US 3516674 A
Description (OCR text may contain errors)
June 1970 Q J. A. SCARBOROUGH 3,516,674
GOLF PUTTER Filed Dec. 28, 1967 Baby scar/aw aF LIGHTER.
DEA/511v 1mm STE/KIMB- BLADE Ws/aH-r HERA/.5 ARE OFIEQUIIL MASS INVENTOR. JAMES ANTHONY SCARBOROUGH.
United States Patent US. Cl. 273-169 3 Claims ABSTRACT OF THE DISCLOSURE A golf putter having a relatively thin striking blade rnade from a relatively dense material. A =hosel is affixed to the blade centrally thereof. Positioned against the rear of the blade in interlocking relationship therewith is a body section made of lighter density material than the blade. First and second weight means of equal mass are secured by threaded screws to the rear of the body section and equally spaced from the center line of the club head to minimize twisting of the club. Each screw extends through one weight means and the body section into threaded engagement with a boss at the rear of the striking blade.
This invention relates to a golf club and more specifically to a putter head of an improved design.
It is an object to provide a putter of novel construction and improved accuracy.
A broad object of my invention is to provide a putter which, by virtue of its torque, tends to align its face plate perpendicular to the direction of the stroke before the ball is struck.
Another object of my invention is to provide a golf putter which is optimally designed according to the laws of physics.
Another object of my invention is to provide a putter having a weight distribution which minimizes twisting of the shaft when an oif-center putt is made.
Another object of my invention is to provide a putter which transmits maximum feel when the ball is struck.
Another object of my invention is to provide a putter which tends to maintain proper alignment when the ball is struck with an off-center stroke.
A specific object of my invention is the provision of a formula for optimizing the design of a golf putter head.
Golf is a game which is attracting more and more enthusiasts each year. As these many golfers are aware, probably one of the most critical and diflicult aspects of the game is putting. Here accurracy, skill, and stroking force are required to enable the golfer to minmize his score. Many types of putters have been suggested to help puttings skills. Putters having various weight distributions, face designs, and various sighting arrangements are available. However, no one has heretofore carefully examined the dynamics of the putter and putting strokes and then designed a putter according to the laws of physics.
Accordingly, it is a principal object of this invention to provide a putter optimally designed which has a selfaligning weight distribution.
In accordance with the foregoing, as 'well as in accordance with other object and advantages of my invention, reference is made to the following specification, claims, and drawings in which:
FIG. 1 represents a force diagram detailing the basic principles of my design.
FIG. 2 is a perspective view of the preferred embodi ment of my invention.
FIG. 3 is a side elevational view of the putter of FIG. 2.
FIG. 4 is a front elevational view of the putter embodying the present invention.
FIG. 1 represents the putter of FIG. 2 and its various forms in diagrammatic detail. In these figures, M is the 3,516,674 Patented June 23, 1970 ice mass of the striking plate and any adjacent filled block and is considered as being concentrated at the center of mass of these elements. The quantities m and m represent the masses 20 of FIG. 2 viewed as concentrated at the centers of mass of these weights, and located behind the extremities of the striking face at distance and respectively. The shaft is attached to the putter head at the point of intersection of the force F and the striking face. The distance S is measured from the point of intersection of force vector -F along the striking face to the intersection of line L and the striking face. Distances r and r are measured along the striking face from l to the point of intersection of vector F and from 1 to the point of intersection of vector F along the face, respectively.
In this diagram, the putter shaft is exerting a force F on the putter head, with F being in the intended direction of travel of the ball. As often happens in the putting stroke, the face plate is not perpendicular to F, but is at the angle 0 as shown. With the putter traveling in the direction of F but at the angle of orientation 0, the golf ball rebounds from the surface at angle 26 from the desired direction. The error is thus doubled, and many missed putts occur.
Further, if the putter strikes the ball so that the point of impact is not directly in line with the center of mass of the whole club head, then the impact gives a torque to the club head, twisting it off-line, with the resultant error in the direction of the ball being again doubled.
Finally, when the ball is stroked, the impact should transmit as much impulse as possible through the shaft to the hands of the golfer, thus giving the maximum of what the golfer calls feel. This implies that, for a given force of impact, the club head should receive minimum energy, With most of it being transmitted up the shaft.
