JP2010131140A - Iron golf club and method of manufacturing the same - Google Patents

Abstract

A golf club capable of sharpening a corner portion of a score line edge portion within a new standard.
In an iron golf club, in a cross section cut by a plane perpendicular to the longitudinal direction of a face surface and a groove, a radius at which a contour line of an edge of the groove is in contact with the face surface and the side surface of the groove is 0.010. So that there is a first circle a in inches (0.254 millimeters) and a second circle b having the same center radius as the first circle 0.011 inches (0.2794 millimeters). did. At the edge of the groove, a projecting convex portion 18 is provided adjacent to the face surface in line with the contour line. The groove shape was mechanically processed with the tool 20 so as to have an accurate dimension.
[Selection] Figure 4

Description

  The present invention relates to an iron golf club having a score line on a face and a method for manufacturing the same.

  A plurality of grooves called score lines are provided on the face of the golf club head. This score line affects the performance of applying a spin to the ball at the time of hitting to stabilize the spin rate, so-called spin performance. In particular, in the case of an iron, an iron having a small loft angle (for example, 20 degrees to 30 degrees) is referred to as a long iron, and an iron having a large loft angle (for example, 40 degrees to 60 degrees) is referred to as a short iron. Usually, numbers and symbols such as 1, 2, 3,..., 9, PW (pitching wedge), SW (sand wedge) are given from the long iron to the short iron.

  Among them, short irons such as PW (pitching wedge) and AW (approach wedge) and SW (sand wedge) with loft angles of 45 to 60 degrees have a spin performance from professional players and advanced players. High ones are preferred. This is because as the loft angle increases, the flight distance of the ball decreases, and in the scene where the iron with a large loft angle is used, the area that the player aims as the goal of the ball also narrows, but in this case, hitting without making an extra run This is because it is advantageous to stop the ball near the landing point of the ball. Also, in professional games, the green is hard and the ball is set to roll quickly on it, so it is necessary to spin the ball and stop it near the landing point.

  Among long irons and middle irons, those having high spin performance are desirable because a stable spin amount leads to a stable flight distance. In particular, in a shot from a rough, there is a possibility that a flyer phenomenon occurs in which a spin is not applied and the player flies more than the intended flight distance. Therefore, stable spin performance is required for shots in various situations.

  Various methods have been proposed and known for the production of this score line. For example, after the score line is provided on the face surface by pressing, the face surface is uniformly cut and flattened by plane milling. Thus, a manufacturing method in which the edge portion of the score line is provided on the face surface has been proposed (see Patent Document 1). In addition, a method of manufacturing a high-quality golf club head that is excellent in manufacturing efficiency by forging with a projection formed in a trapezoidal shape in which the shape of the groove of the score line is deformed (Patent Document 2). reference).

  In the Japan Golf Association, the score line groove must have a circular shape with a radius of 0.020 inches (0.508 millimeters) or less, and the width is 30 degrees (R & A) The distance between adjacent grooves should be at least three times the width of the groove and 0.075 inches (1.905). The depth must be 0.020 inches (0.508 millimeters) or less.

From January 1, 2010, in an iron golf club with a loft angle of 25 degrees or more, the roundness of the edge is the same as this circle, with the radius of the circle in contact with the face being 0.010 inches (0.254 mm) The convention is changed to fit within a central circle 0.011 inch (0.2794 millimeters).
JP 2003-199851 A JP 2003-93560 A

  However, there are concerns that the new rules will reduce spin performance from professional players and advanced players. Therefore, there is a demand for an iron golf club that does not lose spin performance within a range that meets the regulations. As described above, the spin performance depends on the shape of the score line. The shape of the edge of the score line also affects the performance of applying a spin. This shape also depends on the machining method. In the new standard, there are further restrictions on the shape, so a further solution is required.

  The present invention has been made based on the technical background as described above, and achieves the following object. The object of the present invention is to solve the above problems, and even in the score line according to the new standard, the spin amount can be stabilized and the spin performance can be improved by forming a minute convex part at the edge part of the score line, An object of the present invention is to provide an iron golf club and a manufacturing method thereof. Another object of the present invention is to provide an iron golf club and a method for manufacturing the same that can form a score line having a stable and reliable shape.

