Golf club

Abstract

To provide a golf club which can obtain a hands-ahead-of-the-ball state in the address and exerts an image assisting function of a desired trajectory of a club head.SOLUTION: A golf club includes a curved part 15 of a club shaft for varying a grip part 14A in a target direction F of a club head 12 in addressing a club face perpendicularly to the target direction (a direction of a target line) F. The curved part 15 curves from an upper end of a linear part 11A of a club shaft 11 extending from the club head 12 in the target direction F and inclines the grip part 14A so that the grip part 14 toward to the upper end is in the target direction F. The curved part 15 is provided within a range of 10 cm or less from a lower end 14A of the grip part 14A.SELECTED DRAWING: Figure 1

Description

【Technical Field】 【0001】 The present invention relates to a golf club Bu and particularly to a golf club for practice. 【Background Art】 【0002】 Conventionally, a golf club having a bent portion of a club shaft that displaces a grip portion in the target direction of a club face when the club face is addressed perpendicular to the target direction is known. For example, Patent Document 1 discloses a practice iron golf club in which a portion approximately in the center in the longitudinal direction of the club shaft is bent. According to this, it is said that a hand-first state can be obtained when gripping the grip portion. Further, Patent Document 2 discloses a putter golf club in which two portions are bent, one at a position from the head and approximately at the center in the longitudinal direction, the portion from the head to approximately the center is inclined in the target direction, and the portion from approximately the center to the grip portion extends vertically upward. According to this, a hand-first state can be obtained, and it is said that it is easy to grasp the directionality and distance sense of putting. 【Summary of the Invention】 <00,00015>【Problems to be Solved by the Invention】 【0003】 As shown in the left diagram of Figure 1, a normal shaft that is straight throughout has a virtual extension line extending from the top of the grip that points approximately to the center of the golfer's body, and this virtual extension line helps the golfer visualize the circular trajectory of the club head around the center of the body. However, in the golf club of Patent Document 1, as shown in the left and right center diagrams of Figure 1, the virtual extension line from the top of the straight section from the head to approximately the center of the longitudinal direction of the club shaft may point towards the center of the body, but this straight section is about half the length of a normal shaft. Moreover, the length from the bent section to the grip section is also half the length of the entire shaft, so a golfer holding the grip section may also visualize the virtual extension line of the straight section from the grip section to the bent section. As a result, the function of the straight section of the club shaft extending from the club head assisting in visualizing the circular trajectory of the club head is reduced to less than half. 【0004】 Even with the putter golf club described in Patent Document 2, the image assistance function described above can hardly be expected. While a normal shaft that is straight as a whole can provide an image assistance function regarding the trajectory of the club head (a nearly straight trajectory before and after impact), the putter golf club in Patent Document 2 has two predetermined bends, so there is no straight section connecting the head and the center of the body. 【0005】 This invention has been made in view of the above problems, and its objective is to provide a golf club that allows the golfer to achieve a hand-first position at address and also provides an image assistance function for the desired trajectory of the club head. [Means for solving the problem] 【0006】 To solve the above-mentioned problems, the present invention provides a golf club having a bent portion of the club shaft that displaces the grip portion in the target direction of the club face when the club face is addressed perpendicular to the target direction, wherein the bent portion is bent from the upper end of the straight portion of the club shaft extending from the club head toward the target direction, inclining the grip portion so that the upper end of the grip portion is toward the target direction, and is provided within a range of 10 cm from the lower end of the grip portion. [Effects of the Invention] 【0007】 According to the present invention, a predetermined bend is