JPS628190B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in golf clubs.

In golf, in order to increase the flight distance of the ball, it is necessary to increase the head speed at the time of impact. Figure 1 is a diagram explaining the swing plane of the club, and in this diagram,
The swing axis is O, and the wrist movement and head movement from the opening of the swing to impact are respectively
Assuming a ₀ , a ₁ , a ₂ , a ₃ and P ₀ , P ₁ , P ₂ , P ₃ , the moment of inertia I ₁ around the swing axis O is
The distance ₀ from the swing axis O to the head _P0 becomes smaller as the swing draws a shorter arc.
As a result, the angular velocity ω around the swing axis O increases, making it possible to increase the head speed.

However _, in order to swing the club so that ₀ draws a short arc, the angle α formed by arm ₀ and shaft ₀ must be maintained as much as possible at the beginning of the swing. To achieve this, increasing the moment of inertia I ₂ around the wrist will make it difficult for the wrist to rotate.
It becomes easier to maintain α.

A conventional method of increasing this moment of inertia _I2 around the wrist is to add a heavy body such as lead to the head, but in this case, the heavy body is located far from the swing axis O. Therefore, the moment of inertia _I1 around the swing axis O also increases, and as a result, the angular velocity ω around the swing axis O is extremely reduced, resulting in the drawback that the head speed cannot be increased as much as expected.

Another method is to add a weight to the inside of the grip, but in this case,
Since the heavy object is located too close to the wrist, which is the center of rotation, the moment of inertia around the wrist is
I ₂ cannot be increased, so a 1 and _{a 2 in} Figure 1
Distance from swing axis O to head at point
P ₁ and _{P 2} are longer than those shown in FIG. 1, and therefore the head speed cannot be increased sufficiently.

In view of the above points, the present invention provides a so-called rate hit that can maintain the angle between the arm and the shaft at the beginning of the swing by protruding the shaft from the rear end of the grip and adding a weight to the shaft in this protruding portion. The purpose of the present invention is to provide a golf club capable of increasing the flight distance of the ball.

Below, some embodiments of the present invention will be described based on the drawings. A head 2 is attached to the tip of the shaft 1, and a grip 3 is attached to the rear of the shaft 1, leaving a protrusion 1a at the rear end. It is being As shown in FIG. 3, a weight body 4 made of lead or other material with high specific gravity is adhesively fixed to the protrusion 1a, and a stopper 5 is fixed to the open end of the protrusion 1a. . When swinging such a club, since there is a weight body 4 behind the grip 3 (i.e. wrist), the moment of inertia I ₂ around the wrist increases, and this changes the angle between the arm and the shaft 1 in the swing. It is possible to maintain a so-called rate hit in the initial stage _of
can be made small, thereby making it possible to increase the angular velocity around the swing axis O, which in combination with the magnitude of the moment of inertia around the wrist can increase the flight distance of a hit ball.

FIG. 4 shows another embodiment. In this embodiment, the weight body 4 is attached inside the protruding portion 1a, thereby making the weight body 4 invisible from the outside. 4 from falling off. Alternatively, the weight body 4 may be attached to both the inside and outside of the protrusion 1a.

The present invention is as described above, and in particular, the shaft protrudes from the rear end of the grip, and a weight body is provided on this protruding shaft, so that the moment of inertia around the wrist increases due to the weight body located at the rear of the wrist. This makes it possible to maintain the angle between the arm and the shaft at the beginning of the swing, making it possible to achieve a so-called rate hit, and since the weight body is located relatively close to the swing axis, the angular velocity around the swing axis can be increased. Therefore, it is possible to increase the head speed of the club and the flight distance of the ball.

[Brief explanation of the drawing]

FIG. 1 is an explanatory view showing the swing plane of a golf swing, FIG. 2 is an overall view of the golf club according to the present invention, and FIG. 3 is an enlarged sectional view taken along the line A-A' in FIG.
FIG. 4 is an enlarged sectional view taken along the line AA' in FIG. 2 in another embodiment. 1... Shaft, 1a... Shaft protruding from the rear end of the grip, 3... Grip, 4... Weight body.

Claims (1)

[Scope of Claims] 1. A golf club in which a grip 3 of a golf club shaft is extended and protruded from the rear end thereof, and a weight body 4 is arranged and fixed to this protruding shaft portion 1a. 2. The golf club according to claim 1, wherein the weight body 4 is arranged and fixed on the outer peripheral surface of the protruding shaft 1a. 3. The golf club according to claim 1, wherein the weight body 4 is arranged and fixed inside the protruding shaft 1a.