In order to achieve the above object, the present invention employs the following means.
The iron golf club of the present invention 1
A head body having a face (3) formed with several grooves (10, 15) having a toe heel direction as a longitudinal direction on the front surface, and a shaft mounting portion provided on one side, and connected to the shaft mounting portion In an iron golf club with a shaft,
In the cross section cut by the face perpendicular to the longitudinal direction of the face (14) and the groove (15) of the face (3), the outline (19) of the edge of the groove (15) is the face surface (14). ) And a first circle (a) having a radius of 0.010 inch (0.254 mm) in contact with the side surface of the groove (15);
This first circle (a) and the same center radius between the second circle (b) of 0.011 inch (0.2794 millimeters),
Protruding protrusions (18) are formed in the vicinity of the edge of the groove (15).

The iron golf club of the present invention 2 is characterized in that, in the present invention 1, the convex portion (18) is formed adjacent to the face surface (14).
In the iron golf club of the present invention 3, in the present invention 1, the convex portion (18) is an angle formed of one or more formed by intersecting two straight lines, and the angle B is 90 degrees ≦ B ≦ 120 degrees. It is characterized by that.

  A method for manufacturing an iron golf club according to a fourth aspect of the present invention is the method for manufacturing an iron golf club according to the first to third aspects of the present invention. It is characterized by forming by grinding by machining or grinding by a grinding tool (20).

  As described above, according to the iron golf club and the manufacturing method thereof of the present invention, the score line edge portion is provided with a convex portion, and the end portion having the angle of the convex portion is sharpened within a specified range. Therefore, even in the new regulations, the ball is easily caught when hit, and the spin effect can be enhanced by stabilizing the spin amount compared to those having no convex portions even in various situations. Further, by mechanically processing the convex portion and the contour line portion connected to the convex portion, the convex portion and the like can be surely formed into an accurate and stable shape.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the attached drawings, taking an iron type golf club head as an example. First, the structure of the iron golf club that is the base of the present embodiment is as follows. As shown in FIGS. 1 to 3, a golf club is formed by the head 1 and the shaft 2. The head 1 is made of a metal material such as low-carbon steel such as S20C, stainless steel, titanium-based alloy, etc. The face 3 is a hitting surface on the front surface, the sole 4 is on the lower side, and the heel 5 is provided on one side. A shaft mounting portion 6 for connecting the shaft 2 is formed on the heel 5, a top 7 is formed on the top, and a toe 8 is formed on the other side. Further, a cavity 9 is formed on the back surface of the head 1 so as to substantially face the face 3. Moreover, the muscle back shape without a recessed part may be sufficient.

  A plurality of score lines 10 that are linear grooves are formed in the face 3 in the lateral direction. The cross-sectional shape of the score line 10 is a V shape, a U shape, a trapezoid, or the like. This cross section is a groove formed as a recess on the surface of the face 3 by pressing, cutting, or the like using a metal mold called a linear mold. Further, a count display 11 is formed on the sole 4. The count display 11 is formed as a recess on the surface of the sole 4 by press working using a stamp. Furthermore, on the back surface of the head 1, logo marks 12 and 13 are formed on the top 4 and the cavity 9, respectively. These logo marks 12 and 13 are also formed as recesses on the back side of the top 4 and the back side inside the cavity 9 by pressing using a stamp.

  Next, the configuration of the score line 10 will be described in detail. FIG. 4 shows a groove 15 that is a score line 10 engraved on the face surface 14 (hereinafter referred to as a single groove) cut along a face perpendicular to the longitudinal direction of the face surface and the groove 15. It is a fragmentary sectional view. FIG. 4 shows a cross section of one groove 15, but the other grooves 15 are the same. The groove 15 basically has a width F of 0.035 inches (0.9 millimeters) or less and a depth G of 0.020 inches (0.508 millimeters) or less, and is symmetrical with respect to the center line of the groove. It is configured.

