Abstract: A golf club putter includes a clubhead body sufficiently weighted to define a center of gravity of the golf club. The putter includes a reverse tapered shaft, preferably a graphite or fiberglass composite, elongated along a central axis continuously tapering radially inwardly, from: a larger outside diameter adjacent a tip end attached to the clubhead body, to: a smaller outside diameter adjacent a grip end. The reverse tapered shaft comprises longitudinally oriented graphite or fiberglass fibers in an arrangement that enables shaft torsional distorting forces imposed at the grip end during putting to be imparted to the clubhead and a golf ball thereby.

Abstract: A golf club putter includes a clubhead body sufficiently weighted to define a center of gravity of the golf club, which center of gravity may be adjusted for left and right handed golfers. The putter includes a graphite or fiberglass composite shaft, elongated along a central axis continuously tapering radially inwardly, from: a larger outside diameter adjacent a tip end attached to the clubhead body, to: a smaller outside diameter adjacent a grip end. Preferably, the composite shaft is reverse tapered. The reverse tapered shaft comprises longitudinally oriented graphite or fiberglass fibers in an arrangement that enables shaft torsional distorting forces imposed at the grip end during putting to be imparted to the clubhead and a golf ball thereby.

Abstract: A shaft 6 has layers. The layers include a straight layer in which an absolute angle ?a of a fiber to a shaft axis line is 10 degrees or less, a bias layer in which the angle ?a is 30 degrees or greater and 60 degrees or less, and a hoop layer in which the angle ?a is 80 degrees or greater. The layers include full length layers and a partial layer. The full length layers include full length bias layers and full length straight layers. The full length bias layers are located on the innermost side among the full length layers. The full length layer brought into contact with a low RC full length layer outside the full length bias layers is a high RC layer. The full length layer brought into contact with an outer surface of the full length bias layers is a high RC layer.

Abstract: A golf club shaft has a tip end to which a golf club head is attached and a butt end to which a grip is attached, wherein the shaft is composed of a fiber reinforced resin having a fiber layer, the fiber layer contains a bias layer having bias fibers oriented at an angle with respect to an axial direction of the shaft, the bias layer includes a tip-side bias layer extending from the tip end toward the butt end and having a butt-side end terminating without reaching the butt end and a butt-side bias layer extending from the butt end toward the tip end and having a tip-side end terminating without reaching the tip end, and bias fibers in the tip-side bias layer has a tensile elastic modulus smaller than that of bias fibers of the butt-side bias layer.

Abstract: A shaft full length is defined as Ls and a distance between a tip end of the shaft and a center of gravity G of the shaft is defined as Lg. In a shaft 6, Lg/Ls is 0.54 or greater and 0.65 or less. A shaft weight Ws is 50 g or greater and 85 g or less. The shaft 6 has at least three bias layer pairs. One bias layer pair of the three bias layer pairs is a pitch-containing bias layer pair having a pitch based carbon fiber. Two bias layer pairs of the three bias layer pairs are PAN-containing bias layer pairs having a PAN based carbon fiber. Preferably, the PAN-containing bias layer pairs are located outside and inside the pitch-containing bias layer pair.

Abstract: According to an aspect of this invention, there is provided a golf club shaft including a prepreg containing a carbon fiber, wherein the prepreg is winded and cured, and a winding thickness of the prepreg on a striking face is larger than a winding thickness of the prepreg on any other portion.

Abstract: A golf club is formed by winding and hardening a plurality of prepregs. High specific gravity materials having a higher specific gravity than carbon fiber are arranged on the butt side of the golf club. Arrangement of the high specific gravity materials is achieved by winding a high specific gravity material containing prepreg containing carbon fiber and a higher specific gravity material than the carbon fiber. Alternatively, the arrangement of the high specific gravity materials may be achieved by winding another high specific gravity material containing prepreg containing a glass fiber.

Abstract: A golf club shaft formed by winding prepregs made of uncured thermosetting resin into a tapered shape and curing the prepregs thermally, the prepregs include a first woven fabric prepreg which is made of one of a triaxial woven fabric or a tetra-axial woven fabric that are impregnated with uncured thermosetting resin, and a second woven fabric prepreg which is made of one of a triaxial woven fabric or a tetra-axial woven fabric that are impregnated with uncured thermosetting resin.