provided within 10 cm of the lower end of the grip, allowing the straight section from the club head to the predetermined bend to be of sufficient length. Therefore, a hand-first position can be achieved during the swing, and it can also provide an image-assistance function for the desired trajectory of the club head. [Brief explanation of the drawing] 【0008】 [Figure 1] An explanatory diagram comparing the golf club according to the present invention with a conventional example. [Figure 2] Diagram illustrating a golf club according to the first embodiment. [Figure 3] An explanatory diagram of an example of a method for manufacturing a golf club according to this embodiment. [Figure 4] An explanatory diagram of a modified example. [Figure 5] An explanatory diagram of a golf club according to the second embodiment. [Figure 6] An explanatory diagram of a modified example of the second embodiment. [Figure 7] An explanatory diagram of the impact of a golf club according to the second embodiment. [Modes for carrying out the invention] 【0009】 Embodiments of the present invention will be described below with reference to the drawings. The right-hand diagram of Figure 1 is an explanatory diagram of a practice golf club (hereinafter simply referred to as a golf club) according to this embodiment. In the figure, the so-called iron-type golf club 10 consists of a club shaft 11, a club head 12 attached to one end (tip) of the club shaft 11, and a grip portion 14A to which a grip member 14 is attached to the other end (base) of the club shaft 11. The club head 12 is made of metal and has a hosel portion 13 integrally attached. The club shaft 11 is fixed so as to extend into the hosel portion 13. The club shaft 11 may be formed of hollow cylindrical steel, or it may be formed using carbon as the molding material. 【0010】 Furthermore, the golf club 10 of this embodiment has a bent portion 15 of the club shaft that displaces the grip portion 14A toward the target direction F of the club face when the club face is addressed perpendicular to the target direction (flight line direction) F. The bent portion 15 bends from the upper end of the straight portion 11A of the club shaft 11 extending from the club head 12 toward the target direction F, and inclins the grip portion 14A so that the rear end 14B, which is the upper end of the grip portion 14A, is toward the target direction F. This bent portion 15 is provided within a range of 10 cm from the tip 14C, which is the lower end of the grip portion 14A. 【0011】 [First Embodiment] Figure 2 is an explanatory diagram of a golf club 10 according to the first embodiment. Figure 2(a) is an explanatory diagram viewed from a direction perpendicular to a virtual plane (PL1) that includes the axis L1 of the straight section 11A of the club shaft 11 and the axis L2 of the grip section 14A. Figure 2(b) is an explanatory diagram viewed from the grip section 14A side, in a direction parallel to the axis L1 of the straight section 11A in Figure 2(a). Figure 2(c) is an explanatory diagram of a golf club 10 in an address position where the face of the club head 12 is perpendicular to the target direction (flight line direction) F, viewed from the opposite side of the target direction F (target side), and the lie angle θ2 is also shown. Figure 2(d) is an explanatory diagram of the golf club 10 in the state of Figure 2(c) viewed from vertically above. Only the feet and hips of golfer P are schematically shown. 【0012】 Hereinafter, the state in which the club head 12 is positioned perpendicular to the target direction (flight line direction) F is referred to as the square address state. The virtual plane containing the axis L1 of the straight section 11A of the club shaft 11 and the axis L2 of the grip section 14A is called the shaft-grip plane PL1. The virtual plane containing the target direction F and perpendicular to the ground is tilted by a lie angle θ2 and is called the lie angle plane PL2. In the square address state, the axis L1 of the straight section 11a of the golf club lies on the lie angle plane PL2. 【0013】 The club head shown in Figure 2 is one in which, when the golf club head is set with the sole parallel to the ground and the shaft's centerline (axis) is on a plane perpendicular to the ground, the club head's face angle, which is the angle between a horizontal line parallel to the face (usually the leading edge) and the vertical plane, is 0°. The face angle is determined by the position and angle relationship between the club head's face and sole and the axis of the shaft insertion hole in the hosel, which determines the inclination of the shaft axis. 