JP2007244480A - Golf club - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a golf club which has a head of a simple structure and can reduce the amount of the backspin when a ball is shot as well as increase the carry of the ball. <P>SOLUTION: This golf club has a shaft 5, and the head 7 of a hollow structure which is set and fixed to one end of the shaft 5 at a specified lie angle and a specified loft angle to the reference horizontal plane P. The head 7 has a face section 7a for hitting the ball, and a sole section 7c which touches the reference horizontal plane P. The sole 7c has a groove section 10 which extends in the toe-heel direction, and an upward tilting section 15 which rises from the groove section to the reference horizontal plane P, and is connected with the lower end of the face section. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a golf club, and more particularly, to a golf club having a hollow structure head.

  Conventionally, in a golf club having a hollow structure, various ideas have been applied in order to improve the flight distance. For example, Patent Document 1 discloses that the shearing rigidity, which is parallel to the face surface and the rigidity in the crown / sole direction, is smaller than the vertical rigidity in the direction perpendicular to the face surface, so that the face surface is moved up and down at the time of ball hitting. A hollow structure head that can be greatly bent is disclosed. Specifically, by supporting the striking plate constituting a part of the face surface so as to be displaceable in the crown / sole direction via the joint member, the ball rotates in the direction opposite to the backspin direction when the ball is hit. This makes it possible to suppress the degree of backspin and improve the flight distance.

Further, for example, Patent Document 2 discloses a structure in which an elastically deformable portion that is easily elastically deformed is formed at a portion where a face portion and a sole portion are coupled, with respect to a head having a hollow structure. According to the head having such a structure, the resilience of the hit ball at the lower position of the face portion is improved, so that even if the sweet spot is removed and the hit ball is hit, a decrease in flight distance is suppressed.
JP-A-2005-270321 JP 2004-313762 A

  The head structure disclosed in Patent Document 1 has a problem that the structure of the face portion is complicated and large, and thus increases in weight, so that the degree of freedom in designing the head is reduced. Further, the head structure disclosed in Patent Document 2 described above has a problem that the backspin amount due to the loft angle cannot be sufficiently reduced when the ball is hit, and the flight distance cannot be improved.

  The present invention has been made based on the above-described problems, and an object of the present invention is to provide a golf club that has a simple head structure, can reduce the backspin amount when hitting the ball, and can improve the flight distance. .

  In order to achieve the above object, a golf club according to the present invention has a shaft and a head having a hollow structure that is fixed to one end of the shaft at a specified lie angle and loft angle with respect to a reference horizontal plane. The head includes a face portion for hitting a ball and a sole portion that is grounded to the reference horizontal plane. The sole portion extends from the groove portion to the reference horizontal plane. And an upward inclined portion connected to the lower end of the face portion.

  According to the golf club having the head having the structure as described above, the crossing angle at the connecting portion of the face portion and the sole portion can be increased by providing the upper inclined portion in the sole portion, and at the time of hitting Stress is easily transmitted to the sole portion. The stress generated at the time of striking causes the groove portion provided in the sole portion extending in the toe-heel direction to bend and deform locally, and turn the upper inclined portion upward with the groove portion as a fulcrum. As a result, the face portion can move upward along the face surface, and spin due to face movement acts on the ball at the time of hitting. The spin acting on the ball by this face movement is in a direction to cancel back spin due to the loft angle, thereby reducing the amount of back spin in the direction in which the ball blows up and improving the flight distance.

  As described above, since the face portion can be moved up and down by the shape of the sole portion (upper inclined portion and groove portion), the structure is simple, difficult to weight, and has a high degree of design freedom. Become.

  In order to achieve the above-mentioned object, a golf club according to the present invention includes a shaft, and a hollow structure head fixed to one end of the shaft at a specified lie angle and loft angle with respect to a reference horizontal plane. The head includes a crown portion, a face portion for hitting a ball, and a sole portion that is grounded to the reference horizontal plane, and the crown portion is configured to be able to bend upward when the ball is hit. The sole portion has a fulcrum that allows the face portion to move upward along the face surface when the crown portion curves upward when a ball is hit.

  According to the golf club having the head having the structure as described above, when the ball is hit at the face portion, the face portion moves upward about the fulcrum so as to follow the upward curve of the crown portion. become able to.

