JP5908019B2 - Golf club head - Google Patents

Description

  The present invention relates to an iron-type golf club head manufactured by forging.

  A golf club head having a low center of gravity has an effect that a hit ball is more likely to rise than a golf club head that does not. For this reason, golf club heads having a low center of gravity are preferred and used by average golfers.

  In order to lower the center of gravity of the golf club head, the total weight of the golf club head is basically not changed, but the weight of the top portion of the upper portion of the golf club head is reduced and the weight of the lower sole portion is increased. There is a need. For this reason, when the center of gravity of the golf club head is lowered, the top portion side of the golf club head becomes thin. In recent years, the center of gravity of a golf club head has been lowered, and accordingly, the thickness of the top portion of the head has been reduced.

  By the way, the golf club head is a cavity back type golf club head in which a concave portion is provided on the back surface of the rear portion of the golf club head, and is further formed by expanding the concave portion from the concave portion toward the sole in an undercut shape. An undercut type golf club head is known. This undercut type golf club head can distribute the weight of the golf club head reduced by the formation of the concave portion of the back surface or the concave portion of the undercut shape to the sole portion side. For this reason, it becomes easy to design a golf club head having a low center of gravity by adopting the undercut type.

  When this undercut type golf club head is manufactured by forging, the face part constituting the hitting surface of the front part of the golf club head and the head main body part constituting the part excluding the face part are separated in advance. In general, a method in which these are manufactured and joined by welding (see, for example, Patent Document 1).

  However, the golf club head manufactured by the method of joining the face portion and the head main body portion has a thin top portion of the head main body portion corresponding to the plate thickness of the face portion. There was a problem that the top part of the main body part was distorted and deformed.

  Further, the center of gravity of the head of the cavity back type golf club head manufactured by forging the face portion and the head main body portion integrally from the beginning without lowering the face portion and the head main body portion is lowered. For this reason, when the top portion is formed thin, the top portion may be deformed by repeated hitting of the ball.

  This problem can be solved by manufacturing a golf club head using a high-strength material such as SUS630 without using a general low-carbon steel such as S20C. However, a high-strength material is expensive, and when a golf club head is manufactured using a high-hardness material, a new problem arises that the angle cannot be adjusted. For this reason, use of a high-strength material is not preferable.

JP 2006-223686 A

  Therefore, the present invention is an iron-type golf club head manufactured by forging using carbon steel and having a concave portion at the rear portion, and the top portion of the golf club head is not deformed even if the ball is repeatedly hit. The purpose is to provide.

The golf club head according to claim 1 of the present invention has a plate-like face portion having a plurality of score lines and constituting a ball striking face, and is located behind the face portion and is connected to the upper end portion of the face portion at the upper part. An iron-type golf club head comprising a head main body portion having a top portion, a rear portion having a concave portion having the face portion as a bottom surface, and at least the head main body portion being made of a steel material having a carbon content of 0.5% by mass or less. A point that includes a line connecting the centers of the plurality of score lines and intersects the surface perpendicular to the ball striking surface and the upper end of the top portion as a reference point, includes the reference point, and includes the ball striking surface. When the plane perpendicular to the tangent to the upper end of the top portion in the direction parallel to the reference plane is taken as the reference plane, and the range within 10 mm on both sides in the direction perpendicular to the reference plane is taken as the reference range, this reference range Oite, the average cross-sectional area of a cross section in a direction parallel to said reference surface of said top portion at the rear from the extension plane of the bottom surface of the recess is not more 24 mm ² or less, from the rear surface of the top portion of the cross An arbitrary five-point Vickers hardness within a range of 1 mm or less is 240 or more.

  A golf club head according to a second aspect of the present invention is the golf club head according to the first aspect, comprising a substantially cylindrical hosel hole for inserting the shaft, wherein the bottom surface of the hosel hole where the tip of the shaft is located is provided. As a reference, the Vickers hardness is 200 or less in a range within 5 mm on both sides in a direction parallel to the central axis of the hosel hole.

  According to the golf club head of the present invention, since the hardness is high even if the top portion is thin, the top portion is not deformed even if the ball is repeatedly hit.

  Further, according to the golf club head of the present invention, the hardness in the vicinity of the hosel hole is not high, so that the angle can be adjusted without any problem.

1 is a plan view when a back portion is viewed from a direction perpendicular to a face surface of a golf club head of Example 1. FIG. It is a top view when a face part is seen from the direction perpendicular | vertical to a face surface same as the above. It is a partially expanded sectional view in the reference plane E of FIG. It is sectional drawing of a hosel part same as the above.

  Hereinafter, embodiments of the golf club head of the present invention will be described with reference to the accompanying drawings.

  1 to 4 showing the golf club head of the present embodiment, reference numeral 1 denotes an iron-type golf club head (hereinafter referred to as “head”), and a plate-like face portion 2 and a rear portion of the face portion 2. The head main body 3 is located. The face portion 2 and the head main body portion 3 are separately formed by forging and joined by welding. The face portion 2 and the head main body portion 3 are made of a steel material having a carbon content of 0.3% by mass or less, such as S20C, S25C, or a steel material having a carbon content of 0.5% by mass or less, such as S45C.

