JP2008173314A - Golf club head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a head allowing a wide-range movement of the center of gravity and having a high freedom degree in adjusting the position of the center of gravity. <P>SOLUTION: This head 2 consists of a head body h1 and a rotary body k1. The center G1 of gravity of the rotary body k1 is moved by the rotation of the rotary body k1. The rotary body k1 is rotated around a rotary axis z1. The rotary body k1 has a ring-shaped member 16 and a weight member 18 attached to the ring-shaped member 16. The weight member 18 is moved along a circle by the rotation of the ring-shaped member 16. The rotary body k1 is fastened with a screw. The center Gh of gravity of the head body h1 is positioned inside a moving trajectory of the center G1 of gravity of the rotary body k1 in a projection picture to a reference plane H. The moving trajectory is situated on the same plane. An angle θ formed between a plane P1 containing the moving trajectory and the reference plane H is 20° or less in the head in a standard condition. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a golf club head.

  The position of the center of gravity of the golf club head affects the characteristics of the head. The position of the center of gravity of the head affects the position of the sweet spot. The position of the center of gravity of the head affects the moment of inertia. The position of the center of gravity of the head affects the launch angle of the hit ball and the spin amount. The optimum center-of-gravity position can be related to the loft angle of the head.

  The hit points differ depending on the golfer. Depending on the golfer, the preferred trajectory varies. Depending on the golfer, the head speed and head trajectory are different. The position of the center of gravity for increasing the flight distance varies depending on the golfer. The optimal center of gravity position depends on the golfer. The optimal center of gravity position depends on the golfer's condition.

It would be useful if adjustment to the optimal center of gravity was possible. Japanese Patent Application Laid-Open No. 11-319167 discloses a golf club head having a rotatable insert material and a plurality of weights, the receiving position being adjustable by rotation of the insert material. Japanese Patent Application Laid-Open No. 9-28844 discloses a golf club head provided with a weight member movable in the front-rear direction.
JP 11-319167 A JP 9-28844 A

  In the conventional golf club heads described in the above publications, the range of movement of the center of gravity is limited. In the head described in Japanese Patent Application Laid-Open No. 11-319167, the insert material is provided in the rear part of the head, so that the range of movement of the center of gravity is limited. In the head described in Japanese Patent Laid-Open No. 9-28844, the weight member moves in the front-rear direction, and therefore the range of movement of the center of gravity is limited.

  An object of the present invention is to provide a golf club head that can move a center of gravity over a wide range and has a high degree of freedom in adjusting the position of the center of gravity.

  The golf club head according to the present invention has a head body and a rotating body. The center of gravity of the rotating body moves as the rotating body rotates. In the projected image on the reference plane, the center of gravity of the head body is located inside the movement locus of the center of gravity of the rotating body.

  Preferably, the rotating body includes a ring-shaped member and a weight member attached to the ring-shaped member. The weight member moves along a circle by the rotation of the ring-shaped member.

  Preferably, the movement trajectory exists on the same plane, and in the head in the reference state, an angle θ formed by the plane including the movement trajectory and the reference plane is 20 degrees or less.

  According to the present invention, the degree of freedom in the movement direction of the center of gravity of the head is increased.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

  FIG. 1 is a perspective view of a head 2 according to an embodiment of the present invention, and FIG. 2 is a side view of the head 2 viewed from the toe side. FIG. 3 is a bottom view of the head 2 as viewed from the sole side. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. FIG. 5 is an enlarged cross-sectional view taken along line VV in FIG.

  The head 2 has a face portion 4, a crown portion 6, a sole portion 8, a side portion 10 and a hosel portion 12. The hosel portion 12 includes a shaft hole (not shown) for inserting and bonding the shaft. The face portion 4 has a face surface 14. The face surface 14 is an outer surface of the face portion 4. Although not shown, a face line is provided on the face surface 14. The head 2 is a wood type golf club head. The inside of the head 2 is a cavity. The head 2 is a hollow golf club head. The golf club having the head 2 includes the head 2, the shaft, and a grip.

  The head 2 has a head main body h1 and a rotating body k1. The head 2 includes a head main body h1 and a rotating body k1. The head body h <b> 1 has a face part 4, a crown part 6, a side part 10, and a hosel part 12. The head body h <b> 1 constitutes a part of the sole portion 8. The rotating body k1 is provided on the sole portion 8. The rotating body k1 constitutes a part of the sole portion 8. The head body h1 is made of a titanium alloy. The rotating body k1 is exposed to the outside of the head.

  The rotating body k1 includes a ring-shaped member 16 and a weight member 18. As shown in FIGS. 4 and 5, the head main body h <b> 1 has a ring-shaped groove 20. As shown in FIG. 5, the groove 20 has an inner peripheral surface 22 and an outer peripheral surface 24. The shape of the groove 20 corresponds to the ring-shaped member 16. The diameter of the inner peripheral surface 22 is substantially the same as the inner diameter d1 of the ring-shaped member 16. The diameter of the outer peripheral surface 24 is substantially the same as the outer diameter d2 of the ring-shaped member 16. As shown in FIG. 4, the thickness b <b> 1 of the ring-shaped member 16 is substantially the same as the depth of the groove 20. The ring-shaped member 16 is fitted into the ring-shaped groove 20 with almost no gap. The ring-shaped member 16 and the ring-shaped groove 20 are arranged substantially coaxially.

