JP2018011913A - Golf club head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase an initial velocity and a carry by securing a deflection amount of a sole part 18.SOLUTION: A sole part 18 enclosed by a first plane Pt, a second plane Ph, and a third plane Pb, includes a first low-rigidity area 32, a second low-rigidity area 34, and a high-rigidity area 36 formed from a leading edge 19 in a face-back direction with their aligned in this order. A wall thickness d1 of the first low-rigidity area 32 is larger than a wall thickness d2 of the second low-rigidity area 34, and a wall thickness d3 of the high-rigidity area 36 is equal to or more than the wall thickness d1 of the first low-rigidity area 32.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a golf club head.

It has been proposed to provide a weight portion at the sole portion near the face surface of the golf club head to reduce the position of the center of gravity on the face surface with a shallow center of gravity (see Patent Documents 1, 2, and 3).
However, when the weight portion is disposed on the sole portion close to the face surface, the rigidity of the portion of the sole portion where the weight portion is provided increases, so the amount of deflection of the sole portion decreases. Therefore, there is a disadvantage that the resilience of the golf club head is lowered and the effect of improving the flight distance is not obtained so much.
Therefore, a golf club head has been proposed in which the range in which the weight portion and the sole portion are fixed is limited so that the rigidity of the sole portion near the face portion does not become too high (see Patent Documents 4 and 5). ).

Patent No. 4902871 Patent No. 4226940 Japanese Patent No. 3663620 Japanese Patent No. 5852717 Patent No. 5842904

However, the above-described conventional technology has room for improvement from the viewpoint of securing a larger amount of deflection at the sole portion near the face portion.
The present invention has been made in view of such circumstances, and an object thereof is to provide a golf club head that is advantageous in securing the amount of deflection of the sole portion and increasing the initial speed and flight distance. is there.

In order to achieve the above object, a first aspect of the present invention is directed to a face portion constituting a face surface having a vertical height and extending left and right, and a crown extending rearward from an upper portion of the face portion. A back portion between a toe side edge and a heel side edge of the face portion between the crown portion and the sole portion, and a sole portion constituting a sole surface extending rearward from a lower portion of the face portion A golf club head comprising a head body including a side portion extending therethrough, the inside surrounded by the face portion, the crown portion, the sole portion, and the side portion being a hollow portion, wherein the golf club head In the reference state in which the lie angle and loft angle are set in advance with respect to the horizontal plane, the head book in a plane that includes a normal passing through the center point of the face surface and is orthogonal to the horizontal plane Is a face center reference section, a plane parallel to the face center reference section and 10 mm away from the face center reference section in the toe direction is a first plane, and is parallel to the face center reference section and the face center reference When the plane that is 10 mm away from the cross section in the heel direction is the second plane, and the plane that is orthogonal to the face center reference cross section and the horizontal plane and that is 50 mm away from the leading edge in the face back direction is the third plane, A first low-rigidity area, a second low-rigidity area, and a high-rigidity area are formed from the leading edge toward the faceback direction in the portion of the sole portion surrounded by the second plane and the third plane. , The thickness d1 of the first low-rigidity area is larger than the thickness d2 of the second low-rigidity area, and the high-rigidity Characterized in that the thickness d3 of the rear is the first low rigidity areas thickness d1 or more.
According to a second aspect of the present invention, in a face reference cross section in which the head main body is broken at an arbitrary plane parallel to the face center reference cross section, the face rear surface located on the opposite side of the face surface and the opposite side of the sole surface. A straight line that passes through a first boundary point that is a boundary point with the sole rear surface and that is orthogonal to the horizontal plane is defined as a first reference line L1, and is a boundary point between the first low-rigidity area and the second low-rigidity area. A straight line that passes through two boundary points and is orthogonal to the horizontal plane is defined as a second reference line L2, and a straight line that passes through a third boundary point that is a boundary point between the second low-rigidity area and the high-rigidity area is orthogonal to the horizontal plane. When the third reference line L3 is used, the first low-rigidity area is at least located within a range of 3 mm from the first reference line L1 in the face-back direction, and the second low-rigidity area is the second reference line. L2 is at least within a range of 3 mm in the face back direction, and the high rigidity area is at least within a range of 3 mm from the third reference line L3 in the face back direction, and the first low rigidity area The weighted average thickness Δd1 of the wall thickness d1, the weighted average value Δd2 of the wall thickness d2 of the second low rigidity area, and the weighted average value Δd3 of the wall thickness d3 of the high rigidity area are expressed by the following relational expression (1). (2) is satisfied.
0.5 ≦ (Δd2 / Δd1) <1 (1)
1 ≦ (Δd3 / Δd1) (2)
According to a third aspect of the present invention, a weight portion protrudes from the high-rigidity area toward the face portion, and a front end of the weight portion is located above the first low-rigidity area or above the second low-rigidity area. The weight portion is spaced apart from any of the face portion, the first low-rigidity area, and the second low-rigidity area.
The invention according to claim 4 extends in the toe heel direction and passes through at least one of a location above the first low-rigidity area and a location above the second low-rigidity area. A weight part joined to at least one of the sole part and the side part is provided, and the weight part is in any of the face part, the first low rigidity area, the second low rigidity area, and the high rigidity area. However, they are separated from each other.
According to a fifth aspect of the present invention, when the head main body is viewed in plan in the reference state, the width of the second low-rigidity area in the toe heel direction is 20 mm or more, and the face of the second low-rigidity area is The length along the direction connecting the part and the face back is 5 mm or more and 20 mm or less.
The weighted average value Δd1 of the wall thickness d1 of the first low-rigidity area is 1.0 mm or more and 2.0 mm or less, and the weighted average value Δd2 of the wall thickness d2 of the second low-rigidity area. Is 0.5 mm to 1.0 mm, and the weighted average value Δd3 of the thickness d3 of the high-rigidity area is 1.5 mm to 10 mm.
The thickness d1 of the first low-rigidity area is 0.7 mm or more and 2.0 mm or less, and the thickness d2 of the second low-rigidity area is 0.3 mm or more and 1.2 mm or less. The thickness d3 of the high-rigidity area is 1.5 mm or more and 10 mm or less.
The invention according to claim 8 is characterized in that the golf club head has a loft angle of 13 ° to 30 °, a volume of 100 cc to 200 cc, and a center of gravity depth of 10 mm to 18 mm.
According to a ninth aspect of the present invention, the face portion is provided with an opening that extends from an upper portion to a lower portion of the face portion and exposes a sole rear surface opposite to the sole surface to the front. And a face member that is joined to the opening by welding and closes the opening.
In the invention according to claim 10, the upper end of the opening is partitioned by the upper portion of the face portion, the lower end of the opening is partitioned by the sole surface of the front end of the sole portion, and the face member is It is inserted between the upper part and the front end of the sole part.
According to an eleventh aspect of the present invention, the sole portion includes a bottom wall facing the crown portion, and a front end of the bottom wall is located at a position displaced toward the face back side from the front end of the sole portion. The lower end of the face member constitutes the front end of the sole portion in a state where the face member is joined to the opening by welding and the opening is closed.

According to the first aspect of the present invention, the first low-rigidity area, the second low-rigidity area, and the high-rigidity area are arranged in this order from the leading edge toward the face back direction in the defined sole portion. And the thickness d1 of the first low-rigidity area is greater than the thickness d2 of the second low-rigidity area, and the thickness d3 of the high-rigidity area is greater than or equal to the thickness d1 of the first low-rigidity area 32. did.
Therefore, since the amount of deflection of the face portion can be secured by securing the amount of deflection of the sole portion closer to the leading edge, it is advantageous for increasing the initial speed and the flight distance, and the thickness d1 of the first low rigidity area is set to the first thickness. 2 It is advantageous to ensure durability by making it larger than the wall thickness d2 of the low rigidity area.
According to the invention described in claim 2, it is advantageous to enhance the effect of claim 1.
According to the third and fourth aspects of the invention, since the center of gravity of the golf club head can be lowered, it is more advantageous in increasing the flight distance.
According to the invention of Claims 5, 6, 7, and 8, it is advantageous to enhance the effect of Claim 1.
According to the ninth, tenth, and eleventh aspects of the invention, the amount of deflection of the face portion close to the leading edge can be secured, which is more advantageous in increasing the flight distance. Further, when the weight portion protrudes from the sole portion, it is easy to remove the core during casting, which is advantageous in improving productivity.

It is the front view which looked at the golf club head of a 1st embodiment from the front of the face side. It is A arrow directional view of FIG. It is a B arrow line view of FIG. It is CC sectional view taken on the line of FIG. It is a first explanatory view showing a method for defining the center point Pc of the face surface. It is the 2nd explanatory view showing the regulation method of center point Pc of a face surface. It is a 3rd explanatory view which shows the prescription | regulation method of center point Pc of a face surface. It is the 4th explanatory view showing the regulation method of center point Pc of a face surface. FIG. 3 is a cross-sectional view of a golf club head showing a relationship between a gravity center G0 of the golf club head and a gravity center FG on the face surface. It is a front view of the golf club head for explaining the definition of the contour line I of the face surface. It is sectional drawing of the golf club head explaining the definition of the outline I of a face surface. It is a front view of the golf club head explaining the definition of the center point Pc of the face surface. It is explanatory drawing which shows the deflection amount of the sole part at the time of a hit ball, (A) shows the deflection amount of the golf club head of 1st Embodiment, (B) shows the deflection amount of the conventional golf club head. It is a top view of the golf club head which shows prescription | regulation of a gravity center depth. It is sectional drawing in the face center reference | standard cross section of the golf club head of the 1st example of 2nd Embodiment. It is sectional drawing in the face center reference | standard cross section of the golf club head of the 2nd example of 2nd Embodiment. It is sectional drawing in the face center reference | standard cross section of the golf club head of the 1st example of 3rd Embodiment. It is sectional drawing in the face center reference | standard cross section of the golf club head of the 2nd example of 3rd Embodiment. It is sectional drawing in the face center reference | standard cross section of the golf club head of the 3rd example of 3rd Embodiment. It is A arrow line view of FIG. It is BB sectional drawing of FIG. It is a figure which shows the evaluation result of Experimental examples 1-13. It is a figure which shows the evaluation result of Experimental examples 1-13. It is a figure which shows the evaluation result of Experimental examples 14-25. It is a figure which shows the evaluation result of Experimental examples 14-25. It is a figure which shows the evaluation result of Experimental example 26-36. It is a figure which shows the evaluation result of Experimental example 26-36. FIG. 6A is a cross-sectional view of a golf club head according to a fourth embodiment in a cross-section of a face center, where FIG. 9A shows a state before a face member is attached to the opening, and FIG. Indicates the state. FIG. 10 is a cross-sectional view of a golf club head according to a fifth embodiment in a cross-section with reference to the center of the face, where (A) shows a state before a face member is attached to the opening, and (B) is a face welded to the opening. Indicates the state. It is sectional drawing explaining the lower end of the face part and the front end of a sole part in 4th, 5th embodiment. FIG. 4 is a cross-sectional view of a reference golf club head of a comparative example, with reference to a cross-section at the center of the face, where FIG. . It is a figure which shows the evaluation result of Experimental example 11, Experimental example 37, and Experimental example 38. FIG.

