Abstract: A vibration reduction golf club grip is disclosed. The golf club grip includes a body having a substantially circular cross-sectional configuration throughout a length thereof. The body includes a first end having a first diameter and a second end having a second diameter. In addition, the body includes a longitudinal cavity, which is opened to the first end, adapted to receive a shaft of a golf club. The body also includes a circular cavity, which is opened to the second end, distributed around the longitudinal cavity, and the circular cavity is filled with a compressible material.

Abstract: A shaft structure with a configurable bending profile is provided for golf clubs, fishing rods, and the like. The shaft structure employs a plurality of tensioned sections. The golfer, in practice, configures the bending profile of a golf shaft by adjusting the internal pressure of the sections in order to change the stiffness of that section. The combination of sections and their associated stiffness results in an advantageous bending profile. The golfer can, at any time and very easily, change the bending profile of the golf shaft.

Abstract: An insert assembly for use with a golf club shaft including an insert and an insert lock.

Abstract: Insert assemblies for use with a golf club shaft including an insert and an insert lock, insert assembly systems, and apparatus for use with insert assemblies.

Abstract: A golf accessory is provided that includes an insert for removably and interchangeably mounting within an interior of a golf club shaft for interchangeably altering a predetermined stiffness or bending moment of the club shaft.

Abstract: A moveable shaft insert assembly about 13 to 18 inches long weighing less than 50 grams is inserted into a hollow golf dub shaft wherein the depth of insertion of the shaft insert assembly may vary from about 1 to 10 inches. Changing the location of the shaft insert assembly allows a player to change the flex of the shaft and thereby optimize the performance of the club dynamics for that player for that day. The shaft insert is held in place by friction between the shaft and the shaft insert assembly. So shaft flex fitting can be administered by a player with or without coaching, and can be revisited at any time by a simple adjustment The shaft inserts are useful on all hollow shaft clubs, and can be retrofitted to existing clubs without removing the grip.

Abstract: A damping element for a golf club is disclosed. The damping element is utilized to reduce an amplitude of vibrations in the golf club. The damping element may be positioned within an interior void of a shaft of the golf club and may exhibit a shape that corresponds with a shape of the void within the shaft. The damping element may exhibit an elongate configuration that extends along at least a portion of the shaft, and the damping element may have the configuration of either a fluid-filled chamber or a foam structure.

Abstract: A golf club grip includes: a grip body including a grip cylinder portion and a grip end portion disposed at one end of the grip cylinder portion and formed with a through-hole for communicating a grip interior with the outside; and a vibration absorption member formed from a viscoelastic material and formed separately from the grip body. The vibration absorption member is removably attached to the grip body. The vibration absorption member includes: a plane portion and a bar-like portion formed integrally with the plane portion. The bar-like portion extends through the through-hole of the grip end portion as projecting inwardly of the grip cylinder portion.

Abstract: A club shaft composed of a club shaft body and a single- or multi-layered coating film covering said club shaft body, wherein said coating film includes a coating layer having good scratch or scuff resistance and high resilience. The club shaft keeps its good appearance owing to its self-healing ability even though it is damaged during carry in a caddie bag.

Abstract: A golf shaft having adjustable stiffness and frequency. A hollow golf shaft has a compression assembly disposed along and within the hollow shaft between the butt end and the bend point of the shaft. The compression assembly places the corresponding end of the shaft in compression and permits rapid and easy adjustment of the shaft stiffness and frequency.

Abstract: A shaft structure with adjustable and self-regulating stiffness is provided for golf clubs, fishing rods, and the like. The shaft structure employs in a presently preferred form a hollow tube in which a piston and a longitudinally spaced platen, each longitudinally slidable, are incorporated. The piston and platen are separated from one another by a spring biasing member. The platen is position controlled longitudinally by a longitudinally extending jackscrew that is rotatable and threadably associated with that platen, but that is longitudinally fixed relative to the tube. The chamber defined on one side of the piston contains a fluid which can be a gas or a liquid, and the platen assumes a position along the shaft which to corresponds to a location where forces on each side of the piston are equalized. Rotating the jack screw causes the platen to move longitudinally, the direction depending upon the direction of jackscrew rotation.