Abstract: An object is to achieve a golf club shaft and a method of producing the same, wherein the weight balance in the shaft longitudinal direction can be reproducibly and easily set and wherein the golf club shaft is produced at a low cost and has high durability. The golf club shaft includes a hollow-cylindrical shaft body made of fiber-reinforced resin and a weight-adding cylinder installed in a cylindrical space of the shaft body. At least a part of an outer diameter side of the weight-adding cylinder is embedded in an cylindrical embedded recess that is formed in an inner wall of the shaft body, wherein a grip-side cylindrical end surface of the weight-adding cylinder and a grip-side cylindrical end surface of the cylindrical embedded recess are in contact with each other.

Abstract: A golf club shaft assembly including a golf club shaft and a permanent shaft insert that is partially bonded, or is unbounded, to the golf club shaft.

Abstract: A golf club shaft and a golf club using such a golf club shaft are achieved in which the isotropy of the prepregs configuring a torsion rigidity holding layer is high and in which sufficient torsional rigidity can be secured with a lesser number of plies of prepregs. The golf club shaft is characterized by a torsional rigidity holding layer made of a thermosetting resin which contains reinforced fibers extending obliquely to a longitudinal direction of the shaft. The torsional rigidity holding layer includes a multilayer set prepreg, in which at least two layers of prepregs made of reinforced fibers are impregnated with a thermosetting resin. A plurality of prepregs in the multilayer set prepreg include reinforced fibers extending in mutually different directions; and the multilayer set prepreg is continuously wound by at least two turns with the plurality of prepregs layered on each other.

Abstract: In a shaft 6, a shaft full length is defined as Ls, and a distance between a tip end of the shaft and a center of gravity G of the shaft is defined as Lg. Lg/Ls is 0.52 or greater and 0.65 or less. A shaft weight is equal to or less than 52 g. Preferably, the shaft 6 has butt partial layers a5 and a6. When a point separated by 250 mm from a butt end Bt is defined as P2; a range from the point P2 to the butt end Bt is defined as a specific butt range; the total weight of the butt partial layers a5 and a6 existing in the specific butt range is Wa gram; and a weight of the shaft in the specific butt range is defined as Wb gram, Wa/Wb is preferably equal to or greater than 0.4.

Abstract: A golf club shaft is provided in which the flexural rigidity of the distal end portion can be improved with no change in flexural rigidity on the proximal end while the dispersion in the values of the flexural rigidity in the circumferential direction can be reduced without the use of a distal-end reinforcing layer that causes discontinuous points in the lengthwise direction in flexural rigidity.

Abstract: A golf club shaft formed by winding prepregs made of uncured thermosetting resin into a tapered shape and curing the prepregs thermally, the prepregs include a first woven fabric prepreg which is made of one of a triaxial woven fabric or a tetra-axial woven fabric that are impregnated with uncured thermosetting resin, and a second woven fabric prepreg which is made of one of a triaxial woven fabric or a tetra-axial woven fabric that are impregnated with uncured thermosetting resin.

Abstract: A golf club shaft formed by winding prepregs made of uncured thermosetting resin into a tapered shape and curing the prepregs thermally, the prepregs include a first woven fabric prepreg which is made of one of a triaxial woven fabric or a tetra-axial woven fabric that are impregnated with uncured thermosetting resin, and a second woven fabric prepreg which is made of one of a triaxial woven fabric or a tetra-axial woven fabric that are impregnated with uncured thermosetting resin.

Abstract: A device for stiffening a golf club shaft which includes a strip of material configured to engage the exterior of the golf club shaft. The longitudinal axis of the strip may be configured to extend in a direction parallel to a longitudinal axis of the golf club shaft when the strip engages the golf club shaft. The strip may be configured to increase the stiffness of a portion of the golf club shaft when the strip engages the portion of the golf club shaft. The strip may include longitudinal fibers configured to extend in a direction parallel to a longitudinal axis of the golf club shaft when the strip is engaged to the exterior of the golf club shaft. An associated method for fitting a golf club with a shaft stiffening device is also described.