(First embodiment)
Next, embodiments of the present invention will be described.
As shown in FIGS. 1 to 4, in the present embodiment, the golf club head 10 is a hollow wood-type golf club head and includes a head body 12.
The head body 12 is mainly composed of a metal material.
As said metal material, 1 type (s) or 2 or more types, such as stainless steel, maraging steel, pure titanium, a titanium alloy, or an aluminum alloy, are used, for example.
The head body 12 includes a face portion 14, a crown portion 16, a sole portion 18, and a side portion 20.
The face portion 14 has a vertical height and extends to the left and right.
The crown portion 16 extends rearward from the upper portion of the face portion 14.
The sole portion 18 extends rearward from the lower portion of the face portion 14.
The side portion 20 extends between the crown portion 16 and the sole portion 18 through the face back 26 between the toe 22 side edge and the heel 24 side edge of the face portion 14.
The head body 12 has a hollow structure in which the inside surrounded by the face portion 14, the crown portion 16, the sole portion 18, and the side portion 20 is a hollow portion 28.
The surface exposed to the outside of the face portion 14 is a face surface 14A for hitting a ball, and the back surface facing the hollow portion 28 of the face portion 14 is a face back surface 14B.
The surface exposed to the outside of the crown portion 16 is a crown surface 16A.
The crown portion 16 is provided with a hosel 30 connected to the shaft S at a position near the heel 24 on the face surface 14A side.
The surface exposed to the outside of the sole portion 18 is a sole surface 18A, and the back surface facing the hollow portion 28 of the sole portion 18 is a sole back surface 18B.
In the figure, reference numeral 19 denotes a leading edge.

Next, a method for defining the center point Pc of the face surface 14A will be described.
The center point Pc of the face surface 14A is the geometric center of the face surface 14A, and the center point Pc is defined by various conventionally known methods including the first definition method and the second definition method exemplified below. The method can be adopted.

[A] First defining method of the center point Pc of the face surface 14A:
This is a method of defining the center point Pc when the boundary between the face surface 14A and another golf club head 10 portion is clear, in other words, when the periphery of the face surface 14A is specified by a ridgeline. In this case, the face surface 14A is clearly defined.
5 to 8 are explanatory views showing a method for defining the center point Pc of the face surface 14A.

(1) First, as shown in FIG. 5, the golf club head 10 is placed on the horizontal plane HP so that the lie angle and the face angle become specified values. The state of the golf club head 10 at this time is set as a reference state. Note that the set values of the lie angle and the face angle are values described in a product catalog, for example.

(2) Next, a temporary center point c0 in the direction connecting the crown portion 16 and the sole portion 18 is obtained.
That is, as shown in FIG. 5, a perpendicular line f0 is drawn that intersects the approximate center point of a line parallel to the horizontal plane HP connecting the toe 22 and the heel 24 (hereinafter referred to as a horizontal line).
The midpoint of the point a0 where the perpendicular f0 and the upper edge of the face surface 14A intersect and the midpoint of the point b0 where the perpendicular f0 and the lower edge of the face surface 14A intersect are defined as a temporary center point c0.

(3) Next, a horizontal line g0 passing through the temporary center point c0 is drawn as shown in FIG.
(4) Next, as shown in FIG. 7, the d0 point where the horizontal line g0 and the edge on the toe 22 side of the face surface 14A intersect, and the e0 point where the horizontal line g0 and the edge on the heel 24 side of the face surface 14A intersect. The midpoint is defined as a temporary center point c1.

(5) Next, as shown in FIG. 8, a perpendicular line f1 passing through the temporary center point c1 is drawn, and the perpendicular line f1 and the upper edge of the face surface 14A intersect with each other, the perpendicular line f1 and the lower edge of the face surface 14A. The midpoint of the b1 point where the two intersect is defined as the temporary center point c2.
Here, if the temporary center points c1 and c2 match, that point is defined as the center point Pc of the face surface 14A.
If the temporary center points c1 and c2 do not match, the procedures (2) to (5) are repeated.
Since the face surface 14A has a curved surface, the length of the horizontal line g0 and the lengths of the vertical lines f0 and f1 when obtaining the midpoint of the horizontal line g0 and the midpoints of the vertical lines f0 and f1 are the curved surfaces of the face surface 14A. The length along the line shall be used.
The face center line CL is defined by a straight line passing through the center point Pc and extending in a direction orthogonal to the toe 22-heel 24 direction.

[B] Second defining method of the center point Pc of the face surface 14A:
Next, the definition of the center point Pc when the periphery of the face surface 14A and the other golf club head 10 portions are connected by a curved surface and the face surface 14A cannot be clearly defined will be described.

As shown in FIG. 9, the golf club head 10 is hollow, the symbol G0 indicates the center of gravity of the golf club head 10, and the symbol Lp is a straight line connecting the center of gravity G0 and the center of gravity FG on the face surface, in other words. The straight line Lp is a perpendicular of the face surface 14A passing through the center of gravity G0.
That is, a point obtained by projecting the center of gravity G0 of the golf club head 10 onto the face surface 14A is the on-face center of gravity point FG.
Here, as shown in FIG. 10, a large number of planes H1, H2, H3,..., Hn including a straight line Lp connecting the center of gravity G0 and the on-face center of gravity FG are considered.

In a cross section when the golf club head 10 is broken along the planes H1, H2, H3,..., Hn, the curvature radius r0 of the outer surface of the golf club head 10 is measured as shown in FIG.
When measuring the curvature radius r0, it is assumed that there is no face line, punch mark or the like on the face surface 14A.
The curvature radius r0 is continuously measured from the center point Pc of the face surface 14A in the outward direction (upward and downward in FIG. 11).
Then, in the measurement, a portion where the radius of curvature r0 is initially equal to or smaller than a predetermined value is defined as an outline I representing the periphery of the face surface 14A.
The predetermined value is, for example, 200 mm.
A region surrounded by the contour line I determined based on a large number of planes H1, H2, H3,..., Hn is defined as a face surface 14A as shown in FIGS.

Next, as shown in FIG. 12, the golf club head 10 is placed on the horizontal ground (horizontal plane HP) so that the lie angle and the face angle become the prescribed values.
The straight line LT passes through the toe side point PT of the face surface 14A and extends in the vertical direction.
The straight line LH passes through the heel side point PH of the face surface 14A and extends in the vertical direction.
The straight line LC is parallel to the straight line LT and the straight line LH. The distance between the straight line LC and the straight line LT is equal to the distance between the straight line LC and the straight line LH.
Reference symbol Pu indicates an upper point of the face surface 14A, and reference symbol Pd indicates a lower point of the face surface 14A. The upper point Pu and the lower point Pd are both intersections of the straight line LC and the contour line I.
The center point Pc is defined by the midpoint of the line segment connecting the upper point Pu and the lower point Pd.

Next, the definition of each part of the golf club head 10 will be described in detail.
As shown in FIGS. 1 to 4, the golf club head 10 is set to a reference state in which the golf club head 10 is installed according to a predetermined lie angle and loft angle with respect to the horizontal plane HP.
As shown in FIGS. 1 and 3, in the reference state, a cross section in which the head body 12 is broken along a plane X that includes a normal passing through the center point Pc of the face surface 14A and is orthogonal to the horizontal plane HP is referred to as a face center reference section Pfc. To do. In other words, the face center reference cross section Pfc is a cross section in which the head body 12 is broken along a plane X including the face center line CL and orthogonal to the horizontal plane HP in the reference state.
Furthermore, a plane parallel to the face center reference section Pfc and separated from the face center reference section Pfc by 10 mm in the toe direction is defined as a first plane Pt.
A plane parallel to the face center reference section Pfc and separated from the face center reference section Pfc by 10 mm in the heel direction is defined as a second plane Ph.
A plane orthogonal to the face center reference cross section Pfc and the horizontal plane HP and separated from the leading edge 19 by 50 mm in the face back direction is defined as a third plane Pb.
A cross section in which the head body 12 is broken at an arbitrary plane parallel to the face center reference cross section Pfc is defined as a face reference cross section Pf. Therefore, the face reference cross section Pf includes the face center reference cross section Pfc.

As shown in FIG. 3 and FIG. 4, the first low rigidity toward the face back direction from the leading edge 19 to the portion of the sole portion 18 surrounded by the first plane Pt, the second plane Ph, and the third plane Pb. The area 32, the second low-rigidity area 34, and the high-rigidity area 36 are formed in this order.
As shown in FIG. 4, the thickness of the first low rigidity area 32 is d1, the thickness of the second low rigidity area 34 is d2, and the thickness of the high rigidity area 36 is d3.
The thickness d1 of the first low-rigidity area 32 is larger than the thickness d2 of the second low-rigidity area 34, and the thickness d3 of the high-rigidity area 36 is equal to or greater than the thickness d1 of the first low-rigidity area 32.
In other words, the rigidity of the first low-rigidity area 32 is higher than the rigidity of the second low-rigidity area 34, and the rigidity of the high-rigidity area 36 is greater than or equal to the rigidity of the first low-rigidity area 32.
Note that the thickness dx of the portion of the sole portion 18 excluding the first low-rigidity area 32, the second low-rigidity area 34, and the high-rigidity area 36 may be 0.5 mm or more and 1.5 mm or less. The thickness dx is the thickness of the portion excluding the ribs provided on the sole portion.

