2. Description of the Prior Art For years, golfers have relentlessly tried to improve their game by searching for the ideal set of clubs wherein each club"feels"the same and performs in a consistent manner. As such, numerous methods have been formulated in the attempts of dynamically matching the set of golf clubs.

While many systems have been developed that match one club in a set to the other clubs in the same set, no one has developed a method of precisely determine the specific requirements of the individual golfer and producing a properly matched set of clubs that meet these requirements, which is the basic purpose of the present invention One such method for matching golf clubs in a set is to provide the set with the same moment of inertia with respect to a common swinging axis. Such a method is disclosed in U. S.

Pat. No. 3,698,239 issued to Everett, III. These methods use the assumption that having identical moments per club will inherently provide the golfer with better feel and more control. Though the determination of the moment of inertia is important in dynamically matching clubs, it is not the only element needed for optimum control for the golfer. In fact, these methods fail to discuss the flexural rigidity, which is the stiffness of the shaft of the golf club. For a golfer to adequately "feel"that the clubs are matched, this flexural rigidity must be the same throughout a set of irons and woods. Unfortunately, with the methods discussed above, as the shaft shortens, the flexural rigidity increases. Hence, providing for a set of clubs, which are not matched to the user correct; but are instead, matched to each other.

Other methods have been provided for improving the golfer's game by adjusting the shaft of the golf club, wherein the shafts of each set of clubs is provided with the same frequency. Such as the method disclosed in U. S. Pat. No. issued to Kilshaw and U. S. Pat. No. 4,070,022 issued to Braly. In both of these patents, the shafts of the clubs are provided with identical frequencies. The measurements are accomplished without the heads of the clubs being attached thereto. Once the heads are attached, weight is added to the shaft. This will inherently provide for the frequency to alter per club, thereby providing for clubs having different frequencies.

Hence, it is seen that none of these previous efforts provide the benefits intended with the present invention, such as providing a set of golf clubs which feel matched by the user.

Additionally, prior techniques do not suggest the present inventive combination of component elements as disclosed and claimed herein. The present invention achieves its intended purposes, objectives and advantages over the prior art device through a new, useful and unobivous combination of component elements, which is simple to use, with the utilization of a minimum number of functioning parts, at a reasonable cost to manufacture, assemble, test and by employing only readily available material.

SUMMARY OF THE INVENTION The present invention provides a matched set of golf clubs, wherein each club in a set of golf clubs, irons, woods, or a combination thereof, provides the golfer with precisely the same feel, related to the golfer's swing when the club is swung, and to the contact between the head of the club and golf ball when the ball is hit.

In order to accomplish this correct feel and to provide for the clubs to be matched dynamically, three criteria of teach club must be equated; specifically, (1) a constant flexural rigidity of each complete iron and each complete wood, (2) the selected moment of inertia, and (3) the precise location of the center of gravity's for each club in the set.

The single most important element of a golf club is the stiffness of the shaft which is used for constructing the club. This stiffness, also known as the flexural rigidity, must be constant throughout a particular set for providing consistency in performance from the clubs. For determming the optimum flexural rigidity for any shaft, the user or golfer of the club uses a flexural rigidity test means. This test means allows the user to determine the appropriate stiffness of the club for their particular swing. This correct stiffness provides the best feel and most consistent results. The proper feel obtained by the golfer in combination with the structure of the club will work simultaneously for improving one's game in golf.

In order to obtain maximum distance from any golf club, a golfer must be fitted with the maximum head weight with which they can generate the maximum club head speed. For determining this maximum head weight, the moment of inertia about the golfer's wrist is mathematically calculated. Once calculated, the clubs are adjusted accordingly by providing the proper head weight per club.

The final step in customizing the set of clubs is to establish a more ideal center of gravity for each club. Such an adjustment of the center of gravity will render a club which will perform in a constant manner and will additionally provide constant feel between each club.

Accordingly, it is the object of the present invention to provide for a matched set of clubs and method of producing the same which will overcome the deficiencies, shortcoming, and drawbacks of prior dynamically matched golf club sets and methods thereof.

It is another object of the present invention to provide for a matched set of clubs, wherein each club in the set provides the golfer with precisely the same feel.

Yet another object of the present invention is to replace the shafts of an existing set of golf clubs so as to allow each club of the set to have the same feel.

Still another object of the present invention, to be specifically enumerated herein, is to provide a matched set of clubs in accordance with the preceding objects and which will conform to conventional forms of manufacture, be of simple construction and easy to use so as to provide clubs that would be economically feasible, long lasting properly customized and relatively trouble free in operation.