Abstract: A shaft 6 has layers. The layers include a straight layer in which an absolute angle ?a of a fiber to a shaft axis line is 10 degrees or less, a bias layer in which the angle ?a is 30 degrees or greater and 60 degrees or less, and a hoop layer in which the angle ?a is 80 degrees or greater. The layers include full length layers and a partial layer. The full length layers include full length bias layers and full length straight layers. The full length bias layers are located on the innermost side among the full length layers. The full length layer brought into contact with a low RC full length layer outside the full length bias layers is a high RC layer. The full length layer brought into contact with an outer surface of the full length bias layers is a high RC layer.

Abstract: A shaft for a golf club having a total length and a total weight. The shaft includes first and second tubular portions. The first and second tubular portions are formed of first and second materials, respectively. The second tubular portion has a proximal end and a tip end. The tip end has an outside diameter of less than 0.400 inches. The distal end of the first tubular portion is co-cured to the proximal end of the second tubular portion. The shaft has a resistance to twisting about a longitudinal axis of the shaft, when tested under a torsional stability test and measured at an approximate midpoint of the total length of the shaft, of less than 2.0 degrees in a torsional stability test. The shaft when measured from the tip end of the shaft in a balance point test device has a balance point of less than 46 percent.

Abstract: A shaft set includes plural shafts used for wood-type golf clubs each having a length of 40 inches to 48 inches. Among the plural shafts, a shaft used for a longer club has a smaller amount of change ?1 in bending stiffness in a section from 600 mm to 800 mm from a tip of the shaft. Among the clubs using the plural shafts, the amount of change ?1 in bending stiffness decreases at a constant rate in a range of 0.7×103 kgf·mm2/mm·inch to 1.6×103 kgf·mm2/mm·inch per inch increase in club length, and the bending stiffness at a position 800 mm from the tip of the shaft decreases at a constant rate in a range of 0.1×106 kgf·mm2/inch to 0.4×106 kgf·mm2/inch per inch increase in club length.

Abstract: A golf club shaft is formed having a flexural rigidity layer at last one third the length of which is encased in an outer layer. The shaft is formed by applying sheets of composite material to a mandrel. Sheets forming the flexural rigidity layer include unidirectional fibers oriented substantially in parallel with the longitudinal axis of the shaft. The outer layer may include composite material sheets each having unidirectional fibers oriented at an angle with respect to the shaft's longitudinal axis. An innermost layer of the shaft may be formed of composite material sheets having fibers oriented at an angle with respect to the shaft's longitudinal axis.

Abstract: A shaft 6, which is a tubular body, includes a laminate of fiber reinforced resin layers. This fiber reinforced resin layer includes a matrix resin and a fiber. When a portion with a minimum thickness in the entire shaft is defined as a thinnest part, the entire thinnest part exists in a range of a first position to a second position. The first position is a position where an axial distance from a tip of the shaft is 50% of a full length of the shaft. The second position is a position where the axial distance from the tip of the shaft is 75% of the full length of the shaft. In this shaft 6, a flexural rigidity value EIc (N/m2) of the shaft at a point which is 175 mm away from a rear end of the shaft is two times or greater and three times or less of a flexural rigidity value EIm (N/m2) of the thinnest part.

Abstract: A shaft for a golf club is comprised of upper, central and lower sections. Flex is isolated to the central section of the club by making the upper and lower sections relatively stiffer than the central section. Though more flexible, the central section resists twisting by fabricating the section using a higher percentage of diagonally oriented fibers laid in a crossing pattern. A thickened tip and larger diameter butt end enhance resistance to twisting of the shaft.

Abstract: A graphite golf club which is formed on a mandrel is provided. The graphite golf club comprises a club head which strikes a golf ball; a club shaft which comprises a coupling unit to be coupled with the club head and a main body unit extending from the coupling unit to a golf club grip. The mandrel includes a mandrel joint unit which is formed with mandrel steps that decrease in diameter from one end of the mandrel to the other end of the mandrel. The golf club shaft is formed on the mandrel with a lower sheet layer contacting and overlapping the mandrel and an upper sheet layer overlapping an outer part of the lower sheet layer. The lower sheet layer and the upper sheet layer form a sheet joint unit which includes sheet steps decreasing in diameter corresponding to the mandrel steps.

