| 摘要 |
<p>PROBLEM TO BE SOLVED: To make it possible to allow the ball hit by a prescribed swing to arrive at a desired position by making the moment of inertia around the shaft axes of the heads of all clubs constant and making the torsional vibration frequencies around the shaft axes of the clubs larger as the shaft number is smaller. SOLUTION: The moment of inertia J around the axes of the heads is constant and the torsional vibration frequencies around the shaft axes of the clubs are made larger as the shaft number is smaller. The torsional angleθof the shafts with respect to the grip during the down-swing is corrected in the degree of opening of the heads as the irons are longer. Then, the occurrence of the sliced ball of the long irons which is liable to arise with an average golfer is lessened. If the moment of inertia around the shafts is constant, the respective clubs are formed to the state of harmonizing the return of the clubs over the entire part of the set and, therefore, the ball hit by the prescribed swing flies by drawing the preset trajectory of the ball flight, by which the ball is made to arrive at the desired position.</p> |
