JP2005168831A - Iron golf club head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the swing through performance of an iron golf club head without making the operability in sand shot difficult. <P>SOLUTION: The iron golf club head 1 has a face surface for hitting a ball, a back face surface 3 opposed to the face surface, and a sole surface 4 provided with a bounce angle connecting the face surface and the back face surface 3 at the lower part of the head. The sole surface 4 includes at least one groove-like recess 9 extended from the face surface side to the back face surface 3 side. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an iron type golf club head that can improve the swing-out performance of the head and is particularly suitable for an explosion shot in a bunker.

  A wedge-type iron-type golf club head used in rough and bunker is provided with a vance that is a bulge protruding downward on a sole surface constituting a bottom surface of the head. During a bunker shot, the bance collides with the sand and makes it easier for the head to bounce off the ground. As a result, the head is less likely to dive deep into the sand, and the sand under the ball can be thinly scraped off. Also, the ball on the bunker is launched with the momentum of the sand struck by the head. Such a shot is called an explosion shot in the sense of exploding sand.

  On the other hand, the vance on the sole surface is easy to come into contact with the ground surface, so that when the ball is to be hit cleanly from the lawn or the like, it causes a drop in the swinging performance of the head. When the head comes off badly, the head speed decreases and the flight distance is lost, or the face surface changes its direction and hits the ball in an unexpected direction.

  In order to solve the above-mentioned problems, for example, the sole surface of the head is provided with a protrusion called a runner that improves slippage of the sole (see Patent Document 1 below), and further, from the toe to the heel on the sole surface. The thing which provided the recessed part which extends long (refer the following patent document 2) etc. is proposed.

JP-A-5-192425 JP 7-299164 A

  In any of the heads of Patent Documents 1 and 2, the contact area of the sole surface is reduced during the swing, so that the swing-out performance of the head on the lawn is improved. However, in each of Patent Documents 1 and 2, since the bance effect on the sole surface is impaired, the operability at the time of an explosion shot with a bunker is deteriorated (making the explosion shot difficult). In particular, as in Patent Document 2, the groove extending in the toe and heel direction provided on the sole surface is substantially perpendicular to the moving direction of the sole during swinging. The resistance becomes large, and the missing of the head is remarkably deteriorated.

  The present invention has been devised in view of the above problems, and based on the basis that at least one groove-like recess extending from the face surface side to the back face surface side is included in the sole surface of the head. An object of the present invention is to provide an iron-type golf club head that can improve swing-out performance without making bunker shot operability difficult.

  According to the first aspect of the present invention, a face surface for hitting a ball, a back face surface that is the opposite surface, and a bounce angle that connects the face surface and the back face surface under the head are provided. An iron type golf club head having a sole surface, wherein the sole surface includes at least one groove-like recess extending from the face surface side to the back face surface side.

  According to a second aspect of the present invention, in the iron type golf club head according to the first aspect of the present invention, the groove-shaped recess is inclined toward the toe side from the face surface side toward the back face surface side.

  Further, in the invention according to claim 3, the groove-shaped recess includes a toe side groove wall portion extending from the groove bottom to the toe side, and a heel side groove wall portion extending from the groove bottom to the heel side. The angle θt of the groove wall portion on the toe side with respect to a straight line connecting the groove edges in the groove cross section at the groove width position is larger than the angle θh of the groove wall portion on the heel side with respect to the straight line. 2. An iron type golf club head according to 2.

  The invention according to claim 4 is characterized in that the groove-shaped recess includes at least two grooves provided at a distance of 2 to 10 mm in the toe and heel directions. It is an iron type golf club head of description.

  Further, the groove-like recess has the largest groove width at a substantially central portion between the end on the face surface side and the end on the back face surface side, and the both ends 5. The iron type golf club head according to claim 1, wherein the groove width gradually decreases toward the portion.

  According to a sixth aspect of the present invention, the groove-shaped recess has a heel side groove edge located on the heel side and a toe side groove edge located on the toe side, and at least the heel side groove edge. 6. The iron-type golf club head according to claim 1, wherein the iron-type golf club head has an arcuate curve that protrudes toward the heel side.

