JPH08112378A - Golf club set - Google Patents

Abstract

PURPOSE: To easily loft a ball with a long iron and make the ball easy to stop on a green with a short iron by setting the height of the center of gravity of a club with a number whose loft angle is specific and increasing the height of the center of gravity as the club number increases. CONSTITUTION: The head 1 of a golf club in an iron group includes a hosel 2 connected to the lower end part of a shaft 10 and the lower end part of the hosel 2 is equipped with a face 3, a sole part 4 which extends from the heel to the toe in a plane nearly parallel to the ground surface when the golf club is addressed and a rib 6 at the periphery of a hollow 5 formed in the center part of the reverse surface of the head 1. Then flow is formed so that the gravity center height of the head 1 increases with the club number, and the height of the center of gravity of a club whose loft angle is 27 deg.±3 deg. is 19±13mm. For this flow, a load thick part 8 is formed in the hollow 5 closely to the rib 6 on the side of a top edge 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an iron type golf club set in which the loft angle is increased in a predetermined order as the count increases.

[0002]

2. Description of the Related Art A conventional iron-based golf club set has nine pitching wedges (PW) and sand wedges (SW) added to the third to ninth pitching sands (or pitching sands between PW and SW). A set of 10 pieces, which includes what is called PS) or an approach wedge, is general. In such a set, the loft angle is increased in a predetermined order as the count increases. As a typical example of setting the loft angle, 1st ... 18 °, 2nd ... 2
0 °, 3rd ... 22 °, 4th ... 25 °, 5th ... 28 °, 6
Number ... 32 °, 7th ... 36 °, 8th ... 40 °, 9th ... 44
, PW ... 48 °, PS ... 53 °, SW ... 57 °. The loft angle of each of these numbers has a difference of about ± 3 ° depending on the set example. And the point where the total force of the weight acting on the head is gathered, and as a position to measure the balance, that is, one that considers the center of gravity as a whole set, one designed to be the center of the face in all counts and all counts The one designed to have a low center of gravity is known. Such all-counters having a low center of gravity are mainly intended to realize high trajectory flight with easy ball raising.

[0003]

In the conventional set, there is no flow system relating to the position of the center of gravity in the vertical direction. For example, in a set designed to have a lower center of gravity of all numbers, it is difficult to increase the spin rate of the ball with a short iron. , The ball stopped on the green was getting worse.
With a general PW, the head weight is about 294 g, and the height of the center of gravity is 18.1 mm. When the ball of the thread-wound balata cover is hit with this PW at a head speed of 40 m / s, 90
It was 60 rpm. Further, in the case of PW having a low center of gravity, the spin amount was further reduced even if the flight distance could be increased, and the ball was hard to stop on the green.

Therefore, an object of the present invention is to provide a golf club set in which a ball can be easily raised with a long iron and a spin amount can be increased with a short iron so that the ball easily stops on the green.

[0005]

In order to achieve the above-mentioned object, the present invention provides a loft angle of 27 ° ± 3 ° in an iron type golf club set in which the loft angle is increased in a predetermined order as the count increases. The center of gravity height HG is set to 19 ± 3 mm in the No. club, and the center of gravity height HG is set to increase as the number of clubs increases. In a preferred embodiment, the height HG of the center of gravity of a club having a loft angle of 40 ° or more is set to 21 ± 3 mm or more, more preferably 21 ± 1 mm or more.

[0006]

In the present invention, since the flow system of the position of the center of gravity in the vertical direction is adopted, the height of the center of gravity becomes lower as the long iron becomes easier to raise the ball, and the height of the center of gravity becomes higher as the short iron becomes higher in the spin amount of the ball. Increase,
The ball is easier to stop on the green. Center of gravity height 21.
The spin rate when hitting a ball of a thread-wound balata cover with a head speed of 40 m / s with a PW of 1 mm is 9700 rpm.
Met. 64 compared to the spin amount of the above-mentioned general PW
An increase in spin rate of 0 rpm was observed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings.

1 and 2 show a head 1 of an iron type golf club to be set. The head 1 includes a hosel 2 connected to a lower end of a shaft 10, and the lower end of the hosel 2 is a face surface. 3, a sole portion extending from the heel to the toe in a plane substantially parallel to the ground when the golf club is addressed 4, a recess 5 provided in the center of the back surface of the head 1, that is, a cavity, provided around the recess 5. The rib 6 is provided. In a set of a plurality of golf clubs having the so-called cavity back type iron type head 1 shown in FIGS. 1 and 2, the head 1 is caused to flow so that the height of the center of gravity of the head 1 increases as the count increases. Loft angle 27 at this time
The height of the center of gravity of a club with a count of ° ± 3 ° (especially with a 5-iron) is 19 ± 3 mm, preferably 19 ± 1 mm. As an example of how to perform such a flow, a weighted portion 8 is provided in the recess 5 near the rib 6 on the side of the top edge 7. The weight of the weighted portion 8 is increased as the count increases. The long iron does not require such a weighted portion 8. In addition, the center of gravity can be changed from the toe side to the heel side by adjusting the amount of the ribs 6 on the toe side. As another example of the means for causing the height of the center of gravity to flow, not only the amount of weight of the portion shown in FIG. 2 but also the amount of weight of the portion of the top edge 7, that is, the meat at the portion of FIG. 2 is adjusted. The height of the center of gravity can be made to flow by adjusting the amount of weight applied, or by adjusting the amount of weight added at the sole portion 4, that is, the portion shown in FIG. 2 or by adjusting the amount of weight added at the portion shown in FIG. Of course, it is also possible to make the flow by combining the adjustment of the amount of meat.
Alternatively, in a head called a composite club, which is a combination of different materials, the height of the center of gravity can be made to flow by using materials having different specific gravities.

