Abstract: Disclosed is a golf club group comprising a plurality of golf clubs having the same number, in which each golf club shaft of the golf club is composed of a plurality of bias layers and a plurality of straight layers which are wind-formed so that it may be shaped into a tapered circular pipe having a diameter which gradually larger towards to is a butt end. The plurality of golf club shafts have approximately the same flexibility, assuming that each golf club shaft is constructed so that each straight layer may have the same thickness over the total length of the shaft, a distribution curve of flexural rigidity the shaft is set as a reference curve.

Abstract: A method for selecting a golf ball whose performance characteristics match a golfer's critical playing characteristics for the purpose of reducing the golfer's score. The method comprises the steps of determining a golfer's critical playing characteristics, prioritizing ball performance characteristics, and selecting a golf ball from a predetermined set of golf balls which best matches the golfer's critical playing characteristics to ball performance characteristics.

Abstract: A high speed camera takes an image in the vicinity of a ball 3 and a club head 12, while a high speed camera 5 takes an image in the vicinity of the top of the swing of a golfer 1, and the images are recorded in a high speed video tape recorder 6. The recorded images are reproduced, swing time, a swing speed and a head speed are detected using a personal computer 15, and a shaft with an optimum flex for the golfer is selected based on the swing time, the swing speed, the swing time and the head speed, or the swing speed and the head speed.

Abstract: A high speed camera takes an image in the vicinity of a ball 3 and a club head 12, while a high speed camera 5 takes an image in the vicinity of the top of the swing of a golfer 1, and the images are recorded in a high speed video tape recorder 6. The recorded images are reproduced, swing time, a swing speed and a head speed are detected using a personal computer 15, and a shaft with an optimum flex for the golfer is selected based on the swing time, the swing speed, the swing time and the head speed, or the swing speed and the head speed.

Abstract: A high speed camera takes an image in the vicinity of a ball 3 and a club head 12, while a high speed camera 5 takes an image in the vicinity of the top of the swing of a golfer 1, and the images are recorded in a high speed video tape recorder 6. The recorded images are reproduced, swing time, a swing speed and a head speed are detected using a personal computer 15, and a shaft with an optimum flex for the golfer is selected based on the swing time, the swing speed, the swing time and the head speed, or the swing speed and the head speed.

Abstract: A golf club spine finder comprising a shaft holding member which comprises a bottom wall and a vertical member. The vertical member comprises a plurality of extended members, each extended member further comprising extended member apertures. A gripping member functions to secure the shaft holding member in a substantially upright position. A golf club shaft is then removably inserted through the extended member apertures of the shaft holding member, the golf club shaft comprising a traditional grip end and club head end. An indicator handle comprises at least one aperture further comprising roller bearings therein and a display. The golf club shaft is removably inserted through the indicator handle substantially near the club head end of the golf club shaft. The indicator handle functions to measure the flexure of the golf club shaft at differing angles when depressed downwardly as the golf club shaft is rotated.

Abstract: A tubular metal blank for the production of golf club shafts for iron clubs, the blank being at least 44" in length, having a cylindrical tip portion, a cylindrical butt portion, and an intermediate, integral, tapering portion, remaining parameters of the blank including the material, the taper angle, the length of the intermediate portion, and the wall thickness being so chosen as to produce a blank of a stiffness characteristic such that by appropriate trimming of the butt and tip portions of the blank, the blank can be used to produce a shaft for any golf club from a 1 iron to a sand wedge in any of the recognized flex ranges Tour Stiff, S, R and A. There is also disclosed a method of producing a golf club shaft and a means of determining how much to cut from the blank to produce a shaft.

Abstract: A method for manufacturing a plurality of club shafts for an individually matched set of golf clubs is provided herein. The method includes using a specifically designed and separate mandrel for each club shaft of the matched set. Further, the method includes sequentially wrapping a specifically designed and separate group of patterns around each mandrel for each club shaft of the matched set. This procedure allows the manufacturer to specifically design each club shaft of the set of golf clubs. The resulting individually matched set of golf clubs has more consistent feel, flexure, frequency, weighting and torque characteristics. Additionally, the club shafts provided herein have improved swing weight characteristics for lighter heads.