  The ring-shaped member 16 has a connecting part 16a, an inner part 16b, and an outer part 16c. The connection part 16a is a ring-shaped flat plate. The outer surface of the connecting portion 16 a constitutes a part of the sole surface of the head 2. The inner part 16b is ring-shaped. The inner side part 16b is provided in the inner periphery of the connection part 16a. The inner portion 16 b extends to one side in the radial direction of the ring-shaped member 16. When the ring-shaped member 16 rotates, the inner peripheral surface of the inner portion 16 b rubs against the peripheral surface 22 of the groove 20. The outer side part 16c is provided in the outer periphery of the connection part 16a. The outer portion 16 c extends to one side in the radial direction of the ring-shaped member 16. When the ring-shaped member 16 rotates, the outer peripheral surface of the outer portion 16 c rubs against the peripheral surface 24 of the groove 20.

  The ring-shaped groove 20 guides the rotation of the ring-shaped member 16. The ring-shaped member 16 can rotate inside the ring-shaped groove 20. The rotation angle is not restricted. In FIG. 3 and FIG. 4, what is indicated by reference numeral z <b> 1 is the rotation axis z <b> 1 of the ring-shaped member 16. The rotation axis z1 is substantially the same as the axis z2 of the groove 20. The rotation axis z1 is substantially the same as the axis z3 of the ring-shaped member 16.

  The weight member 18 is a columnar member. The ring-shaped member 16 is provided with a hole 23 for attaching the weight member 18. The shape of the hole 23 corresponds to the shape of the weight member 18. The inner diameter of the hole 23 is substantially equal to the outer diameter of the weight member 18. The weight member 18 is joined to the ring-shaped member 16 by press-fitting and / or adhesion.

  The head 2 has a fixing mechanism that fixes the rotation of the rotating body k1 in a plurality of phases. This fixing mechanism fixes the rotation of the ring-shaped member 16 in a plurality of phases. This fixing mechanism fixes the rotation of the ring-shaped member 16 by screwing. This fixing mechanism fixes the rotating body k1 to the head body h1.

  The fixing mechanism includes a hole 26 provided in the ring-shaped member 16, a screw 28, and a screw hole 30 provided in the head main body h. The hole 26 is a through hole. The hole 26 can be inserted with a screw 28. The hole 26 is a screw hole that can be screwed into the screw 28. The hole 26 may not be a screw hole. The screw hole 30 is screwed with the screw 28. The rotation of the ring-shaped member 16 is fixed by this screwing. By this screwing, the ring-shaped member 16 is fixed to the head main body h. The screw 28 is a component of the rotating body k1.

  The holes 26 are provided at equal intervals in the circumferential direction of the ring-shaped member 16. The holes 26 are provided every 90 degrees in the circumferential direction of the ring-shaped member 16. All the holes 26 have the same distance from the axis z3. There are four holes 26. The number of holes 26 is not limited. From the viewpoint of ensuring the fixation, the number of the holes 26 is preferably 2 or more, and more preferably 3 or more. From the viewpoint of simplifying the screwing operation for fixing, the number of the holes 26 is preferably 8 or less, more preferably 6 or less, and particularly preferably 4 or less. From the viewpoint of evenly distributing the force acting on the screw 28 at the time of fixed hitting, when N1 holes 26 are provided, these holes 26 are preferably arranged every (360 / N1) degrees.

  The screw hole 30 is provided on the bottom surface 32 of the groove 20. The screw holes 30 are provided at equal intervals in the circumferential direction of the groove 20. The screw holes 30 are provided every 30 degrees in the circumferential direction of the groove 20. There are twelve screw holes 30. In FIG. 3, the screw holes 30 are indicated by broken lines. In FIG. 3, four screw holes 30 out of twelve screw holes 30 are hidden by screws 28. The same number of screws 28 as the number of screw holes 30 are used. There are four screws 28.

  All the screw holes 30 have the same distance from the axis z2. The position of the hole 26 in the radial direction is the same as the position of the screw hole 30 in the radial direction. The radial direction is a radial direction with respect to the axis z1 and is a radial direction with respect to the axis z2 and the axis z3.

  The number of screw holes 30 is not limited. From the viewpoint of increasing the degree of freedom of the phase angle that can be fixed, the number of screw holes 30 is preferably 4 or more, more preferably 6 or more, more preferably 8 or more, and particularly preferably 12 or more. From the viewpoint of improving the strength of the head body h, the number of screw holes 30 is preferably 24 or less, and more preferably 18 or less. From the viewpoint of evenly distributing the force acting on the screw 28 at the time of fixed hitting, when N2 screw holes 30 are provided, these holes 26 are preferably arranged every (360 / N2) degrees. .