When a golf ball is hit with such a golf club head 10, stress in the face back direction acts on the portion of the sole portion 18 near the leading edge 19. Therefore, the first low rigidity area 32, the second low rigidity area 34, and the high rigidity Stress in the face back direction is applied to the area 36.
At this time, since the high-rigidity area 36 is located near the face back 26 of the first low-rigidity area 32 and the second low-rigidity area 34, the stress is sandwiched between the leading edge 19 and the high-rigidity area 36. Since the first low-rigidity area 32 and the second low-rigidity area 34 are concentrated and added, the first low-rigidity area 32 and the second low-rigidity area 34 bend more greatly than the high-rigidity area 36. .
As a result, this is advantageous in ensuring a large amount of deflection of the face portion 14 near the leading edge 19.
The first low-rigidity area 32 is a part connected to the face part 14 to which stress at the time of hitting is directly applied, so that a certain degree of strength is necessary to ensure durability.
On the other hand, since the second low-rigidity area 34 is separated from the face portion 14, durability can be ensured even if the strength is lower than that of the first low-rigidity area 32.
Therefore, in the present embodiment, the thickness d1 of the first low-rigidity area 32 is made larger than the thickness d2 of the second low-rigidity area 34, thereby ensuring the strength and durability of the first low-rigidity area 32. Is advantageous. Further, it is more advantageous to secure a large amount of deflection of the second low-rigidity area 34 by reducing the thickness d2 of the second low-rigidity area 34 while ensuring durability.
That is, since the deflection amount of the face portion 14 can be secured by securing the deflection amount of the sole portion 18 near the leading edge 19, it is advantageous for increasing the initial speed and the flight distance. Making the thickness d1 larger than the thickness d2 of the second low-rigidity area 34 is advantageous in ensuring durability.

FIG. 13 is an explanatory view showing the deflection amount of the sole portion at the time of hitting, (A) shows the deflection amount of the golf club head 10 of the first embodiment, and (B) shows the conventional golf club head 10. The amount of deflection of ′ is shown.
In the figure, reference numeral 2 denotes a ball, and the greater the hatching density drawn on the sole portion 14, the greater the deflection amount.
It can be seen that the golf club head 10 of the first embodiment has a larger amount of deflection of the sole portion 18 near the face portion 14 than the conventional golf club head 10.

Instead of defining the thickness of each of the first low-rigidity area 32, the second low-rigidity area 34, and the high-rigidity area 36 as described above, the entire thickness or most of the sole portion 18 is thinned. It is also conceivable to secure the deflection amount of the sole portion 18 by doing so.
However, in this case, the deflection of the portion of the sole portion 18 that is separated from the face portion 14 in the face back direction hardly contributes to the deflection of the face portion 14, so energy applied to the head body 12 at the time of hitting is wasted, and the face This is disadvantageous in securing the amount of deflection of the section 14. Further, it is disadvantageous in securing durability due to insufficient strength of the sole portion 18 near the leading edge 19.

In the present embodiment, as shown in FIGS. 1, 3, and 4, a cross section in which the head main body 12 is broken at an arbitrary plane parallel to the face center reference cross section Pfc is defined as a face reference cross section Pf.
At this time, as shown in FIG. 4, the first reference line L1, the second reference line L2, and the third reference line L3 are defined as follows in the face reference section Pf.
The first reference line L1 passes through a first boundary point K1 that is a boundary point between the face back surface 14B located on the opposite side of the face surface 14A and the sole back surface 18B located on the opposite side of the sole surface 18A, and is orthogonal to the horizontal plane HP. It is a straight line.
The second reference line L2 is a straight line that passes through the second boundary point K2, which is the boundary point between the first low-rigidity area 32 and the second low-rigidity area 34, and is orthogonal to the horizontal plane HP.
The third reference line L3 is a straight line that passes through the third boundary point K3 that is a boundary point between the second low-rigidity area 34 and the high-rigidity area 36 and is orthogonal to the horizontal plane HP.
In the present embodiment, the first boundary point K1, the second boundary point K2, and the third boundary point K3 are defined as follows.
The first boundary point K1 is defined as an intersection of a straight line passing through a portion 4 mm away from the leading edge 19 in the face back direction parallel to the horizontal plane HP and orthogonal to the horizontal plane HP and the sole back surface 18B. In other words, the straight line is the first reference line L1.
The second boundary point K2 measures the wall thickness of the sole portion 18 in order from the first boundary point K1 toward the face back side at an interval of 1 mm, compares the measured values in order, and starts with the maximum value. And the position of the sole back surface 18B having a value of less than 30%.
For the third boundary point K3, the thickness of the sole portion 18 is measured in order at intervals of 1 mm from the second boundary point K2 toward the face back side, the measured values are compared in order, and the maximum value is The sole back surface 18B has a value of 150% or more.

The first low-rigidity area 32 is at least located in a range from the first reference line L1 to 3 mm in the face back direction.
Further, the second low-rigidity area 34 is at least located in a range from the second reference line L2 to 3 mm in the face back direction.
Further, the high rigidity area 36 is at least located in a range from the third reference line L3 to 3 mm in the face back direction.
Then, the weighted average value Δd1 of the thickness d1 of the first low-rigidity area 32, the weighted average value Δd2 of the thickness d2 of the second low-rigidity area 34, and the weighted average value Δd3 of the thickness d3 of the high-rigidity area 36, Satisfies the following relational expressions (1) and (2).
0.5 ≦ (d2 / d1) <1 (1)
1 ≦ (d3 / d1) (2)
According to the above configuration, the positional relationship between the first low-rigidity area 32, the second low-rigidity area 34, and the high-rigidity area 36, and the weighted average value of the thickness are within an appropriate range, so that the amount of deflection of the face portion 14 is ensured. Thus, it is more advantageous for increasing the initial speed and the flight distance, and more advantageous for ensuring durability.
If the first low-rigidity area 32, the second low-rigidity area 34, and the high-rigidity area 36 are each less than the above 3 mm range, the effect of securing the deflection amount of the face portion 14 is reduced, and the initial speed and the flight distance are increased. The effect to aim at falls. Moreover, the effect of ensuring durability is reduced.
If the weighted average values Δd1, Δd2, and Δd3 of the thicknesses of the first low rigidity area 32, the second low rigidity area 34, and the high rigidity area 36 do not satisfy the relational expressions (1) and (2), The effect of securing the amount of deflection of the portion 14 is reduced, and the effect of increasing the initial speed and the flight distance is reduced. Moreover, the effect of ensuring durability is reduced.

The first low-rigid area 32 is preferably located in the range from 5 mm to at least 15 mm in the face back direction from the leading edge 19.
The second low-rigid area 34 is preferably located in the range from 7 mm to at least 30 mm in the face back direction from the leading edge.
The high-rigidity area 36 is preferably located adjacent to the second low-rigidity area 34 in the face-back direction and within a range of 50 mm or less from the leading edge 19 in the face-back direction.

In the present embodiment, as shown in FIG. 3, when the head main body 12 is viewed in plan in the reference state, the width WA in the toe heel direction of the second low-rigidity area 34 is 20 mm or more, and the second The length LA along the direction connecting the face portion 14 and the face back 26 of the low rigidity area 34 is not less than 5 mm and not more than 20 mm.
If the width WA of the second low-rigidity area 34 is less than 20 mm, the area of the second low-rigidity area 34 is too small, so that the effect of securing the deflection amount of the face portion 14 is reduced, and the initial speed and the flight distance are increased. The effect to aim at falls.
If the length LA of the second low-rigidity area 34 is less than the range of 5 mm or more and 20 mm or less, the area of the second low-rigidity area 34 is too small, so that the effect of securing the deflection amount of the face portion 14 is reduced. The effect of increasing the flight distance is reduced.
When the length of the second low-rigidity area 34 exceeds the range of 5 mm or more and 20 mm or less, the rear end of the second low-rigidity area 34 is too far away from the face portion 14 (leading edge 19). Part of the deflection becomes difficult to contribute to the deflection of the face portion 14, energy applied to the head body 12 at the time of hitting the ball is wasted, the effect of securing the deflection amount of the face portion 14 is reduced, and the initial speed and the flight distance are increased. The effect of aiming at is reduced.

In the present embodiment, the weighted average value Δd1 of the thickness d1 of the first low-rigidity area 32 is 1.0 mm or greater and 2.0 mm or less.
The weighted average value Δd2 of the wall thickness d2 of the second low rigidity area 34 is not less than 0.5 mm and not more than 1.0 mm.
The weighted average value Δd3 of the wall thickness d3 of the high rigidity area 36 is 1.5 mm or more and 10 mm or less.
In this way, the weighted average values of the thicknesses of the first low-rigidity area 32, the second low-rigidity area 34, and the high-rigidity area 36 are in a more appropriate range, so that the deflection amount of the face portion 14 is secured and the initial speed is increased. Further, it is more advantageous for increasing the flight distance, and more advantageous for ensuring durability.
Further, if the weighted average values Δd1, Δd2, and Δd3 of the thicknesses of the first low-rigidity area 32, the second low-rigidity area 34, and the high-rigidity area 36 do not satisfy the above definition, the amount of deflection of the face portion 14 is reduced. The effect of securing decreases, and the effect of increasing the initial speed and flight distance decreases. Moreover, the effect of ensuring durability is reduced.
The thickness d1 of the first low-rigidity area 32 is set to 0.7 mm or more and 2.0 mm or less, the thickness d2 of the second low-rigidity area 34 is set to 0.3 mm or more and 1.2 mm or less, and the thickness of the high-rigidity area is set. It is more preferable that d3 is 1.5 mm or more and 10 mm or less in order to secure the above effect.

In the present embodiment, the golf club head 10 has a loft angle θL of 13 ° to 30 °, a volume V of 100 cc to 200 cc, and a center of gravity depth GR of 10 mm to 18 mm.
As shown in FIG. 14, the center-of-gravity depth GR includes the center axis H0 of the insertion hole of the hosel 30 from the point G1 obtained by projecting the center of gravity G of the head body 12 onto the horizontal plane HP in the reference state of the golf club head 10. And a value defined by the shortest distance to the virtual plane KP perpendicular to the horizontal plane HP.
When the golf club head 10 satisfies the above-mentioned regulations, the head is rotated at the time of hitting so that the face surface faces upward, which is advantageous in obtaining a ball launch effect.
If the golf club head 10 does not satisfy the above definition, the effect of the face surface facing upward is reduced, and the effect is reduced.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIGS.
In the following embodiments, the same parts and members as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and description thereof is omitted.
In the second embodiment, in addition to the first embodiment, a weight portion 38 is provided at a location near the face portion 14 of the sole portion 18, and other configurations are the same as those of the first embodiment. It is.
In the second embodiment, as shown in FIGS. 15 and 16, a weight portion 38 is formed to project from the high rigidity area 36 toward the face portion 14.
The front end 3802 of the weight portion 38 may be located above the first low-rigidity area 32 as shown in FIG. 15, or located above the second low-rigidity area 34 as shown in FIG. You may do it.
Further, the weight portion 38 is separated from any of the face portion 14, the first low rigidity area 32, and the second low rigidity area 34.
Further, when viewed in plan in the reference state of the golf club head 10, the weight portion 38 intersects the face center reference cross section Pfc, and the dimension of the weight portion 38 in the toe heel direction is 20 mm or more and 60 mm or less.
According to such a configuration, in addition to the effects of the first embodiment, the center of gravity of the golf club head 10 can be lowered, which is more advantageous in increasing the flight distance.

