JPH01166781A - Golf club set - Google Patents

Abstract

PURPOSE: To make it possible to fly a hit ball in a predetermined direction on a constant swing even if using any number of club, by making equal of an inertial moment value of a head on a rotary axis. CONSTITUTION: Inertial moment Is of a head around a shaft axis of each golf club is made constant. As a means to fall into the same Is of each number of the club, as it is possible to adopt a method of combination of head weight (m), radius of rotation (r) and distance between shaft axis and gravity center (d), but the head weight (m) of the club has an almost determined value to all a primary moment called 'swing balance' into the nearly same value. Therefore, by using the heat widely using at present, the weight of the head is used without any modification, and (r) and (d) are changed and combined to fall into the same Is value. When hitting a ball by using this set of the clubs, the Is of the head at an impact time becomes the same for all of the clubs in the set, and the head condition at the time is kept constant, so a locus of the hitting ball can be made constant for each number of the club.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a golf club set consisting of a plurality of golf clubs.

(Prior art) A golf club set is a set of any number of wood clubs or iron clubs that are correlated under certain conditions. ) to number 5 (clique), nine iron clubs from number 1 (driving iron) to number 9 (brick), and special clubs called butter, pitching wedge, sand wedge, etc. A golf club set (hereinafter referred to as a set) is a golf club set (hereinafter referred to as a set) made by selecting and combining wood clubs and iron clubs.When only wood clubs are used, it is called a wood set, when only iron clubs are used, it is called an iron set, and the combination of both is called a wood set. is called a full set.

The rules of golf allow up to 14 clubs to be carried and used when playing, and the universal combinations are wood clubs with numbers 1, 2, 3, and 4, and iron clubs with numbers 3, 4, and 5. , 6, 7, 8° A set of 14 clubs is generally made up of 7 clubs number 9, and 3 clubs: back, sand wedge, and pitching wedge.

The set clubs are designed so that when the golfer hits the ball with a certain swing, the ball will fly a predetermined distance along a preset trajectory for each club. is necessary.

However, no matter how constant the golfer's swing, satisfactory results will not be obtained unless the clubs of each club are designed to accommodate this.

For this reason, club sets are made by adjusting the shaft length, head weight, lie, loft, etc. of each club in a correlated manner, but in reality, this set is made by adjusting the shaft length, head weight, lie, loft, etc.・It is difficult to stably hit a ball that follows a preset trajectory even when using a custom club.

One of the reasons for this is that in a golf brake, the deflection of the head near the impact of hitting the ball against the pole is extremely important, and it has been found that the degree of deflection of the head greatly influences the direction of the ball.

An important element that determines the degree of deflection of the head is the moment of inertia of the head around the shaft axis (hereinafter referred to as Is), which is shown as Is in FIG.

For example, if we take an iron set as an example, many golfers use long irons (numbers 1 to 3) to easily result in slicing balls, while short irons (numbers 7 to 9) tend to result in hooked balls. Is for each club as one
It is possible that there is a difference.

In other words, in a golf swing, the head begins to return in the middle of the downswing, but after that the head naturally returns due to inertia.In this case, the moment of inertia of the head around the shaft axis acts, so the moment of inertia is reduced. Large and small are important as they affect the return of the head of the swing.

In other words, in the case of a long iron, since Is is small, the inertial force returned by the head is weak, and the head opens upon impact, resulting in a sliced ball. In the case of a short iron, since Is is large, the inertial force of the head is strong, and the head closes at impact, resulting in a hooked ball.

In conventional sets, this Is has a different value for each number, and no set has been seen in which this Is is intentionally aligned to form a stepped shape.

As an example, the results of measuring a conventional set based on FIG. 2 are shown in Table 1. ([Table-11 (*Is is expressed as Is=IG+md"=m-r2+md".

G = Moment of inertia around an axis parallel to the shaft axis and passing through the center of gravity of the head.

Further, IG is expressed as IG=m−r2.

m: Head weight r: Rotating radius j: Distance between shaft axis and center of gravity) The number 1 Is of the wood club at the center of gravity [Table-1] is 334
8 (9 cm”), and the Is of No. 5 is 3143 (
9 cm2), and the number 3 of the iron club is 5061.
(9・cm2) and number 9 is 6307 (9・cm2)
And the difference is huge.

When making the same swing using this club set, there is a problem in that sliced balls tend to occur and it is difficult to obtain a predetermined ball trajectory.

(Means for Solving the Problems) In order to solve the problems, the present invention provides the ability to hit the ball in a preset direction under a certain swing, regardless of the number of clubs in the set. 15t is made constant for each club so that Examples thereof are as follows.

(Example) As a means of aligning l57j of clubs for each number, m,
Although it is possible to do this by various combinations of r and d, the club head weight of 1 m has a practically fixed value in order to equalize the first moment called swing balance for each club, and as an example of the present invention, Using a currently widely used head, the weight of the head is basically used, and r and d are changed and combined to achieve this Is.
The values are the same.

An example of a full set combining the head weight i1m, the rotation radius r, and the distance d between the shaft axis and the center of gravity is shown in Table 2.
It is as follows.

[Table 21 shows the measured values of a wood club and an iron club in a full set with the same Is value (metal wood is used as the wood) cTable 2] The set means are a wood club and an iron club. The set is not limited to a full set consisting of, but may be a set of only wood clubs or a set of only iron clubs.

[Table 3] shows the measured values when the Is values in the iron sets are the same.

[Table 31 Here, IIl of IG is made the same for each count, but it may be different for each count.

(Effects of the Invention) Since the present invention has the above configuration, when a ball is hit using this set, after a certain swing, a club with a number corresponding to the required trajectory of the ball is selected from the set. When you swing the ball, the Is of the head at the time of impact is the same for all clubs in the set, so the return of the head at impact remains constant, so the trajectory of the ball is determined by the club of each number. This is a golf club set that has a uniform effect.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the moment of inertia of the shaft axis of the golf club and the head, and FIG. 2 is an explanatory diagram showing the measurement positions of the golf club head and the shaft axis for aligning Is. IG=m−r2 is the moment of inertia about an axis parallel to the shaft axis and passing through the center of gravity of the head. m: Head weight r: Rotation radius d: Distance between shaft axis and center of gravity G: Center of gravity

Claims (1)

[Claims] A golf club set comprising a plurality of golf clubs, each of which has a head having the same moment of inertia value with the shaft axis of each golf club being the rotation axis.