Abstract: A precise impact and increased ball drive distance may be achieved due to an increase of elastic force and restoring force of a golf club shaft, when the golf club shaft includes: a first shell portion interiorly disposed in the golf club shaft; at least one elastic member disposed in a length direction on an exterior circumference of the first shell portion; and a second shell portion including carbon and enclosing the first shell portion and the at least one member.

Abstract: A shaft according to the present invention is obtained by winding and curing a prepreg sheet having a matrix resin and a fiber. The prepreg sheet includes a full-length sheet and a partial sheet. At least a part of the partial sheet forms a tip bias layer disposed in a tip portion of the shaft. A fiber of the first tip bias layer is oriented at an angle which is equal to or greater than 25 degrees and is equal to or smaller than 65 degrees with respect to an axis of the shaft. A fiber of the second tip bias layer is oriented at an angle which is equal to or greater than ?65 degrees and is equal to or smaller than ?25 degrees with respect to the axis of the shaft. The shaft is obtained by winding a tip bias stuck body (V1) fabricated by sticking a first tip bias sheet (a8) and a second tip bias sheet (a9) together.

Abstract: It is object of the present invention to provide a golf club shaft superior in accuracy, minimizing a displacement between thermosetting resin layers, capable of obtaining a feeling close to the feeling of a steel shaft, and superior in stability.

Abstract: By completing curing in a short period of time even at low temperatures and using an epoxy resin composition as a matrix resin of a prepreg, it is possible to obtain a fiber-reinforced composite plastic product such as a fiber-reinforced tubular composite with excellent mechanical properties and, more particularly, excellent impact resistance. The epoxy resin composition includes A component, B component, C component, D component and E component, where the content rate of sulfur atoms is equal to or more than 0.2 wt % and equal to or less than 7 wt %, and the content rate of the C component is equal to or more than 1 wt % and equal to or less than 15 wt %. A component: epoxy resins, B component: reactive products of the epoxy resins and an amine compounds including the sulfur atom in a molecule (the unreacted epoxy resins and/or the amine compounds may be included), C component: polyamide compounds soluble in the A component, D component: urea compounds, and E component: dicyandiamide.

Abstract: It is object of the present invention to provide a golf club shaft superior in accuracy, minimizing a displacement between thermosetting resin layers, capable of obtaining a feeling close to the feeling of a steel shaft, and superior in stability.

Abstract: A shaft 6 is formed by a prepreg sheet. The sheet of the shaft 6 includes full length sheets (a2), (a3), (a8) and (a11) provided wholly in a longitudinal direction of the shaft, and partial sheets (a1), (a4), (a5), (a6), (a7), (a9), (a10) and (a12) provided partially in the longitudinal direction of the shaft. The number of the full length sheets is equal to or greater than two. The number of the partial sheets is equal to or greater than four. Each of the partial sheets has an end.

Abstract: A device for stiffening a golf club shaft which includes a strip of material configured to engage the exterior of the golf club shaft. The longitudinal axis of the strip may be configured to extend in a direction parallel to a longitudinal axis of the golf club shaft when the strip engages the golf club shaft. The strip may be configured to increase the stiffness of a portion of the golf club shaft when the strip engages the portion of the golf club shaft. The strip may include longitudinal fibers configured to extend in a direction parallel to a longitudinal axis of the golf club shaft when the strip is engaged to the exterior of the golf club shaft. An associated method for fitting a golf club with a shaft stiffening device is also described.

Abstract: A golf club shaft has a function of attenuating the vibration of the shaft at the time of impact and also having a function of stabilizing the struck ball. A shaft has an inner bias layer having a fiber direction that was inclined with respect the shaft axial direction and an outer bias layer having a fiber direction that is inclined with respect to the shaft axial direction in a direction opposite from that of the inner bias layer laminated as a fiber-reinforced resin layer, and a vibration-damping material sheet layer having a vertical-direction length of about 110 mm to about 150 mm disposed between the inner bias layer and the outer bias layer, with region of the position of the end of the grip attachment location as the rear end in the vertical direction.

