JPH04180779A - Golf club head - Google Patents

Abstract

PURPOSE:To increase the flying distance of a ball by forming a recessed groove in the rear part of the opposite side of the face surface of the hitting surface of the golf club head of a wood type. CONSTITUTION:On the rear part of a golf club head 7 of a wood type, a recessed groove 8 formed by notching the rear end side of the top surface 4 and the rear end side of the lower face 6 of the rear part is provided. As for a cross section shape of the recessed groove 8, roughly a square is allowable as indicated with a full line, and also, a curve shape is allowable as indicated with a one-point chain line. The recessed groove 8 is long in the direction being roughly vertical to the swing direction, and both its end parts are joined gently to the surface of the head 7. In such a way, when the golf club is swung, an air resistance of the head 7 decreases, 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 throat, and in particular, it has low air resistance during swing and can increase the flight distance of the ball. It is possible.

C. Prior Art] 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 increase the air resistance generated on a golf club head that moves at high speed. must be reduced as much as possible.

As a conventional technique for minimizing 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 the same technology, the shape of the top part and the sole part of the Hen 1 body are made into an isosceles triangular shape, and the shape of the whole head body is made into a flat bullet shape to reduce the air resistance of the head body. A neck part is provided in the heel part.

However, there is a limit to reducing the thickness of the head by flattening the head shape, and the effect of reducing air resistance cannot be expected to be very effective.

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 Colts Club Heno 1, and when visually observed, the amount of air resistance produced by a wood-type golf club head can be determined by checking the air resistance of the club head placed in a wind tunnel. This can be determined by the air flow around the area.

[Problems to be Solved by the Invention] Figure 5 shows the hem 1 of a conventional wood type golf club.
-1 is a vertical cross-sectional view taken in the direction of swing force indicated by arrow F, and the contour of the head 1 includes a substantially planar face 2 that is solid when hitting the hole, and a rear end 3 that becomes two sides when hitting the ball. It is constituted by a curved top surface 4 that is connected to the top surface 4, a lower surface 5 that is approximately 1'-shaped on the opposite side of the top surface 4, and a curved rear lower surface 6 that is connected from the lower surface 5 to the rear end portion 3.

Model 1', which has the same shape as the Het River, was installed in a wind tunnel.
When air is rectified and blown in the opposite direction of arrow F,
As shown in Fig. 6, the air flow above the tip face 4 separates from the lug face 4 at a position past the top P, and the air flow below the lower face 5 is caused by the leading edge of the lower face ◇:i. Edge Q
This causes the air to separate, and the air downstream of the abrasion becomes turbulent.
\It becomes a spiral behind the throat.

If these air turbulences are reduced by θ&, the air resistance of the river can be reduced.

The present invention aims to increase the speed of the head 1 by reducing air turbulence behind the head 1'.

[Means to solve the problem]

In order to achieve the above object, a groove is formed in the wood type golf club hem 1 at the rear part of the golf club hem opposite to the blade surface.

1 Effect] The Colts club head configured as described in - reduces the air resistance behind the air shaft 71 in the concave hole when the Colts club moves at high speed in the air by swinging.

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

FIG. 1 is a plan view of the golf club head 7 of Run 1 Quizo, and FIG. 2 is a 1-square section cut along the X-χ cross section parallel to the swing direction.

In FIG. 2, the outline of the head 7 is different from that of the conventional example.
A groove 8 is provided at the rear end of the top surface 4 and at the rear end of the lower rear surface 6.

The cross-sectional shape of the groove 8 may be approximately square as shown by the solid line in FIG. 1, or may be curved as shown by the dashed line.

As shown in FIG. 1, the groove 8 is long in a direction substantially perpendicular to the swing direction, and both ends thereof smoothly connect to the surface of the head 7.

When a wind tunnel test was conducted on Model 7', which has the same shape as Hendoma, the third
As shown in the figure, the separation point between the model 7' and the air flowing along the top surface 4 and the bottom surface 5 has moved backward, and the air flow is now flowing in a V shape.

The reason for this is thought to be that the air entering the concave 'li4B creates less swirling of the air behind the model 7'.

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

Table 1 shows the pressure coefficient Cp of model 1' and Table 2 shows the pressure coefficient Cp of model 7' for each wind speed.

Comparing Tables 1 and 2, model 7' having the concave grooves 8 has a significantly better pressure coefficient CP, and the air resistance when swinging the golf club is greatly reduced.

FIG. 4 is a vertical cross-sectional view of a Uso-type golf club head showing another embodiment of the present invention taken along a plane parallel to the swing, and shows a tip on the rear side of the top surface of the conventional hand 1. 10, and a concave groove 8' is formed at the rear of the head 1.

The material of the chip may be either metal or non-metal, and it is attached to the hem 1"1 by adhesive or other means.

The concave groove 8' also has the same effect as the above-mentioned first example hIt.

〔Effect of the invention〕

Since the invention chamber is configured as described above, when the golf club is swung, the air resistance of the golf club is reduced, so that the flight distance of the ball can be increased.

[Brief explanation of drawings]

1 to 4 show embodiments of the present invention, the first is a plan view of a wood type golf club head, the second is a sectional view taken along line XX in FIG. 1, and the third is a first A vertical cross-sectional view showing a wind tunnel test of a head model with the same shape as the figure, Figure 4 is a vertical cross-sectional view showing another embodiment of the golf club head, and Figure 5 is a vertical cross-sectional view of a conventional wood type golf club head. Figure 6 is a longitudinal sectional view showing a wind tunnel experiment of a head model with the same shape as in Figure 4. 2... Face surface, 4... Top surface, 5... Bottom surface, 6... Rear lower surface, 7... Head, 7'... Model, 8, 8'... Concave groove, 10... Chip.

Claims (1)

[Claims] 1. A wood-type golf club head, characterized in that a concave groove is formed at the rear of the hitting surface of the golf club head on the opposite side from the face surface.