  In a state where the screw hole 30 is screwed, the head of the screw hole 30 is exposed to the outside. The surface of the head of the screw hole 30 constitutes a part of the sole surface. The exposed screw hole 30 can be easily tightened. The exposed screw hole 30 can be easily loosened. The screw hole 30 can be easily rotated by a tool such as a screwdriver. The fixing of the ring-shaped member 16 and the release of this fixing are easy. The ring-shaped member 16 can be fixed every 30 degrees.

  The weight distribution of the rotating body k1 is biased in the circumferential direction. The weight distribution of the rotating body k1 is concentrated on the portion where the weight member 18 exists. The center of gravity G1 of the rotating body k1 does not exist on the rotation axis z1. The center of gravity G1 of the rotating body k1 is present at a position separated from the rotation axis z1 by a predetermined distance r.

  As the ring-shaped member 16 rotates, the weight member 18 moves along a circle. Due to the rotation of the rotating body k1, the center of gravity G1 of the rotating body k1 moves. The center of gravity G1 moves along a circle by the rotation of the rotating body k1. In FIG. 3 and FIG. 4, what is indicated by a two-dot chain line is a movement locus t1 of the center of gravity G1. The locus of the center of gravity G1 accompanying the rotation of the rotating body k1 is the movement locus t1. The movement trajectory t1 is circular. The center of the movement locus t1 exists on the rotation axis z1. The movement locus t1 exists on the sole surface side with respect to the center of gravity Gh of the head main body h1. The rotating body k1 contributes to lowering the center of gravity of the head 2.

  As shown in FIG. 4, the center of gravity Gh of the head main body h1 is located in the hollow portion of the head. The center of gravity Gh of the head body h1 is different from the center of gravity G1 of the rotating body k1. The center of gravity Gh can be measured by removing the rotary body k1 from the head 2. The center of gravity g of the head 2 is at a position different from the center of gravity Gh. The center of gravity of the head 2 is at a position different from the center of gravity G1.

  In the present application, a reference plane H is defined. The reference plane means a plane parallel to the horizontal plane h in a reference state in which the head 2 is placed on the horizontal plane h at a predetermined lie angle and real loft angle. The predetermined lie angle and real loft angle are set for each type of golf club. The predetermined lie angle and real loft angle are listed in, for example, a product catalog. In FIG. 4, the reference plane H is indicated by a solid line.

  In the projected image on the reference plane H, the center of gravity Gh of the head body is located inside the movement locus of the center of gravity G1. FIG. 6 shows a projection image onto the reference plane H. In FIG. 6, F (Gh) indicates a projected image of the center of gravity Gh. In FIG. 6, F (t1) indicates a projected image of the movement locus t1. The projected image F (t1) is annular. The projected image F (t1) is a single line. The projected image F (t1) is an endless curve. In the present embodiment, the projected image F (t1) is a circle. This is because an angle θ described later is 0 degree. Depending on the value of the angle θ, the projected image F (t1) can be an ellipse or the like. As shown in FIG. 6, the projection image F (Gh) is located inside the projection image F (t1). In FIG. 6, an orthogonal axis with the toe / heel direction as the vertical axis, the face / back direction as the horizontal axis, and the projected image F (Gh) as the origin is appended.

  In FIG. 4, the movement trajectory t1 is shown as a single straight line (two-dot chain line). The movement locus t1 is on the same plane. The movement locus t1 exists on the plane P1. In FIG. 4, a part of the plane P1 is shown as a single straight line (solid line). All points on the movement locus t1 are on the plane P1.

  The rotating body k1 can rotate 360 degrees. The weight member 18 can rotate 360 degrees around the rotation axis z1. The weight member 18 can be fixed on the toe side of the center of gravity Gh of the head body h1. The weight member 18 can be fixed on the heel side of the center of gravity Gh. The weight member 18 can be fixed on the face side of the center of gravity Gh. The weight member 18 can be fixed on the back side of the center of gravity Gh.

  The rotating body k1 can be fixed in a state where the center of gravity G2 of the weight member 18 is disposed on the toe side of the center of gravity Gh. The rotating body k1 can be fixed in a state where the center of gravity G2 of the weight member 18 is disposed on the heel side of the center of gravity Gh. The rotating body k1 can be fixed in a state where the center of gravity G2 of the weight member 18 is disposed on the face side of the center of gravity Gh. The rotating body k1 can be fixed in a state where the center of gravity G2 of the weight member 18 is disposed on the back side of the center of gravity Gh.

  The rotating body k1 can be fixed in a state where the center of gravity G2 is disposed on the toe side and the back side of the center of gravity Gh. The rotating body k1 can be fixed in a state where the center of gravity G2 is disposed on the toe side and the face side of the center of gravity Gh. The rotating body k1 can be fixed in a state where the center of gravity G2 is disposed on the heel side and the face side of the center of gravity Gh. The rotating body k1 can be fixed in a state where the center of gravity G2 is disposed on the heel side and the back side of the center of gravity Gh.