Abstract: A putter or other golf club grip has rigid vibration transmitting protrusions either attached to the club shaft or in intimate contact with both the shaft and the golfer's hands, areas between said protrusions optionally being filled with conventional grip materials. The grip may be placed over existing club shafts like conventional slip-on or wrap-on grips or become an extension thereof. The grips may be attached and weighted in such a manner to further enhance desirable impact vibrational feedback to a golfer's hands further improving a golfer's distance control while reducing off center hits and the resulting distance and directional loss.

Abstract: A golf swing trainer comprises a shaft having a grip end and a head end, and a weighted filling inside the shaft. The weighted filling comprises lead shot, tungsten powder, and polyurethane resin to give the trainer the feel of a regular golf club.

Abstract: In a golf club shaft hollow pipe-shaped and composed of a laminate of prepregs, a vibration absorption member (10) made of an elastic material whose tan &dgr; at 10° C. is not less than 0.7 is installed at least one portion inside the hollow pipe-shaped golf club shaft. The vibration absorption member (10) has a body having a hollow portion, a central part connected to the body through a plurality of connection parts and disposed inside the hollow portion, a plurality of projected parts formed on a peripheral surface of the body and contacting an inner peripheral surface of the pipe-shaped golf club shaft. It is preferable that the weight of the vibration absorption member (10) is not less than 1 g nor more than 10 g, that the number of the connection parts is not less than two nor more than 10, and that the weight of the central part is not less than 10 wt % nor more than 60 wt % of a whole weight of the vibration absorption member.

Abstract: In order to provide an adjusting tool for a golf club to enhance directionability or a driving distance with a flex characteristics of a shaft which is suitable for the taste of a player, there is provided a golf club adjusting tool for adjusting feeling of a golf club in use, characterized by comprising: a fixed portion coupled and fixed in contact with a shaft portion of the golf club in the contact range of 5 to 40 mm in a longitudinal direction; and a vibration absorbing portion projecting in the longitudinal direction of the shaft portion continuously with the fixed portion and out of contact with the shaft portion.

Abstract: A hollow golf club shaft of circular cross-section comprises a tubular cover layer formed from an isotropic material and a tubular core layer formed from a non-isotropic material, wherein the cover layer and the core layer coextend substantially the entire length of the shaft.

Abstract: A hollow golf club shaft of circular cross-section comprises a tubular core layer, a tubular outer layer, and a tubular intermediate member juxtaposed to both the core layer and the outer layer, wherein the core layer and the outer layer coextend substantially the entire length of the shaft.

Abstract: There is provided a golf club shaft in which the shaft is properly flexed at the time of swing and an excessive deformation of the shaft is restricted at the time of impact, a high repelling force is generated, and thereby an initial speed of the ball and the carry of the ball are further improved and which is quite suitable for using a club head having a low center of gravity or a large sized club head. This golf club shaft is filled with the resilient material having a feature in which a rapid application of force against the entire inner part of the hollow shaft or its extremity end causes a high repelling force to be acted on to cause it to be hardly deformed and in turn a gradual application of force causes itself to be easily deformed.

Abstract: The present invention relates to a golf club shaft having improved torsion characteristics comprising a base shaft having an internal surface and an external surface, and at least one wave shaped reinforced part on at least one of said surfaces, said wave shaped reinforced part comprising a plurality of reinforcement pieces. The wave shaped reinforced part is located on at least one of the upper portion, midpoint or lower portion. The golf club shafts of the present invention can be made by applying a base section of a prepreg sheet or assembly having a plurality of finger like elements to a portion of a base shaft, wrapping the finger like elements around the base shaft to provide a wave shaped reinforced part having a plurality of reinforcement pieces, and curing the shaft having the wave shaped reinforced part thereon to produce a golf club shaft having a wave shaped reinforced part.