【0014】 As shown in Figure 2(a), the club head 12 with a face angle of 0° is mounted on the club shaft 11 such that the face faces toward the rear end 14B of the grip portion 14A which is bent at the bent portion 15, and as shown in Figure 2(b), the leading edge 12a is perpendicular to the shaft-grip plane PL1. 【0015】 The distance L3 between the tip 14C of the grip portion 14A and the bent portion 15 in Figure 2(a) is set to be within a range of 10 cm or less. Preferably, it is set to be within a range of 5 cm or less, and more preferably within a range of 2 cm or less. The bending angle θ1 of the grip portion 14A in Figure 2(a) is within a range of 1° to 60°, preferably within a range of 30° to 50°, and more preferably within a range of 40° to 50°. In the illustrated example, the distance L3 is 1 cm and the bending angle θ1 is 45°. 【0016】 In the golf club where the club head 12 is attached to the club shaft 11 as described above, as shown in Fig. 2(a), on the shaft-grip plane PL1, the linear leading edge 12a of the club head 12 with a face angle of 0° is parallel to the axis L1 of the straight portion 11A of the club shaft 11. Also, as shown in Fig. 2(c), in the square address state, the shaft-grip plane PL1 overlaps the lie angle plane PL2, and the axis L2 of the grip portion 14A is also located on the lie angle plane PL2. Note that the apparent angle θ3 between the axis L1 of the straight portion 11a and the axis L2 of the grip portion 14A in Fig. 2(d) is caused by the influence of the lie angle θ2 and is smaller than the angle θ1. 【0017】 What the reference numeral 16 indicates in Fig. 2(b) is an example of a mark when a golfer grips the grip member 14. In the case of this example, after gripping so that the mark 16 faces vertically upward, as shown in the right figure of Fig. 1, if the golfer is right-handed, the left hand is pronated and the right hand is supinated so that the club head 12 faces the target direction F. 【0018】 The clock face 51 attached to the left arm of the golfer P in the right figure of Fig. 1 faces the front side of the golfer P, unlike the clock face 51 attached to the left arm of the golfer P in the left figure and the left-right center figure that faces the target direction F. This is an example where the bending angle θ1 shown in Fig. 2 is 45 degrees. In this state, flapping of the grip toward the target direction F is substantially suppressed. This is because the direction of the wrists when moving the entire grip in the target direction is different from the direction that causes flapping of the golf club with respect to the wrists due to the inertia of the golf club. Also, if an attempt is made to consciously perform flapping, the behavior of the club head 12 will become completely unnatural behavior different from the target. 【0019】 In addition, since it would lead to unnatural behavior of the club head 12, attempting to perform the so-called wrist turn motion before and after impact is also suppressed. Even in the golf club 40 shown in the middle right figure of FIG. 2, which is somewhat hands-forward, there is a slight pronation of the left hand and supination of the right hand, but it is insufficient to suppress the flapping or wrist turn motion of the grip. To effectively prevent the above flapping, etc., the bending angle θ1 is set within the range of 30° to 50°, more preferably within the range of 40° to 50°. 【0020】 When set within such a range, as a result of suppressing the above flapping, etc., the takeback can be started without disrupting the three-dimensional pentagon formed by both shoulders, the left arm, the left and right grips, the right elbow approaching the right flank from the right wrist of the right hand, and from the right elbow to the right shoulder (since the right elbow approaches the flank, the right elbow deviates downward from the plane including other parts to form a three-dimensional shape). Up to about a half swing, it is possible to cut and follow through as it is. It is optimal for approach using irons from a sand wedge to about an 8-iron. In such an approach, it is an image of consciously pushing in the target direction of the right hand and pushing the head straight in the target direction from impact to follow through. 【0021】 Furthermore, when set within such a range, it is also effective in suppressing an overswing that causes the shaft to cross when taking back beyond the top of the half swing. As shown in FIG. 2(d), since the club center of gravity G near the club head 12 is located on the fly ball line (F) side rather than on the extension line of the axis L2 of the grip portion 14A shown by the two-dot chain line toward the head side, a rotational moment due to the club center of gravity X around the axis L2 related to both hands acts with sufficient magnitude. This is because if the top position is suppressed within the range where the grip force by both hands that antagonizes this rotational moment is continuously applied, an overswing will not occur. 