  In this way, when the ball is hit, the face portion moves upward, so that the ball at the time of hitting the ball acts as a spin due to the face movement so as to cancel back spin due to the loft angle. The backspin amount in the direction in which the ball blows up can be reduced, and the flight distance can be improved.

  According to the present invention, it is possible to reduce the amount of backspin at the time of hitting with a simple head structure, thereby obtaining a golf club capable of improving the flight distance.

Hereinafter, embodiments of a golf club according to the present invention will be described.
1 to 6 are views showing a golf club according to a first embodiment of the present invention. FIG. 1 is a front view of the golf club, FIG. 2 is a front view of the head, and FIG. 4 is a sectional view taken along line BB in FIG. 3, FIG. 5 is a sectional view taken along line CC in FIG. 3, and FIG. 6 is an enlarged sectional view of the groove shown in FIG.

  The golf club 1 according to the present embodiment has a predetermined lie angle α (intersection angle with the shaft axis X) and a predetermined loft angle β with respect to the reference horizontal plane P at the tip of the shaft 5 made of metal or FRP. The head 7 set at (intersecting angle between the normal to the reference horizontal plane and the face surface) is fixed. In this case, the head 7 includes a face portion 7a for hitting a ball, a crown 7b extending rearward from the upper edge of the face portion 7a, and a sole portion 7c grounded to the reference horizontal plane P. It is formed in a hollow structure including a side portion 7d extending from the toe side edge of the face portion to the heel side edge of the face portion and connecting the edge portions of the crown portion 7b and the sole portion 7c. ing.

  In the drawings, the toe portion, the back portion, and the heel portion constituting such a side portion 7d are indicated by reference numerals 7e, 7f, and 7g, respectively. In addition, the crown 7b and the sole portion 7c may be partially or entirely exposed, or may be separately covered with a cover member attached thereto without being exposed to the outside.

  For the head 7 other than the face material 7a ′ fixed to the face portion 7a (referred to as a head main body 7A), for example, a titanium alloy (Ti-6Al-4V, Ti-15V-3Cr-3Sn-3Al), It is preferable to integrally form iron-based alloy (17-4ph, SUS304), Custum450 (manufactured by Carpenter) or the like, and a face material 7a ′ constituting the hitting surface of the face portion 7a is formed on the front side thereof. A fixed opening 7B is formed. Of course, with respect to the head main body 7A, each member (a face portion, a crown portion, a sole portion, a side portion; an outer shell member) constituting the head main body 7A may be formed individually and fixed by welding, bonding, or the like. good.

  A shaft fastening portion 8 for fastening the tip of the shaft 5 is integrally formed in the head main body 7A. The shaft fixing portion 8 is integrally connected to an opening hole formed on the front end side of the crown portion 7 b and partially protrudes, and the shaft 5 is fixed to the shaft fixing portion 8 formed on the shaft fixing portion 8. It is inserted into the hole 8a and fixed. The shaft fixing portion 8 may be spaced from the crown portion and aligned with the opening hole, or may be connected with a low-rigidity member such as rubber or synthetic resin interposed therebetween.

  For the face material 7a 'fixed to the face portion 7a, for example, titanium alloy (Ti-15V-3Cr-3Sn-3Al, Ti-6Al-4V, SP700, Ti-15V-6Cr-4Al, Ti-15Mo) -5Zr-3Al, iron-based alloy (Custum455,465 (manufactured by Carpenter), 18Ni-12Co-4.5Mo-1.5Ti-Fe), Ti-30Nb-10Ta-5Zr, etc., to have a predetermined plate shape In addition, it is preferable to integrally form by pressing (may be further milled), the face material 7a 'formed in this way is fitted into the opening 7B formed in the face portion 7a, Fastened by adhesion, welding, brazing, or the like.

  The face portion 7a may be integrally formed with the head main body 7A instead of fitting a face material 7a 'as a separate member, or the entire face portion 7a may be a face different from the main body 7A. You may be comprised with the material. In this case, the face portion 7a may be formed in a so-called cup shape in which the periphery thereof is bent to constitute part of the crown portion, the sole portion, and the side portion of the head body.

  In the head 7 configured as described above, the center of gravity position is indicated by the symbol G, and the intersection (sweet spot position) with the perpendicular line extending from the center of gravity position G to the face material 7a ′ is indicated by the symbol S.