  The side wall 16 of the groove 15 has an inclined surface (tapered surface) whose width F becomes narrower on the bottom surface 17 side. Although the angle of the inclined surface is not shown, for example, the opening angle on one side is 10 degrees. The edge of the face surface 14 forms a convex portion 18, and the side wall 16 of the groove 15 forms a curved portion having a contour line 19 from the convex portion 18 to the side wall 16 of the groove 15. Is continuous from the side wall 16 of the groove 15 to the bottom surface 17 at the bottom. The depth G of the groove 15 up to the bottom surface 17 is limited in size so as to be 0.508 millimeters or less from the face surface 14.

  In the new rules, in addition to the above-mentioned rules for the width F and the depth G, the roundness of the edge of the face surface 14 and the groove 15 wall, that is, the configuration of the curved contour line 19 is also provided. In the present embodiment, in this rounded configuration, the spin effect is enhanced without impairing the contents of the new rules. Next, the specific shape will be described.

  FIG. 5 is an explanatory diagram showing an enlarged view of the portion H in FIG. In the shape of the edge portion of the face surface 14, the first circle “a” is an arc having a radius of 0.254 mm in contact with the face surface 14. The first circle a is a virtual circle set for specifying the shape. The second circle b is set to coincide with the center of the first circle a and is an arc having a radius of 0.2794 millimeters. This second circle b is also displayed as a virtual arc. The edge portion of the face surface 14 is configured as follows.

  Let C be the point where the face surface 14 and the second circle b intersect. A straight line is formed by setting a point C as a vertex, a straight line from the point C to the face surface 14 at a right angle, and a point intersecting the first circle a as a point D. Next, the curved portion as the contour line 19 with the point D as a base point is connected to the side wall 16 of the groove 15 within the space E between the first circle a and the second circle b, and the extension portion of the groove 15 A continuous groove wall is formed by reaching the bottom surface 17.

  The curved portion is traced to E between the first circle a and the second circle b as shown in the figure. As described above, the edge portion of the face surface 14 forms a convex portion 18 having an angle B = 90 degrees surrounded by the C point as an apex and surrounded between the face surface 14 and the straight line CD. The convex portion 18 is continuous with the curved portion. By constructing such a convex portion 18, the edge portion becomes a sharp corner portion, and the catch of the ball is improved and effective spin is given.

  The dimension A in the direction perpendicular to the face surface 14 of the straight line CD in this configuration is 0.028 millimeters. Thus, although the convex part 18 and the outline 19 are comprised, the vertex C does not necessarily need to be a point which cross | intersects the 2nd circle | round | yen b, Although not shown in figure, the 1st circle | round | yen a and 2nd It may be within E between circles b. The point D may also be within E between the first circle a and the second circle b. Therefore, if point C or point D is within E, dimension A will be less than 0.028 millimeters. Accordingly, the dimension A of 0.028 millimeters is the maximum value when the straight line CD forms 90 degrees on the face surface.

  FIG. 6 is an explanatory view similar to FIG. 5, but shows an example in which the angle of the straight line portion CD is changed from the point C of the edge portion of the face surface 14. FIG. 6 is an explanatory diagram in a case where a straight line CD having an angle B = 120 degrees from the point C to the face surface is shown. In this case, the straight line CD becomes a straight line inclined with respect to the face surface 14, and the length of the straight line CD becomes long. In this case, the dimension A in the direction perpendicular to the face surface 14 is 0.0428 millimeters. This is the maximum value when the angle B = 120 degrees.

  As described above, both the point C and the point D may be set within E, and the dimension A in that case is smaller than 0.0428 millimeters. Although not shown, the dimension A when the angle B = 110 degrees is 0.0354 millimeters. If the angle B exceeds 120 degrees, the sharpness of the point C is lacking, so the spin effect is reduced. Therefore, in consideration of workability, a range of 90 to 120 degrees is preferable. The shape of the edge portion of the face surface 14 related to the score line 10 has been described above. Next, a method for processing this shape will be described.