  The rotating body k1 can be fixed in a state where the center of gravity G1 of the rotating body k1 is disposed on the toe side of the center of gravity Gh. The rotating body k1 can be fixed in a state where the center of gravity G1 is disposed on the heel side of the center of gravity Gh. The rotating body k1 can be fixed in a state where the center of gravity G1 is disposed on the face side of the center of gravity Gh. The rotating body k1 can be fixed in a state where the center of gravity G1 is disposed on the back side of the center of gravity Gh.

  The rotating body k1 can be fixed in a state where the center of gravity G1 is disposed on the toe side and the face side of the center of gravity Gh. The rotating body k1 can be fixed in a state where the center of gravity G1 is disposed on the toe side and the back side of the center of gravity Gh. The rotating body k1 can be fixed in a state where the center of gravity G1 is disposed on the heel side and the face side of the center of gravity Gh. The rotating body k1 can be fixed in a state where the center of gravity G1 is disposed on the heel side and the back side of the center of gravity Gh.

  The rotating body k1 can be fixed in a state where the head gravity center g is moved to the toe side relative to the gravity center Gh. The rotating body k1 can be fixed in a state where the head gravity center g is moved to the heel side with respect to the gravity center Gh. The rotating body k1 can be fixed in a state where the head gravity center g is moved to the face side with respect to the gravity center Gh. The rotating body k1 can be fixed in a state where the head center of gravity g is moved to the back side from the center of gravity Gh. The moving direction of the center of gravity g of the head by the rotating body k1 includes the toe side, the heel side, the face side, and the back side. The moving direction of the center of gravity g of the head by the rotating body k1 includes the toe side and the face side, the toe side and the back side, the heel side and the face side, and the heel side and the back side. The rotational body k1 increases the degree of freedom in the direction of movement of the head center of gravity g. The moving range of the center of gravity g of the head can be widened by the rotating body k1.

  The center of gravity g of the head can be moved to the toe side of the center of gravity Gh by the rotating body k1. When the center of gravity g of the head is moved to the toe side, the flight distance when the hit point is shifted to the toe side increases. When the head center of gravity g is moved to the toe side, the center of gravity distance increases. The increase in the center of gravity distance makes it difficult for the face to return in the event of an impact, and the hook is suppressed.

  The head center of gravity g can be moved to the heel side with respect to the center of gravity Gh by the rotating body k1. When the center of gravity g of the head is moved to the heel side, the flight distance when the hit point is shifted to the heel side increases. When the head center of gravity g is moved to the heel side, the center of gravity distance decreases. The reduction in the center of gravity distance makes it easier for the face to return on impact and suppresses slicing.

  The head center of gravity g can be moved to the face side of the center of gravity Gh by the rotating body k1. When the center of gravity g of the head is moved to the face side, the depth of the center of gravity becomes shallow and the height of the sweet spot becomes low. When the sweet spot height decreases, the launch angle tends to increase due to the so-called gear effect, and the backspin amount tends to decrease. A high launch angle and a low backspin amount increase the flight distance.

  The head center of gravity g can be moved to the back side of the center of gravity Gh by the rotating body k1. When the center of gravity g of the head is moved to the back side, the depth of the center of gravity increases and the moment of inertia of the head increases. Due to the increase of the moment of inertia, the rotation of the head is small when the hit point is shifted to the toe side and the heel side. Due to the increase of the moment of inertia, there is little variation in hitting direction.

  As described above, the reference plane H is indicated by a single solid line in FIG. In the present embodiment, the reference plane H is orthogonal to the rotation axis z1. In the present embodiment, the angle θ formed by the plane P1 including the movement locus t1 and the reference plane H is 0 degree. When the angle θ is 0 degree, it is difficult to show the angle θ in the drawing. In FIG. 4, an imaginary reference plane H1 is also shown in order to clearly show the angle θ. The virtual reference plane H1 is indicated by a broken line. In FIG. 4, what is indicated by a double arrow θ is an angle formed by the reference plane H1 and the plane P1.

  At the time of hitting, the head 2 collides with the ball while moving in a direction substantially along the reference plane H. The impact force applied from the ball to the head 2 at the time of hitting acts in a direction substantially along the reference plane H. As the angle θ increases, the force in the direction of the rotation axis z1 acting on the rotating body k1 increases. The force in the direction of the rotation axis z1 can act in the direction of dropping the rotating body k1. The force in the direction of the rotation axis z1 tends to cause deformation and sound generation of the rotating body k1. From the viewpoint of suppressing the dropout and deformation of the rotating body k1 and suppressing the noise caused by the rotating body k1, the angle θ is preferably 20 degrees or less, more preferably 10 degrees or less, and particularly preferably 5 degrees or less.