Abstract: At step 1, a golf ball model is divided into a large number of elements composed of a large number of nodal points in the form of meshes; a physical property of a material for the golf ball is inputted; a simulation is executed by an analysis based on a finite element method, assuming that a golf club head collides with the golf ball; and a strain amount generated in the golf ball model at the time of the collision is computed. At step 2, a stress and a strain component of each element of the golf ball model and coordinate values of the nodal points of each element are outputted; and a value of a stress and a strain of each of six components of each element are computed momently. At step 3, the relationship between the stress and the strain of each component of each element is found from the value of the stress and the strain of each of the six components; and energy loss values of each element are computed.

Abstract: A long shaft comprising a number of axially pre-stressed members, one inside the other, the sum of the bending rigidities of the axially tensioned members is greater than the sum of the bending rigidities of the compression members, is enhanced in bending stiffness such that the end deflection of the shaft under a simultaneous transverse load and the axial force has an end deflection less than the end deflection of the same shaft, which has no pre-stress. The long shaft may be a golf club shaft. An example shows a flex “s” golf shaft, which ordinarily has an end deflection of 3.5 inch, measured from the deflection board, is stiffened into a super stiff shaft with end deflection of 1.54 inch, without having a weight increase or a change of material.

Abstract: A shaft, having a length and two ends, a handle end and an opposite end, is arranged to have two or more concentric, longitudinal members in at least along a major portion of its length; when a lateral load acts at the opposite end, the shaft bends in the conventional primary bending mode of a cantilever beam; the structural members of the shaft is characterized by said concentric members having a substantial, permanent axial pre-stress, wherein each member is either in compression or in tension, constitutes an internal self equilibrating force system.

Abstract: A torque reduction and swing improvement arrangement for a golf club. The arrangement comprises a hallow elongated golf club shaft with a longitudinal axis therewithin, having a handle portion at an upper end thereof, and a golf club head at a lower end of the shaft. A torque reduction arrangement of at least one ribbon of flexible, flat, planar material is disposed longitudinally within the shaft, the ribbon extending from the upper end of the shaft into the lower end thereof. The ribbon is secured within the shaft by a securement arrangement within the shaft.

Abstract: A golf club having suppressed vibration modes is disclosed. The club comprises a shaft, a golf club head, a grip and a plurality of discrete shaft stiffeners. The shaft stiffeners are strategically located along the shaft so as to shift the nodes of at least the second and third flexural vibration modes of the club shaft such that a node of each of the second and third flexural vibration modes occurs both at the club face and within the region underlying the golf club grip. Preferably, the stiffeners are made of a shape memory alloy that can be shrunk onto the outside surface of the shaft, then expanded to permit the position of the stiffeners to be adjusted to suit the boundary conditions imposed by the human user.

Abstract: A golf club having suppressed vibration modes is disclosed. The club comprises a shaft, a golf club head, a grip and a plurality of discrete shaft stiffeners. The shaft stiffeners are strategically located along the shaft so as to shift the nodes of at least the second and third flexural vibration modes of the club shaft such that a node of each of the second and third flexural vibration modes occurs both at the club face and within the region underlying the golf club grip. Preferably, the stiffeners are made of a shape memory alloy that can be shrunk onto the outside surface of the shaft, then expanded to permit the position of the stiffeners to be adjusted to suit the boundary conditions imposed by the human user.

Abstract: A putter comprising a grip having an anatomically correct shape to promote proper grasping of the putter, a shaft having a first end and a second end, wherein the grip is attached to the first end of the shaft, a hosel attached to the second end of the shaft, a head attached to the hosel, the head having a striking face, and an alignment feature of the putter adapted to ensure correct assembly of the head onto the shaft.