  The material for forming the face portion 2 is not limited to the above, and a high-strength material can be used. Examples of the high-strength material include special steel having a carbon content of about 0.5% by mass.

  The face part 2 has a plurality of score lines 4 and constitutes a hitting surface 5 for hitting a ball.

  The head main body 3 has a top 6 connected to the upper end of the face 2 at the top, a sole 7 at the bottom, and a back 8 at the rear. The head 1 has a hosel portion 9 connected to the shaft on one side. An opening 10 is formed in the head main body 3, and the opening 10 is closed by the face 2, whereby a recess 11 having the face 2 as the bottom surface 11 a is formed in the back 8 of the head 1. Is formed. The recess 11 is also called a cavity because it has a cavity shape. The hosel portion 9 is formed with a substantially cylindrical hosel hole 12 into which a shaft is inserted.

  The head 1 may be formed by integrally forging the face portion 2 and the head main body portion 3 from the beginning without forming the face portion 2 and the head main body portion 3 separately. In this case, the boundary between the face portion 2 and the head main body portion 3 is an extended surface of the bottom surface 11 a of the recess 11 corresponding to the back surface of the face portion 2. That is, as in the case where the face portion 2 and the head main body portion 3 are formed separately, even when the face portion 2 and the head main body portion 3 are integrally formed, as shown in FIG. Has a top portion 6 separated from the upper end of the face 2.

  And in the predetermined range of the top part 6 of the head main-body part 3, a cross-sectional area and hardness are set as follows.

A point C including a line A connecting the centers of the plurality of score lines 4 and perpendicular to the hitting surface 5 and the upper end of the top portion 6 is defined as a reference point. A plane E that includes the reference point C and is orthogonal to the tangent line D at the upper end of the top portion 6 in the direction parallel to the ball striking face 5 is taken as a reference plane. A range F within 10 mm on both sides in the direction perpendicular to the reference plane E is set as a reference range. At this time, in the reference range F, the average cross-sectional area of the cross section S in the direction parallel to the reference surface E of the top portion 6 is 24 mm ² or less, and the range is within 1 mm from the rear surface 13 of the top portion 6 of the cross section S. An arbitrary five-point average Vickers hardness at K is 240 or more. More preferably, an arbitrary five-point Vickers hardness not limited to the range K of the cross section S is 300 or more. Thereby, when the average cross-sectional area of the top portion 6 in the reference range F is as small as 24 mm ² or less, the top portion is not deformed even if the ball is repeatedly hit.

  Further, the hardness is set as follows in a predetermined range of the hosel part of the head main body part 3.

  The Vickers hardness is 200 or less in a range J within 5 mm on both sides in the direction parallel to the central axis H of the hosel hole 12 with reference to the bottom surface G of the hosel hole 12 where the tip of the shaft is located. Thereby, the angle adjustment performed by bending the range J of the hosel portion 9 can be performed without any problem. In addition, when S20C is used for the material, the Vickers hardness of the head main body 3 made by forging is 150 to 180. Further, when S30C is used as the material, the Vickers hardness of the head main body portion 3 created by forging is 160 to 190, and when S45C is used as the material, the Vickers hardness of the head main body portion 3 created by forging is about 200. It is.

  Hereinafter, a method for manufacturing the golf club head of this embodiment will be described.

  First, using a steel material with a carbon content of 0.3 mass% or less, such as S20C, S25C, or a steel material with a carbon content of 0.5 mass% or less, such as S45C, forging the prototype of the head main body 3. To form. And using a high frequency heater, only the top part 6 is partially heated and quenched. Optimum quenching conditions vary depending on the material, but when S20C is used, for example, the heating temperature may be 950 to 1050 ° C. and the heating time may be 10 to 30 seconds. The quenching conditions are set so as to have a predetermined hardness in a predetermined range of the top portion 6 of the head main body 3 as described above.

  Thereafter, the separately formed face part 2 is joined to the head main body part 3 by welding or the like, and the head 1 is obtained through other predetermined processes such as grinding, polishing and finishing.

  Hereinafter, the result of actually creating and evaluating the head 1 will be described.

  Using S20C as a material, the prototype of the head main body 3 was formed by forging.

  And using the output 15kW high frequency heater, only the top part 6 was partially heated and quenched. The quenching conditions were such that the heating temperature was 982 to 1038 ° C., the heating time was 15 seconds, and after the heating was finished, the air was cooled to 25 to 32 ° C. over 20 seconds using an air jet cooler. Then, the separately formed face part 2 was joined to the head main body part 3 by welding or the like, and the head 1 was obtained through predetermined processes such as grinding, polishing, and finishing.

In the reference head F, the finished product of the head 1 had an average sectional area of a section S in a direction parallel to the reference surface E of the top portion 6 of 24 mm ² or less. In the reference range F, the Vickers hardness at any five points in the cross section S was 202 to 315, and the five-point average Vickers hardness was 300 or more. In addition, an arbitrary five-point average Vickers hardness in a range K within 1 mm from the rear surface 13 of the top portion 6 of the cross section S was 240 or more.