  From the viewpoint of expanding the moving range of the center of gravity g of the head and enhancing the effect of adjusting the position of the center of gravity, the radius r of the movement locus t1 is preferably 5.0 mm or more, more preferably 10.0 mm or more, and particularly preferably 15.0 mm or more. From the viewpoint of suppressing an excessive weight increase of the rotating body k1 and increasing the strength of the rotating body k1. The radius r is preferably 30.0 mm or less, more preferably 25.0 mm or less, and particularly preferably 20.0 mm or less.

  From the viewpoint of enhancing the effect of adjusting the position of the center of gravity by expanding the movement range of the head center of gravity g, the radius R (d2 / 2) of the ring-shaped member 16 is preferably 25.0 mm or more, more preferably 30.0 mm or more, 35. 0 mm or more is particularly preferable. From the viewpoint of suppressing an excessive weight increase of the rotating body k1 and increasing the strength of the rotating body k1. The radius R is preferably 50.0 mm or less, more preferably 45.0 mm or less, and particularly preferably 40.0 mm or less. The center of gravity g of the head is the center of gravity of the head 2.

  From the viewpoint of enhancing the effect of moving the center of gravity position while suppressing the size of the rotating body k1, the ratio (r / R) of the radius r of the movement locus t1 to the radius R is preferably 0.2 or more, and 0.3 or more. Is more preferable, and 0.4 or more is particularly preferable. In order to increase the ratio (r / R), a method of arranging the weight member 18 on the outer side in the radial direction or a method of reducing the weight of the ring-shaped member 16 can be considered. If the weight member 18 is disposed extremely outside in the radial direction, the ring-shaped member 16 and the weight member 18 may not be sufficiently joined. If the ring-shaped member 16 is excessively lightened, the strength of the ring-shaped member 16 tends to be insufficient. From the viewpoint of increasing the fixing strength of the weight member 18 and increasing the strength of the ring-shaped member 16, the ratio (r / R) is preferably 0.8 or less, more preferably 0.7 or less, and particularly preferably 0.6 or less.

  From the viewpoint of enhancing the effect of adjusting the position of the center of gravity by expanding the movement range of the center of gravity g of the head, the intersection c1 of the straight line L passing through the center of gravity Gh of the head body h1 and perpendicular to the reference plane H, The distance M with respect to FIG. 4) is preferably 4.0 mm or more, more preferably 5.0 mm or more, and particularly preferably 6.0 mm or more. In order to increase the distance M, it is necessary to bring the rotating body k1 closer to the end of the head 2. The end side of the head 2 includes a back side, a face side, a toe side, a heel side, and the like. In order to accommodate the rotary body k1 on the end side of the head 2, it is necessary to reduce the size of the rotary body k1. The distance M is preferably 15.0 mm or less, more preferably 12.0 mm or less, and particularly preferably 10.0 mm or less from the viewpoint of suppressing the downsizing of the rotating body k1 and enhancing the effect of adjusting the position of the center of gravity. The straight line L and the distance M are not shown.

  In light of enhancing the effect of adjusting the position of the center of gravity, the specific gravity H1 of the weight member 18 is preferably 7.0 or greater, more preferably 10.0 or greater, and particularly preferably 12.0 or greater. From the viewpoint of suppressing an excessive weight increase of the rotating body k1 or increasing the strength of the rotating body k1, the specific gravity H1 is preferably 20.0 or less, more preferably 17.0 or less, and particularly preferably 15.0 or less. preferable.

  The material of the weight member 18 is not particularly limited. As the material of the weight member 18, for example, a metal containing one or more of tungsten, copper and / or nickel is suitable.

  From the viewpoint of enhancing the effect of adjusting the position of the center of gravity by expanding the movement range of the head center of gravity g, the weight member 18 preferably has a weight of 2 g or more, more preferably 7 g or more, and even more preferably 10 g or more. From the viewpoint of suppressing an excessive increase in head weight or suppressing a decrease in strength due to excessive weight reduction of the head main body h1, the weight member 18 preferably has a weight of 25 g or less, and more preferably 20 g or less.

  From the viewpoint of increasing the strength of the ring-shaped member 16, the specific gravity H2 of the ring-shaped member 16 is preferably 2.0 or more, more preferably 3.0 or more, and particularly preferably 4.0 or more. From the viewpoint of suppressing an excessive weight increase of the rotating body k1 and increasing the strength of the rotating body k1, the specific gravity H2 is preferably 8.0 or less, more preferably 7.0 or less, and particularly preferably 5.0 or less. preferable.

  From the viewpoint of setting the specific gravity H2 of the ring-shaped member 16 in a preferable range, the material of the ring-shaped member 16 is preferably aluminum, an aluminum alloy, pure titanium, or a titanium alloy. From the viewpoint of strength, the material of the ring-shaped member 16 is preferably pure titanium or a titanium alloy. As the titanium alloy, α + β series and β series titanium alloys are suitable. As this titanium alloy, Ti-6Al-4V (specific gravity 4.42), Ti-10V-2Fe-3Al (specific gravity 4.65), Ti-15Al-3Cr-3Sn-3Al (specific gravity 4.76), Ti-4 .5Al-3V-2Fe-2Mo (specific gravity 4.60), Ti-5.5Al-1Fe (specific gravity 4.38), Ti-15Mo-5Zr-3Al (specific gravity 4.95), Ti-22V-4Al (specific gravity) 4.69), Ti-15V-6Cr-4Al (specific gravity 4.72 to 4.74), and the like.

