JPH0482574A - Wood club head for golf - Google Patents

Abstract

PURPOSE:To reduce the rigidity of a crown surface without reducing the thickness of the crown surface by corrugating the crown surface of a head body formed of a metal or FRP with the wave length in the ball driving direction. CONSTITUTION:A head body 1 of a wood club for golf has a super-plastic alloy shell structure made of stainless steel, aluminum alloy or magnesium alloy and formed of a face surface 2, back surface 3, sole surface 4, crown surface 5, toe side surface 6, heel side 7 and hosel part 8 to which a shaft S is mounted. The whole crown surface 5 of the head body 1 is formed with a corrugated part 51 producing the progress of wave motion in the ball driving direction to reduce the rigidity of the crown surface 5 in the ball driving direction. Thus, when a ball is driven by the face surface 2 of the head body 1, while an initial ball driving angle is enlarged, the locus of a ideally large trajectory with few lofty fly is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a golf wood club head in which the entire head is made of an outer shell structure such as metal or fiber-reinforced plastic (FRP). The ball's flight distance is increased by making the surface less rigid.

[Prior Art] Conventionally, in this type of golf wood club head, for example, in a metal wood club head in which the entire outer shell of the head is made of stainless steel, aluminum alloy, magnesium alloy, etc., the face surface of the head body (facing the ball hitting direction) Front surface: ball hitting surface), sole surface (bottom surface), back surface (rear surface facing the ball hitting direction), crown surface (top surface), toe side (front surface facing perpendicular to the ball hitting direction), and heel side (
The rear surface (facing perpendicularly to the direction of ball hitting) is formed continuously and integrally, and in particular, the other surfaces except the face surface are formed into smooth curved surfaces, while the face surface is formed into a substantially flat surface, A plurality of horizontal grooves are usually provided in order to provide a predetermined loft angle depending on the club count and to improve directionality due to the spin effect on the ball when hitting the ball.

In addition, such traditional metal wood club heads,
Because the face surface of the head body is set to a unique loft angle depending on the count, the larger the loft angle, the more
While the advantageous hitting angle increases in order to extend the flight distance of the ball, the backspin applied to the ball also increases.
The run (roll) decreases, which has the opposite effect on extending the flight distance of the ball.Especially, when the ball is hit by a headwind, the ball tends to fly up a lot. cannot be expected.

Therefore, in order to eliminate the above-mentioned problems with the metal wood club head of the conventional structure, the crown surface of the head body was made thinner than the other main body parts to make it less rigid.
It has been proposed to make the ball more flexible in response to impact when hitting the ball, thereby increasing the flight distance of the ball even if the loft angle of the face is fixed.

[Problems to be Solved by the Invention] However, the above-mentioned conventional metal wood club heads are molded by casting, and in particular, the crown surface of the head body is a smooth curved surface with no unevenness. In order to reduce the rigidity by reducing the thickness to 1 mm or less after casting, the current practice is to reduce the thickness by polishing.

This increases manufacturing costs.

Moreover, if the crown surface of the head body is made extremely thin,
It is easily dented by external forces other than those caused by hitting the ball, and a sufficient amount of deflection cannot be obtained when hitting the ball, making it impossible to increase the flight distance of the ball.

On the other hand, in a wood club head where the entire head outer shell is made of FRP, thinning the crown surface of the head body in order to reduce the rigidity has a negative effect on the strength and rigidity of the entire head.

[Object of the Invention] An object of the present invention is to provide a wood club head for golf in which the rigidity of the crown surface of the head body can be reduced without reducing the thickness of the crown surface. be.

[Means for Achieving the Object] In order to achieve the above-mentioned object, the present invention provides at least a portion of the crown surface of the head body having an outer shell structure made of metal or FRP, so that the ball hitting direction is the wavelength direction. The structure is formed into a wave shape.

[Structure of the invention] Hereinafter, the configuration of the present invention will be explained based on the drawings.

As shown in FIG. 2, reference numeral 1 in the figure is the head body of the golf wood club according to the present invention.

The head body 1 has an outer shell structure made of a superplastic alloy such as stainless steel, aluminum alloy, or magnesium alloy, and includes a face surface 2, a back surface 3, a sole surface 4, a crown surface 5, a toe surface 6, and a heel surface. It consists of a side surface 7 and a hosel portion 8 to which the shaft S is attached.

As shown in FIG. 1, the entire surface of the crown surface 5 of the head body 1 is formed into a corrugated portion 51 having a corrugated shape such that the ball hitting direction X is the traveling direction (wavelength direction) of the wave. .

[Function] In other words, in this invention, since the crown surface S of the head body 1 is formed in the waveform 51 with the wavelength direction in the ball hitting direction X, the rigidity of the crown surface 5 of the head body 1 in the ball hitting direction X is increased. It gets lower.