The weight portion 38 is configured separately from the head main body 12 and may be fixed to the high-rigidity portion by various conventionally known methods such as welding, brazing, adhesion, and screwing. Alternatively, when casting the head main body 12, the weight portion 38 may be formed integrally with the high-rigidity portion.
When the weight portion 38 is configured separately from the high-rigidity portion 36 (head main body 12), the weight portion 38 may be formed of a material having a specific gravity greater than that of the material forming the head main body 12.
In this case, the material for forming the weight portion 38 is preferably a heavy metal such as Fe, Mo, Cu, Ag, Pb, Ta, W, Au, Pt, Ir, or an alloy containing one or more of these. Can be used.
When casting the head main body 12, when the weight portion 38 is formed integrally with the high-rigidity portion 36, the weight portion 38 has a shape protruding from the high-rigidity portion 36 (overhanging shape). There is concern that the mold will become complicated and the manufacturing cost will increase.
Therefore, it is advantageous to reduce the manufacturing cost by attaching the weight portion 38 to the sole portion 18 of the head body 12 formed separately from the weight portion 38 by retrofitting.

(Third embodiment)
Next, a third embodiment will be described with reference to FIGS.
In the third embodiment, as in the second embodiment, a weight portion 40 is provided at a location near the face portion 14 of the sole portion 18, but the weight portion 40 is provided in the first low rigidity area 32. These are joined to the portion of the sole portion 18 excluding the second low-rigidity area 34 and the high-rigidity area 36.
That is, as shown in FIGS. 17 to 19, the weight portion 40 extends in the toe heel direction and has at least one of a location above the first low stiffness area 32 and a location above the second low stiffness area 34. Both ends in the extending direction are joined to the sole portion 18.
That is, FIG. 17 shows a case where the weight portion 40 passes through a location above the second low rigidity area 34.
18 and 19 show a case in which the weight portion 40 passes through a location above the first low-rigidity area 32 and the second low-rigidity area 34, and the weight portion 40 in FIG. 19 is compared to FIG. Is located at a location deviated closer to the face portion 14.
FIG. 20 is a view as seen from the direction of arrow A in FIG.
21 is a cross-sectional view taken along line BB in FIG.
Note that both ends of the weight portion 40 in the extending direction may be joined to the side portion 20, or may be joined to both the sole portion 14 and the side portion 20.

The weight part 40 is separated from all of the face part 14, the first low rigidity area 32, the second low rigidity area 34, and the high rigidity area 36.
In addition to joining both ends of the weight part 40 in the extending direction to the sole part 18, the rear part of the weight part 40 near the face back 26 is made a part of the sole part 18 closer to the face back 26 than the high rigidity area 36. You may join.
Further, when viewed in plan in the reference state of the golf club head 10, the weight portion 40 intersects the face center reference cross section Pfc, and the dimension of the weight portion 40 in the toe heel direction is 20 mm or more and 60 mm or less.
According to such a configuration, an effect similar to that of the second embodiment is achieved.
Similarly to the second embodiment, the weight portion 40 may be configured separately from the head main body 12 and may be fixed to the sole portion 18. When the head main body 12 is cast, the weight portion 40 is used. May be formed integrally with the sole portion 18.
However, in the second embodiment, it is advantageous to reduce the manufacturing cost by fixing the weight portion 40 to the sole portion 18 of the head body 12 formed separately from the weight portion 40 by retrofitting. It is the same.
Furthermore, in the second embodiment, for example, even if the weight portion 40 is joined to the high-rigidity portion 36 by welding, the operation is not easy because the welding is performed inside the head body 12, whereas the third embodiment In this embodiment, when the weight portion 40 is welded to the sole portion 18, spot welding can be easily performed from the sole surface 18A side in a state in which the weight portion 40 is positioned on the sole back surface 18B. This is more advantageous for reduction.

Hereinafter, experimental examples of the present invention will be described.
22 to 27 are diagrams showing experimental results of the golf club head 10 according to the present invention.
A golf club head 10 as a sample was prepared for each experimental example, and the following three evaluation items were measured to obtain an index (evaluation point), and a total score of the three indices was obtained.

(1) Initial Speed A golf club equipped with the golf club head 10 was installed in a swing robot, and an actual hit test was performed under the following conditions, and the average value of the initial speed at 9 points was evaluated by an index. The index of Experimental Example 1 is 100, and the larger the index, the faster the initial speed and the better the evaluation.
Head speed: 40m / s
The hitting positions were 9 hits in total, and the ball was hit 5 times at each hitting point.
Three strike points: a center point Pc of the face surface 14A, a point separated by 7 mm from the center point Pc in the toe direction on a straight line passing through the center point Pc and orthogonal to the face center line CL, and a point separated by 7 mm in the heel direction.
On the face center line CL, a point 5 mm away from the center point Pc in the direction of the crown portion 16, a point 5 mm away from the above point in the toe direction on the upper 5 mm line passing through this point and orthogonal to the face center line CL, 3 strike points, 7mm apart in the heel direction.
On the face center line CL, a point 5 mm away from the center point Pc in the direction of the sole 1818, and a point 5 mm away from the above point in the toe direction on the lower 5 mm line passing through this point and orthogonal to the face center line CL; 3 strike points, 7mm apart in the heel direction.

(2) Flying distance The flying distance obtained in the actual hit test at the hit point position in the initial speed test was measured.
The index of Experimental Example 1 is set to 100, and the greater the index, the longer the flight distance and the better the evaluation.

(3) Durability A golf ball is repeatedly applied with an air cannon to the face surface 14A of the golf club head 10 fixed to the shaft, and the number of hits required until the face part 14 is deformed or damaged is measured. Was indexed. The ball speed was 50 m / s. The hit point position was set to the center point Pc of the face surface 14A.
In this case, the measurement result of the golf club head 10 of Experimental Example 1 is shown as an index with 100 as the measurement result. The larger the index, the better the evaluation.

(4) Total score The total score is the sum of the above-mentioned three indices of initial speed, flight distance, and durability.
The total score of Experimental Example 1 is 300, and the larger the total score, the better the evaluation.

Next, experimental examples 1 to 36 will be described with reference to FIGS.
In Experimental Example 1, the first low-rigidity area 32, the second low-rigidity area 34, and the high-rigidity area 36 are not formed in the sole portion 18, and no weight portion is provided, which corresponds to a comparative example. Therefore, Experimental Example 1 does not satisfy the definition of claim 1 of the present invention.
Experimental examples 3, 4, and 27 to 30 are outside the scope of the present invention, and the thickness relationship of the first low-rigidity area 32, the second low-rigidity area 34, and the high-rigidity area 36 is defined in claim 1. The condition is not met.

Experimental Examples 2, 6, 8, 10, 13, 16, 19, 22, 25, 34, and 36 are within the scope of the present invention and satisfy the provisions of claims 1, 2, and 4-8.
Examples 5, 7, and 9 are within the scope of the present invention, but do not satisfy the definition of claim 2.
Experimental Example 11 satisfies the definitions of claims 1, 2, 3, and 5-8.
Examples 12, 14, and 15 are within the scope of the present invention, but do not satisfy the provisions of claim 5.
Examples 17, 18, 20, 21, 23, and 24 are within the scope of the present invention, but do not satisfy the provisions of claim 8.
Experimental example 26 is within the scope of the present invention, but does not satisfy the provisions of claims 3 and 4.
Experimental Example 31 is within the scope of the present invention, but does not satisfy the provisions of claims 2, 6, and 7.
Experimental example 32 is within the scope of the present invention, but does not satisfy the provisions of claims 2 and 6.
Experimental Examples 33 and 35 are within the scope of the present invention, but do not satisfy the provisions of Claims 6 and 7.

The experimental example 3 is outside the scope of the present invention, and the thickness d1 of the first low-rigidity area 32 is smaller than the thickness d2 of the second low-rigidity area 34. Does not meet.
Therefore, the initial speed is 90, the flight distance 103, and the durability 107 are 300 in total, and the initial speed is lower than that of Experimental Example 1.
This is because the resilience performance is lowered because the thickness d2 of the second low rigidity area 34 is large.

The experimental example 4 is outside the scope of the present invention, and the thickness d1 of the first low-rigidity area 32 is equal to the thickness d2 of the second low-rigidity area 34. Does not meet.
Accordingly, the initial speed 110, the flight distance 113, the durability 109, and the total 332 are obtained. Although all the evaluations exceed the experimental example 1, the evaluation is lower than the experimental example 2.
This is because the resilience performance is lowered because the thickness of the second low-rigidity area 34 is large.

Experimental example 2 is within the scope of the present invention and satisfies the provisions of claims 1, 2, 4-7.
Therefore, the initial speed 132, the flight distance 133, the durability 134, and a total of 399 are obtained, and all evaluations exceed the experimental example 1, and the evaluation is the best among all the experimental examples.

Experimental example 5 is within the scope of the present invention, but the first low-rigidity area 32 is located in the range from the first reference line L1 to 5 mm in the face-back direction, which exceeds the 3 mm specification of claim 2. .
Therefore, the initial speed is 100, the flight distance is 102, the durability is 106, and the total is 308, and all the evaluations are lower than the experimental example 2.
This is because the first low-rigidity area 32 is located far from the leading edge 19 and the effect of improving the resilience performance is reduced.

Although Experimental Example 6 is within the scope of the present invention, the first low-rigidity area 32 is located in the range from the first reference line L1 to 3 mm in the face-back direction, and the upper limit value of 3 mm defined in claim 2 is used. is there.
Therefore, the initial speed 113, the flight distance 113, and the durability 109 are 337 in total, and all evaluations are higher than those in Experimental Example 1 but are lower than those in Experimental Example 2.
This is because the distance from the second low rigidity area 34 to the leading edge 19 is 3 mm, and the effect of improving the resilience performance is slightly reduced.

Experimental example 7 is within the scope of the present invention, but the second low-rigidity area 34 is located in the range from the second reference line L2 to 5 mm in the face back direction, which exceeds the 3 mm specification of claim 2. .
Therefore, the initial speed is 100, the flight distance is 100, the durability is 105, and the total is 305.
This is because the effect of improving the resilience performance is lowered because the second low-rigidity area 34 is located far from the leading edge 19.