【0022】 As described above, this club enables a hand-first swing not only in approaches and half swings, but also in full swings. It is ideal as a golf club for practicing this type of swing, and can be used on actual golf courses when permitted by golf regulations. 【0023】 Figure 3 shows an example of a manufacturing method for the golf club 10 of this embodiment. Figure 3(a) is an exploded view, and Figure 3(b) is an enlarged cross-sectional view of the vicinity of the bent portion. In this example of manufacturing method, a golf club kit is assembled that includes at least a club shaft part 11B which is equipped with a club head 12 at the tip or which can be attached, a grip part part 14D, and a connecting member 20 which connects the club shaft part 11B and the grip part part 14D. As shown in Figure 3(b), the connecting member 20 has a bent portion 15 located within 10 cm from the tip of the grip part 14A when the club shaft part 11B and the grip part part 14D are connected. The tip of the grip part 14A is the tip 14C of the grip member 14, and the position of the bent portion 15 is the position of the bending start point R0 of the bent portion 15 which is close to the tip 14C. 【0024】 The example in Figure 3(b) shows a club shaft made of a normal hollow metal shaft, cut at the tip 14C of the grip member 14 to form a club shaft component 11B and a grip component 14D. The grip component 14D has the grip member 14 attached to the metal shaft portion 11C. The connecting member 20 is made of, for example, an aluminum rod with a circular cross-section. When the club shaft is cut at the tip 14C of the grip member 14 of a metal shaft club shaft, the diameter of the aluminum rod that can be inserted into the hollow part of the metal shaft at this cut point is about 13 mm. Even with aluminum shafts with a relatively small hollow diameter, such as those for children or women, an aluminum rod of about 12 mm can be used. The club shaft does not have to be hollow metal; it may also be made of a hollow carbon molding material (glass fiber). In any case, the connecting member 20 is not limited to metal such as aluminum, but can be made of a material with sufficient strength such as glass fiber or plastic. 【0025】 Each end of the connecting member 20 is inserted, for example, about 7 cm into the hollow section of the club shaft part 10A and the grip part (14), and then bonded with adhesive. The adhesive used to bond the shaft by inserting it about 5 cm into the hosel part 13 of the club head can be used. As shown in Figure 3(b), the insertion parts at each end may be screwed in with screws 21. In addition to screws, fasteners such as bolts can also be used. 【0026】 In Figure 3(b), a portion L6 of the connecting member 20 is secured that is not inserted into the club shaft component 11B beyond the bent portion 15. This portion is for creating the same height position at the grip portion 14A as the part of a normal golf club grip that is held with both hands, as shown by the two-dot line on the axis L1 in Figure 2(a). When the club shaft is cut at the tip 14C of the grip member 14 of an iron golf club pitching to form the club shaft component 11B and the grip portion component 14D, and the bending angle of the connecting member 20 is set to 45°, a suitable example is that L3 is 1 cm and L4, L5, and L6 are 7 cm in Figure 3(b). 【0027】 The parts shown in Figure 3(a) can also be made into a golf club kit by adding adhesive and / or fasteners such as screws 21 or bolts. Furthermore, a golf club shaft with a grip can be sold, where a bent section that curves from the rear end of the straight section to which the club head is attached to the tip, creating an inclined grip section, is provided within 10 cm of the tip of the grip section. Because a normal hollow shaft is cut at the tip of the grip, the shaft on the club head side can exhibit the same deflection as a normal club shaft. 【0028】 Figure 4 is an explanatory diagram of a modified example. Figure 4(a) shows another example of the manufacturing method of the golf club 10 of this embodiment. In this example, a core member 22 is inserted into a hollow club shaft 11 and then bent. The bending process is carried out while heating as needed. The core member is made of a material suitable for such bending. A fixing process may be performed before or after the bending process to fix the position of the core member. 