As a result, as shown in Fig. 3, when the ball B is hit with the face surface 2 of the head body 1, the initial hitting angle increases as shown by the solid line in Fig. 3. This makes it possible to obtain the trajectory of the trajectory, which allows the flight distance of ball B to be significantly extended, and since the backspin of ball B is small after falling to the ground G, it is possible to make a long run. is obtained.

Note that the dotted line shown in FIG. 3 indicates the trajectory of the trajectory of the head of the conventional structure.

Incidentally, such behavior of the ball B can be understood from the measurement results of how backspin is applied to the ball B when the ball is hit, which will be described below.

That is, first, so that the rotational state of ball B is known,
Draw several lines on the circumferential surface of ball B to serve as landmarks, like longitude lines on a globe.

Then, while illuminating this ball B with a strobe with a continuous emission time interval of 2 milliseconds, the ball B at the time of hitting the ball is
By taking a photograph of the ball B, it is possible to quantitatively measure the rotational speed of the ball B immediately after it starts flying due to the impact of the club head.

According to these measurement results, the ball B is attached to the head body 1.
Flight distance immediately after leaving face 2 of 200 m
The rotation angle of the ball while moving m was 29.0' in the conventional head, but was reduced to 21.5' in the head of the present invention. Note that the direction of rotation of the ball B in this case is such that the moving speed of the lower surface of the ball B is greater than the moving speed of the upper surface of the ball B, which is called "backspin." be.

Although the behavior of the golf club head according to the present invention when hitting a ball has not necessarily been fully elucidated, it is presumed that the behavior shown in FIG. 4 occurs.

Figure 4 (A) shows the behavior at the time of impact. When the ball B is hit with the face 2, the corrugated portion of the crown surface 5 moves in the direction of the ball as shown by the two-dot broken line in Figure 4 (A). The face surface 2 is elastically contracted and deformed with respect to X, and the face surface 2 rotates at an inclination θ toward the rear using the bottom point a as a fulcrum, returning to the original fixed loft angle θ. Increase (θ10.

), elastic energy is stored.

In this state, when the ball B attempts to leave the face surface 2, as shown in FIG. Due to the elastic energy, the corrugated portion of the crown surface 5 elastically expands in the ball hitting direction X, and the face surface 2 elastically rotates forward about the bottom point a to restore its original direction.

Due to the rotation due to the elastic restoring force of the face surface 2.

It is presumed that the amount of backspin applied to the ball B is suppressed, and as a result, an ideal trajectory trajectory as shown by the solid line in FIG. 3 is obtained.

In this case, the wavelength of the corrugated portion 51 formed on the crown surface 5 of the head body 1 is 40-170 mm, preferably 60 mm.
-170 mm, the amplitude T is 2 to 40 mm, preferably 10 to 40 mm, and is formed with more than 0.5 cycles, and the ratio relationship between this wavelength and the amplitude T is 10:1 to 1.
:1, preferably 8:1 to 2=1.

[Example] In the present invention, the head main body 1 has been described using a metal outer shell structure, but similar functions and effects can be obtained with an FRP outer shell structure.

Further, in this invention, the crown surface 5 of the head body 1
The same action and effect can be obtained even if only a part of the waveform portion 51 is formed.

[Effects of the Invention] As is clear from the above description, the present invention has the crown surface of the head body having an outer shell structure made of metal or FRP formed into a waveform with the direction of ball hitting being the wavelength direction. It is possible to accumulate elastic energy on the face, increase the loft angle of the face, and use the restoring force of the elastic energy of the face to rotate the face forward when one ball leaves the ball. In addition, the initial ball hitting angle is increased, an ideal long trajectory with little fly-up can be obtained, and the flight distance of the ball can be significantly extended.

This also reduces the backspin of the ball, which allows for a greater run after it hits the ground.

Furthermore, if the present invention is applied to a metal wood club head, the rigidity of the crown surface can be reduced without reducing the thickness of the crown surface.

A wood club head for golf that has excellent effects such as reducing manufacturing costs as there is no need for polishing after casting, and there is no negative effect on the overall strength and rigidity of the club head. This is something that can be provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a golf wood club head according to the present invention. FIG. 2 is an external perspective view of the head body. FIG. 3 is an explanatory diagram showing the trajectory of the ball when hitting the ball in comparison with a conventional ball, and FIGS. 4(a) and 4(b) are explanatory diagrams showing the behavior of the club head when hitting the ball. 1... Head body, 5... Crown surface, 51...
・Waveform part, X...Ball direction.

Claims (1)

[Claims] (1) A wood club head for golf, characterized in that at least a portion of the crown surface of the head body having an outer shell structure made of metal or FRP is formed into a waveform with the hitting direction as the wavelength direction.