Abstract: In a golf club shaft hollow pipe-shaped and composed of a laminate of prepregs, a vibration absorption member (10) made of an elastic material whose tan&dgr; at 10° C. is not less than 0.7 is installed at least one portion inside the hollow pipe-shaped golf club shaft. The vibration absorption member (10) has a body having a hollow portion, a central part connected to the body through a plurality of connection parts and disposed inside the hollow portion, a plurality of projected parts formed on a peripheral surface of the body and contacting an inner peripheral surface of the pipe-shaped golf club shaft. It is preferable that the weight of the vibration absorption member (10) is not less than 1 g nor more than 10 g, that the number of the connection parts is not less than two nor more than 10, and that the weight of the central part is not less than 10 wt % nor more than 60 wt % of a whole weight of the vibration absorption member.

Abstract: A torque reduction and swing improvement arrangement for a golf club. The arrangement comprises a hollow elongated golf club shaft with a longitudinal axis therewithin, having a handle portion at an upper end thereof, and a golf club head at a lower end of the shaft. A torque reduction arrangement of at least one ribbon of flexible, flat, planar material is disposed longitudinally within the shaft, the ribbon extending from the upper end of the shaft into the lower end thereof. The ribbon is secured within the shaft by a securement arrangement within the shaft.

Abstract: A filled shaft for an arrow. The filled shaft includes an elongated cylindrical tube and at least one foamed resin filling substantially the elongated cylindrical tube from end to end. The shaft may further include a lightweight, thin insert in the foamed resin and extending the length of the elongated cylindrical tube.

Abstract: An automatic adjusting device for adjusting the position of the center of gravity of an object comprises a weighting element, an elastic element, a base seat, and a hollow tube body. One end of the weighting element is connected to the elastic element and another end of the elastic element is connected to the base seat, such that the weighting element, the elastic element and the base seat are positioned within the hollow tube body. Initially, the C.G. of the device is located at the handle region of the device, and when the tube body is rapidly swung, the weighting element produces a centrifugal force that is greater than the force of the elastic element to move the weighting element to the front end of the tube body and move the C.G. simultaneously. When the swinging force of the tube body is released, the pulling force of the elastic element will cause the weighting element to be restored to its original position, and the C.G. will be simultaneously restored to its original position as well.

Abstract: An improved aerodynamic golf club shaft is disclosed. The improved aerodynamic golf club shaft comprises a tube that has an exterior with a non-circular cross section. The golf club shaft may have an elliptical exterior cross section in one preferred embodiment. The golf club shaft has a leading edge that is on the half of the shaft aligned with the face of the golf club and a trailing edge on the half of the shaft aligned with the back of the club. A portion of the leading edge of the shaft has a smaller radius of curvature than the leading edge of a equivalently sized shaft having a circular cross section.

Abstract: In order to provide an adjusting tool for a golf club to enhance directionability or a driving distance with a flex characteristics of a shaft which is suitable for the taste of a player, there is provided a golf club adjusting tool for adjusting feeling of a golf club in use, characterized by comprising: a fixed portion coupled and fixed in contact with a shaft portion of the golf club in the contact range of 5 to 40 mm in a longitudinal direction; and a vibration absorbing portion projecting in the longitudinal direction of the shaft portion continuously with the fixed portion and out of contact with the shaft portion.

Abstract: A vibration dampening device (10) for use on the shaft (101) of a golf club (100) to reduce the vibration generated along the shaft (101) of a golf club (100) by a mis-hit golf shot wherein the device (10) includes: a strip (20) of elastomeric material (21) dimensioned to partially surround the shaft (101) of a golf club; a split ring clip member (30) having an expansible vertical slot (35) dimensioned to receive both the shaft of (101) of a golf club (100) and the strip (20) of elastomeric material (21); and, a capture unit (13) including a strip of adhesive tape (41) dimensioned to encircle the split ring clip member (30) at least once.

Abstract: A golf shaft having adjustable stiffness and frequency. A hollow golf shaft has a compression assembly disposed along and within the hollow shaft between the butt end and the bend point of the shaft. The compression assembly places the corresponding end of the shaft in compression and permits rapid and easy adjustment of the shaft stiffness and frequency.

