JPS6229065B2 - - 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 P ₀ becomes smaller as the swing draws a shorter arc, and 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 makes it difficult for the wrist to rotate, making it 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
₀ and ₂ are longer than those shown in FIG. 1, and therefore the head speed could not be increased sufficiently.

In view of the above points, the present invention integrally forms a stepped portion at the rear end of the grip, and by providing a weight body inside this stepped portion, the angle between the arm and the shaft is adjusted at the initial stage of the swing. It is an object of the present invention to provide a golf club that can maintain a so-called rate of hit, thereby increasing the flight distance of the ball.

Several embodiments of the present invention will be described below with reference to the drawings. A head 2 is attached to the tip of a shaft 1, and a cylindrical grip 3 is inserted and fixed to the rear end of the shaft. The grip 3 is made of natural rubber as a main component and is vulcanized, and has a stepped portion 3b integrally formed at the rear end following a grip portion 3a for gripping the club.

FIG. 3 shows a first embodiment of the present invention, in which a stepped portion 3b having a smaller diameter than the grip portion 3a is formed at the rear end of the grip 3, and inside this stepped portion 3b there is lead or other metal. A weight body 4 made of a material with high specific gravity such as tungsten is integrally incorporated during vulcanization molding. Therefore, when swinging a club with such a configuration, since the weight body 4 is located behind the grip portion 3a (that is, the wrist), the moment of inertia _I2 around the wrist increases in the swing plane shown in FIG. This makes it possible to maintain the angle formed by the arm and the shaft 1 at the beginning of the swing, which is what is called a rate hit. Moreover, since the weight body 4 is located at a short distance from the swing axis O, the moment of inertia _I1 around the swing axis O can be reduced, thereby increasing the angular velocity around the swing axis, and the moment of inertia I around the wrist mentioned above can be reduced. Combined with the size of ₂ , it is possible to increase the flight distance of a hit ball.

FIG. 4 shows another embodiment, and in this embodiment as well, the stepped portion 3b is replaced by the grip portion 3a.
The weight body 4 has a smaller diameter than the stepped portion 3b.
It is inserted into a blind hole 3c formed inside and closed and fixed with a plug body 5. Therefore, in this embodiment, after the club is formed, by appropriately selecting a weight body 4 of a desired weight and inserting it into the blind hole 3c, it becomes possible to freely select the weight of the weight body 4. .

In yet another embodiment shown in FIG. 5, the end of the shaft 1 extends into the stepped portion 3b, and the weight body 4 is inserted and fixed into the extended portion of the shaft. Therefore, in this embodiment, the weight body 4 can be firmly fixed using the shaft 1, and the stepped portion 3b of the grip 3 can also be reinforced by the shaft 1 inside.

The present invention is as described above, and in particular, a stepped portion is integrally formed at the rear end of the grip, and a weight body is provided inside this stepped portion, so that when a player grasps the grip and swings, The moment of inertia around the wrist increases due to the weight inside the stepped part located behind the wrist, which 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. Because the body is located relatively close to the swing axis, it is possible to increase the angular velocity around the swing axis, which in turn increases club head speed and increases ball flight distance. Due to the presence of the attachment part, it is possible to always hold the grip in front of the weight body while swinging, so that the above-described effects of the present invention can be reliably achieved.

Furthermore, since the weight body is covered with the same flexible material as the grip, even if the rear end of the grip hits the belly during swinging, there is no pain. Furthermore, since the stepped part has a smaller diameter than the grip part, it does not take up much space when storing golf clubs in the carrying bag. can do.

[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 FIGS. 3 to 5 are enlarged sectional views taken along the line A-A' in FIG. There are several embodiments of the present invention. 1... Shaft 1, 2... Head, 3... Grip, 3b... Stepped portion, 4... Weight body.

Claims (1)

[Claims] 1 In a golf club in which a head 2 is attached to the tip of a shaft 1 and a cylindrical grip 3 is inserted and fixed to the rear end of the shaft 1, the rear end of the grip 3 is extended to form a step made of the same material as the grip 3. The attached portion 3b is integrally formed, the stepped portion 3b has a smaller diameter than the grip portion 3a, and a heavy body having a weight sufficient to increase the moment of inertia around the wrist during swing is provided inside the stepped portion 3b. A golf club that contains 4 in a sealed manner.