Experimental Example 8 is within the scope of the present invention, and the second low-rigidity area 34 is located in the range from the second reference line L2 to 3 mm in the face-back direction, and is the specified upper limit value of 3 mm of claim 2. .
Therefore, the initial speed 106, the flight distance 104, the durability 110, and a total of 320 are obtained.
This is because the second low-rigidity area 34 is slightly away from the leading edge 19 from the second reference line L2, and the effect of improving the resilience performance is slightly reduced.

Although Experimental Example 9 is within the scope of the present invention, the high-rigidity area 36 is located in the range from the third reference line L3 to 4 mm in the face back direction, which exceeds the 3 mm specification of claim 2.
Therefore, the initial speed is 100, the flying distance is 100, the durability is 106, and the total is 306.
This is because the high rigidity area 36 is separated from the leading edge 19 and the effect of improving the resilience performance is slightly reduced.

Experimental Example 10 is within the scope of the present invention, and the high-rigidity area 36 is located in the range from the third reference line L3 to 3 mm in the face back direction, and is the prescribed upper limit value of 3 mm of claim 2.
Therefore, the initial speed 106, the flight distance 106, the durability 111, and the total 323 are obtained, and all evaluations are higher than those in Experimental Example 1 but lower than those in Experimental Example 2.
This is because the high rigidity area 36 is slightly separated from the leading edge 19 and the effect of improving the resilience performance is slightly reduced.

Experimental example 11 is within the scope of the present invention, and the weight portion 38 is formed to protrude from the high-rigidity area 36 and satisfies the definition of claim 3.
Therefore, the initial speed 131, the flying distance 134, the durability 131, and the total 396 are obtained. All the evaluations are higher than those in Experimental Example 1 and are equivalent to the evaluations in Experimental Example 2 although the shapes of the weight portions are different.

Experimental example 12 is within the scope of the present invention, and the width WA in the toe heel direction of the second low-rigidity area 34 is 18 mm, which is less than the prescribed 20 mm of claim 5.
Therefore, the initial speed 106, the flight distance 105, the durability 122, and the total 333 are obtained.
This is because the area of the second low-rigidity area 34 is slightly small, and the effect of improving the resilience performance is slightly reduced.

Experimental example 13 is within the scope of the present invention, and the width WA in the toe heel direction of the second low-rigidity area 34 is 20 mm, which satisfies the prescribed 20 mm of claim 5.
Therefore, the initial speed is 110, the flying distance is 111, the durability is 125, and the total is 346.
This is because the area of the second low-rigidity area 34 is secured, and the effect of improving the resilience performance is secured.

Experimental Example 14 is within the scope of the present invention, but the length along the direction connecting the face portion 14 and the face back of the second low-rigidity area 34 is 4 mm, and the length is 5 mm or more and 20 mm or less according to claim 5. Below regulation.
Therefore, the initial speed 105, the flight distance 106, the durability 123, and the total 334 are obtained.
This is because the area of the second low-rigidity area 34 is slightly small, and the effect of improving the resilience performance is slightly reduced.

Experimental Example 15 is within the scope of the present invention, but the length along the direction connecting the face portion 14 and the face back of the second low-rigidity area 34 is 23 mm, and the length is 5 mm or more and 20 mm or less according to claim 5. It exceeds the regulations.
Accordingly, the initial speed 108, the flight distance 107, and the durability 120 are 335 in total, and all the evaluations are higher than the experimental example 1, but the evaluation is lower than the experimental example 2.
This is because the second low-rigidity area 34 is separated from the leading edge 19 in the face-back direction, and the effect of improving the resilience performance is slightly reduced.

Experimental example 16 is within the scope of the present invention, and the length along the direction connecting the face portion 14 and the face back of the second low-rigidity area 34 is 5 mm, and is defined as 5 mm to 20 mm in claim 5. Is the lower limit of.
Therefore, the initial speed 114, the flight distance 112, the durability 123, and the total 349 are obtained, and all evaluations are lower than those in Experimental Example 2, but are higher than those in Experimental Example 14.
This is because the area of the second low-rigidity area 34 is secured to some extent, and the effect of improving the resilience performance is secured.

Although the experiment example 17 is within the scope of the present invention, the loft angle is 12 °, which is less than the definition of 13 ° to 30 ° in claim 8.
Therefore, the initial speed is 128, the flying distance is 110, and the durability is 115, and the total is 353. Although all evaluations are superior to Experimental Example 1, the evaluation of the flying distance and durability is not so high as compared with the initial speed.
This is because the ball launch angle is low and the stress applied to the face portion 14 is slightly large.

Experimental Example 18 is within the scope of the present invention, but has a loft angle of 31 °, which exceeds the definition of 13 ° to 30 ° in claim 8.
Therefore, the initial speed 114, the flight distance 113, and the durability 126 are 353 in total, and all evaluations are superior to those of Experimental Example 1, but the evaluation of the initial speed and the flight distance is not so high as compared with the durability.
This is because the loft angle is large and the ball launch angle is high, and the stress applied to the face portion 14 is slightly small.

Experimental Example 19 is within the scope of the invention, has a loft angle of 13 °, and is the prescribed lower limit of 13 ° to 30 ° of claim 8.
Therefore, the initial speed 129, the flight distance 116, and the durability 126 are 371 in total, and all evaluations are superior to those of Experimental Example 1, but the evaluation of the flight distance is not so high compared to the initial speed and durability.
This is because the loft angle is the lower limit value, so the ball launch angle is low, and the stress applied to the face portion 14 is slightly large.

Although Experimental Example 20 is within the scope of the invention, the volume is 90 cc, which is less than 100 cc or more and 200 cc or less.
Therefore, the initial speed 116, the flight distance 117, and the durability 128 are 361 in total, and all evaluations are superior to Experimental Example 1, but the evaluation of the initial speed and the flight distance is not so high as compared with the durability.
This is because, since the golf club head 10 is small, the golfer feels a little uncomfortable when holding the golfer, and the effect of smoothly swinging is reduced.

Although Experimental Example 21 is within the scope of the invention, the volume is 210 cc, which exceeds the specification of 100 cc to 200 cc in claim 8.
Accordingly, the initial speed 115, the flight distance 117, and the durability 127 are 359 in total, and all evaluations are superior to those of Experimental Example 1, but the evaluation of the initial speed and the flight distance is not so high as compared with the durability.
This is because the golf club head 10 is large, so that the golfer feels a little uncomfortable when holding the golfer, and the effect of smoothly swinging is reduced.

Experimental example 22 is within the scope of the invention, has a volume of 100 cc, and is the specified lower limit of 100 cc to 200 cc of claim 8.
Therefore, the initial speed 121, the flight distance 120, the durability 128, and the total 369 are obtained. Although all the evaluations are superior to the experimental example 20, the evaluation is lower than the experimental example 2.
This is because the golf club head 10 is slightly small, so that the golfer feels a little uncomfortable when holding it, and the effect of smoothly swinging is slightly reduced.

Although Experimental Example 23 is within the scope of the invention, the center-of-gravity depth GR is 9 mm, which is less than 10 mm or more and 18 mm or less.
Accordingly, the initial speed 129, the flight distance 111, and the durability 115 are 355 in total, and all evaluations are superior to Experimental Example 1, but the evaluation of the flight distance and durability is not so high compared to the initial speed.
This is because the center of gravity is shallow and the launch angle of the ball is low, so the effect of securing the flight distance is slightly reduced.

Although Experimental Example 24 is within the scope of the invention, the center-of-gravity depth GR is 20 mm, which exceeds the specification of 10 mm to 18 mm in claim 8.
Therefore, the initial speed 111, the flying distance 112, and the durability 128 are 351 in total, and all the evaluations are superior to the experimental example 1, but the evaluation of the initial speed and the flying distance is not so high compared to the durability. .
Since the center of gravity is deep and the golf club head 10 is deviated in the direction of increasing the loft angle at the time of hitting, the initial speed is slightly reduced, and the launch angle of the ball becomes too high and the flight distance is secured. This is because it slightly decreases.

Experimental Example 25 is within the scope of the invention, and the center-of-gravity depth GR is 10 mm, which is the specified lower limit value of 10 mm to 18 mm in claim 8.
Therefore, the initial speed is 120, the flying distance is 121, the durability is 127, and the total is 368. Although all evaluations are superior to Experimental Example 23, the evaluation is lower than Experimental Example 2.
This is because the center of gravity is shallow and the launch angle of the ball is low, so the effect of securing the flight distance is slightly reduced.

Experimental Example 26 is within the scope of the present invention, but does not have a weight portion and does not satisfy the provisions of claims 3 and 4.
Therefore, the initial speed 126, the flying distance 110, the durability 115, and the total 351 are obtained, and although all evaluations are superior to the experimental example 1, the evaluation of the flying distance compared to other experimental examples having a weight portion. Is not so expensive.
This is because, since there is no weight portion, the effect of lowering the center of gravity is reduced, and the effect of securing the flight distance is slightly reduced.

The experimental example 27 is outside the scope of the present invention, and the magnitude relationship between the thickness d1 of the first low-rigidity area 32, the thickness d2 of the second low-rigidity area 34, and the thickness d3 of the high-rigidity area 36 of claim 1. Does not meet the provisions.
The ratio (d2 / d1) of the weighted average value Δd1 of the thickness d1 of the first low-rigidity area 32 and the weighted average value Δd2 of the thickness d2 of the second low-rigidity area 34 is 0.4, 2 is less than 0.5 ≦ (d2 / d1) <1.
Further, the weighted average value Δd1 of the thickness d1 of the first low-rigidity area 32 is 2.1 mm, which exceeds the range of 1.0 mm to 2.0 mm in claim 6.
Further, the thickness d1 of the first low-rigidity area 32 is 2.1 mm, which exceeds the range of 0.7 mm to 2.0 mm in claim 7.
Accordingly, the initial speed 92, the flight distance 92, and the durability 119 are 303 in total, and the evaluation excluding the durability is lower than the experimental example 1.
This is because the effect of securing the deflection amount of the face portion 14 is low.

The experimental example 28 is outside the scope of the present invention, and the thickness d1 of the first low-rigidity area 32 and the thickness d2 of the second low-rigidity area 34 of claim 1 are equal, and the magnitude relation of claim 1 is defined. Does not meet.
The ratio (d2 / d1) of the weighted average value Δd1 of the thickness d1 of the first low-rigidity area 32 and the weighted average value Δd2 of the thickness d2 of the second low-rigidity area 34 is 0.4, 2 is less than 0.5 ≦ (d2 / d1) <1.
The weighted average value Δd1 of the thickness d1 of the first low-rigidity area 32 is 2.0 mm, which is the upper limit value in the range of 1.0 mm to 2.0 mm.
The thickness d1 of the first low-rigidity area 32 is 2 mm, which is the upper limit value in the range of 0.7 mm to 2.0 mm in claim 7.
Therefore, the initial speed 109, the flight distance 108, and the durability 123 are 340 in total, and the durability is superior to that of Experimental Example 1, but the other evaluations are only slightly higher than Experimental Example 1.
This is because the effect of securing the deflection amount of the face portion 14 is low.