  The sole portion 7c has a function of moving (swinging) the face portion 7a (face material 7a ′) in the vertical direction (the arrow direction in FIG. 3) along the face surface. Specifically, the sole portion 7c is formed in a region closer to the face portion than the center of gravity G of the head 7, and the groove portion 10 extends in the toe-heel direction. And an upper inclined portion 15 connected to the lower end of the portion 7a.

  The groove portion 10 is formed inside the sole portion 7c, and has a function of rotating (swinging) the upper inclined portion 15 upward with the groove portion 10 as a fulcrum by the impact when the ball is hit by the face portion. Have. That is, at the time of hitting, the face portion 7a (face material 7a ') has a function of moving upward along the face surface without moving downward, and moving downward after moving upward. For this reason, the groove portion 10 is formed so that the thinned portion is linear (may be dot-shaped) along the toe-heel direction so that the strain is easily concentrated locally. It is preferable. Specifically, as shown in FIG. 6, by forming the groove part in a U-shaped cross section, it becomes easy to bend and deform at the thinnest part (the lowest end position P1 of the groove). The inclined portion 15 is easy to swing in the vertical direction as a whole.

  As described above, the groove portion 10 and the upward inclined portion 15 are formed in the head main body 7A in order to make it easier to move the face portion 7a upward. The main body 7A, the groove portion 10, the upward inclined portion 15 and the like are preferably configured as follows.

  The groove portion 10 is preferably continuously formed along the toe-heel direction on the inner surface side of the sole portion 7c. Further, in the case of such continuous formation, as shown in FIG. 4, the toe portion of the head 7e and the sole portion 7c, and the boundary position P3 between the head heel portion 7g and the sole portion 7c is preferably formed.

  Thus, by forming the groove part 10 continuously and over a wider range, the entire upper inclined part 15 can be easily rotated (moved) upward. Of course, the groove part 10 may be formed partially along the toe-heel direction, or may be formed in a range narrower than the range shown in FIG.

  However, if the length of the groove portion 10 is too short, the upper inclined portion 15 is difficult to rotate with the groove portion 10 as a fulcrum at the time of hitting, so the position where the hit ball is formed, specifically, the sweet of the face portion 7a. It is preferable that the length of the ball including the spot position S is not less than the diameter length range Rs. That is, when the diameter Rs of the ball is viewed in the toe-heel direction, the sweet spot S may be included in the range, and the length of the groove 10 may be equal to or greater than Rs. Thus, by forming the length of the groove portion 10 to include at least the length Rs including the sweet spot S, the face portion 7a can be moved upward during normal hitting.

  The upper inclined portion 15 is formed on the front side of the groove portion 10 in order to facilitate the rotation of the face portion 7a around the groove portion 10 in relation to the loft angle. The inclination angle (inclination angle with respect to the reference horizontal plane P) θ is preferably formed larger than the loft angle β (θ> β). Specifically, the inclination angle θ is set in the range of 8 ° to 30 °, preferably 8 ° to 16 °.

  By making the angle between the two in such a relationship, the crossing angle between the face portion 7a and the upper inclined portion 15 can be 90 ° or more (obtuse angle), and the stress generated at the time of hitting the ball is transmitted to the sole portion so that the groove portion 10 is easily bent and deformed. That is, when the groove portion 10 is bent and deformed, the upper inclined portion 15 is rotated upward about the groove portion 10, and the face portion 7 a can be easily moved upward along the face surface.

  Note that the region where θ> β as described above is preferably formed in the entire region extending in the toe-heel direction shown in FIGS. 4 and 5, but it should be at least in the range Rs.

  As described above, the groove portion 10 has the thin-walled portion P1 that is linear along the toe-heel direction. The thickness of the thin-walled portion P1 is t, and the thickness of the sole portion 7c is the thickness. When T is set (see FIG. 6), it is preferable to form the groove 10 so that t <T / 2. That is, by making the thickness of the thin portion P1 smaller than ½ of the thickness of the sole portion 7c, it becomes possible to concentrate the distortion locally, and the upper inclined portion 15 is made to move upward when hitting a ball. It becomes possible to make it easy to move. However, the thickness t is preferably 0.8 mm or more because the strength is lowered if it is too thin.

  Note that the region where t <T / 2 as described above is preferably formed in the entire region extending in the toe-heel direction shown in FIGS. 4 and 5, but it should be at least in the range Rs. good.