Referring to FIG. 1, the force F of the shaft on the putter head during the stroke causes an acceleration of the club head. During this acceleration, the effective forces acting are P, 1, f and f as shown in the figure.
The torque T about the axis of the shaft on the club prior to impact is given by Noting that f=Ma, f =m a,f =m a we see that the torque is proportional to the quantity This quantity should be zero when 0:0 as We do not wish any torque present tending to disalign the putter. Resolving the equation, this implies that m r -m I' MS=0 This then is the equation for perfect balance of the club head.
In order to obtain the maximum tendency of the putter to maintain its 0:0 alignment, the correcting torque (m l -l m l -i-ML) sin 9 must be as large as practical. Therefore, the quantity m l +m l +ML should be as large as practical.
The masses are restricted, however, as a puter weighing much over 30 grams feels heavy and cumbersome to most golfers. Also, if l and I are more than a few centimeters, or are unequal, the resulting configuration then has an appearance which most golfers would find displeasing or awkward. Since the putting phase of golf is strongly dependent upon psychological factors, it is suggested that the choices S=0, L =L and r =r be made for the sake of appearance. Note, however, that this is a subjective'choice and not a design limitation.
If the above choice is made, then we have m =m necessarily.
The putter head should have as much rotational inertia as practical so that it will not be twisted off-line upon striking the ball. The quantity which represents the approximate rotational inertia for center shafted putter if a light weight filler block is Used, should be as large as practical. This implies that m r +m r be as large as practical. With the symmetric choice r =r already having m =m l =l and S=0, this simply means that the putter should be as wide as convenient and the lengths l 1 as long as convenient. A width r |r E5 centimeters seems close to the maximum. A width much more than this appears unpleasant to most people.
The conclusions reached are:
(a) The masses m and m are equal and are located at equal distances l and I behind the club face;
(b) R =R z25 centimeters;
(c) m +m +M=30O grams.
The resulting design has the following features:
(a) The mass M of the insert or filler block is quite small, and is centered directly behind the desired point of impact. Clearly, the filler block may be left out altogether.
(b) The shaft is mounted at or very near the center of the blade. Actually, if the shaft is inclined at a small angle, as would be necessary for a conventional putting stance, the distance S may still be zero, although the ball is best struck at what is apparently a non-zero distance from the shaft. This preferred impact point is pointed to by the alignment line (see Diagram 1) which also aids in aligning the putter. The above theoretical treatment remains valid to a good approximation if the shaft is mounted slightly off-center.
(c) The putter head twists minimally upon receiving an olf-center hit.
(d) The correcting torque actually tends to align the putter (i.e., cause 0 to be equal to zero) during the stroke.
(e) If the ball is struck at the designated spot on the putter face, virtually no energy goes into twisting the club face. Instead, it is transmitted up the shaft to the hands, giving maximum feel. An improperly located impact still gives essentially the same effect.
In accordance with the foregoing principles, FIG. 2 represents one embodiment of the present design, a putter of optimum design. The putter generally designated as is preferably formed of a suitable metal and is shown as a casting having substantially smooth striking face 11. The face 11 is relatively thin and has a generally elongated oval shape. The rear side is provided with rib 12 having round horizontal bosses 13 which are internally threaded. A hosel 14 approximately equally distant from both ends of face 11 provides a means of mounting a shaft of any desired construction.
The filler block 15 has a cross section generally conforming to the elongated oval shape of the putting face 11. The front surface of the block 15 is grooved to accommodate the rear of face 11. The rear edge of filler 15 is preferably rounded and is recessed at its corners. Holes 16 extend transversely through the block 15 in alignment with threaded fillets 13. Weights 20 are shaped to fit into the recesses in block 15. Threaded screws 21 extend through block 15 into holes 13.
The filler block 15 may be of any suitable material of relatively light mass, such as wood or plastic, and, as discussed above, serves primarily to give the putter a pleasing shape. The weights 20 are of a material of much greater mass than block 15 and may be, for example, lead. Preferably, the overall putter is within the design parameters of weight and size set forth above. A line 17 is etched into the upper surface of filler block 15 and provides a sighting line for visually lining up the putt.
It can easily be seen that this design minimizes twisting, and the face maintains its alignment.
