heavy sight line 12 on a circular disc 215 which is rotated by a reversible motor 14. Push button switches and 21 may be provided respectively under the left and right foot of golfer 10. Actuation of switch 20 causes a slow clockwise rotation of disc 15 while actuation of switch 21 causes a slow counterclockwise rotation of disc 15.
As shown in FIG. 1, a true line 28 extends as a straight line between point 16 and target 11. From his normal stance, golfer 10 visually sights along sight line 12 to target 11. Golfer l0 actuates switches 20 and 21 until he believes sight line 12 is pointed at and is aligned with target 11. The actual position of line 12 in a typical example is as shown in FIG. 1. Sight line extension 24 is the imaginary projected extension of line 12 and forms with true line 28 a sighting error angle 34 to the right of line 28. It will now be understood that individual 10 by squaring himself has assumed an address stance in which the plane formed by the front of his body is substantially parallel to line 24.
In order to automatically measure the sighting error as a slight angle and as a directional deviation to the left or right of true line 28, a collimated light source 25 is then energized. Source 25 directs a beam of collimated light over target 1], along line 28 and over point 16 to a mirror 27. Mirror 27 is mounted on a support 27a secured to disc 15 as shown with the reflecting surface of the mirror being normal to sight line 12.
The collimated light is reflected along line 26 and forms a shining spot on chart at indication 2R. Chart 30 is directly behind source 25. Reflected line 26 is not coincident with sight line extension 24 for the following reasons. The light from source 25 is reflected by mirror 27 to form line 26 at an angle with the true line 28 equal to the sum of the angle of incidence and the angle of reflection which is approximately equal to twice the value of angle 34. Therefore, chart 30 which is normal to line 28 is scaled accordingly. With the sighting error being measured for golfer 10, he may now be provided with a club having a 2R (2 to the right of line 28) sighting error correction line or stripelike indicia as will later be described in detail.
In an example, the elements may have the following values:
Disc 15 lfoot diameter Mirror 27 1 inch square Light beam 250 2 inch diameter Thus, it will be understood that FIG. 1 is out of proportion with the actual values of angles 34, 35, mirror 27, distance B, etc. and has been drawn in this way solely for the purpose of simplifying explanation.
In another embodiment, golfer 10a stands before an irregular shaped piece of cardboard 40 on which is drawn a sight line 41 and visually sights from a point 42 on sight line 41 to a target 43. True line 39 extends between 42 and 43. Board 40 is rotated or moved about point 42 preferably by another person until to the individuals visual observation, it appears that the sight line extension 44 is pointed directly at target 43.
In order to calculate the sighting error a chart 52 is laid normal to true line 39. A string is stretched from point 50 (to take advantage of the entire length of line 41) along sight line 41 and extension 44 until it crosses chart 52 at point 54. Sighting error angle 47 is calculated by using the formula of the tangent of the angle is equal to distance A as shown divided by distance B. It will be understood that for ease in calculation charts may be made using as a basis a fixed distance B and plotting a scale on chart 52.
It will be understood that several measurements of golfer 10 may be made and the statistical average of his sighting error calculated. The reason for such a statistical average is that individuals vary in their testing consistency. Some individuals are very consistent while others give variable measurements over several tests. In some cases of nonconsistent measurements, it is helpful to cover the nondominant eye of the individual while taking the measurements. Such individuals may have a variable ability to fuse. Thus, by closing'the nondominant eye, the individual no longer has to fuse his two eyes together to scan line 41.
Referring now to FIG. 3, there is shown a golf club 100, which in this embodiment is a golf putter, having a sighting error correction stripe-like indicia or line 105. Correction line 105, visible to golfer 10b in his ball address stance, corrects for a 2R sighting error as shown in FIG. 1. This 2R sighting error is indicated by indicia notation 108 located on the bottom face of the club. Line 105 passes through the geometrical center 105a of club 100. Imaginary line 109 is normal to club face 110, also passes through center 105a and forms an angle 102 with line 105 equal to sighting error angle 34, FIG. 1. Angle 102 may also be expressed as a slight angle between line 105 and an imaginary vertical plan extending normal to club face 110.
As shown, the projected extension of line 109 is true line 112. To the right of true line 112, extension line 106 is formed as the projected imaginary extension of correction line 105. In this manner, there is formed a 5 2R sighting error correction which is personal to individual golfer 10.
Parallel to imaginary line 109 and perpendicular to club face 110 are edge lines 115-116 with the band area 120 between these lines being finished in a contrasting color to the remaining top visible face or upper surface 125 of club 100. Line 105 is preferably finished in a contrasting dark color with respect to area 120 so that line 105 is highly visible.