  Further, if the width W of the groove 10 is too narrow, the upper inclined portion 15 cannot sufficiently rotate with P1 as a fulcrum, and if it is too wide, the distortion is dispersed, and the upper inclined portion 15 with the groove 10 as a fulcrum is formed. It becomes difficult to deform. For this reason, it is preferable that the width W of the groove part 10 be 0.5 mm or more and less than the thickness T of the sole part 7c. That is, by making the width W of the groove portion 10 in such a range, the upper inclined portion 15 can be effectively rotated with P1 as a fulcrum, and the upper inclined portion 15 can be easily moved upward at the time of hitting a ball. It becomes possible to do.

  Note that the region where 0.5 mm ≦ W ≦ T as described above is preferably formed in the entire region extending in the toe-heel direction shown in FIGS. 4 and 5, but at least in the range Rs. It ’s fine.

  The length L of the upper inclined portion 15 (defined by the distance between the inflection point at the rising position on the lower surface of the sole portion and the inflection point of the upper inclined portion and the face portion) is the thickness T1 of the portion. In this case, it is preferable to set T1 ≦ L. That is, by setting the length L of the upper inclined portion 15 to T1 or more, the upper inclined portion 15 becomes difficult to follow the deformation in the direction in which the face bends at the time of hitting the ball, and moves upward with P1 as a fulcrum. This can be facilitated. Further, the thickness T1 of the upper inclined portion 15 may be the same as the thickness T of the sole portion 7c as described above, or may be thinner than the sole portion 7c.

  The region satisfying T1 ≦ L as described above is preferably formed in the entire region extending in the toe-heel direction shown in FIGS. 4 and 5, but it is sufficient to have at least the range Rs.

  As shown in FIG. 4, when the sole portion 7 c is curved when viewed from the front, it is preferable to increase R. Thus, the upper inclined portion 15 can be easily moved in the vertical direction by increasing the curved state of the sole portion 7c (increasing R) so as to approach a straight line. Specifically, R is formed to be 200 mm or more, preferably 300 mm or more.

  Further, the sole portion 7c is preferably formed so as to extend in a direction along the reference horizontal plane P as shown in FIG. In this way, by making the linear portion longer along the reference horizontal plane P, it is possible to stably move the upper inclined portion 15 in the vertical direction without changing the sole portion 7c when hitting.

  Further, it is preferable that the crown portion 7b of the head is configured to be easily elastically deformed upward when a ball is hit. That is, when the crown portion 7b is elastically deformed upward, the upward inclined portion 15 follows the movement and is easily rotated upward with P1 as a fulcrum. Specifically, for example, by forming the thickness T3 of the crown portion 7b to be thinner than the thickness T of the sole portion 7c, the crown portion 7b is deformed so that it swells upward at the time of striking and is vertically and horizontally It becomes possible to make the method inclination part 15 follow the movement. Alternatively, the crown portion may be made of a material that is easily elastically deformed, and the crown portion is formed so that the intersection angle between the tangent at the apex P5 of the crown portion 7b and the face portion 7a is 90 ° or more (obtuse angle). Thus, it is possible to easily move the face portion 7a upward at the time of hitting.

  In this case, as shown in FIG. 3, the groove portion 10 is formed so as to be positioned vertically below the boundary portion between the face portion 7a and the crown portion 7b, thereby making it easier to move the face portion 7a upward. Is possible.

  According to the golf club configured as described above, it is possible to reduce the amount of back spin acting on the ball at the time of hitting and improve the flight distance. Hereinafter, this operation will be described with reference to FIGS.

  As shown in FIG. 7, when a ball is hit by the face portion 7a, a component force F3 of a force F1 acting in the horizontal direction that is the traveling direction of the head and a force F2 acting in a direction perpendicular to the face surface that is the ball hitting direction. Acts on the upper side indicated by an arrow along the face surface of the face portion 7a. At this time, since the crown portion 7b is curved and deformed upward, the upper inclined portion 15 can be rotated upward with the thin portion P1 as a fulcrum as shown in FIG. As shown in FIG. 8, the face portion 7a moves upward along the face surface. Then, by the upward movement of the face portion 7a, the spin S2 due to the face movement acts on the ball so as to cancel the back spin S1 due to the loft angle, thereby reducing the back spin amount. As a result, the flight distance can be improved.