The height of the center of gravity means the line (Z axis) perpendicular to the face surface 3 from the position of the center of gravity G of the head 1 as shown in FIG. It means the height HG between the intersecting position and the sole portion 4. Further, when a line (Z axis) orthogonal to the face surface 3 is drawn from the center of gravity G, the distance from the center of gravity G to the face surface 3 is defined as the center of gravity depth Z.
It is called G. Further, the position of the center of gravity G and the height between the sole portions 4 are called HGR, and the distance between the Z axis and a line passing through the leading edge 9 and parallel to the Z axis is called the center of gravity distance YG. Further, a line parallel to the face surface 3 passing through the center of gravity G and penetrating the plane of the drawing of FIG.
A straight line that passes through and is parallel to the face surface 3 and perpendicular to the X axis.
When the Z axis is a straight line that is perpendicular to the X axis and the Y axis and passes through the center of gravity G, the moment of inertia about the X axis is IX,
The moment of inertia about the Y axis was defined as IY, and the moment of inertia about the Z axis was defined as IZ. In the case of the conventional general PW, each of these values is head weight 294.3g, YG23.2m.
m, ZG0.3mm, HG18.1mm, HGR17.8m
m, IX 10.2 g · mm · sec ² , IY 27.4 g · mm · s
ec ² and IZ 30.0 g · mm · sec ² . The PW in the set example of the present invention has a head weight of 294.1 g, Y
G29.8mm, ZG0.7mm, HG21.1mm, HGR
20.6 mm, IX13.2 g · mm · sec ² , IY27.8
g · mm · sec ^2, was IZ32.5g · mm · sec ^2. In addition, both of these PWs were cast stainless steel and were plated with ordinary nickel. As a result of trial hitting a ball of a thread-wound balata cover (our J's balata) with these two PWs (head speed 40 m / s), it was 9 with the conventional general PW.
The backspin was 060 rpm, whereas the PW of the set of the invention was 9700 rpm. Since the height of the center of gravity is 3 mm higher than that of the conventional PW, it is considered that the distance between the hit point and the position of the center of gravity becomes large, and the difference in this distance affects the spin. FIG. 4 is a diagram for explaining the gear effect between the ball and the face surface 3 at the time of impact. When the ball is hit, the ball is rotated in the direction of the arrow, that is, backspin, and the head 1 moves toward the top edge 7 side. Try to rotate in the direction of the arrow.

The mark □ in the graph shown in FIG. 5 shows an example of the embodiment set of the present invention, and shows the center of gravity height HG in each count. The mark Δ indicates the center of gravity height HG of each count in the conventional set example. In the embodiment of the present invention, the loft angle is 27 ° ± 3 °, for example, the center of gravity height HG is set to 19 ± 1 mm in a club with a 5 iron, and the center of gravity height HG is set to increase as the count increases. There is. Further, in the PW, the center of gravity height HG was set to 21.1 ± 1 mm, as described above, and for the 9th iron, set to 20.09 mm. Generally, the height of the center of gravity HG
Is preferably set to increase by about 0.25 ± 0.1 mm for each count, but may be changed slightly depending on the set.

[0011]

As described above, according to the present invention, the height of the center of gravity is set to increase as the count increases, so that the ball tends to rise with a long iron and the spin amount increases with a short iron. The ball will easily stop on the green. In particular, a short iron shorter than the 5th iron can give a larger backspin amount than a conventional club, and the ease of stopping the ball on the green is remarkable.

[Brief description of drawings]

FIG. 1 is a perspective view of an iron golf club head used in the set of the present invention, as viewed from the back side.

FIG. 2 is an end view of FIG. 1A-A line.

FIG. 3 is a diagram illustrating the height of the center of gravity.

FIG. 4 is a diagram illustrating a gear effect.

FIG. 5 is a graph showing the height of the center of gravity of each count of a conventional golf club set and the height of the center of gravity of an embodiment of the present invention.

[Explanation of symbols]

 1 head 3 face surface HG center of gravity height G center of gravity

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Masaomi Ebisa 45 Kanda Higashi Matsushita-cho, Chiyoda-ku, Tokyo Inside Bridgestone Sports Co., Ltd.

Claims (2)

[Claims] 1. An iron-type golf club set in which the loft angle is increased in a predetermined order as the iron count is increased, and the center of gravity height HG is set to 19 ± 3 mm for a club with a loft angle of 27 ° ± 3 °. , A golf club set in which the center of gravity height HG increases as the count increases. 2. The golf club set according to claim 1, wherein a club having a loft angle of 40 ° or more has a gravity center height HG of 21 ± 3 mm or more.