The foregoing has outlined some of the more pertinent objects of the invention. These objects should be construed to be merely illustrative of some of the more prominent features and application of the intended invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner of modifying the invention within the scope of the disclosure. Accordingly, a fuller understanding of the invention may be had by referring to the detailed description of the preferred embodiments in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic side view of a golf club illustrating the parameters used in calculating the moment of inertia.

FIG. 2 is a side view of the components of a golf club prior to assembly.

FIG. 3 is a diagrammatic side view of a golf club illustrating the parameters used in calculating the center of gravity.

FIG. 4 is a side view of a golf club in a balance state a nd illustrating the center of gravity.

Similar reference numerals refer to similar parts through-out the several views of the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention provides a set of golf clubs, such as irons, woods, or a combination thereof, which are synchronized for matching the particular swing of a particular golfer. This will provide for a set of customized clubs which will inherently improve the game of the user.

As seen in the drawings, a golf club 10 is provided with a head 12 having a head weight M, a shaft 14 having weight M. The shaft 14 future includes a tip or first end 20 and a butt end 16. A grip 18 is attached to the butt end 16 and a hosel 24 of the head 12 is attached to the first end 20 of the shaft 14. the weight of the club plus any additional weight added to the end of the shaft has a weight has a weight M.

The golf club 10 further includes a total length L which encompasses the head and shaft. The shaft 14 includes a shaft length L which encompasses the tip or first end 20 and the butt end 16.

For optimizing the performance of the golfer, three characteristics of the conventional golf club are taken into consideration. These three characteristics include: (1) A constant flexural rigidity of each complete iron within a set of irons and each complete wood within a set of woods, (2) a constant moment of inertia for each iron and each wood, and (3) the center of gravity as it relates to the swing of the individual golfer. Thereby, providing for a set of flexural momentized golf clubs. The determination of each characteristic is discussed as follows: Flexural Rigidity Flexural rigidity relates to the stiffness of the shaft of a particular golf club. To maintain a constant frequency, the flexural rigidity of the completed club must remain constant.

The process for providing a set of golf clubs with the same flexural rigidity is of the utmost importance. In order to accomplish this, the shaft, including the head, provides for the particular club to have the same frequency. The shaft, without the head, may not have the equivalent frequency of the other clubs in the set. It is the combination of the head and shaft which makes up the equivalent frequencies, thereby providing one of the aspects for making each club in a set to have the same feel.

For providing this equivalent frequency per club, the shaft, in combination with the head, is placed on a conventional frequency analyzer at the desired length L. The frequency is measured. If the measurement is not the desired frequency, the head is removed and the tip or first end 20 of the shaft 14 is cut. This cutting of the tip or first end 20 will alter the frequency, making it stiffer. The head 12 is then placed on the shaft 14, the desired length L is reestablished, and the club is reattached onto the frequency analyzer. The test is performed again and the process of removing the head 12, cutting the tip or first end 20, measuring the length L, reattaching the head 12 to the tip or first end 20, and reattaching the club 10 to the analyzer is repeated until the desired frequency is obtained. All cutting is done at the tip of first end 20 of the conventional shaft. All frequency measurements are accomplished with the head 12 attached to the shaft 14. No cutting is performed on the butt end 16 of the shaft until after the required frequency is obtained, the shaft is then but cut to provide the desired playing length L for the club. this playing length L must be established before the frequency is measured and must be reset each time the tip or first end 20 is cut.

The process described above is continued with each club per set. The frequency of each club, with the head attached thereto, in a set of irons is within the range of 260 to 345 cycles per minute, while the frequency of each club, with the head attached hereto, in a set of woods is within the range of 230 to 300 cycles per minutes. It is noted that within each set of clubs, the frequency may be off by approximately plus or minus 1 cycle per minute, due to the added weight of the conventional attaching means for securing the head to the tip or first end of the shaft. It is noted that the only way to effect the frequency of a particular club is by tip cutting.

For detenmning the appropriate frequency or flexural rigidity for a particular golfer, a set of preset test clubs is used. Each test club is built to a predetermined frequency such that the set of test clubs covers the full range of available frequencies. The difference in frequency from one test club to another should not exceed 5 cycles per minute.

Moment of Inertia For determining the moment of inertia, the user hits with preset test clubs. These preset clubs have predetermined set shaft stiffness and frequency. Ideally, the golfer should be fitted with the heaviest head that will provide the highest sped. Testing has shown that the ideal moment of inertia is directly related to the club head speed accomplished by the golfer during testing.

Center of Gravity