  The iron type golf club head of the present invention includes at least one groove-like recess extending from the face surface side to the back face surface side on the sole surface. Since such a groove-shaped recess extends in a direction along the moving direction of the sole surface, the groove-shaped recess does not get caught even when contacting the ground. In addition, since the concave groove portion can be provided with a portion having a low contact pressure with respect to the ground surface on the sole surface, the head can be easily removed even during a bunker shot or duff. Further, the groove-like recess of the present invention can be easily shortened in length as compared with the groove extending in the toe and heel directions. Therefore, it is possible to prevent the contact area of the sole surface with the ground from being significantly reduced. For this reason, the buns provided on the sole surface are sufficiently functioned, and the operability of the bunker shot including the explosion shot is not deteriorated.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a plan view of an iron type golf club head (hereinafter, simply referred to as “head”) 1 according to the present embodiment, FIG. 2 is a side view of the iron type golf club head 1 as viewed from the toe side, and FIG. 4 and 4 are perspective views of the head as seen from the back face surface side. The head 1 includes a head body 1a and a hosel portion 1b into which a shaft (not shown) is inserted. In this embodiment, an example in which all is made of a metal material is exemplified, but a fiber reinforced resin or the like may be used in part.

  The head main body 1a includes a face surface 2 on which a ball is hit, a back face surface 3 which is the opposite surface, and a sole provided with a bounce angle θ connecting the face surface 2 and the back face surface 3 below the head. The surface 4 is divided by a top blade surface 5 that connects the face surface 2 and the back face surface 3 above the head, and a toe surface 6 that connects the face surface 2 and the back face surface 3 on the head tip side. The head main body 1a is continuous with the hosel portion 1b through the heel 7. The hosel part 1b is provided with a cylindrical shaft insertion hole 10 into which a shaft (not shown) is inserted. The axial center line CL of the shaft insertion hole 10 substantially coincides with the axial center line of the shaft to be inserted later.

  1 to 3 all show the reference state of the head 1. The reference state uniquely defines the posture of the head 1 with respect to the horizontal plane HP. Specifically, the axial center line CL of the shaft insertion hole 10 is arranged in an arbitrary vertical plane VP1, and is tilted at a lie angle determined for the head. Further, the face surface 2 is inclined at a loft angle α (real loft angle) determined for the head, and the sole surface 4 is in contact with the horizontal plane HP.

  The head 1 of this embodiment is suitable for a shot from a bunker. Therefore, for example, what is called a wedge including a so-called sand wedge or approach wedge having a real loft angle of 45 degrees or more, more preferably 48 degrees or more is suitable. The figure illustrates a sand wedge head 1, but the invention is not limited to such a count.

  The sole surface 4 of the head 1 is provided with a bounce angle as described above. The bounce angle θ is such that a straight line N connecting a leading edge LE that is the front end of the sole surface 4 (or the tip portion of the head that protrudes most forward) and a trading edge TE that is the rear end of the sole surface 4 is the horizontal plane. It is an angle formed with HP. The leading edge LE is at a higher position than the trading edge TE. If the bounce angle is too large, the swing-out property deteriorates, and if it is too small, the bunker shot becomes difficult. For example, 6 to 14 degrees is desirable. Further, the maximum width W of the sole surface 4 can be determined according to a custom, and for example, about 15 to 25 mm can be adopted.

  Further, as shown in FIG. 4, the sole surface 4 has a sole base surface 8 that extends smoothly from the toe to the heel with a curved surface that protrudes smoothly toward the outer surface of the head, and at least one that is recessed from the sole base surface 8. This includes a plurality of groove recesses 9 (preferably four in this example). The sole base surface 8 is a curved surface forming the bounce, and can be formed in substantially the same shape as a conventional customary head shape.

  As shown in FIGS. 3 and 4, the groove-shaped recess 9 has an end 10 on the face surface side and an end 11 on the back face surface side, from the face surface 2 side to the back face surface 3 side ( Or it extends from the back face surface 3 side to the face surface 2 side). That is, the longitudinal direction is not the toe-heel direction but the face surface 2 -back face surface 3 direction. The groove-shaped recess 9 is a concept including not only a groove that can completely distinguish the groove wall, the groove bottom, and the like, but also a recess that is not clear.