Abstract: Construction and advantages of improved wavy composite structures made from wavy composite, unidirectional composites, and damping materials is revealed. By combining wavy composite laminae in various waveforms, offsets, angular orientations and material combinations, it is possible to provide axial, torsion, or shear properties equivalent to unidirectional materials but without the limitations related to fiber discontinuity, labor costs for fabrication, and weakness at seams where laminates overlap. By combining wavy composite layers with unidirectional crossplies, or by using woven mats with various fill fiber levels where the warp fibers are sinuously arranged, improved strength and damping is possible. Several examples of both wavy crossply laminates and unidirectional crossply laminates are analyzed and compared.

Abstract: A golf club shaft is provided that has a grip end opposite a head end and defining a length of the shaft extending between those two ends. The shaft has a tubular cross-section over at least one portion of the shaft length which cross-section has a substantially circular outer periphery and a polygon inner periphery formed of a plurality of between 4 and 24 flats, and preferably formed of 8-16 flats. A mandrel having the shape of the inner periphery of the shaft is also provided, as is a method of forming the shaft that uses the mandrel and composite matrix materials.

Abstract: It is a sport equipment 2 using a partially hardened sheet form prepreg 10 formed by impregnating a reinforced fiber material 6 disposed substantially parallel with a thermal hardening resin material 7 to bind the reinforced fiber material, where the prepreg is layered so as to form a tube rod in a tapered shape having a diameter increasing from one end to the other, and the tube rod is provided with a strengthening means on a radially entire circumference to the axis direction. Herewith it is especially used for a golf club shaft, while maintaining a characteristic of light weight, securing strength equal to or greater than a steel-made golf shaft, and suppressing unnecessary deflection and vibration, so as to provide a sports equipment made of a reinforced fiber combined material such as a gold club shaft having high strength such as bending and twisting rigidity.

Abstract: A shaft for a golf club comprises a plurality of fiber-reinforced resin layers. A plurality of circumferentially oriented metal wires are provided at intervals of 1 mm to 4 mm in an axial direction of the shaft having a length in an axial direction of more than 100 mm and less than 300 mm and being centered at a position of 3.25×102 mm from a larger-diameter end of the shaft.

Abstract: A shaft for a golf club having a total length and a total weight. The shaft includes first and second tubular portions. The first and second tubular portions are formed of first and second materials, respectively. The second tubular portion has a proximal end and a tip end. The tip end has an outside diameter of less than 0.400 inches. The distal end of the first tubular portion is co-cured to the proximal end of the second tubular portion. The shaft has a resistance to twisting about a longitudinal axis of the shaft, when tested under a torsional stability test and measured at an approximate midpoint of the total length of the shaft, of less than 2.0 degrees in a torsional stability test. The shaft when measured from the tip end of the shaft in a balance point test device has a balance point of less than 46 percent.

Abstract: A shaft 6 includes a textile layer. The textile layer has a biaxial textile 20 composed of warps and wefts. The warp is oriented substantially parallel to an axial direction of the shaft. The weft is oriented substantially perpendicularly to the axial direction of the shaft. When a tensile elastic modulus of the warp is defined as ET (tf/mm2) and a tensile elastic modulus of the weft is defined as EY (tf/mm2), the tensile elastic modulus ET is smaller than the tensile elastic modulus EY. Preferably, the warp is a PAN carbon fiber and the weft is a pitch carbon fiber. Preferably, when a tensile strength of the warp is defined as ST (kgf/mm2) and a tensile strength of the weft is defined as SY (kgf/mm2), the tensile strength ST is greater than the tensile strength SY.