  From the viewpoint of increasing the strength of the ring-shaped member 16, the weight of the ring-shaped member 16 is preferably 3 g or more, and more preferably 5 g or more. From the viewpoint of increasing the weight difference with the weight member 18 and enhancing the effect of adjusting the position of the center of gravity, the weight of the ring-shaped member 16 is preferably 15 g or less, more preferably 10 g or less, and particularly preferably 8 g or less.

  From the viewpoint of increasing the strength of the screw 28, the specific gravity of the screw 28 is preferably 2.5 or more, more preferably 2.6 or more, and particularly preferably 2.7 or more. From the viewpoint of suppressing an excessive weight increase of the rotating body k1 and enhancing the effect of adjusting the position of the center of gravity, the specific gravity of the screw 28 is preferably 9.0 or less, more preferably 8.5 or less, and particularly preferably 8.0 or less. preferable.

  From the viewpoint of increasing the strength of the screw 28, the weight per screw 28 is preferably 0.2 g or more, and more preferably 0.5 g or more. In light of enhancing the effect of adjusting the position of the center of gravity, the weight per screw 28 is preferably 5 g or less, more preferably 3 g or less, and particularly preferably 2 g or less.

From the viewpoint of enlarging the head body h1 and allowing attachment of the large rotating body k1, the volume of the head 2 is preferably 100 cm ³ or more, more preferably 200 cm ³ or more, more preferably 300 cm ³ or more, and even more preferably 350 cm. ³ or more, particularly preferably 400 cm ³ or more. The effect of adjusting the position of the center of gravity can be enhanced by the large rotating body k1. From the viewpoint of suppressing an excessive increase in head weight and a decrease in durability, the head volume is preferably 600 cm ³ or less, more preferably 500 cm ³ or less.

  The material of the head body h1 is not particularly limited. As the material of the head main body h1, titanium alloy, aluminum alloy, pure titanium, stainless steel and the like are preferable. Further, as the titanium alloy, α + β-based and β-based titanium alloys are suitable. More specifically, Ti-6Al-4V (specific gravity 4.42), Ti-10V-2Fe-3Al (specific gravity 4.65), Ti-15Al-3Cr-3Sn-3Al (specific gravity 4.76), Ti- 4.5Al-3V-2Fe-2Mo (specific gravity 4.60), Ti-5.5Al-1Fe (specific gravity 4.38), Ti-15Mo-5Zr-3Al (specific gravity 4.95), Ti-22V-4Al ( Specific gravity 4.69), Ti-15V-6Cr-4Al (specific gravity 4.72 to 4.74) and the like are preferable. One or more of these materials may be used. In addition to these materials, a resin, particularly a fiber reinforced resin, can be used for a part or all of the head 2. All of the head main body h1 of the present embodiment is made of a titanium alloy. The head main body h1 is prepared by, for example, dividing into a plurality of parts in advance and joining them by welding or adhesion. Various methods such as forging, casting and / or pressing can be adopted as a method of forming each part.

  From the viewpoint of increasing the strength of the head, the weight of the head 2 (total head weight) is preferably 170 g or more, and more preferably 180 g or more. In particular, in the case of a driver head, the total head weight is preferably 210 g or less, and more preferably 200 g or less, from the viewpoint of swing balance and ease of swinging.

  From the viewpoint of improving the durability of the head, the thickness of the head main body h1 at the portion in contact with the rotating body k1 is preferably 0.4 mm or more, more preferably 0.6 m or more, and particularly preferably 0.8 mm or more. From the viewpoint of suppressing the weight of the head body h1 to the extent that installation of the rotating body k1 is allowed, when the head 2 is a hollow head, the thickness of the head body h1 is preferably 3.0 mm or less, and 2.5 mm or less. Is more preferable. The thickness of the head body h1 may be constant or may vary depending on the part.

  The fixing mechanism is not limited to the screw mechanism described above. For example, the fixing mechanism includes a pin that can be protruded and retracted, a ring member that has a plurality of recesses that can engage with the pin, and that can rotate, a weight member provided on the ring member, and the pin And a fixing mechanism that is fixed while the circumferential position (phase) of the weight member is changed by selecting the concave portion that engages with the pin. .

  Hereinafter, the effects of the present invention will be clarified by examples. However, the present invention should not be construed in a limited manner based on the description of the examples.