  The groove-like recess 9 of the present invention has a shorter length than the groove extending in the toe and heel directions. Accordingly, it is possible to prevent the contact area of the sole surface 4 with the ground from being significantly reduced. For this reason, it is possible to leave a vance provided on the sole surface 4, in particular, a vance continuous from the leading edge LE to the trading edge TE. Therefore, since the bounce can be used effectively, the bunker shot including the explosion shot can be easily performed, and the operability is not deteriorated.

  Further, the groove-like recess 9 extends in a direction substantially the same as or very close to the moving direction of the sole surface 4 at the time of swing. For this reason, the groove-shaped recess 9 does not become a resistance even when the sole surface 4 and the ground are in contact with each other, but rather the groove edge of the groove-shaped recess 9 can function as a guide (guide body) when the sole surface 4 swings. Thereby, even when the sole surface 4 comes into contact with the ground during the swing, the orientation of the face surface 2 is unlikely to change, which helps to stabilize the directionality of the hit ball. Moreover, the groove-shaped recessed part 9 takes in lawn or sand in the recessed part, and forms the location where the contact pressure with respect to the ground is low. Thereby, the omission of the head 1 can be improved.

  Particularly preferably, as shown in FIG. 3, a groove-like recess 9 extending from the face surface 2 side toward the back face surface 3 side toward the toe side is desirable. When performing a bunker shot, as shown in FIG. 5, many golfers hold the face surface 2 open with respect to the target direction and swing from the outside to the inside (so-called outside-in-orbit swing). By doing so, the effect of Vance is enhanced. When the groove-shaped recess 9 is inclined as described above, the moving direction of the sole surface 4 during swing and the longitudinal direction of the groove-shaped recess 9 are closer to each other, so that the contact resistance between the sole surface 4 and the ground is further reduced. In addition, the swinging performance of the head can be further improved.

  From the above viewpoint, as shown in FIG. 3, the straight line connecting the end portion 10 on the face surface side and the end portion 11 on the back face surface side of the groove-shaped recess 9 in the bottom view of the head 1 in the reference state is described above. An angle γ formed by the straight line K projected on the horizontal plane HP and the second vertical plane VP2 orthogonal to the vertical plane VP1 is 10 degrees or more, more preferably 20 degrees or more. In combination with the heel, 40 degrees or less, more preferably 30 degrees or less is desirable. In addition, when the edge part of the groove-shaped recessed part 9 has a width | variety, let the intermediate position be an edge part.

  Further, the groove-shaped recess 9 of the present embodiment has the largest groove width GW at the substantially central portion in the longitudinal direction, and the groove width gradually decreases from the groove toward the both end portions 10 and 11. ing. This helps to ensure a large area occupied by the sole base surface 8 (bounce) at the face surface side and the back face side of the sole surface 4 while ensuring a sufficient groove volume in the groove-shaped recess 9. In particular, since the face surface 2 side of the sole surface 4 is a portion that first collides with the sand surface in the explosion shot, the sand can be made more effective by securing more sole base surfaces 8 that form bounces in such portions. Can explode and hit an explosion shot easily.

  In addition, if the groove width GW is too small, the groove-shaped recess 9 tends to reduce the effect of improving the head slippage. . Although there is no restriction | limiting in particular from such a viewpoint, the maximum groove width GW is 5 mm or more, for example, More preferably, 9 mm or more is desirable, and about the same upper limit, 15 mm or less, More preferably, 12 mm or less is desirable. Further, the depth of the groove-like recess 9 is not particularly limited, but if it is too small, it is difficult to obtain the effect of reducing the contact pressure. Conversely, if the depth is too deep, the center of gravity of the head tends to increase. From such a viewpoint, the depth of the groove-like recess 9 is preferably 0.5 mm or more, more preferably 1.0 mm or more, and the upper limit is preferably 2 mm or less, more preferably 1.5 mm or less. . Furthermore, the length of the groove-like recess 9 is desirably about 0.8 to 1.2 times the sole width W.