【0029】 Figure 4(b) illustrates an example using a mechanism that allows the bending angle θ1 to be changed (adjusted). Figure 4(b) shows the connecting member 20 of Figure 3(a) configured as follows: It comprises insertion parts 20A and 20B that are inserted into the hollow parts of the club shaft part 11B and the grip part 14D, respectively, and a mechanism 23 that connects these insertion parts in a way that allows the angle to be changed. This mechanism 23 also includes an angle fixing operation part 23A for fixing the angle after the change by tightening or the like. Various known mechanisms can be used for this type of angle-adjustable connecting mechanism 23. 【0030】 [Second Embodiment] Figure 5 is an explanatory diagram of the golf club 10 according to the second embodiment. In the golf club of the second embodiment, as shown in Figure 5(c), which corresponds to Figure 2(c), the mounting angle of the club head 12 with respect to the club shaft 11 is set such that when the club head 12 is addressed perpendicular to the target direction A, the grip portion 14A is located closer to the golfer P than a virtual plane (PL2) that includes the straight portion 11A of the club shaft and is parallel to the target direction. 【0031】 Figure 5(a) corresponds to Figure 2(d). The golfer addresses the ball in an open stance so that the hips are turned to the left at impact. This is an address sometimes used in approach shots. The golf club 10 of this embodiment 2 is suitable for practicing an address or impact position where the hips are open relative to the target direction F and the hands are ahead. 【0032】 Using a shaft with the bending angle θ1 shown in Figure 2(a), in order to make the distance between the left and right grips and the hips the same as in Figure 2(d) while the hips are open in this way, it is necessary to make the angle θ3 between the straight section 11A and the grip section 14A smaller than the angle θ3 in Figure 2(d), as shown in Figure 5(a). The angle θ3 can be made smaller by rotating the straight section 11A counterclockwise around its axis L1. However, when rotated in this way, the club head 12 also rotates counterclockwise, as shown by the dashed line in Figure 5(a), causing the leading edge 12A to point to the left of the target direction F. 【0033】 Therefore, in the second embodiment, as shown in Figure 5(b), which corresponds to Figure 2(b), the leading edge 12a of the golf club is attached to the club shaft 11 in such an open manner that it is tilted by an angle θ4 upstream of the target direction F from the angular direction perpendicular to the shaft-grip plane PL1. This angle θ4 is set according to the angle at which the hips are opened. For example, when the hips are opened 45°, θ4 is also set to about 45°. 【0034】 In a golf club with the club head 12 mounted at an angle θ4, as shown in Figure 5(c), which corresponds to Figure 2(c), the grip portion 14A in a square address position is located closer to the golfer than the lie angle plane PL2. For golf clubs where the bending angle θ1 of the axis L2 of the grip portion 14A relative to the axis L1 of the straight portion 11A of the club shaft 11 shown in Figure 2(a) is in the range of 30° to 45°, this is particularly suitable for practicing swings where the hips are open at address or impact. 【0035】 Figure 6 shows a modified example of the second embodiment. This modified example includes a mechanism that allows the mounting angle position of the club head 12 relative to the straight section 11A of the club shaft 11 to be changed. Figure 5 shows an example of such a mechanism, in which a rotation angle restricting section 30A and a fastening section 30B are integrally formed on the tip side of a socket 33 that is integrated with the club shaft 11 and inserted into a hole in the hosel section 13 of the club head 12. A rotation restricting section 31A that engages with the rotation angle restricting section 30A to restrict the rotation position is formed in the insertion hole of the hosel section 13, and a nut insertion section 31B for screwing into the fastening section 30B is formed at a deeper location. The mounting angle position of the club head 12 can be changed by loosening the nut 32, removing the shaft, changing the rotation position, and reinserting it. 【0036】 This example is not the only one that can be used; various face angle adjustment mechanisms can be employed. Furthermore, a golf club shaft with a grip that is detachable from this type of club head 12 is suitable for sale as a golf club shaft with a grip, in which the bent section that curves from the rear end of the straight section to which the club head is attached to the tip, and inclins the grip section, is provided within 10 cm from the tip of the grip section. 