JP2016163625A - Golf club - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a golf club further facilitating suppressing change in a carry by the vertical deviation of a hitting point.SOLUTION: A golf club 1 includes a shaft 20, and a head 10 provided at the tip side of the shaft 20. The golf club 1 makes a rotational motion around an axis AH in which an impact transmittance range to which an impact force received from a ball during an impact period when the head 10 and the ball contact when hitting the ball with the head 10 is transmitted passes a center of gravity of an impact transmittance range part of the golf club, and which is in parallel to both ground surface and face. In the golf club 1, a first weight article WB is provided in a position lower than the axis AH in the impact transmittance range, and a second weight article WT is provided in a position higher than the axis AH so as to enlarge a moment of inertia around the axis AH by the impact transmittance range part of the golf club and suppress change in a carry by the vertical deviation of a hitting point.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a golf club, and more particularly to a golf club in which it is easier to suppress a change in flight distance due to vertical displacement of a hitting point.

  Various improvements have been made to golf clubs to obtain better scores in golf competitions. For example, in Patent Document 1, in the case of a mis-hit shifted in the vertical direction of the sweet spot, the shaft bends and the direction of the face changes, so that the trajectory of the golf ball becomes low or high and the flight distance decreases. Focusing attention, a golf club that can prevent a change in the orientation of the face and secure a flight distance is disclosed. Specifically, in a golf club in which the shaft is inserted and fixed to the base of the head, the bending rigidity within a predetermined range from the inside of the base of the shaft to the grip direction is reinforced, and the weight is near the end of the reinforced region. By providing a body, changes in the face direction are prevented.

JP 09-262325 A

  However, in the golf club shown in Patent Document 1, it is difficult to sufficiently suppress the change in the flight distance due to the shift of the hit point because the movement of the entire head and the reinforcing region is not suppressed from being changed due to the shift of the hit point. It is. Further, in the golf club of Patent Document 1, since the reinforcement region is provided, the weight of the entire shaft increases, and the golf club itself becomes difficult to swing, and further, stress concentrates on the end of the reinforcement region, The shaft may be broken.

  The present invention has been made to solve the above-described conventional problems, and an object of the present invention is to provide a golf club in which it is easier to suppress a change in a flight distance due to a vertical shift of a hitting point.

  In order to achieve at least a part of the above-described problems, a golf club of the present invention is a golf club having a shaft and a head provided on the tip end side of the shaft when the ball is hit with the head. A first heavy object and a second heavy object are provided in an impact transmission range in which an impact force received from the ball during an impact period in which the head and the ball are in contact with each other, The first weight is disposed at a position lower than an axis that passes through the center of gravity of the portion of the impact transmission range of the golf club and is parallel to both the ground surface and the face surface of the head. The object is arranged at a position higher than the axis.

  In general, the trajectory of the ball after hitting is affected not only by the behavior of the head during the impact period but also by the behavior of the entire impact transmission range in which the impact force received from the ball during the impact period is transmitted. According to this configuration, by providing a heavy object at each of a position lower than and higher than the axis passing through the center of gravity of the portion of the impact transmission range of the golf club, rotation of the golf club about the axis is performed. The moment of inertia (effective longitudinal moment of inertia) due to the portion of the impact transmission range increases. Therefore, the change in the behavior of the impact transmission range during the impact period due to the hit point shifting up and down is suppressed, and the change in the flight distance of the ball due to the hit point shifting up and down can be suppressed.

  The first heavy article may be arranged in the vicinity of the shaft axis. By providing the first heavy object in the vicinity of the shaft axis, an increase in the moment of inertia around the shaft axis can be suppressed. Therefore, it is possible to suppress a change in the flight distance of the ball due to the hit point shifting up and down while maintaining a good return of the head when swinging the golf club.

  Note that the present invention can be realized in various modes. For example, it is realized in various modes such as a golf club, a head and a shaft constituting the golf club, a fixing means for fixing the head and the shaft, a golf club adjusting method, and a member used in the adjusting method. It may be a thing.

Explanatory drawing which shows the structure of the fixed part vicinity of the head and shaft in a golf club. Explanatory drawing explaining the function of the two weights which a golf club has. Explanatory drawing explaining the function of the two weights which a golf club has.