Abstract: 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 the present invention the clubs are matched dynamically. The clubs will have one or all of the following characteristics: (1) a constant flexural rigidity of each complete iron and/or each complete wood, (2) a constant moment of inertia, and (3) a the center of gravity which is calculated by using a constant force for the shortest club in the set.

Abstract: A device-coupled golf club 80 includes a club head 64 which is assembled with a shaft 22 by use of a coupling device 40. Club head 64 is formed with a hosel 68 which is formed with a bore 70 having threads 76 formed in an upper portion thereof and a floor 74 at the base thereof. Coupling device 40 is formed with a body 41 having a bore 42 formed axially therethrough. A flange 44 is formed radially outwardly from one end of the body 41 and is formed with threads 50 from the flange toward the opposite axial end of the body. A ferrule 56 is located on shaft 22 and a tip end 30 of the shaft is inserted into bore 42 of body 41 and secured there by an epoxy glue 82. An exterior surface of body 41 is formed with threads 50 which engage threads 76 formed within bore 70 of hosel 68 to removably secure device 40 with head 64 whereby shaft 22 is assembled with the head 64 to form club 80.

Abstract: A tubular blank for producing golf club shafts comprises a butt section having a uniform cross-sectional configuration along its length, a tip section also having a uniform cross-sectional configuration along its length, and a tapered section interconnecting the butt and tip sections. Metallurgically formed rifling on the interior surface of the blank extends throughout the entirety of the butt, tip and tapered sections. The golf club shafts produced from these blanks have increased strength and stiffness which is a direct result of the interior rifling. A set of golf club shafts preferably is produced from a group of these tubular blanks with each blank of the group having the same length and the same natural frequency. Predetermined portions are then selectively removed from the tip and butt sections.

Abstract: A golf club shaft including a tip section, a grip section, and a main body section extending from the proximal end of the tip section to the distal end of the grip section. The slope of a first portion of the outer surface of the main body wall is different than the slope of a second portion.

Abstract: A high speed camera takes an image in the vicinity of a ball 3 and a club head 12, while a high speed camera 5 takes an image in the vicinity of the top of the swing of a golfer 1, and the images are recorded in a high speed video tape recorder 6. The recorded images are reproduced, swing time, a swing speed and a head speed are detected using a personal computer 15, and a shaft with an optimum flex for the golfer is selected based on the swing time, the swing speed, the swing time and the head speed, or the swing speed and the head speed.

Abstract: Vibrational analysis is used to map the true sweet spot of a golf club. The testing device, method of testing, method of designing a golf club, and tuned golf clubs are disclosed.

Abstract: Methods of making a set of golf clubs and shafts that are matched according to vibration frequency are disclosed. The methods may include a random selection of shafts from a stock of raw shafts, wherein the vibration frequency of each shaft is determined and then each shaft is assigned a club head number. By determining conversion values based on desired and actual club head weights for each shaft and by determining a value between a desired and measured frequency of each shaft, a total frequency conversion value may be obtained. The total frequency conversion value may then be used to determine an amount to trim each shaft and thereby linearly match each shaft in the set based on vibration frequency and an increase in club head number.

Abstract: The club length and club frequency attributes of each of a plurality of golf clubs in inventory are obtained and the data are arranged in a two dimensional array. The golfer's swing frequency for a test club of a particular test club length is measured. An inventory club is selected, from the inventory array having substantially the same length as the test club and having the closest frequency to the golfer's swing frequency of any inventory club in that array of that length.This process can be employed for one or more clubs. Alternatively, only a few club lengths can be tested to obtain swing frequencies for those clubs. The swing frequencies of any intermediate, untested club lengths are interpolated by standard numerical analysis or obtained by plotting the data points and connecting them with a curve.

Abstract: A set of golf clubs including a golf club comprising a head and a shaft, wherein the head has an extension and the shaft is joined to the extension and extends therefrom at a shaft tip, the shaft tip having a diameter of 0.370-0.4 inch and the head is approximately 220 cc or greater.