【0037】 Figure 7 is an explanatory diagram of the moment just before impact in a full swing using the golf club 10 of the second embodiment, with the hips open at approximately 45°. Based on the impact illustrations introduced in Ben Hogan's Modern Golf, this is a perspective view showing the impact when using the golf club 10 of the second embodiment, with a bending angle of 45° and θ4 of 45° in Figure 5(b). In a square stance, the hips are open at 45° at impact, but the shoulders are not as open as the hips. The head maintains its address position while the hips move towards the target, and almost all of the weight is on the left foot. For practicing such a full swing with open hips and a hand-first impact, a golf club with θ1 in the range of 30° to 50°, more preferably 40° to 50°, and θ4 in the range of 30° to 50°, more preferably 40° to 50°, is preferable. 【0038】 In the above description, the golf clubs shown in the drawings are for right-handed golfers, but they can also be applied to left-handed golfers. Furthermore, although the illustrated golf clubs are iron golf clubs, they can also be applied to putter golf clubs and wood golf clubs. For putter golf clubs, it is preferable to mount the club head 12 so that the leading edge of the club face is perpendicular to the shaft-grip plane PL1, as in the golf club of the first embodiment. Various modifications are possible, such as changes to the material and specific shape, as long as they do not deviate from the intended purpose. [Explanation of Symbols] 【0039】 10: Golf Club 10A: Club shaft parts 11: Club shaft 11A: Straight section 11B: Club shaft parts 11C: Metal shaft part 11a: Straight section 12: Club Head 12A: Leading Edge 12a: Leading edge 13: Hosel section 14: Grip component 14A: Grip section 14B: Rear end 14C: Tip 14D: Grip part 15: Bent section 16: Landmark 20: Connecting member 20A: Insertion part 20B: Insertion part 21: Screw 22: Core member 23:Mechanism 23A: Angle fixed operation part 30A: Rotation angle regulating section 30B: Fastening part 31A: Rotation restricting section 31B: Insertion part 32: Nut 33: Socket 40: Golf Club 51: Watch dial A: Target direction F :Target direction G: Club center of gravity L1: Axis line L2: Axis line L3: Distance L6: Length portion not to be inserted P: Golfer PL1: Grip flat PL2: Lie plane R0: Bending start point X: Club center of gravity θ1: Bending angle θ2: Lie angle θ3: Angle θ4: Angle [Prior art documents] [Patent Documents] 【0040】 [Patent Document 1] Japanese Patent Publication No. 2019-136448 [Patent Document 2] Japanese Patent Publication No. 2012-16555

Claims

[Claim 1] A golf club having a bent section in the club shaft that displaces the grip section in the direction of the target of the club face when the club face is addressed perpendicular to the target direction, The aforementioned bent portion is a golf club characterized in that it bends from the upper end of the straight portion of the club shaft extending from the club head toward the target direction, causing the grip portion to be inclined so that the upper end of the grip portion is toward the target direction, and is provided within a range of 10 cm from the lower end of the grip portion. [Claim 2] The golf club according to claim 1, characterized in that the bending angle of the bent portion is set within the range of 1° to 60°. [Claim 3] The golf club according to claim 1, characterized in that the bending angle of the bent portion is within the range of 30° to 50°. [Claim 4] The golf club according to any one of claims 1 to 3, characterized in that when the golfer addresses the club with the club face perpendicular to the target direction, the grip portion is positioned closer to the golfer than a virtual plane parallel to the target direction that includes the axis of the straight portion of the club shaft. [Claim 5] The golf club according to claim 4, wherein the mounting angle is set such that, when viewed from a direction parallel to the axis of the straight portion of the club shaft, the leading edge of the club face is open within the range of 30° to 50° with respect to an angular direction perpendicular to a virtual plane containing the axis of the grip portion and the axis of the straight portion. [Claim 6] The golf club according to claim 4, further characterized by having a mechanism that allows the mounting angle of the club face to be changed. [Claim 7] The golf club according to any one of claims 1 to 3, characterized in that it is provided with a mechanism that can change the bending angle of the bent portion.

Images