The experimental example 29 is outside the scope of the present invention, and the thickness d2 of the second low-rigidity area 34 is larger than the thickness d1 of the first low-rigidity area 32 of claim 1, and the magnitude relation of claim 1 is defined. Does not meet.
The ratio (d2 / d1) of the weighted average value Δd1 of the wall thickness d1 of the first low-rigidity area 32 and the weighted average value Δd2 of the wall thickness d2 of the second low-rigidity area 34 is 1.4, 2 exceeds the range of 0.5 ≦ (d2 / d1) <1.
Further, the weighted average value Δd1 of the thickness d1 of the first low-rigidity area 32 is 0.6 mm, which is less than the range of 1.0 mm to 2.0 mm in claim 6.
Further, the thickness d1 of the first low-rigidity area 32 is 0.6 mm, which is less than the range of 0.7 mm to 2.0 mm in claim 7.
Therefore, the initial speed 115, the flight distance 114, and the durability 82 are 311 in total, and the evaluation of the initial speed and the flight distance is superior to that of Experimental Example 1, but the evaluation of durability is low.
This is because the thickness d1 of the first low-rigidity area 32 is thin.

The experimental example 30 is outside the scope of the present invention, and the wall thickness d2 of the second low-rigidity area 34 is larger than the wall thickness d1 of the first low-rigidity area 32 of claim 1, and the magnitude relation of claim 1 is defined. Does not meet.
The ratio (d2 / d1) of the weighted average value Δd1 of the wall thickness d1 of the first low-rigidity area 32 and the weighted average value Δd2 of the wall thickness d2 of the second low-rigidity area 34 is 1.2, 2 exceeds the range of 0.5 ≦ (d2 / d1) <1.
Further, the weighted average value Δd1 of the thickness d1 of the first low-rigidity area 32 is 0.7 mm, which is below the range of 1.0 mm to 2.0 mm in claim 6.
The thickness d1 of the first low-rigidity area 32 is 0.7 mm, which is the lower limit value in the range of 0.7 mm to 2.0 mm.
Therefore, the initial speed 114, the flight distance 114, and the durability 86 are 314 in total, and the evaluation of the initial speed and the flight distance is superior to that of Experimental Example 1, but the evaluation of the durability is low.
This is because the thickness d1 of the first low-rigidity area 32 is thin.

Although the experimental example 31 is within the scope of the present invention, the ratio (d2) of the weighted average value Δd1 of the wall thickness d1 of the first low-rigidity area 32 and the weighted average value Δd2 of the wall thickness d2 of the second low-rigidity area 34 / D1) is 0.2, which is lower than the range of 0.5 ≦ (d2 / d1) <1.
The weighted average value Δd2 of the thickness d2 of the second low-rigidity area 34 is 0.2 mm, which is less than the range of 0.5 mm to 1.0 mm in claim 6.
Further, the thickness d2 of the second low-rigidity area 34 is 0.2 mm, which is less than the range of 0.3 mm to 1.2 mm in claim 7.
Therefore, the initial speed 113, the flight distance 114, and the durability 85 are 312 in total, and the evaluation of the initial speed and the flight distance is superior to that of Experimental Example 1, but the evaluation of the durability is low.
This is because the thickness d2 of the second low rigidity area 34 is thin.

The experimental example 32 is within the scope of the present invention, but the ratio (d2) / D1) is 0.3, which is lower than the range of 0.5 ≦ (d2 / d1) <1 of claim 2.
Further, the weighted average value Δd2 of the thickness d2 of the second low-rigidity area 34 is 0.3 mm, which is below the range of 0.5 mm to 1.0 mm in claim 6.
The thickness d2 of the second low-rigidity area 34 is 0.3 mm, which is the lower limit value in the range of 0.3 mm to 1.2 mm.
Therefore, the initial speed 112, the flight distance 113, the durability 89, and the total 314 are obtained, and the evaluation is superior to the experimental example 1 except for the durability.
This is because the thickness d2 of the second low rigidity area 34 is thin.

Experimental example 33 is within the scope of the present invention, and is the ratio (d2 / d1) is 0.7, which satisfies the range of 0.5 ≦ (d2 / d1) <1.
Further, the weighted average value Δd3 of the wall thickness d3 of the high-rigidity area 36 is 11 mm, which exceeds the range of 1.5 mm to 10 mm in claim 6.
Further, the thickness d3 of the high-rigidity area 36 is 11 mm, which exceeds the range of 1.5 mm to 10 mm in claim 7.
Therefore, the initial speed 124, the flight distance 124, and the durability 94 are 342 in total, and the evaluation of the initial speed and the flight distance is superior to that of Experimental Example 1, but the evaluation of the durability is low.
This is because the thickness d3 of the high-rigidity area 36 is thick, so that the difference from the thickness d2 of the second low-rigidity area 34 is large, and stress is easily concentrated.

The experimental example 34 is within the scope of the present invention, and the ratio (d2 // d1) is 0.7, which satisfies the range of 0.5 ≦ (d2 / d1) <1.
The weighted average value Δd3 of the wall thickness d3 of the high-rigidity area 36 is 10 mm, which is the upper limit value in the range of 1.5 mm to 10 mm.
Further, the thickness d3 of the high-rigidity area 36 is 10 mm, which is the upper limit value in the range of 1.5 mm to 10 mm.
Therefore, the initial speed 126, the flying distance 125, the durability 109, and the total 360 are obtained, and all evaluations are superior to the experimental example 35.
This is because the thickness d3 of the high-rigidity area 36 is set to an appropriate range.

The experimental example 35 is within the scope of the present invention, and the ratio (d2 / d1) is 0.7, which satisfies the range of 0.5 ≦ (d2 / d1) <1.
Further, the weighted average value Δd3 of the thickness d3 of the high-rigidity area 36 is 1.4 mm, which is below the range of 1.5 mm to 10 mm in claim 6.
Further, the thickness d3 of the high-rigidity area 36 is 1.4 mm, which is less than the range of 1.5 mm to 10 mm in claim 7.
Therefore, the initial speed 126, the flight distance 125, and the durability 96 are 347 in total, and the evaluation of the initial speed and the flight distance is superior to that of Experimental Example 1, but the evaluation of the durability is low.
This is because the thickness d3 of the high-rigidity area 36 is thin, and the effect of securing the deflection amount of the sole portion 18 is reduced.

Experimental example 36 is within the scope of the present invention, and the ratio of the weighted average value Δd1 of the thickness d1 of the first low-rigidity area 32 to the weighted average value Δd2 of the thickness d2 of the second low-rigidity area 34 (d2 / d1) is 0.7, which satisfies the range of 0.5 ≦ (d2 / d1) <1.
The weighted average value Δd3 of the thickness d3 of the high-rigidity area 36 is 1.5 mm, which is the lower limit value in the range of 1.5 mm to 10 mm.
Further, the thickness d3 of the high-rigidity area 36 is 1.5 mm, which is the lower limit value in the range of 1.5 mm to 10 mm.
Therefore, the initial speed is 129, the flight distance is 128, the durability is 101, and the total is 358, and all the evaluations are superior to the experimental example.
This is because the thickness d3 of the high-rigidity area 36 is set to an appropriate range.

Each evaluation item is examined below.
(1) Initial speed Experimental examples 2, 6, 8, 10, 13, 16, 19, 22, 25, 34, 36, which are within the scope of the present invention and satisfy the provisions of claims 1, 2, 4 to 8, and , Claims 1, 2, 3, and 5 to 8 have the initial speed of 106 to 132, and the initial speed is the best.
In the experimental examples 5, 7, and 9, which are within the scope of the present invention but do not satisfy the definition of claim 2, the initial speed is 100.
In Experimental Example 26, which falls within the scope of the present invention but does not satisfy the provisions of claims 3 and 4, the initial speed is 126.
In Experimental Examples 12, 14, and 15, which are within the scope of the present invention but do not satisfy the definition of claim 5, the initial speed is 105 to 108.
In the experimental example 31, which is within the scope of the present invention but does not satisfy the provisions of claims 2, 6 and 7, the initial speed is 113.
In Experimental Example 32, which falls within the scope of the present invention but does not satisfy the provisions of claims 2 and 6, the initial speed is 112.
In the experimental examples 33 and 35 that do not satisfy the provisions of claims 6 and 7 within the scope of the present invention, the initial speeds are 124 and 126, respectively.
In the experimental examples 17, 18, 20, 21, 23, and 24, which are within the scope of the present invention but do not satisfy the definition of claim 8, the initial speed is 111 to 129.
Therefore, what satisfies the provisions of claims 1, 2, 4 to 8 or claims 1, 2, 3, 5 to 8 within the scope of the present invention is outside the scope of the present invention. The effect of improving the initial speed is excellent.

(2) Flight distance Examples 2, 6, 8, 10, 13, 16, 19, 22, 25, 34, 36, which are within the scope of the present invention and satisfy the provisions of claims 1, 2, 4 to 8. And Experimental example 11 which satisfy | fills prescription | regulations of Claims 1, 2, 3, and 5-8 has the flying distance of 104-133, and the flying distance is the most excellent.
In the experimental examples 5, 7, and 9, which are within the scope of the present invention but do not satisfy the definition of claim 2, the flight distances are 100 and 102.
Experimental example 26, which is within the scope of the present invention but does not satisfy the provisions of claims 3 and 4, has a flight distance of 110.
In the experimental examples 12, 14, and 15 that fall within the scope of the present invention but do not satisfy the provisions of claim 5, the flight distance is 105 to 108.
In the experimental example 31, which is within the scope of the present invention but does not satisfy the provisions of claims 2, 6 and 7, the flight distance is 114.
The experimental example 32 which is within the scope of the present invention but does not satisfy the provisions of claims 2 and 6 has a flight distance of 113.
In the experimental examples 33 and 35 that do not satisfy the provisions of claims 6 and 7 within the scope of the present invention, the flight distances are 124 and 125, respectively.
The experimental examples 17, 18, 20, 21, 23, and 24, which are within the scope of the present invention but do not satisfy the provisions of claim 8, have a flight distance of 110 to 117.
Therefore, what satisfies the provisions of claims 1, 2, 4 to 8 or claims 1, 2, 3, 5 to 8 within the scope of the present invention is outside the scope of the present invention. The effect of improving the flight distance is excellent.