[Example]
In the same manner as the head 2 described above, the head shown in FIGS. 1 to 5 was obtained. The head body of this head was made of a titanium alloy (specific gravity 4.42). The weight of the weight member of this head is 14 g. The weight member was made of a tungsten nickel alloy (specific gravity 13.5). The ring-shaped member was made of a titanium alloy (specific gravity 4.42). The total weight of the ring-shaped member 16 and the screw 28 of this head is 7 g. The radius r of the movement locus of this head is 20.1 mm. The radius R of the outer periphery of the ring-shaped member in this head is 40.0 mm. The ratio (r / R) of this head is 0.50. As described above, the specific gravity H1 is 13.5 and the specific gravity H2 is 4.42. The angle θ of the head is 0 degree. The distance M of this head is 8.8 mm.

  In the head of the example, specifications and evaluation results when the weight member is fixed so as to be as close to the face side as possible are shown in the “face side” column of Table 1 below. In the head of the example, specifications and evaluation results when the weight member is fixed so that it is as close to the back side as possible are shown in the “Back side” column of Table 1 below. In the head of the example, specifications and evaluation results when the weight member is fixed so that the position of the weight member is as close as possible to the toe side are shown in the “toe side” column of Table 1 below. In the head of the example, specifications and evaluation results when the weight member is fixed so that the position of the weight member is on the heel side as much as possible are shown in the “heel side” column of Table 1 below.

[Comparative Example 1]
7 is a bottom view of the head 40 of Comparative Example 1 viewed from the sole side, and FIG. 8 is a side view of the head 2 viewed from the toe side. The head 40 includes a face portion 42, a crown portion 44, a sole portion 46, a side portion 48, and a hosel portion 50. The hosel part 50 includes a shaft hole (not shown) for inserting and bonding the shaft. The face portion 42 has a face surface 52. The face surface 52 is an outer surface of the face portion 42. The head 40 is a wood type golf club head. The inside of the head 40 is a cavity. The head 40 is a hollow golf club head.

  The head 40 includes a head main body h2 and a rotating body k2. The head 40 includes a head main body h2 and a rotating body k2. The head main body h <b> 2 includes a face part 42, a crown part 44, a side part 46, and a hosel part 48. The head body h2 constitutes a part of the sole portion 46. The rotating body k2 is provided on the back side of the sole portion 46. The rotating body k2 constitutes a part of the sole portion 46. The head main body h2 is made of the same titanium alloy as the head main body h1. The rotating body k2 is exposed to the outside of the head. The structure and material of the rotating body k2 are the same as the rotating body k1 of the head 2 described above. The rotating body k2 includes a ring-shaped member 54 and a weight member 56. The position where the rotary body k2 is installed is different from that of the rotary body k1. The rotating body k2 is smaller than the rotating body k1. The rotating body k2 is located on the back side of the rotating body k1. The inner diameter d3 of the ring-shaped member 54 is smaller than the inner diameter d1 of the ring-shaped member 16 described above. The outer diameter d4 of the ring-shaped member 54 is smaller than the outer diameter d2 of the ring-shaped member 16 described above.

  In the head of Comparative Example 1, specifications and evaluation results when the weight member 56 is fixed so that the position of the weight member 56 is as close to the face side as possible are shown in the “face side” column of Table 1 below. In the head of Comparative Example 1, the specifications and evaluation results when the weight member 56 is fixed so that the position of the weight member 56 is on the back side as much as possible are shown in the “Back side” column of Table 1 below.

[Comparative Example 2]
A head of Comparative Example 2 was obtained in the same manner as in the example except that the rotating body was not provided.

[3D coordinates of the center of gravity (X, Y, Z)]
The three-dimensional coordinates of the center of gravity G2 of the weight member, the center of gravity G1 of the rotating body, and the center of gravity g of the head are shown in Table 1 below. The three-dimensional coordinates are coordinates in an orthogonal coordinate system including the X axis, the Y axis, and the Z axis. The X axis, the Y axis, and the Z axis are determined based on the head of the embodiment in the reference state. The X axis is oriented in the face-back direction. The value of the X coordinate increases as it goes to the face side, and decreases as it goes to the back side. The X coordinate of the center of gravity Gh of the head main body in the embodiment is 0. The Y axis is oriented in the toe-heel direction. The value of the Y coordinate increases as it goes to the toe side, and decreases as it goes to the heel side. The Y coordinate of the center of gravity Gh of the head main body in the embodiment is 0. The Z axis is oriented in a direction perpendicular to the X axis and the Y axis. The Z coordinate of the horizontal plane h in the reference example is 0. The Z coordinate increases as it goes to the crown side of the head. The Z coordinate becomes a smaller value as it goes to the sole side of the head.

  In Table 1, the three-dimensional coordinates of the center of gravity g in Comparative Example 2 are the same as the three-dimensional coordinates of the center of gravity Gh of the head body of the example.

[Measurement of height of sweet spot SS]
The height of the sweet spot SS from the horizontal plane h in the reference state placed on the horizontal plane h at a predetermined lie angle and real loft angle is shown in Table 1 below as “SS height”. Note that the sweet spot SS is an intersection of a perpendicular drawn from the center of gravity g of the head to the face surface and the face surface.