Abstract: The preferred orientation, or planar oscillation plane, of a golf club shaft is located by measuring the oscillation of the shaft when an impulse is applied. Preferably, the out-of-plane oscillation is measured at a large number of angular positions about the shaft axis, and the principal planar oscillation plane is identified by that pair of opposed angular positions in which the out-of-plane oscillation is smallest. The location of the preferred orientation may be marked on the shaft and used to assemble a golf club with the planar oscillation plane in a predetermined orientation. The straightness of the shaft can also be determined by deriving its spring constant from its oscillation frequency and then measuring the restoring force when the shaft is deflected by the same nominal amount at different angular positions; differences in restoring force can be attributed to differences in actual deflection distance resulting from lack of straightness.

Abstract: A method for altering a graphite golf club shaft having a hollow interior with an interior wall surface, a butt end, and a flex zone sixteen inches from the butt end with a range one inch up and one inch down from the measured sixteen inch point which includes placing a section of steel tubing into the hollow interior shaft and against the interior wall surface in the flex zone.

Abstract: A method for altering a golf club shaft by removing less than five grams of metal from an interior wall surface in a flex zone. This is performed without penetrating through an exterior wall surface of the shaft.

Abstract: A golf club golf club having improved shock absorbing features. The golf club has a grip section, a shaft section and a head section. The shaft section has an upper end connecting to the grip section, and a lower end connecting to the head section. The shaft section further has a wave-shaped shock absorbing feature.

Abstract: The present invention relates to a golf club shaft having improved torsion characteristics comprising a base shaft having an internal surface and an external surface, and at least one wave shaped reinforced part on at least one of said surfaces, said wave shaped reinforced part comprising a plurality of reinforcement pieces. The wave shaped reinforced part is located on at least one of the upper portion, midpoint or lower portion. The golf club shafts of the present invention can be made by applying a base section of a prepreg sheet or assembly having a plurality of finger like elements to a portion of a base shaft, wrapping the finger like elements around the base shaft to provide a wave shaped reinforced part having a plurality of reinforcement pieces, and curing the shaft having the wave shaped reinforced part thereon to produce a golf club shaft having a wave shaped reinforced part.

Abstract: A vibration dampening device (10) for use on the shaft (101) of a golf club (100) to reduce the vibration generated along the shaft (101) of a golf club (100) by a mis-hit golf shot wherein the device (10) includes: a strip (20) of elastomeric material (21) dimensioned to partially surround the shaft (101) of a golf club; a split ring clip member (30) having an expansible vertical slot (35) dimensioned to receive both the shaft of (101) of a golf club (100) and the strip (20) of elastomeric material (21); and, a capture unit (13) including a strip of adhesive tape (41) dimensioned to encircle the split ring clip member (30) at least once.

Abstract: A golf club having suppressed vibration modes is disclosed. The club comprises a shaft, a golf club head, a grip and a plurality of discrete shaft stiffeners. The shaft stiffeners are strategically located along the shaft so as to shift the nodes of at least the second and third flexural vibration modes of the club shaft such that a node of each of the second and third flexural vibration modes occurs both at the club face and within the region underlying the golf club grip. Preferably, the stiffeners are made of a shape memory alloy that can be shrunk onto the outside surface of the shaft, then expanded to permit the position of the stiffeners to be adjusted to suit the boundary conditions imposed by the human user.

Abstract: The golf club of the present invention is comprised of an elongated shaft and a club head, where the club head further includes a striking face, a front toe region, a rear heel region, and opposing top and bottom edges. The elongated shaft is coupled to a hosel. Between the hosel and face there is defined a juncture region. The club also includes a small cavity, filled with a non-metallic material, which is located in the juncture region. In addition to enlarging the sweet spot of the club, the filled cavity serves to dampen or eliminate vibrations that are established in the club body as the striking face contacts a ball during the course of a typical golf swing.

Abstract: A golf shaft which features lightness, high crushing strength and high torsion strength with no interlayer peeling, as well as an excellent aesthetic design with a three-dimensional effect which gives the user a sense of depth, and a method for forming the same and a golf club using the same. The golf shaft is produced by baking a plurality of fiber prepreg layers. The shaft is a laminate comprising: a main layer of resin-impregnated high-strength high-elasticity fiber; a metal wire layer laid over the main layer; and a layer of low-elasticity fiber, laid over the metal wire layer, impregnated with resin through which the underlying metal wire layer can be seen.