(3) Durability Experimental Examples 2, 6, 8, 10, 13, 16, 19, 22, 25, 34, 36, which are within the scope of the present invention and satisfy the provisions of claims 1, 2, 4 to 8. And Experimental example 11 which satisfy | fills prescription | regulation of Claims 1, 2, 3, and 5-8 has durability of 101-134, and durability is the most excellent.
Within the scope of the present invention, the experimental examples 5, 7, and 9 that do not satisfy the definition of claim 2 have durability of 105 and 106, respectively.
The experimental example 26 which is within the scope of the present invention but does not satisfy the provisions of claims 3 and 4 has a durability of 115.
Within the scope of the present invention, Experimental Examples 12, 14, and 15 that do not satisfy the definition of claim 5 have a durability of 120 to 123.
The experimental example 31 which is within the scope of the present invention but does not satisfy the provisions of claims 2, 6 and 7 has a durability of 85.
The experimental example 32 that falls within the scope of the present invention but does not satisfy the provisions of claims 2 and 6 has a durability of 89.
Within the scope of the present invention, Experimental Examples 33 and 35 that do not satisfy the provisions of Claims 6 and 7 have a durability of 94 and 96, respectively.
The experimental examples 17, 18, 20, 21, 23, and 24 that fall within the scope of the present invention but do not satisfy the definition of claim 8 have a durability of 115 to 128.
Therefore, what satisfies the provisions of claims 1, 2, 4 to 8 or claims 1, 2, 3, 5 to 8 within the scope of the present invention is outside the scope of the present invention. The effect of improving durability is excellent.

(4) Total score Examples 2, 6, 8, 10, 13, 16, 19, 22, 25, 34, 36, which are within the scope of the present invention and satisfy the provisions of claims 1, 2, 4 to 8. And the example 11 which satisfy | fills prescription | regulation of Claims 1, 2, 3, and 5-8 has a total score of 320-399, and a total score is the best.
In Experimental Examples 5, 7, and 9, which are within the scope of the present invention but do not satisfy the definition of claim 2, the total points are 305 to 308.
The total number of experimental examples 26 that fall within the scope of the present invention but do not satisfy the provisions of claims 3 and 4 is 351.
The total points of Experimental Examples 12, 14, and 15 that are within the scope of the present invention but do not satisfy the provisions of claim 5 are 333 to 335.
The total number of experimental examples 31 that fall within the scope of the present invention but do not satisfy the provisions of claims 2, 6, and 7 is 312.
In the experimental example 32 which is within the scope of the present invention but does not satisfy the provisions of claims 2 and 6, the total score is 314.
Within the scope of the present invention, Experimental Examples 33 and 35 that do not satisfy the provisions of Claims 6 and 7 have a total score of 342 and 347, respectively.
The total number of Experimental Examples 17, 18, 20, 21, 23, and 24 that are within the scope of the present invention but do not satisfy the definition of Claim 8 is 351 to 361.
Therefore, what satisfies the provisions of claims 1, 2, 4 to 8 or claims 1, 2, 3, 5 to 8 within the scope of the present invention is outside the scope of the present invention. The effect of improving the total score is excellent.

(Fourth embodiment)
Next, a fourth embodiment will be described with reference to FIG.
The fourth embodiment is a modification of the second embodiment, and is similar to the second embodiment in that a weight portion 38 is provided at a location near the face portion 14 of the sole portion 18.
That is, the weight portion 38 is formed to project from the high rigidity area 36 toward the face portion 14, and the front end 3802 of the weight portion 38 is located above the first low rigidity area 32 or the second low rigidity area 34. The weight portion 38 is separated from all of the face portion 14, the first low rigidity area 32, and the second low rigidity area 34.
In the fourth embodiment and the fifth embodiment, as shown in FIG. 30, the portion where the wall portion constituting the face surface 14A extends vertically is the face portion 14, and the sole surface 18A is formed. A portion where the wall portion extending forward and backward is the sole portion 18, and the lower end 1450 of the face portion 14 and the front end 1850 of the sole portion 18 overlap each other.

As shown in FIG. 28A, in the golf club head 10 according to the fourth embodiment, the face portion 14 extends from the upper portion of the face portion 14 toward the lower portion and is opposite to the sole surface 18A of the sole portion 18. An opening 42 is provided to expose the side sole rear surface 18B forward.
The upper end of the opening 42 is partitioned by the upper wall surface 1402 of the face portion 14, and the lower end of the opening 42 is partitioned by the sole back surface 18 </ b> B of the front end 1850 of the sole portion 18.
As shown in FIG. 28B, the face portion 14 includes a face member 44 that is joined to the opening portion 42 by welding and closes the opening portion 42, and the face member 44 is connected to the upper wall surface 1402 of the face portion 14. The sole portion 18 is inserted between the front end 1850 and the sole back surface 18B.
In the drawing, reference numerals B1 and B2 denote weld beads formed by welding the face member 44 to the opening 42.

Therefore, the weld bead B1 at the welded portion between the upper end 4402 of the face member 44 and the upper wall surface 1402 of the face portion 14 is formed on the face back surface 14B, and the sole back surface 18B of the front end 1850 of the sole member 18 The weld bead B2 at the weld location is formed at the corner where the face back surface 14B and the sole back surface 18B intersect.
Since the weld bead B1 is formed on the face back surface 14B, which is a continuous surface, the weld bead B1 is formed with a certain thickness, whereas the weld bead B2 is a corner portion where the face back surface 14B and the sole back surface 18B intersect. Therefore, the thickness thereof can be smaller than the thickness of the weld bead B1. This is because the thickness of the sole portion 18 is generally thinner than the thickness of the face portion 14, so that the output of an arc or laser during welding can be reduced. Therefore, the bead amount disposed on the inner surface of the head body 12 can be appropriately reduced.
Therefore, compared with the rigidity of the upper part of the face part 14 enhanced by the weld bead B1, the rigidity of the face part 14 near the leading edge 19 enhanced by the weld bead B2 is lower, and the rigidity of the face part 14 near the leading edge 19 is increased. This is advantageous in securing the amount of deflection, and is advantageous in improving the flight distance.
In particular, the golf club head 10 such as a fairway wood whose hit point is located near the lower portion of the face surface 14A is more advantageous in improving the flight distance.

Further, when the head main body 12 excluding the face member 44 is manufactured by casting, it is necessary to dispose a core between the weight portion 38 and the sole back surface 18B.
In the present embodiment, the opening 42 exposes the sole back surface 18B forward, and the lower end of the opening 42 is partitioned by the sole back surface 18B of the front end 1850 of the sole portion 18. Since the core and the lower end of the opening portion 42 do not interfere with each other when taking out from the container, it is advantageous in facilitating the work and advantageous in improving productivity.

(Fifth embodiment)
Next, a fifth embodiment will be described with reference to FIG.
The fifth embodiment is a modification of the fourth embodiment.
As shown in FIGS. 29A and 29B, as in the fourth embodiment, the face portion 14 extends from the upper portion of the face portion 14 toward the lower portion, and the sole surface 18A of the sole portion 18 An opening 42 for exposing the opposite sole rear surface 18B to the front is provided, and the face 14 includes a face member 44 that is joined to the opening 42 by welding and closes the opening 42.
In the fifth embodiment, the sole portion 18 includes a bottom wall 48 that constitutes the sole surface 18A, and the front end 4802 of the bottom wall 48 is displaced toward the face back 26 side relative to the front end 1850 of the sole portion 18. It is located in the place. More specifically, the front end 4802 of the bottom wall 48 is located at a location displaced from the front end of the sole portion 18 toward the face back 26 by the thickness of the face portion 14.
The lower end 4404 of the face member 44 constitutes the front end 1850 of the sole portion 18 and the front end of the sole surface 18A in a state where the face member 44 is joined to the opening 42 by welding and the opening 42 is closed.

Accordingly, the weld bead B1 at the welded portion between the upper end 4402 of the face member 44 and the upper wall surface 4202 of the face portion 14 is formed on the face back surface 14B, and the welded portion between the lower end 4404 of the face member 44 and the front end 4802 of the bottom wall 48. The weld bead B2 is formed at a corner where the face back surface 14B and the sole back surface 18B intersect.
In the fifth embodiment as well, as in the fourth embodiment, the leading portion of the face portion 14 enhanced by the weld bead B2 is compared with the rigidity of the upper portion of the face portion 14 enhanced by the weld bead B1. The rigidity closer to the edge 19 is lower, which is advantageous in securing the amount of deflection of the face portion 14 near the leading edge 19 and advantageous in improving the flight distance.
When the head main body 12 excluding the face member 44 is manufactured by casting, the opening 42 exposes the sole rear surface 18B forward, and the front end 4802 of the bottom wall 48 of the sole portion 18 is the front end 1850 of the sole portion 18. Since the core and the lower end 4204 of the opening 42 do not interfere with each other when the core is taken out from the opening 42, the work is facilitated. This is advantageous for improving productivity.

31A and 31B show a comparative example.
In the comparative example, the face portion 14 includes the face member 44 that closes the opening 42.
The lower end of the opening 42 is constituted by the upper end of the wall portion 50 protruding upward from the front end of the sole portion 18.
The wall portion 50 constitutes a lower end 1450 of the face portion 14, and the wall portion 50 constitutes a front end 1850 of the sole portion 18.
In this comparative example, a weld bead B1 at the welded portion between the upper end 4402 of the face member 44 and the upper wall surface 1402 of the face portion 14, and a weld bead B3 at the welded portion between the lower end 4404 of the face member 44 and the upper end of the wall portion 50, Both are formed on the face back surface 14B.
For this reason, the rigidity of the portion near the leading edge 19 of the face portion 14 is increased by the relatively thick weld bead B3, which is disadvantageous in securing the amount of deflection of the face portion 14 near the leading edge 19 and the flying distance. It is disadvantageous for improvement.

Further, in this comparative example, when the core is disposed between the weight portion 38 and the sole back surface 18B in order to manufacture the head body 12 excluding the face member 44 by casting, the following problems occur.
That is, in the comparative example, since the wall portion 50 protruding upward from the front end of the sole portion 18 is provided, the core and the wall portion 50 interfere with each other when the core is taken out from the opening portion 42. Work becomes difficult.
Therefore, the fourth and fifth embodiments are more advantageous than the comparative example in securing the amount of deflection near the leading edge 19 of the face portion 14 and improving the flight distance. This is advantageous for improving productivity by facilitating the child taking-out operation.