  In the above-described embodiment, the face portion 7a is simply fitted and fixed to the opening 7B with the face material 7a 'as in the conventional case. Therefore, the head structure becomes complicated or the entire head becomes heavy. Therefore, the head can be designed with a high degree of freedom in design.

  Actually, as described above, the head (having the upper inclined portion 15 and the groove portion 10) on which the face portion 7a is supported so as to be swingable in the vertical direction is mounted with respect to the golf club (Example) and the reference horizontal plane P. A golf club (Comparative Example 1) equipped with a general hollow structure head configured such that the lower end of the face portion is supported by a parallel extending sole portion and the face portion cannot swing in the vertical direction, and an upward inclination A golf club equipped with a hollow structure head (a hollow structure head having a sole portion which is not formed with a groove and is thinner than the embodiment) in which the lower end of the face portion is supported on the sole portion where the portion is formed For (Comparative Example 2), a trial hit test was performed, and the backspin amount and the flight distance were measured.

  In this trial hit test, the same material (SP700), the same thickness (2.8 mm), and the same loft angle (10.5 °) were fixed to the head body for the face portion of each golf club. The weight of each head was 192 g, and the volume was formed to be about 400 cc. Further, the same shaft (45 inches, Flex R) was used for the shafts to be mounted.

  The test hit test was performed using a robot (a robot testing machine manufactured by Miyamae Co., Ltd.) with a head speed of 40 m / s, a center of the face portion, and a setting that can hit at 1.0 mm from the center of the face portion. When the club was hit with 10 balls and the average value was determined, the test results shown in Table 1 below were obtained. The flight distance was measured by the total flight distance including carry and run.

この試打試験に見られるように、フェース部が上下方向に揺動可能に支持されていることで、ボールの初速度は略同一であるにも拘らず、打球時のバックスピン量を他の比較例のバックスピン量よりも、いずれも低減することが可能となり、これによって、飛距離の向上を図ることができた。

As can be seen in this trial hit test, the face part is supported so as to be swingable in the vertical direction. It was possible to reduce any of the backspin amounts of the examples, and this could improve the flight distance.

  10 and 11 show a second embodiment of the present invention. FIG. 10 is a central sectional view of the head, and FIG. 11 is a sectional view taken along the line DD in FIG.

  In this embodiment, a plurality of ribs 20 extending in the face-back direction are formed at predetermined intervals on the inner surface side of the sole portion 7c. The rib 20 can be formed from the inner surface of the upper inclined portion 15 (the boundary portion between the upper inclined portion and the face portion) to the ridge line E on the back side or the back portion. By forming a large number, it is possible to increase the rigidity of the sole portion 7c, and to prevent the sole from being bent and deformed at the time of hitting.

  Note that the height H of the rib 20 becomes heavy if it becomes too high, and if it becomes too low, sufficient rigidity cannot be obtained, so it is about 50 to 150% with respect to the thickness T ′ of the sole portion 7c. It is preferable to do this. Further, the width W ′ is preferably about 0.5 to 2.0 mm because rigidity is reduced if it is too thin and weight is increased if it is too thick.

  And the groove part 30 is formed in the rib 20 formed in this way so that the effect | action similar to the groove part 10 of above-described embodiment may be exhibited. The groove portion 30 only needs to be configured such that each rib 20 is locally deformed so that the upper inclined portion 15 can rotate upward with the groove portion 30 as a fulcrum. For example, the groove portion 30 extends in the face-back direction. It can be configured by forming a U-shaped notch along the toe-heel direction at the position of the back side end portion of the upper inclined portion 15 of the plurality of existing ribs 20.

  According to such a configuration, the end surface 20a of the rib inside the upper inclined portion 15 and the end surface 20b of the rib formed on the portion along the reference horizontal plane P in the sole portion are in contact with each other at an interval, When the ball is hit, it is deformed locally, and the upper inclined portion 15 can rotate with the groove portion as a fulcrum. Further, in such a configuration, since the sole portion 7c has high rigidity, the upper inclined portion 15 rotates in a stable state, and the face portion 7a can be moved upward.

  FIG. 12 is a diagram illustrating a first modification of the groove formed in the head.

  In each of the above-described embodiments, each of the groove portions 10 and 30 is formed in a U-shaped cross section. However, as shown in the drawing, the groove portion 10a may be formed in a V-shaped cross section. By forming a V-shaped cross section in this way, local deformation is more likely to occur during hitting, and the face portion is likely to move upward.