  FIG. 6 shows a partial end view taken along line AA of FIG. 3, and FIG. 7 further shows a partially enlarged view. These cross-sectional views show a cross section perpendicular to the longitudinal direction of the groove-like recess 9, and FIG. 7 shows a cross section at the position of the maximum groove width GW. The groove-like recess 9 includes a toe side groove wall portion 9a extending from the groove bottom 9c having the largest dent amount to the toe side, and a heel side groove wall portion 9b extending from the groove bottom 9c to the heel side, In this example, the groove wall sections 9a and 9b are planar, and the groove section is exemplified by a substantially triangular shape.

  Further, as shown in FIG. 7, the groove-shaped recess 9 includes a toe side groove edge 13 located on the toe side and a heel side groove edge located on the heel side in the groove cross section at the position of the maximum groove width GW. The angle θt of the toe side groove wall portion 9a with respect to the straight line HL connecting to 12 is set larger than the angle θh of the heel side groove wall portion 9b with respect to the straight line HL.

  The concave groove 9 of the present embodiment is inclined to the toe side from the face surface 2 side toward the back face surface 3 side. If the swing is performed with the face surface 2 of the head 1 held in a square instead of being open, the groove wall portion 9b on the heel side of the concave groove portion 9 may become a resistance when it collides with the ground. In the present embodiment, the groove wall portion 9b on the heel side of the concave groove portion 9 is set to a small angle θh with respect to the straight line HL, so that the groove on the heel side even when the swing is performed in a square (inside-in track). The wall portion 9b is less likely to get caught on the ground, and the head can be easily pulled out. Specifically, the angle θh is preferably 10 degrees or more, more preferably 15 degrees or more, and the upper limit is 40 degrees or less, more preferably 30 degrees or less.

  On the other hand, the groove wall 9b on the heel side is effective to increase the angle θt with respect to the straight line HL in order to ensure a sufficient bounce effect. From such a viewpoint, the angle θt of the toe side groove wall portion 9a is preferably 60 degrees or more, more preferably 75 degrees or more. If the angle θt exceeds 90 degrees, the groove wall portion becomes a so-called undercut, which makes processing difficult. Therefore, the upper limit is desirably 90 degrees.

  Moreover, as FIG. 8 shows, the groove-shaped recessed part 9 may form groove | channel wall surface 9a, 9b and the groove bottom 9c in a curved surface. In this case, the angle of the groove bottom can be obtained from the tangent line L1 or L2 of the inflection points P1 and P2 and the straight line HL. Further, the cross-sectional shape of the groove-shaped recess 9 is not limited to these exemplary forms, and it is needless to say that various forms such as a square groove shape and a semicircular shape can be adopted.

  Further, the groove-like recess 9 of the present embodiment is configured by an arcuate curve in which the groove edge 12 on the heel side is convex toward the heel side in the bottom view of FIG. The arcuate curve includes a composite arc, and a combination of an arc and a straight line, in addition to an aspect formed by a single arc. In the case of a single unit, for example, the radius of curvature is preferably about 10 to 20 mm. Even when such a groove edge 12 is displaced between the swing path of the head 1 and the longitudinal direction of the groove-shaped recess 9, the groove edge 12 is less likely to be caught on the ground. Therefore, it is possible to suppress the change in the orientation of the face. In this example, the toe side groove edge 13 is formed by a substantially straight line, but it can also be formed by a curved line. Particularly preferably, it is desirable that the groove edges 12 and 13 are smoothly chamfered and connected to the sole base surface 8 as shown in FIG.

  In the case where a plurality of groove-like recesses 9 are provided, it is preferable that at least two, more preferably 2 to 4 provided at a distance Y in the toe and heel directions are included. Here, the distance Y is preferably 2 mm or more, more preferably 3 mm or more, and the upper limit is preferably 10 mm or less, more preferably 7 mm or less. Thereby, it is possible to easily secure a bounce between the groove-like recesses 9 and 9 in the swing direction (from the face surface 2 to the back face surface 3 direction).