Golfer l assumes a golf stance next to golf ball 122 and positions club 100 so that line 105 and its extension 106 appearto him to be pointed directly at an actual target hole. 135. For the reasons previously described, lines 105 and 106 will actually be pointed at a visualized target hole 136. Thus, golfer has squared himself with lines 105 and 106 and band 120 is now pointed directly at the hole with lines 115-116 being parallel 'to true line 112. Further, club face 110 is aimed directly-at the actual target hole 135, i.e., face 110 is normal to true line 112.
The golfer now focuses himself only onthe problem of stroking. ball 122 and no longer concerns himself with the problem of positioning club 100. Golfer 10 concentrates on preventing rotation of band 120 (and thereby line 105) during his back and forward stroke.
While an average golfer may actually rotate band 120 sometime during the back stroke, for example, the golfer at least attempts just prior to striking golf ball 122, to maintain line 105 pointed generally in the direction of the visualized. target hole 136. In this manner, he insures ball 122 being hit and moving along trueline 112 directly into target hole 135.
With the provision of an individuals sighting error correction line 105, similar to sight line 12 of FIG. 1, golfer 10 can consistently and reproducibly aim club face 110 directly at hole 135. It will be noted that golfer 10 is not actually square with club face 110. However, a grip 120 on shaft 107 has a flat portion 122 parallel to band 120 so that the golfer properly grips the club to assist him in stroking along true line 112.
Referringnow to FIG. 4-, in a specific example, club 100 may have correction line 105b formed as a 3/32 inch thick line on upper face 125 and extending from front face 110 to the back edge 126 of putter 100, as
shown. In FIG. 4, line l05b provides a correction 1R (1 to the right of true line) as indicated by notation 108a on the end of handle 120. Band 120 may be L68 inch (the diameter of a standard American golf ball) wide white band on top face 125 with the band extending from front face 110 to the club back edge 126, a distance of approximately 3 inches. White band 120 contrasts with the dark color of the remaining portion of top face 125 so that the edge lines 115-116 are readily seen.
Club 100 may itself be used as a means for the golfer to calibrate his eyes and check his sighting error. The player first assumes the ball address stance. He then points line 105 at where he believes the target is by rotating the club. In this way, line 105 is effectively rotated approximately about a point defined by center 1050. The golfer holds putter 100 in place on the ground and then moves behind the club to view band 120. Band 120 and its lines 115-116 should be aimed directly at target 135 assuming that his sighting error has not changed. If the white band 120 is not pointed directly at target 135, the golfer may takeinto account the small eye variation in the angular sighting error for that day by adjusting his reading of the putt. In this manner, there is provided a self-calibration procedure for the golfer.
It has been found that while any one individuals sighting error is basically a constant value, there may be a variation about that personal sighting error plus or minus one-half degree. Accordingly, a serious player or a professional may prior to a round of golf determine his sighting error on that day and select for that day a putter from a matched set which covers his range of sighting error. v
In professional golf, it is permissible under the rules for a caddy to assist a golfer in lining up club for a putt. Accordingly, the caddy can view band 120 from behind the player and tell'him if lines 115-116 are lined up with true line 112. If not, the caddy may then suggest that the putter be turned to precisely aim at the desired direction.
The clubs themselves may be used t determine the proper sighting error correction line for an individual. A golfer is first given a club that has a zero degree sighting error correction line and is told to point that line directly at the target. The person fitting the club stands behind the player with the plane formed by the front of his body normal to true line 11 and views band 120.
If band 120 is pointed to the right then an R correction is required with the fitter estimating the proper number of degrees for the sighting error angle. A putter is provided with that error correction and the golfer lines up the new club in the manner previously described. If the fitter views band 120 as pointed directly at the target, a proper putter has been selected.
On the other hand, if band 120 is pointed to the right of the target, then a higher valued angle is required. If band 120 is pointed to the left of the target, then a lower valued angle is required. The golfer is then given a club with the new estimated value of angle and the foregoing process is continued until band 120 is pointed at the target to the satisfaction of the fitter.
Referring now to FIG. 5, there is shown a still further embodiment in which putter 100a has a correction line 1051) similar to the correction lines in FIGS. 3-4. However, in FIG. 5, the edge lines 115a-116a of band 120a are no longer normal to club face but form an angle therewith equal to the angle formed by line 1051:. In this manner, all three lines, 105b, a and 116a are parallel to each other and all provide sighting error correction. However, band 120a can no longer be used for fitting or calibrating the putter 100a in the manner previously described.