  FIG. 1 is an explanatory diagram showing a configuration in the vicinity of a fixed portion between a head 10 and a shaft 20 in a golf club 1 as an embodiment of the present invention. In the example of FIG. 1, a golf club called a driver is shown as the golf club 1, but the present invention is not limited to a driver, a wood-type golf club such as a so-called fairway wood, a golf club called a utility, or The present invention can also be applied to iron-based golf clubs. As shown in FIG. 1, the head 10 and the shaft 20 of the golf club 1 are fixed using a sleeve 30 and a fixing bolt 40. In the following, among the directions along the center axis (shaft axis) AS of the shaft 20 indicated by the alternate long and short dash line, the side in the direction from the shaft 20 toward the head 10 is referred to as the tip side, and the direction from the head 10 toward the shaft 20 This side is called the rear end side.

  The head 10 has a hollow structure in which a face 11, a crown 12, a sole 13, a heel 14, a toe 15, and a hosel 16 are integrally formed of a titanium alloy or the like. The cylindrical hosel 16 penetrates the inside of the head 10 from the crown 12 toward the sole 13 on the heel 14 side. The hosel 16 has a narrowed portion 161 having a narrow inner diameter between the crown 12 side and the sole 13 side. The shaft 20 is formed, for example, by winding an uncured sheet (prepreg) of carbon fiber reinforced resin (CFRP) around a core metal and then heating to cure the prepreg.

  The sleeve 30 is provided with a bottomed cylindrical sleeve body 31, a rear end side of the sleeve body 31, a cylindrical sleeve large diameter portion 32 having a large outer diameter, and a distal end side of the sleeve body 31. And a female thread portion 33 having a small diameter and having a female thread in the direction of the shaft axis AS. The inner surface of the bottomed cylindrical sleeve body 31 and the inner surface of the cylindrical sleeve large diameter portion 32 form a shaft insertion hole 39 into which the shaft 20 is fitted.

  The fixing bolt 40 has a bolt shaft portion 41 formed with a male screw that meshes with the female screw portion 33 of the sleeve 30, and a bolt head portion 42 provided on the distal end side of the bolt shaft portion 41. A tool engagement hole 49 for inserting a tool and rotating the fixing bolt 40 is formed on the tip side of the bolt head 42. In this embodiment, the bolt head 42 is made to function as a weight (heavy object) by extending the bolt head 42 of the fixing bolt 40 in the shaft axis AS direction. The bolt head 42 is passed through a hole (bore) in the center of the hosel 16 that penetrates the head 10 and functions as a weight. Therefore, the bolt head 42 can also be referred to as a bore through weight WB.

  As shown in FIG. 1, the shaft 20 is fixed to the sleeve 30 by fitting the distal end portion of the shaft 20 into the shaft insertion hole 39 of the sleeve 30. The sleeve 30 into which the shaft 20 is fitted is inserted into the hosel 16 from the rear end side of the hosel 16. As described above, when the male screw formed on the bolt shaft portion 41 is screwed into the female screw formed on the female screw portion 33 from the distal end side in a state where the sleeve 30 is inserted into the hosel 16, the surface on the distal end side of the sleeve main body 31 is obtained. The (front end surface) and the rear end side surface (rear end surface) of the narrowed portion 161 are pressed against the front end surface of the sleeve large diameter portion 32 and the rear end surface of the hosel 16. Thereby, since the sleeve 30 and the hosel 16 are fixed, the head 10 and the shaft 20 are fixed.

  In the present embodiment, in addition to the bore through weight WB (that is, the bolt head 42), the weight WT is provided on the outer periphery of the shaft 20 at a position separated from the rear end surface of the sleeve 30 by a predetermined distance Lw (described later) on the rear end side. Is provided. Since the weight WT is provided on the tip side, that is, on the tip side as viewed from the entire shaft 20, it can also be referred to as a tip weight WT. Such a chip weight WT can be formed by, for example, winding a flexible metal sheet such as lead around the outer periphery of the shaft 20. In this case, it is desirable to use a lead sheet as the metal sheet so as to conform to the rules. Further, a metal or resin member may be fixed to the inner surface of the shaft 20 as the chip weight. Furthermore, not only the weight attached to the shaft 20 but, for example, in the manufacturing process of the shaft 20, when the prepreg is wound in multiple layers, a prepreg or metal sheet to which metal powder of high specific gravity such as tungsten is attached is sandwiched. Thus, a heavy object may be formed on the shaft 20.