Abstract: A golf club having a hollow shaft whose flexibility is determined by the tension on a wire coinciding with the shaft longitudinal axis. The is attached between a fixed assembly in the handle and a fixed assembly at the shaft lower end. The upper assembly includes a cap member, a wire-end clamping member, and a tension support member. A first embodiment uses a thin round wire. A second embodiment uses a thin tape-shaped wire.

Abstract: An variable shaft, for example for a golf club. A hollow shaft has a cable or wire in the center, and means for varying the tension of the cable or wire. Increasing tension on the cable or wire places the shaft in compression and thereby reduces its bending stiffness. Preferably, the variation means are designed so that the wire tension may be quickly and easily varied by the user.

Abstract: A vibration damper for use with a golf club having a shaft having a grip at a first end for gripping the club and a head at a second end for striking a golf ball. The grip is constructed of an elastomeric material and includes a tubular shell having a hollow interior and a cap at one end. The cap has an opening therethrough extending into the hollow interior. The vibration damper comprises an elongate element and a tuned mass. The elongate element is sized and shaped for insertion through the opening of the grip such that a first end of the element is disposed inside the hollow interior of the grip. A second end of the element opposite the first end is adjacent to and mounted on the cap of the grip. The tuned mass mounts on the first end of the element such that the mass is freely suspended within the hollow interior of the grip when the elongate element is inserted through the opening of the grip.

Abstract: A golf club shaft is formed with an elongated body using a combination of fiber-reinforced plastics and metal-coated fibers to obtain the optimally characterized golf club for a particular player. In one embodiment, a sheet-rolled or filament wound core is covered by a filament wound outer layer having at least one ply including metal-coated fibers. The fibers can be metal-coated with metals such as: nickel, titanium, platinum, zinc, copper, brass, tungsten, cobalt, gold or silver. The use of metal-coated fibers allows the use of combinations of fiber reinforced plastic and metal-coated fibers in producing golf shafts with optimum performance properties. For example, the use of metal-coated fibers allows the addition of weight to the shaft without significantly influencing its longitudinal or torsional rigidity.

Abstract: Disclosed is an iron golf club set which comprises a plurality of golf clubs of different counts, each golf club having a steel shaft, wherein a steel shaft of a shorter golf club is set heavier than that of a longer golf club; a step formation region is provided in a position having an equal distance for all of the golf clubs from a grip end in a shaft axial direction, the step formation region having a shaft outer diameter changed in a plurality of steps therein; a specific area is set in a position having an equal distance for all of the golf clubs from a sole end of a head in the shaft axial direction, and is nearer to a grip with respect to a shaft full length in the step formation region of each golf club; and a step interval in the specific area is set narrower than that outside the specific area.

Abstract: A club shaft for a golf club and method for making a club shaft for a golf club are provided herein. The club shaft includes a shaft butt section, a shaft tip section and a shaft intermediate section which connects the shaft butt section to the shaft tip section. The shaft intermediate section includes a shaft outer diameter which tapers from the shaft butt section to the shaft tip section. Uniquely, the amount of taper varies along the shaft intermediate section to avoid any abrupt transitions in the club shaft. The resulting club shaft has a continuous, smooth geometry, without stress concentration areas. This improves the strength, fatigue and fracture toughness of the club shaft. Further, the amount of taper can be specifically tailored to obtain a club shaft having the desired moment of inertia, resistance to torsion, mass distribution, flexure, frequency, strength, and stiffness properties.

Abstract: Golf clubs, golf shafts, and inserts for golf club shafts have a coil or coil-type insert for enhancing swing weight control, stiffness and flex control, shock absorption and vibration elimination or reduction. The insert has a central section and a pair of couplers integrally formed on opposite ends of the central section to attach to the shaft or club head.