  In the fourth and fifth embodiments, the case where the weight portion 38 is formed to protrude from the high-rigidity area 36 toward the face portion 14 has been described. However, the openings 42 and the face member 44 described above are used. Of course, the configuration can be applied regardless of the presence or absence of the weight portion 38.

(Experimental example corresponding to the fourth and fifth embodiments)
Next, experimental examples corresponding to the fourth and fifth embodiments will be described.
In the experimental examples 1 to 36 described above, the configuration of the opening 42 and the face member 44 is the same as that of the comparative example of FIGS. 31 (A) and 31 (B). Therefore, in Experimental Examples 1 to 36, the weld bead B1 at the welded portion between the upper end 4402 of the face member 44 and the upper wall surface 1402 of the face portion 14 and the welded portion between the lower end 4404 of the face member 44 and the upper end of the wall portion 50 are measured. Both the weld bead B3 are formed on the face back surface 14B.
Corresponding to the fourth and fifth embodiments, golf club heads 10 of Experimental Examples 37 and 38 were created, and the same evaluations as those of Experimental Examples 1 to 36 described above were performed.

As a comparative example, Experimental Example 11 corresponding to the second embodiment in which the weight portion 38 protrudes from the high rigidity area 36 toward the face portion 14 is used. Therefore, Experimental Example 11 does not satisfy claims 9-11.
In Experimental Examples 37 and 38, as in Experimental Example 11, the weight portion 38 protrudes from the high-rigidity area 36, and in the same manner as in Experimental Example 11, the provisions of claims 1, 2, 3, 5 to 8 are defined. Further, Experimental Examples 37 and 38 satisfy Claims 9 and 10 or Claims 9 and 11.
Experimental example 37 corresponds to the fourth embodiment (FIGS. 28A and 28B) and satisfies the provisions of claims 9 and 10.
Experimental example 38 corresponds to the fifth embodiment (FIGS. 29A and 29B) and satisfies the provisions of claims 9 and 11.

Experimental example 37 has initial speed 135, flight distance 138, durability 131, and a total of 404. Evaluation of initial speed and flight distance is higher than that of experimental example 11, and durability evaluation is equivalent to experimental example 11. is there.
This is because the amount of deflection near the leading edge 19 of the face portion 14 can be secured, which is advantageous in improving the initial speed and the flight distance.

In Experimental Example 38, the initial speed 136, the flying distance 139, and the durability 131 are 406 in total, and the evaluation of the initial speed and the flying distance is higher than that of Experimental Example 11, and the evaluation of durability is equivalent to that of Experimental Example 11. is there.
This is because the amount of deflection near the leading edge 19 of the face portion 14 can be secured, which is advantageous in improving the initial speed and the flight distance.

Therefore, what satisfies the provisions of claims 1, 2, 3, 5 to 8 within the scope of the present invention, and further satisfies the provisions of claims 9, 10 or 9, 11 is within the scope of the present invention. The effect of improving the initial speed, the flight distance, and the total score is excellent with respect to the outside.
In addition, since the amount of deflection near the leading edge 19 of the face portion 14 can be ensured within the scope of the present invention and satisfying the provisions of the ninth, tenth, or ninth and eleventh aspects, the initial speed, This is advantageous for improving the flight distance.
For example, even if the sole portion 18 is not provided with the weight portions 38 and 40 as in the first embodiment, it is within the scope of the present invention, and the claims 9, 10, or 9. 11 satisfying the requirements of 11 and 11 can secure the deflection amount of the face portion 14 near the leading edge 19 and is advantageous in improving the initial speed and the flight distance.
Further, as in the third embodiment, the weight portion 40 is provided near the face portion 14 of the sole portion 18, and the weight portion 40 includes the first low-rigidity area 32 and the second low-rigidity area. 34, even if it is joined to the portion of the sole portion 18 excluding the high-rigidity area 36, it is within the scope of the present invention and satisfies the provisions of claims 9, 10 or claims 9, 11 Since the amount of deflection of the face portion 14 near the leading edge 19 can be secured, it is advantageous for improving the initial speed and the flight distance.

100 Golf Club 10 Golf Club Head 12 Head Main Body 14 Face Part 1450 Face Lower End 14A Face Face 14B Face Back Face 16 Crown Part 16A Crown Face 18 Sole Part 1850 Sole Part Front End 18A Sole Face 18B Sole Back Face 19 Leading Edge 22 Toe 24 Heel 26 Face back 28 Hollow portion 30 Hosel 32 First low-rigidity portion 34 Second low-rigidity portion 36 High-rigidity portion 38 Weight portion 40 Weight portion 42 Opening portion 44 Face member 4402 Face member upper end 4404 Face member lower end 48 Bottom wall 4802 Front end 50 of bottom wall Wall HP Horizontal plane Pc Center point Pfc of face surface 14A Face center reference section Pf Face reference section Pt First plane Ph Second plane Pb Third plane K1 First boundary point K2 Second boundary point K3 Second Boundary point L1 first reference line L2 second reference line L3 a third reference line

Claims (11)

A face portion constituting a face surface having a vertical height and extending left and right; a crown portion extending rearward from the upper portion of the face portion; and a sole surface extending rearward from the lower portion of the face portion And a head body including a side part extending through a face back between a toe side edge and a heel side edge of the face part between the crown part and the sole part. A golf club head in which the inside surrounded by the face part, the crown part, the sole part and the side part is a hollow part,
In a reference state in which the golf club head is installed at a predetermined lie angle and loft angle with respect to a horizontal plane, the head main body is disposed on a plane that includes a normal passing through a center point of the face surface and is orthogonal to the horizontal plane. The fractured cross section is the face center reference cross section,
A plane parallel to the face center reference section and separated from the face center reference section by 10 mm in the toe direction is defined as a first plane.
A plane parallel to the face center reference cross section and separated from the face center reference cross section by 10 mm in the heel direction is defined as a second plane.
When the plane perpendicular to the face center reference cross section and the horizontal plane and separated from the leading edge by 50 mm in the face back direction is the third plane,
A portion of the sole portion surrounded by the first plane, the second plane, and the third plane has a first low-rigid area, a second low-rigid area, and a high area from the leading edge toward the face-back direction. A rigid area is formed,
The wall thickness d1 of the first low-rigidity area is larger than the wall thickness d2 of the second low-rigidity area, and the wall thickness d3 of the high-rigidity area is equal to or greater than the wall thickness d1 of the first low-rigidity area.
A golf club head characterized by that. In the face reference cross section in which the head body is broken at an arbitrary plane parallel to the face center reference cross section,
A straight line that passes through a first boundary point that is a boundary point between the back surface of the face located on the opposite side of the face surface and the back surface of the sole located on the opposite side of the sole surface is defined as a first reference line L1.
A straight line passing through a second boundary point that is a boundary point between the first low-rigidity area and the second low-rigidity area and perpendicular to the horizontal plane is defined as a second reference line L2.
When a straight line that passes through a third boundary point that is a boundary point between the second low-rigidity area and the high-rigidity area and is orthogonal to the horizontal plane is defined as a third reference line L3,
The first low-rigidity area is at least located in a range from the first reference line L1 to 3 mm in the face-back direction,
The second low-rigidity area is located at least in a range from the second reference line L2 to 3 mm in the face back direction,
The high-rigidity area is located at least in a range from the third reference line L3 to 3 mm in the face back direction,
The weighted average thickness Δd1 of the thickness d1 of the first low rigidity area, the weighted average value Δd2 of the thickness d2 of the second low rigidity area, and the weighted average value Δd3 of the thickness d3 of the high rigidity area Satisfying the following relational expressions (1) and (2),
The golf club head according to claim 1.
0.5 ≦ (Δd2 / Δd1) <1 (1)
1 ≦ (Δd3 / Δd1) (2) A weight part projects from the high rigidity area toward the face part,
The front end of the weight portion is located above the first low rigidity area or above the second low rigidity area,
The weight portion is separated from any of the face portion, the first low rigidity area, and the second low rigidity area.
3. The golf club head according to claim 1, wherein Extending in the toe heel direction and passing through at least one of the upper portion of the first low-rigidity area and the upper portion of the second low-rigidity area, both ends in the extending direction are at least of the sole portion and the side portion. The weight part joined to one side is provided,
The weight portion is separated from any of the face portion, the first low-rigidity area, the second low-rigidity area, and the high-rigidity area.
3. The golf club head according to claim 1, wherein When the head body is viewed in plan in the reference state,
The width in the toe heel direction of the second low rigidity area is 20 mm or more,
The length of the second low-rigidity area along the direction connecting the face portion and the face back is 5 mm or more and 20 mm or less.
The golf club head according to any one of claims 1 to 4, wherein the golf club head is provided. The weighted average value Δd1 of the wall thickness d1 of the first low rigidity area is 1.0 mm or more and 2.0 mm or less,
The weighted average value Δd2 of the wall thickness d2 of the second low rigidity area is 0.5 mm or greater and 1.0 mm or less,
The weighted average value Δd3 of the wall thickness d3 of the high rigidity area is 1.5 mm or more and 10 mm or less.
The golf club head according to claim 1, wherein the golf club head is a golf club head. The thickness d1 of the first low rigidity area is 0.7 mm or more and 2.0 mm or less,
The thickness d2 of the second low-rigidity area is 0.3 mm or more and 1.2 mm or less,
The thickness d3 of the high rigidity area is 1.5 mm or more and 10 mm or less.
The golf club head according to claim 1, wherein the golf club head is a golf club head. The golf club head has a loft angle of 13 ° or more and 30 ° or less,
The volume is 100 cc or more and 200 cc or less,
The center of gravity depth is 10 mm or more and 18 mm or less,
The golf club head according to claim 1, wherein the golf club head is a golf club head. The face portion is provided with an opening that extends from the upper portion to the lower portion of the face portion and exposes the sole rear surface opposite to the sole surface to the front.
The face portion includes a face member that is joined to the opening by welding and closes the opening.
The golf club head according to any one of claims 1 to 8, wherein the golf club head is characterized in that: The upper end of the opening is partitioned by the upper part of the face part,
The lower end of the opening is partitioned by the sole surface at the front end of the sole portion,
The face member is inserted between an upper portion of the face portion and a front end of the sole portion;
The golf club head according to claim 9. The sole portion includes a bottom wall facing the crown portion,
The front end of the bottom wall is located at a location displaced to the face back side from the front end of the sole part,
With the face member joined to the opening by welding and closing the opening, the lower end of the face member constitutes the front end of the sole portion,
The golf club head according to claim 9.

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