JPS6348292Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement in an iron club set, and in particular, attempts to stabilize the directionality of the ball by improving the back design portion of the iron head.

In golf play, iron clubs are commonly used as a set. The iron club set consists of long irons, which are generally used for long-distance hits with long club lengths and small loft angles, and long irons, which are generally used for short-distance hits with short club lengths and large loft angles. It consists of short irons, which are used for short irons, and middle irons, which have characteristics such as medium length and loft angle, and are used for medium-distance hitting. When using an iron club set, the probability of being hit at the sweet spot of each club decreases as the club length gradually increases from short irons to long irons.

In a conventional iron club set, the back design of the head is the same even though the club lengths of each club are different, and the sweet spot of each club is almost the same width. As you change from short irons to long irons, the probability of hitting the ball at the sweet spot decreases, which has the disadvantage that, especially for beginners, the directionality becomes less stable the longer you go from short irons to long irons. On the other hand, a means for enlarging the sweet spot of the head of an iron club is known from Japanese Utility Model Publication No. 53-288. However, if this method is applied to each club in an iron club set, the effect of improving the direction of ball flight with long irons compared to the conventional method can be obtained, but with short irons it is the same as with long irons. If the sweet spot of the ball is widened, a problem arises in that it becomes difficult to control the delicate flight distance of the ball.

In other words, the flight distance of the ball decreases as the ball's impact position moves away from the center of the sweet spot area on the face of the head, but if the range of the sweet spot is narrow, the impact position moves away from the center of the sweet spot area. As a result, the flight distance of the ball decreases significantly. However, when the range of the sweet spot is wide, even if the hitting point moves away from the center of the sweet spot area, the flight distance of the ball does not decrease as much.

For this reason, when the distance of the ball needs to be delicately controlled, such as with a short iron, if the sweet spot is widened as in the case of a long iron, a problem arises in that it becomes difficult to control the flight distance.

In view of the above points, the present invention forms a frame part around the back design part of each iron head of each count, and also forms a recessed part with a constant wall thickness with the face surface in the center part, and the iron head of this recessed part By gradually increasing the area ratio to the entire part as you go from short irons to long irons, the weight is moved in the circumferential direction of the back design part to gradually widen the sweet spot as you go from short irons to long irons, Improves the probability of hitting the sweet spot due to differences in club length, stabilizes the ball flight direction and flight distance with long irons even when used by beginners, and improves the ball flight direction and flight distance with short irons. The purpose is to provide an iron club set that is easy to control.

Embodiments of the present invention will be described below based on the drawings.

1 to 6 show a first embodiment, in which a frame portion 4 is fixed to the back design portion 3 of the iron head 1 of each count, and a recess portion 5 recessed from the frame portion 4 is provided in the center portion. has been formed. The wall thickness of the recess 5 and the face surface 2 is the same for each iron number, and the area ratio of the recess 5 to the back design portion 3 gradually increases from the short iron 1c to the middle iron 1b and the long iron 1a. There is. Therefore, the weight of back design section 3 is
As you move from the short iron 1c to the long iron 1a, the weight gradually shifts toward the peripheral edge, but in this embodiment, the frame 4 is made of a different metal with a higher specific gravity than other parts to clarify the movement of the weight. . Further, in this embodiment, the thickness L between the frame portion 4 and the face surface 2 is gradually increased from the short iron 1c to the long iron 1a, thereby making the movement of the weight more clear.

The frame portion 4 has a second frame shown in FIGS. 7 to 12.
As in the embodiment, it may be integrated with other parts.

FIG. 13 is an explanatory diagram showing the rotation of the iron head 1 and the point of impact. That is, when the ball leaves the sweet spot P, the iron head 1 has a rotational speed V around the center of gravity G, and the iron head 1
causes rotation around the center of gravity G, and the ball flies out at a different angle to the target flight line direction, but due to the velocity V+ of the rotational speed V in the direction of the face, the ball that is in close contact with point A at the moment of impact Side spin N occurs due to gear action. Therefore, the trajectory of a ball launched at a different angle to the target flight line is corrected by the side spin N. From this, each iron head 1 of the first embodiment and the second embodiment has the same wall thickness T between the back design portion 3 and the face surface 2, and the center of gravity depth is the same.
Since PG is approximated, the side spin N that occurs when the ball misses the sweet spot P can be approximated by the set.

As mentioned above, the present invention forms a frame around the back design part of each iron head of each count, and also forms a recess in the center with a constant wall thickness relative to the face surface, and the area of this recess relative to the entire iron head. Since the ratio is gradually widened as you go from short irons to long irons, the weight moves in the circumferential direction of the back design part, and the sweet spot gradually becomes wider as you go from short irons to long irons, which increases the club length. This makes it possible to improve the probability of hitting the ball in the sweet spot due to the difference in iron length, and the direction and distance of the ball flight with long irons are stabilized, especially when used by beginners. It is possible to provide an iron club set that facilitates delicate control.

[Brief explanation of the drawing]

1 to 6 are rear views and A-A' cross-sectional views of an iron head according to a first embodiment of the present invention, and FIGS. 7 to 12 are views of an iron head according to a second embodiment of the present invention. Back and BB' sectional view, No. 13
The figure shows the rotation of the iron head and the movement of the striking point according to the present invention. 1...Iron head, 1a...Long iron, 1c...Short iron, 3...Back design portion, 4...Frame portion, 5...Concave portion, T...Thickness.

Claims (1)

[Claims for Utility Model Registration] 1. A frame portion 4 is formed around the back design portion 3 of the iron head 1 of each count, and a recess portion 5 having a constant thickness T with respect to the face surface 2 is formed in the center portion, This iron club set is characterized in that the area ratio of the recessed portion 5 to the entire back design portion 3 is gradually increased from the short iron 1c to the long iron 1a. 2. The iron club set according to claim 1, wherein the frame portion 4 is formed of a different metal having a higher specific gravity than the iron head 1 other than the frame portion 4. 3. Utility model registration claim 1 or 2, characterized in that the wall thickness L of the frame portion 4 and face surface 2 is gradually increased from the short iron 1c to the long iron 1a. iron club set.