  2 and 3 are explanatory diagrams for explaining the functions of the two weights WB and WT (FIG. 1) of the golf club 1. FIG. 2 shows the behavior of the golf club 1 when the golf club 1 hits the ball BL. In FIG. 2, the two weights WB and WT are not shown. As shown in FIG. 2, when the head 10 of the golf club 1 hits the ball BL, an impact force is applied from the ball BL to the head 10 as a reaction of the hit. The impact force applied to the head 10 from the ball BL causes the shaft 20 to bend from the rear end (head connection end) of the connecting portion of the shaft 20 to the head 10 toward the rear end side when the shaft 20 is bent. It is transmitted like a wave at a transmission speed determined by the mechanical characteristics (for example, the density and Young's modulus of the shaft 20).

  Incidentally, the trajectory (ball trajectory) drawn by the ball after hitting the ball BL with the golf club 1 is determined by the behavior of the head 10 during the period (impact) in which the face 11 and the ball BL are in contact. As described above, since the impact force from the ball BL is transmitted to the shaft 20 like a wave, the impact force is applied only to the distal end portion (shaft distal end portion) ST of the shaft 20 during the impact. The distal end ST is bent. Such behavior of the shaft tip ST affects the behavior of the head 10, and therefore the mechanical characteristics of the shaft tip ST to which the impact force is transmitted during impact affect the behavior of the head 10 during impact. Give and affect the trajectory. Therefore, the head 10 and the shaft tip ST in the range (impact transmission range) in which the impact force received from the ball BL during the impact is transmitted affect the trajectory of the ball BL after the impact, so It can be said that there is.

  As can be seen from FIG. 2, the head 10 and the shaft tip ST in the impact transmission range pass through the center of gravity of the portion included in the impact transmission range of the golf club 1 when the ball BL collides with the face 11. It moves so as to rotate about an axis (vertical rotation axis) AH parallel to both the ground and the surface of the face 11 (face surface). Here, the ground is a so-called ground assumed when the head 10 is designed. The longitudinal rotation axis AH is a rotation axis on which the impact transmission range (that is, the head 10 and the shaft tip portion ST) rotates during impact due to the impact force received from the ball BL. In FIG. 2, for convenience of illustration, the longitudinal rotation axis AH is drawn at a position away from the head 10, but the longitudinal rotation axis AH is usually located near the crown 12 (FIG. 1) of the head 10.

  FIG. 3A and FIG. 3B are explanatory diagrams for explaining the mechanical characteristics of the impact transmission range. In the golf club 1 of the present embodiment, the bore through weight WB is configured as a bolt head 42 of the fixing bolt 40 (FIG. 1) and is located inside the head 10. Therefore, as shown in FIG. 3, the bore through weight WB is located on the sole 13 side of the impact transmission range.

  On the other hand, the tip weight WT is provided at a position away from the rear end surface of the sleeve 30 to the rear end side by a distance Lw. In general, the sleeve 30 has higher rigidity than the shaft 20 and most of the sleeve 30 is in contact with the head 10, so that the behavior during impact can be handled as being almost integral with the head 10. Therefore, in the golf club 1 of the present embodiment, the position of the rear end surface of the sleeve 30 is the rear end (head connection end) 21 of the connecting portion of the shaft 20 between the shaft 20 and the head 10. The distance between the tip weight WT and the head connection end 21 (connection end chip weight distance) Lw is determined based on the impact time (impact time) in which the face 11 and the ball BL are in contact with each other and the transmission of the impact force on the shaft 20. By making the length less than the length determined by the speed (impact transmission speed), the tip weight WT can be within the shock transmission range. It should be noted that the connection end tip weight distance Lw may be set to 300 mm or less because the impact time is usually about 0.5 ms and the impact transmission speed of the shaft 20 is about 600 m / s in a driver. In addition, since the impact time is shorter than that of the driver in fairway wood, iron or the like, the connection end chip weight distance Lw is set to be shorter (for example, 200 mm) than that of the driver.

  Also in FIG. 3, the longitudinal rotation axis AH is drawn at a position away from the head 10 as in FIG. 2, but the longitudinal rotation axis AH is located near the crown 12 of the head 10. It is located on the front end side with respect to the rear end surface. Therefore, by disposing the chip weight WT on the rear end side with respect to the head connection end 21, the position of the chip weight WT is on the rear end side with respect to the vertical rotation axis AH.