While the golf clubs 100 and 100a in FIGS. 3-5 are all shown as putters, it will be understood that other golf clubs may have the sighting error correction line as well as the band. However, for the correction line to be used on the top face, there must be a sufficient distance between the clubs front face and back edge to allow the golfer to 'view and sight along the correction line. Accordingly, woods generally provide a top face which would incorporate a sufficiently long correction line.
It will be understood that correction lines 105, 105b may be formed other than on the top face of the club. What is important is that the correction line be visible to the individual when holding the club in the address stance.
Band 120 and line 105 are preferably formed and colored on club 100 in the manufacturing process. However, stripes having correction lines of differing angles and directional deviations may be supplied as tapes with press contact adhesives. Thus, a tape would be applied to a club providing the proper error correction for an individual.
1. A method of correcting for an individuals inaccurate aim when putting and thereby improving said individuals accuracy and consistency in putting a golf bzfall with a golf putter comprising the sequential steps 1. said individual, while assuming a substantially normal putting stance, orienting a sight line so that it appears to said individual to be aimed at a target, which sight line is located upon or adjacent a point from which a golf ball normally would be putted by said individual while in said stance,
2. determining said individuals inherent and personal sighting error as the angle between an extension of said apparently accurately aimed sight line to a location laterally of said target and a true line extending between said point and said target, and
3. said individual putting a golf ball while assuming said substantially normal stance with a putter having correction stripe-like indicia on the upper surface of the putter head while attempting to maintain said correction stripe-like indicia aimed at a putting target when positioning the putter head rearwardly of the ball and when striking the ball during the putting stroke, which correction stripelike indicia is sloped relative to a real or imaginary line normal to the striking face of said putter at an angle equal to said idividuals sighting error angle.
2. The method of claim 1 in which the stripe-like indicia on the upper surface of the club head extend substantially from the putter striking face to the back edge of the club head.
3. The method of claim 1 in which the individual in his normal putting stance has both feet on the same side of said true line.
4. The method of claim 1 in which said indicia on the surface of the club head is located between the shaft and the toe of the club head.
5. The method of claim 1 in which said putter has said indicia within a band on said upper surface of said club head, said band having parallel edges extending normal to the striking face of said putter.
6. The method of claim 1 in which said determining step includes (a) detecting a first intersection of said true line with a plane and (b) detecting a second intersection of said sight line extension and said plane.
7. The method of claim 1 in which aid determining step includes (a) detecting a first intersection of said true line with a flat real plane perpendicular to said true line and (b) detecting a second intersection of said sight line extension and said flat real plane, and observing the deviation of said second intersection from said first intersection.
8. The method of claim 7 in which said determining step further includes disposing said target within said Piii inethod of claim 7 in which said determining step further includes disposing said target in front of said real plane.
10. The method of claim 7 in which said flat real plane is in the form of a chart and said detecting a second intersection step includes detecting, with respect to markings on said chart, the intersection of said sight line extension and said chart.
1]. A method of correcting for an individuals inaccurate aim when putting and thereby improving said individuals accuracy and consistency in putting a golf ball with a golf putter comprising the sequential steps performed by said individual of:
l. orienting, while assuming a substantially normal putting stance, a sight line extension so that it appears to said individual to be aimed at a target, which sight line is located upon or adjacent a point from which a golf ball normally would be putted by said individual while in said stance,
. observing his or her inherent and personal sighting error as the lateral distance between an extension of said apparently accurately aimed sight line and said target, and
3. putting a golf ball while assuming said substantially normal stance, with a putter having correction stripe-like indicia on the upper surface of the putter head while attempting to maintain said correction stripe-like indicia aimed at a putting target when positioning the putter head rearwardly of the ball and when stroking the ball during the putting stroke, which correction stripe-like indicia is sloped relative to a real or imaginary line normal to the striking face of said putter sufficient to compensate for said individuals sighting error.
12. A method of fitting an individual with a golf putter to correct the individuals inaccurate aim when putting thereby to improve the individuals accuracy and consistency in putting comprising the steps of l. requiring the individual to assume his or her normal putting stance,
2. requiring the individual to orient a sight line so that it appears to the individual to be aimed at a predetermined distant target, which sight line is located upon or adjacent a point from which a golf ball would normally be putted while the individual is in said stance,
3. detecting said individuals sighting error, after the individual has apparent accurately aimed the sight line, as the angle between an extension of said sight line to a location laterally of said target and a true line extending between said point and said target, and
. providing said individual with a putter having correction stripe-like indicia on the upper surface of the putter had which is sloped relative to a real or imaginary line normal to the striking face of said putter at an angle equal to said individuals sighting error angle.
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U.S. Classification 473/409, 33/263, 473/242
Cooperative Classification A63B69/3676, A63B69/3614