[Measurement of center of gravity distance]
The distance between the axis of the shaft hole and the center of gravity g of the head is shown in Table 1 below as a “center of gravity distance”.

[Measurement of depth of gravity]
In the head in the reference state, the distance in the face-back direction from the sweet spot SS to the head center of gravity g is shown as the “depth of center of gravity” in Table 1 below. In the head in the reference state, the direction perpendicular to the toe-heel direction described later and parallel to the reference plane is the face-back direction.

[Measurement of right and left moment of inertia]
The moment of inertia of the left and right is INERTIA DYNAMICS INC. MOMENT OF INTERIA MEASURING INSTRUMENT MODEL NO. Measured using 005-002. The right / left moment of inertia is the moment of inertia about the axis y1 passing through the center of gravity g of the head. The axis y1 is an axis perpendicular to the horizontal plane h in the head in the reference state. The values of the left and right moments of inertia are shown in the “left and right” column in Table 1 below.

[Measurement of vertical inertia moment]
The vertical moment of inertia is INERTIA DYNAMICS INC. MOMENT OF INTERIA MEASURING INSTRUMENT MODEL NO. Measured using 005-002. The vertical moment of inertia is the moment of inertia about the axis y2 passing through the center of gravity g of the head. The axis y2 is perpendicular to the axis y1 and is parallel to the toe-heel direction. In the head in the reference state, an intersection line ks between a plane s including the axis of the shaft hole and perpendicular to the horizontal plane h and the horizontal plane h is determined. A direction parallel to the intersecting line ks is a toe-heel direction. The value of the vertical moment of inertia is shown in the “upper and lower” column in Table 1 below.

  “The center of gravity g of the entire head” in Comparative Example 2 corresponds to “the center of gravity Gh of the head main body” in the example. Therefore, the X coordinate and the Y coordinate of “the center of gravity Gh of the head main body” in the embodiment are 0. In the embodiment, the XY coordinates of the center of gravity g of the entire head are moved to the face side with respect to the XY coordinates of the center of gravity Gh, moved to the back side, moved to the toe side, and moved to the heel side. .

  On the other hand, in Comparative Example 1, the moving direction of the head center of gravity g with respect to the center of gravity Gh of the head body is limited. FIG. 9 shows a projection image onto the reference plane H in the first comparative example. As can be understood from FIG. 9, all points on the projection image F (t1) are located on the back side with respect to the projection image F (Gh). From FIG. 9, it is understood that the gravity center moving effect of Comparative Example 1 is limited. In Comparative Example 1, the X coordinate of “the center of gravity Gh of the head body” is 0 mm, and the Y coordinate is 0 mm.

  As Table 1 shows, the example is more effective than the comparative example. From this evaluation result, the superiority of the present invention is clear.

  The present invention can be applied to all golf club heads such as a wood type golf club head, an iron type golf club head, and a putter type golf club head.

FIG. 1 is a perspective view of a golf club head according to a first embodiment of the present invention. FIG. 2 is a side view of the head of FIG. 1 viewed from the toe side. 3 is a bottom view of the head of FIG. 1 as viewed from the sole side. 4 is a cross-sectional view taken along line IV-IV in FIG. FIG. 5 is a cross-sectional view taken along line VV in FIG. FIG. 6 is a projected image of the movement locus of the center of gravity of the rotating body and the center of gravity of the head body in the head of FIG. FIG. 7 is a bottom view of Comparative Example 1 as viewed from the sole side. FIG. 8 is a side view of Comparative Example 1 viewed from the toe side. FIG. 9 is a projected image of the moving locus of the center of gravity of the rotating body and the center of gravity of the head body in the head of Comparative Example 1.

Explanation of symbols

2 ... Head 4 ... Face part 6 ... Back part 8 ... Sole part 10 ... Side part 12 ... Hosel part 14 ... Face surface 16 ... Ring-shaped member 18. ··· Weight member 20 ··· Groove k1 · · · Rotating body G1 · · · Center of gravity of the rotating body G2 · ·· Center of gravity of the weight member Gh · · · Center of gravity of the head body

Claims (4)

A head body and a rotating body;
The center of gravity of this rotating body moves as the rotating body rotates,
A golf club head in which a center of gravity of the head body is located inside a movement locus of the center of gravity of the rotating body in a projected image on a reference plane.   2. The golf club according to claim 1, wherein the rotating body includes a ring-shaped member and a weight member attached to the ring-shaped member, and the weight member moves along a circle by the rotation of the ring-shaped member. head. The movement trajectory exists on the same plane,
3. The golf club head according to claim 1, wherein an angle θ between a plane including the movement locus and the reference plane is 20 degrees or less in the reference state head. Having a head, shaft and grip,
This head
A head body and a rotating body;
The center of gravity of this rotating body moves as the rotating body rotates,
In the projected image on the reference plane, the center of gravity of the head body is a golf club located inside the movement locus of the center of gravity of the rotating body.

Images