  As described above, in the golf club 1 of the present embodiment, the bore through weight WB and the tip weight WT can be disposed at the front end side and the rear end side end of the impact transmission range. Therefore, the inertia moment (effective vertical inertia moment) by the portion included in the impact transmission range of the golf club 1 with respect to the rotation about the vertical rotation axis AH shown in FIG. It can be made larger than the case where at least one of them is not provided. Even when the ball hitting point indicated by the x mark is deviated from the sweet spot SS to the crown 12 side (up) or the sole 13 side (down) due to the increase in the effective vertical moment of inertia, the ball is hit with the sweet spot SS. The change in the behavior of the head 10 during the impact is suppressed, and the change in the trajectory is suppressed. Therefore, according to the present embodiment, it is possible to further reduce the difference in flight distance due to the vertical displacement of the hit point. Note that the two weights WB and WT provided on the golf club 1 are not necessarily arranged at the front end side and the rear end side end of the impact transmission range. Generally, two weights are positioned at a position lower than the vertical rotation axis AH (a position where the distance from the ground is shorter than the distance between the vertical rotation axis AH and the ground) and a position higher than the vertical rotation axis AH (the ground) The distance between the vertical rotation axis AH and the ground is longer than the distance between the ground and the ground), the effective vertical moment of inertia is increased, and the flying distance difference due to vertical displacement of the hitting point is further reduced. Can do. However, it is preferable that the weight on the tip side is provided on the tip side (sole 13 side) of the head 10 in order to increase the effective vertical inertia moment and to reduce the difference in flight distance due to the vertical displacement of the hitting point. The weight on the rear end side is preferably provided at the rear end of the impact transmission range.

  On the other hand, in the golf club 1 of the present embodiment, the bore through weight WB and the tip weight WT are both provided on the shaft axis AS. Therefore, the moment of inertia of the golf club 1 (the shaft axis moment of inertia), that is, the moment of inertia around the shaft axis AS, about the rotation about the shaft axis AS shown in FIG. The increase is suppressed by providing. As described above, according to the present embodiment, an increase in the shaft axis moment of inertia due to the provision of the weights WB and WT is suppressed, so that the head 10 when swinging the golf club 1 is provided even when the weights WB and WT are provided. It is possible to maintain a good return.

  In this embodiment, the bolt head 42 of the fixing bolt 40 used for fixing the shaft 20 to the head 10 has a function as the bore through weight WB. However, a bore through weight may be provided in another mode. Is possible. For example, the shaft may be directly fixed to the hosel by bonding or the like without using the sleeve 30, and the bore through weight may be directly attached to the head. In this case, the head connection end is the position of the rear end face of the hosel on the shaft. Further, the weight on the tip side does not necessarily have to be attached to the position of the hole (bore) in the center of the hosel 16. However, in order to suppress an increase in the shaft axis moment of inertia due to the weight on the tip side, the weight on the tip side is preferably provided in the vicinity of the shaft axis AS such as the heel portion of the head, and is provided on the shaft axis AS. Is more preferable.

  DESCRIPTION OF SYMBOLS 1 ... Golf club, 10 ... Head, 11 ... Face, 12 ... Crown, 13 ... Sole, 14 ... Heel, 15 ... Toe, 16 ... Hosel, 20 ... Shaft, 21 ... Head connection end, 30 ... Sleeve, 31 ... Sleeve Main body 32 ... Sleeve large diameter part 33 ... Female thread part 39 ... Shaft insertion hole, 40 ... Fixing bolt, 41 ... Bolt shaft part, 42 ... Bolt head, 49 ... Tool engagement hole, 161 ... Narrow part, AH ... vertical axis, AS ... shaft axis, BL ... ball, SS ... sweet spot, ST ... shaft tip, WB ... bore through weight, WT ... chip weight

Claims (3)

A golf club having a shaft and a head provided on the tip side of the shaft,
The first weight and the second weight are within an impact transmission range in which an impact force received from the ball is transmitted during an impact period in which the head and the ball are in contact with each other when the ball is hit with the head. Things are provided,
The first heavy object is disposed at a position lower than an axis passing through the center of gravity of the portion of the golf club in the impact transmission range and parallel to both the ground surface and the face surface of the head;
The second heavy object is disposed at a position higher than the axis.
Golf club.   The golf club according to claim 1, wherein the first heavy article is disposed in the vicinity of an axis of the shaft.   The second heavy object is between a position of a head connection end that is a rear end of a connection portion of the shaft and the head in the shaft, and a position that is 300 mm away from the head connection end toward the rear end side. The golf club according to claim 1, wherein the golf club is arranged.

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