JPH04180778A - Golf club head - Google Patents

Abstract

PURPOSE:To increase the flying distance of a ball by forming a long recessed groove in the direction being roughly parallel to the hitting face surface of the golf club head on almost the top part of the curved surface formed on the top surface of the head. CONSTITUTION:On almost the top part P of the top surface 4 of a golf club head 7 of a wood type a long recessed groove 8 is formed in the direction being roughly parallel to the face surface 2 of the head 7. As a result, a position peeling off from the top surface of air flowing along the top surface 4 moves backward, comparing with a conventional one. That is, air which goes into the rear part of the recessed groove 8 whirls around, and joins with an air flow of the upper part from the front part of the recessed groove 8, therefore, a flow of the air flow increases, a pealing position moves backward, and an air resistance decreases. Accordingly, the air resistance of the club head 7 can be decreased. In such a away, a swing speed of the head 7 can be increased, and the flying distance of a ball can be increased.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a wood type golf club head, and in particular, to a wood type golf club head that has less air resistance during swing and can increase the distance of a hole. be.

[Traditional technique (hoi)]

In order to increase the flight distance of a golf ball, it is necessary to increase the swing speed of a wood-type golf club, and in order to do so, it is necessary to reduce as much as possible the air resistance that occurs on the golf club head that moves at high speed. Must be.

As a conventional technique for reducing the air resistance of a wood type golf club head, there is a technique described in Japanese Utility Model Application Publication No. 128664/1983.

According to this technology, the shape of the tip part and the sole part of the head body are made into an isosceles triangular shape, and the shape of the entire head body is made into a flat bullet shape to reduce the air resistance of the head body. Furthermore, a neck portion is provided in the heel portion.

However, there is a limit to reducing the thickness of the head by making the head shape flat, and it is not expected to be very effective in reducing air resistance.

The amount of air resistance produced by a wood type golf club head can be indirectly determined by the difference in air pressure between the front and rear of the golf club head. You can tell by the flow of air around you.

[Problem to be solved by the invention]

In FIG. 6, the head 1 of a conventional Wundquip -I golf club is not shown by arrow F, but the swing direction ad=cut 1j.
J'i is i (I cross-section times, and the outline of Heno 1-1 is
A substantially planar face surface 2 that is a ball hitting surface, and a curved top surface 4 that becomes the upper surface when hitting the ball and connects to the rear end 3.
, a substantially planar lower surface 5 on the opposite side of the top surface 4 , and a curved rear lower surface 6 connected from the lower surface 5 to the rear end portion 3 .

A model 1' with the same shape as this head 1 was installed in a wind tunnel,
When air is rectified and blown in the opposite direction of arrow F,
As shown in FIG. 7, the air flow separates from the top surface 4 at a position past the top P' of the 1.7 surface 4, and behind it the air becomes turbulent -ζ spiral.

Since the lower surface 5 is flat, the leading edge Q at the tip of the lower surface 5 is spaced 11 times away from the air, creating a thick resistance.

By reducing these air turbulences, it is possible to reduce the air resistance.

The present invention reduces the turbulence of the air flow backward from the top P' of the top surface 4, and increases the speed of the I-1 by 1-1. It is something.

[Means for Solving the Problem] In order to achieve the stated purpose, in the F-type golf club F', a golf club is attached almost to the top of the curved surface formed on the top surface of No.1. A long concave groove is formed in a direction almost parallel to the face surface for hitting Hemet.

Alternatively, the lower surface may have a curved shape with a swollen central portion.

[For production]

The knot-type golf club head configured as described above allows air to enter the groove provided almost at the top of the top surface of the helenoid 1, and this air resists the airflow flowing along the top surface. ' Reduces air turbulence behind the top.

Thus, the air resistance of the golf club head can be reduced.

1-In addition to providing a concave groove near the top of the bump surface, if the bottom surface is made into a curved shape with a bulge in the center, there will be less air resistance on the bottom surface, which will improve the shape of the golf club head. Air resistance can be further reduced.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a vertical cross-sectional view of a Usoto type golf club head (■) cut in the swing direction, not indicated by the arrow F, and the outline of the head 7 is the same shape as the ring λI (of the conventional head 1, A shaped face surface 2, a curved top surface 4 connected to the rear end 3, a (, f planar lower surface 5, and a curved rear lower surface 6 connected from the lower surface 5 to the rear end 3). Or, an elongated concavity 148 in a direction substantially parallel to the face surface is formed at approximately the apex P of the top surface 4 (see Fig. 2).
.