  Next, a durability test was performed using the prepared head 1. A ball having a speed of 42 m / sec was repeatedly applied to the center of the hitting surface 5 with 2000 shots, 500 shots on the heel side near the hosel portion 9, and 500 shots on the toe side far from the hosel portion 9. As a result, the top portion 6 was not deformed.

  As Comparative Example 1, the head 1 was prepared under the same conditions as described above except that the top part 6 was not quenched, and the durability test was performed under the same conditions as above. As a result, the top part 6 was deformed.

As Comparative Example 2, the top portion 6 is not quenched, and the average cross-sectional area of the cross section S in the direction parallel to the reference plane E of the top portion 6 is 24 in the reference range F of the finished product of the head 1. The head 1 was prepared under the same conditions as described above except that the thickness was 0.9 mm ^2. A ball having a speed of 42 m / sec was repeatedly applied to the center of the hitting surface 5 with 2000 shots, 500 shots on the heel side, and 500 shots on the toe side. As a result, the top portion 6 was not deformed.

From these results, in the reference range F, when the average cross-sectional area of the cross section S in the direction parallel to the reference plane E of the top portion 6 is 24 mm ² or less, in the reference range F, the top portion 6 of the cross section S It was confirmed that the arbitrary five-point average Vickers hardness in the range K within 1 mm from the rear surface 13 is 240 or more, so that the top portion 6 is not deformed even when the ball is repeatedly hit.

As described above, the golf club head 1 according to the present embodiment includes the plate-like face portion 2 having a plurality of score lines 4 and constituting the hitting surface 5, and the face located above and in the rear of the face portion 2. A head main body portion 3 having a top portion 6 continuous with an upper end portion of the portion 2, and has a concave portion 11 with the face portion 2 as a bottom surface 11a at a rear portion, and at least the head main body portion 3 has a carbon content of 0.5. An iron-type golf club head 1 made of a steel material of less than mass%, and includes a surface B that includes a line A connecting the centers of the plurality of score lines 4 and is perpendicular to the hitting surface 5, and the top portion 6. A point C where the upper end intersects is used as a reference point, and a plane E including the reference point C and perpendicular to the tangent line D of the upper end of the top portion 6 in a direction parallel to the hitting surface 5 is used as a reference surface. Both sides 1 in the direction perpendicular to plane E When the range F within 0 mm is set as a reference range, in this reference range F, an average cross-sectional area of a cross section S in a direction parallel to the reference surface E of the top portion 6 is 24 mm ² or less, Since the average Vickers hardness of any five points in the range K within 1 mm from the rear surface 13 of the top portion 6 of the cross section S is 240 or more, even if the top portion 6 is thin, the hardness is high. The top part 6 is not deformed.

  Further, a substantially cylindrical hosel hole 12 for inserting the shaft is provided, and a direction parallel to the central axis H of the hosel hole 12 with respect to the bottom surface G of the hosel hole 12 where the tip of the shaft is located In the range J within 5 mm on both sides, since the Vickers hardness is 200 or less, the hardness in the vicinity of the hosel hole 12 is not high, and the angle can be adjusted without any problem.

  In addition, this invention is not limited to said embodiment, A various deformation | transformation implementation is possible.

DESCRIPTION OF SYMBOLS 1 Golf club head 2 Face part 3 Head main-body part 4 Score line 5 Hitting surface 6 Top part
11 Recess
12 Hosel hole
13 Rear surface A Line B Surface C Reference point D Tangent E Reference surface F Reference range G Bottom surface H Center axis J Range K Range

Claims (2)

A plate-like face portion having a plurality of score lines and constituting a hitting surface, and a head main body portion having a top portion connected to the upper end portion of the face portion at the rear of the face portion, and at the rear portion. An iron-type golf club head having a concave portion with the face portion as a bottom surface and at least the head main body portion made of a steel material having a carbon content of 0.5% by mass or less, connecting the centers of the plurality of score lines. A reference point is a point where a plane that includes a line and is perpendicular to the hitting surface and the upper end of the top portion, and includes the reference point and the upper end of the top portion in a direction parallel to the hitting surface. a plane perpendicular to the tangent to the reference plane, when the reference range of a range within a vertical direction on both sides 10mm with respect to the reference plane, in this reference range, the rear from the extension plane of the bottom surface of the recess Definitive the average cross-sectional area in a direction of a cross section parallel to the reference surface of the top portion is not more 24 mm ² or less, any average five points Vickers hardness in the range of plane within 1mm after the top portion of the cross section Is a golf club head characterized by being 240 or more. In the range within 5 mm on both sides in the direction parallel to the central axis of the hosel hole, with reference to the bottom surface of the hosel hole where the tip of the shaft is located, with a substantially cylindrical hosel hole for inserting the shaft The golf club head according to claim 1, wherein the Vickers hardness is 200 or less.