FIG. 3 shows the putter of FIG. 2 in which the face plate 11 is slightly inclined to the ground when the putter is in its normal position. This is a desirable feature which tends to give the ball a slight loft and spin to allow the ball to more easily hit the putting surface for better control without skidding or bouncing. A ball hit downward into the putting surface tends to bounce. The inclination of the face is very slight and is near zero degrees. Also, the curvature of the trailing edge of the putter is clearly seen, as well as the slight curvature of the underside of the putter. This latter curvature allows an easier stroke and minimizes the drag due to inadvertent striking and scufling of the ground with the putter by the golfer when the stroke is being made.
FIG. 4 illustrates another feature of my putter. Here the shaft 25 is not perpendicular to the horizontal axis of the face plate 11, but forms an acute angle thereto. This is desired by many golfers and is more comfortable. Also, this configuration and method of shaft attachment is in conformance with United States Golf Association regulations.
The golf putter I have described is unique and is scientifically designed. In order to demonstrate practically the quality of my putter, I tested its accuracy by putting on a relatively flat grass green. From data in Golf Digest, June 1967, regarding the putting of professional golfers at the Olympic Club in the 1966 U.S. Open, the accuracy of a putter of my design is apparent.
Percent of putts made Distance in feet Professionals My putter The important feature of my design is the weight distribution with the mass being concentrated at either end of a relatively thin putting face. The particular shape, size, and use of the filler block is one of personal choice as golfers are reluctant to use equipment that is unusual. More important, the U.S.G.A. rules forbid the use of a club which deviates too much from standard. Since the approval of a design is discretionary with the U.S.G.A. rules committee, a conventional-appearing club would be more acceptable.
While the present invention has been described in detail and with reference to a preferred embodiment, obvious changes in structure, arrangement, proportions, and materials can be made without departing from the basic teachings hereof. To the extent that such modifications and changes do not depart from the spirit and scope of the invention; they are intended to be included in the scope thereof, which is not limited to the embodiment specifically illustrated.
Having fully described the invention in such manner as to enable those skilled in the art to understand and practice same, I claim:
1. A golf club head comprising:
(a) a blade of relatively heavy density material having a striking face with a centered impact area, the thickness of said blade being relatively thin;
(b) a hosel aflixed to said blade adapted to receive a shaft, said hosel being positioned substantially equidistant from the ends of said blade and immediately behind the striking face;
(c) a body section of lighter density material than said blade positioned against the rear of said blade, said section being configured to provide mating engagement with the rear of said blade; and
(d) first and second weight means of equal weight having first and second centers of mass respectively, said weight means being of density greater than said section and being positioned against the rear of said section; whereby (e) the transverse distance from the longitudinal axis of said hosel to the extension of the centers of said first and second weight means measured along said face is approximately equal and whereby the horizontal distances from the striking face to the centers of mass of said first and second weight means are approximately equal whereby the striking force is transmitted to the impact area and twisting of the club is minimized.
2. A golf club head comprising:
(a) a blade of relatively heavy density material having a striking face having a centered impact area, the thickness of said striking face being relatively thin;
(in) a hosel aflixed to said blade adapted to receive a shaft, said hosel being positioned substantially equidistant from the ends of said blade and immediately behind the striking face;
(c) boss means projecting from the rear of said blade adjacent each end of said blade;
(d) a body section of lighter density material than said blade positioned against the rear of said blade, said section being configured to provide interlocking engagement with each of said boss means and the rear of said blade, said section further being of a cross section to conform with the cross section of the blade and having the center of its mass centered behind said impact area;
(e) the transverse distances from the longitudinal axis tioned against the rear of said section and being held in place by first fastening means extending through said section into the boss means adjacent one end; and
said section is upwardly curved to a smoothly intersecting lower blade edge.
References Cited UNITED STATES PATENTS 1,133,129 3/1915 Govan 273-171 1,459,810 6/1923 Wills 273-169 1,517,476 12/1924 Tyler. 2,155,830 4/1939 Howard 273-79 2,447,967 8/1948 Stone 273 77 3,387,845 6/1968 Raub 273-77 FOREIGN PATENTS 17,929 1892 Great Britain.
GEORGE I. MARLO, Primary Examiner R. J. APLEY, Assistant Examiner US. Cl. X.R.