When model 7', which has the same shape as head 7, was tested in a wind tunnel, the third
As shown in the figure, the position where the air flowing along the top surface 4 separates from the top surface 4 is located at the rear (compared to the conventional one).
Left side) Move.

The reason for this is that, as shown by the chain line in FIG.
The air that entered the rear (left side) swirls along the concave groove 8,
It is thought that since the front part of the groove 8 merges with the air flow above, the flow of the air flow increases, the separation position moves to the rear (left side), and the air resistance decreases.

The air pressure to the point in front of model 1' and model 7' is P
1, the air pressure at the point B in the back is P2, the viscosity coefficient is ρ, and the wind speed is ■, then the pressure coefficient Cp is as follows.

Table 1 shows the pressure coefficient Cp of model 1' at each wind speed (3), and Table 2 shows the pressure coefficient Cp of model 7'.

Comparing Tables 1 and 2, it can be seen that the pressure coefficient iCp of the model 7' having the groove 8 is improved by about 10%.

FIG. 4 is a longitudinal cross-sectional view of a wood-type golf club according to a second embodiment of the present invention, cut in the swing direction, not indicated by the arrow r, and showing the shapes of the F surface 5 and the rear lower surface 6 at the center. It is the same as the golf club hen door of the first embodiment except that the lower surface 10 has a gently curved surface with a bulged portion.

When a model 9' having the same shape as head 9 was tested in a wind tunnel, the seventh
As shown in the figure, the air flowing not only along the top surface 4 but also along the bottom surface 10 flows in a rectified state, so as shown in Table 3:
5%, which is an improvement of about 20% over model 7'.

[Effects of the Invention] Since the present invention is configured as described above, it produces the following effects.

(1) By forming a long concave groove in a direction almost parallel to the hitting face of the golf club head at almost the top of the curved surface formed on the top surface of the throat of a wood type golf club, Since it is possible to reduce the air resistance of 1- and imitate the swing speed of 1-, the flight distance of the pole can be increased.

(2) A long concave groove is formed approximately at the top of the curved surface formed on the 1-tube surface in a direction approximately parallel to the hitting face and face of the golf club spatula 1, and the shape of the bottom surface is adjusted to the center. If the ball has a curved shape with a bulging portion, the air resistance on the lower surface of the head can be reduced, so that the flight distance of the ball can be further increased.

[Brief explanation of drawings]

Figures 1 to 5 show embodiments of the present invention, the first being a longitudinal cross-sectional view of a wood type golf club spatula, the second being a perspective view of a wood type golf club head, and the third being a longitudinal cross-sectional view of a wood type golf club head. 1 is a front view showing the air flow in a wind tunnel test of a head model with the same shape as in FIG. 1, FIG. 4 is a vertical cross-sectional opening of the golf club head of the second embodiment, and FIG. 5 is the same shape as in FIG. 4. Figure 6 is a vertical IJfr view of a conventional wood-type golf club head, and Figure 7 is a front view of a head model with the same shape as Figure 6. FIG. 3 is a front view showing the flow of air in a model wind tunnel experiment. 2... Face surface, 4... River/pull surface, 5... Lower surface, 6... Rear lower surface, 7... Head, 7'... Model, 8... Concave groove, 9... ...Hera 1ζ, 9'...Model, P, P'...Top.

Claims (2)

[Claims] (1) A wood type golf club head, characterized in that a long concave groove is formed approximately at the top of the curved surface formed on the top surface of the head in a direction approximately parallel to the hitting face surface of the golf club head. golf club head. (2) In a wood-type golf club head, a long concave groove is formed approximately at the top of the curved surface formed on the top surface of the head in a direction approximately parallel to the hitting face surface of the golf club head, and the shape of the bottom surface is A golf club head characterized by having a curved shape with a bulged central portion.