  FIG. 13 is a diagram showing a second modification of the groove formed in the head.

  In each of the above-described embodiments, each of the groove portions 10 and 30 is formed at one location along the toe / heel direction, but may be formed at a plurality of locations (three locations in the modification) as shown in the figure. By forming a plurality of locations in this way, the upper inclined portion 15 can be rotated more greatly upward when hitting, and the face portion can be easily moved upward.

  As described above, the embodiment of the present invention has been described. However, the present invention only requires that the sole portion of the head has a support structure that can swing the face portion in the vertical direction along the face surface. Various modifications can be made to the overall shape, material, formation method, and the like. That is, the present invention has a structure in which the upper inclined portion 15 rising toward the lower end of the face portion is provided on the sole portion, and a fulcrum that allows the upper inclined portion to turn upward is provided. If present, the overall shape, the thickness of each part, the material, and the like can be appropriately modified.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows 1st Embodiment of the golf club which concerns on this invention, and is a front view of a golf club. The front view of a head. Sectional drawing along the AA line of FIG. 2 (sectional drawing in a gravity center position). Sectional drawing along the BB line of FIG. Sectional drawing along CC line of FIG. The expanded sectional view of the groove part shown in FIG. The figure explaining the effect | action of the face part of a head at the time of a hit ball. The figure which shows the state of the spin which acts on a ball | bowl at the time of a hit ball. The enlarged view which shows the state which a face part moves upwards by using a groove part as a fulcrum at the time of hitting. The center sectional view of the head showing the 2nd embodiment of the present invention. FIG. 11 is a cross-sectional view taken along line DD in FIG. 10. The figure which shows the 1st modification of the groove part formed in a head. The figure which shows the 2nd modification of the groove part formed in a head.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Golf club 5 Shaft 7 Head 7A Head main body 7a Face part 7b Crown part 7c Sole part 10, 10a, 30 Groove part 15 Upper inclination part 20 Rib G Center of gravity P Reference | standard horizontal surface S Sweet spot

Claims (10)

A shaft, and a hollow structure head that is fixed at a predetermined lie angle and loft angle with respect to a reference horizontal plane at one end of the shaft, the head including a face portion for hitting a ball, and the reference horizontal plane A golf club having a sole portion that is grounded to
2. The golf club according to claim 1, wherein the sole portion includes a groove portion extending in a toe-heel direction, and an upward inclined portion that rises from the groove portion with respect to a reference horizontal plane and is connected to the lower end of the face portion.   2. The golf club according to claim 1, wherein the groove portion has a length that is at least a diameter length range Rs of a ball including at least a sweet spot position of the face portion.   3. The golf club according to claim 2, wherein the groove portion is formed beyond a boundary between a toe portion and a sole portion of a head and a boundary between a heel portion and a sole portion of the head.   The groove portion has a thin-walled portion that is linear along the toe-heel direction. When the thickness of the thin-walled portion is t and the thickness of the sole portion is T, t <T / 4. The golf club according to claim 1, wherein an area to be 2 is at least in the range Rs. 5.   5. The golf club according to claim 1, wherein when the width of the groove portion is W, a region satisfying 0.5 mm ≦ W ≦ T is included in at least the range Rs.   6. The device according to claim 1, wherein when the length of the upper inclined portion is L and the thickness thereof is T <b> 1, a region satisfying T <b> 1 ≦ L is included in at least the range Rs. Golf club.   7. The golf club according to claim 1, wherein an inclination angle of the upward inclined portion with respect to the reference horizontal plane is larger than a loft angle at least in the range Rs.   The golf club according to claim 1, wherein the crown portion of the head is formed to be thinner than the sole portion. The sole part is formed with a plurality of ribs extending in the face-back direction,
9. The golf club according to claim 1, wherein the groove portion is formed in a rib at an end portion position of the upward inclined portion. A shaft, and a hollow structure head fixed at a predetermined lie angle and loft angle with respect to a reference horizontal plane at one end of the shaft, the head including a crown portion and a face portion for hitting a ball A golf club comprising a sole portion that is grounded to the reference horizontal plane,
The crown portion is configured to be able to bend upward when the ball is hit, and the sole portion is configured so that the face portion is raised upward along the face surface when the crown portion is bent upward when the ball is hit. A golf club having a fulcrum that allows movement.

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