  The groove-shaped recess 9 as described above can be formed by forging, casting, or machining. In the present embodiment, the groove extends substantially linearly. Needless to say, the present invention may include a curved or zigzag groove-like recess 9.

  Performance tests were performed on sand wedges (SW) based on the specifications in Table 1. Each head has a common specification with a lie angle of 63.5 degrees, a real loft angle of 58 degrees, a bounce angle of 8 degrees, and a sole width of 20 mm at the center of the face (middle point of the score line). Only the shape is different. The cross-sectional shape of the groove-shaped recess is shown in FIG. .

  In the performance test, 10 golfers with handicap 10-18, from the rough and the bunker to the golf ball (“SIO Sports” “XXIO”) towards the target of 20 yards, 30 yards and 40 yards ahead Each ball was hit by 10 balls, and the goodness of the head and the variation in flight distance were evaluated by the sensuality of each golfer. A result is an average value of 10 people, and shows that it is so favorable that a numerical value is large. Table 1 shows the test results.

  As a result of the test, it can be seen that the heads of the examples have good omissions, and that there is little variation in the flight distance especially on bunker shots. It is considered that the head of the example led to good swing-out and flight distance control performance on a bunker shot by the synergistic action of the bounce and the groove-shaped recess. These examples confirmed the effects of the present invention.

It is a top view of the head of the reference state which shows the embodiment of the present invention. It is the side view which looked at it from the toe side. It is a bottom view of FIG. It is the perspective view seen from the back face side of the head. 6 is a schematic plan view illustrating a swing of a bunker shot. It is AA sectional drawing of FIG. FIG. 6 is a partially enlarged view. It is sectional drawing of the groove-shaped recessed part which shows other embodiment. FIG. 6 is a bottom view of the head of Comparative Example 1 and its X-X ′ sectional view. FIG. 10 is a bottom view of a head of Comparative Example 2 and a cross-sectional view along X-X ′ thereof. FIG. 10 is a bottom view of the head of Comparative Example 3 and a cross-sectional view along X-X ′ thereof. It is groove sectional drawing of the groove-shaped recessed part of an Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Iron type golf club head 2 Face surface 3 Back face surface 4 Sole surface 9 Groove-shaped recessed part 9a Groove wall part 9b on the toe side of groove-shaped recessed part 10 Groove wall part on the heel side of groove-shaped recessed part 10 Face side of groove-shaped recessed part End 11 of the groove-shaped recess on the back face surface side groove edge 13 on the heel side of the groove-shaped recess 13 groove edge on the toe side of the groove-shaped recess

Claims (6)

An iron type golf club head having a face surface for hitting a ball, a back face surface which is the opposite surface, and a sole surface provided with a bounce angle connecting the face surface and the back face surface under the head. ,
The iron type golf club head according to claim 1, wherein the sole surface includes at least one groove-like recess extending from the face surface side to the back face surface side.   2. The iron-type golf club head according to claim 1, wherein the groove-shaped recess is inclined toward the toe side from the face surface side toward the back face surface side. The groove-shaped recess includes a toe side groove wall portion extending from the groove bottom to the toe side, and a heel side groove wall portion extending from the groove bottom to the heel side,
In the groove cross section at the maximum groove width position, an angle θt of the toe side groove wall portion with respect to a straight line connecting the groove edges is larger than an angle θh of the heel side groove wall portion with respect to the straight line. Item 3. The iron-type golf club head according to Item 1 or 2.   4. The iron-type golf club head according to claim 1, wherein the groove-shaped recess includes at least two grooves provided at a distance of 2 to 10 mm in the toe and heel directions. The groove-like recess has the largest groove width at a substantially central portion between the end on the face surface side and the end on the back face surface side,
5. The iron type golf club head according to claim 1, wherein the groove width gradually decreases toward the both end portions. The groove-shaped recess has a heel side groove edge located on the heel side and a toe side groove edge located on the toe side,
6. The iron type golf club head according to claim 1, wherein at least a groove edge on the heel side is formed of an arcuate curve that is convex toward the heel side.

Images