  The score line has a small shape and a small size. In the present embodiment, this shape is manufactured by machining. FIG. 7 shows a form of machining of the convex portion 18 and the contour line 19 by milling, grinding, or bite machining such as a total bite. In the case of milling, a general-purpose milling and grooving using a milling tool such as a groove milling machine, and similarly, in the case of grinding, a grinding tool such as a grindstone having a general shape is used.

  The shapes of these tools 20 are formed in accordance with the convex portion 18 and the contour line 19 of the groove 15. The tool 20 is a rotary tool regardless of whether it is milling or grinding. If the press work is performed on the groove 15, the tool 15 having a shape corresponding to the portion to be processed of the convex portion 18 and the contour line 19 is finished to finish the portion of the convex portion 18 and the contour line 19. If the press work is not performed, all the parts of the groove 15 are processed using the tool 20. FIG. 7 shows a form of all machining by the tool 20.

  The tool 20 is fed into the groove 15 while being rotated while being positioned, and moved in the longitudinal direction to process the entire length of the score line to the several grooves 15. In the case of FIG. 7, if the portion around the bottom surface 17 of the groove 15 is pressed, only the portion of the convex portion and the contour line (up to the two-dot chain line position) may be machined by the tool 20. By performing such processing, the convex portion 18 and the contour 19 are simultaneously processed into accurate dimensions.

  Further, although the tool has been described as a rotary tool, other embodiments may be shape machining with a cutting tool. Thus, the spin effect is stably achieved by processing the embossed portion 18 and the contour line 19 as an emphasis and forming an accurate and stable shape, that is, a sharp shape in this portion which is also an end portion of the contour line. As a result, the performance of the golf club is improved.

  As mentioned above, although each embodiment was described, it cannot be overemphasized that this invention is not limited to this embodiment. For example, in the description of the embodiment, the convex portions are formed independently, but a configuration in which a plurality of convex portions are formed may be used. Moreover, although the formation of the convex portion has been described by performing machining, it may be formed by performing precise pressing.

FIG. 1 is a front view of an iron golf club to which the present invention is applied. FIG. 2 is a rear view of an iron golf club to which the present invention is applied. FIG. 3 is a bottom view of an iron golf club to which the present invention is applied. FIG. 4 is a partial cross-sectional view showing the groove shape of the score line of the present invention. FIG. 5 is an enlarged explanatory view showing a portion H of FIG. 4 and shows a case where the angle B is 90 degrees. FIG. 6 is an enlarged explanatory view showing a portion H of FIG. 4 and shows a case where the angle B is 120 degrees. FIG. 7 is an explanatory view showing a processing mode of the groove.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Head 3 ... Face 10 ... Score line 14 ... Face surface 15 ... Groove 18 ... Convex part 19 ... Contour line 20 ... Tool

Claims (4)

A head body having a face (3) formed with several grooves (10, 15) having a toe heel direction as a longitudinal direction on the front surface and having a shaft mounting portion on one side, and connected to the shaft mounting portion In an iron golf club with a shaft,
In the cross section cut by the face perpendicular to the longitudinal direction of the face (14) and the groove (15) of the face (3), the outline (19) of the edge of the groove (15) is the face surface (14). ) And a first circle (a) having a radius of 0.010 inch (0.254 mm) in contact with the side surface of the groove (15);
This first circle (a) and the same center radius between the second circle (b) of 0.011 inch (0.2794 millimeters),
An iron golf club characterized in that a projecting convex portion (18) is formed in the vicinity of the edge of the groove (15). The iron golf club according to claim 1,
The said convex part (18) is formed adjacent to the said face surface (14). The iron golf club characterized by the above-mentioned. The iron golf club according to claim 1,
The said convex part (18) is an angle | corner which consists of 1 or more formed by two straight lines, and the angle B is 90 degrees <= B <= 120 degree. Iron golf club characterized by the above-mentioned. A method for producing an iron golf club according to claim 1 selected from claims 1 to 3,
The method of manufacturing an iron golf club, wherein the convex portion (18) is formed by shaping with a cutting tool, groove by milling with a rotary tool (20), or grinding with a grinding tool (20). .

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