Abstract: A shaft of the present invention has a tip reinforcing layer. A prepreg s9 for the tip reinforcing layer has a portion having a larger circumferential direction width Ws toward a tip side. The prepreg s9 for the tip reinforcing layer has a thickness Pt of 0.06 mm or greater and 0.12 mm or less. An edge Ds of the tip reinforcing layer extends in an axial direction of the shaft while circulating in a circumferential direction of the shaft. When a height h1 of the edge Ds at a position placed apart from a tip by 60 mm is defined as h11; the height h1 at a position placed apart from the tip by 120 mm is defined as h12; the height h1 at a position placed apart from the tip by 180 mm is defined as h13; the height h1 at a position placed apart from the tip by 240 mm is defined as h14; and the height h1 at a position placed apart from the tip by 300 mm is defined as H15, an average value Ha of the five heights h11 to h15 is equal to or less than 0.03 mm.

Abstract: A golf club shaft has a more attractive appearance than a coating of plating and also achieves a rustproofing effect within the shaft, while avoiding the problem of an increase in weight and processing of effluents associated with plated shafts. The golf club shaft has a shaft body, a covering film formed by chemical treatment of an outside surface and an inside surface of the shaft body, a coating film layer formed by electric painting on the covering film of at least the outside surface; and a pigment layer, in which a polarizing powder is dispersed, which is coated on the coating film layer.

Abstract: A golf club shaft (10) having a weight not less than 30 g nor more than 60 g. The golf club shaft (10) includes a bias layer (B1) composed of a prepreg whose reinforcing fibers have an orientation angle of not less than ±10° nor more than 80° to an axis of the golf club shaft (10) and a straight layers (A1 through A6) each composed of a prepreg whose reinforcing fibers have an orientation angle within 0°±10° to the axis of the golf club shaft (10). At least one partial reinforcing hoop layer whose reinforcing fibers have an orientation angle of within 90°±10° to the axis of the golf club shaft (10) is disposed in only an important reinforcing region in a range from a point (P) spaced at 15% of a full length (L) of the golf club shaft (10) from a grip-side butt (12) thereof to a point (Q) spaced at 45% of the full length (L) of the golf club shaft (10) from the grip-side butt (12) thereof.

Abstract: A golf club shaft is provided in which the flexural rigidity of the distal end portion can be improved with no change in flexural rigidity on the proximal end while the dispersion in the values of the flexural rigidity in the circumferential direction can be reduced without the use of a distal-end reinforcing layer that causes discontinuous points in the lengthwise direction in flexural rigidity.

Abstract: A composite golf club shaft having a reinforcing ribbon of composite material spiraling along an intermediate portion of the shaft and bonded thereto to reinforce the hoop strength of the shaft. The ribbon is shaped into a rib of different cross-sectional shapes, the preferred embodiment being a thin rectangular shape approximately 0.125 wide of an inch and spiraling at a rate of four turns per inch, producing a groove of equal width. The methods of the invention produces the shaft by providing a mandrel having the outside shape desired for the shaft's inside surface; wrapping a ribbon of reinforcing material around the shaft in a spiral groove therein; forming the shaft body around the mandrel; and separating the mandrel from the shaft after curing, by unscrewing the mandrel.

Abstract: A golf club head includes a club head body having a striking face, a soleplate, a crown, a toe, a heel and a hosel shaped and dimensioned for receiving a shaft. The club head body includes a body shell composed of the striking face, soleplate, crown, toe and heel, wherein the body shell has a reduced mass allowing for greater weight manipulation within the club head body.

Abstract: The method of producing tubular golf club shafts (10) of the same longitudinal stiffness and varying weights by wrapping composite materials on a tapered mandrel (15), or mandrels, having a given taper profile, producing a core (30) of angle-fiber-and-resin material and a shell (31) of longitudinal-fiber-and-resin material, and varying the weight of the cores to vary the shaft weight while maintaining the core size and the shell size the same. This is accomplished by moving the core along a taper profile to compensate for the change in the amount of material, thus maintaining the longitudinal stiffness/bending profile the same in the shafts of greatly varying weight. A representative family of shafts (10) has nominal weights of 55, 65, 75, 85, 95 and 105 grams, with the same stiffness/bending profile.

Abstract: A shaft set includes plural shafts used for wood-type golf clubs each having a length of 40 inches to 48 inches. Among the plural shafts, a shaft used for a longer club has a smaller amount of change ?1 in bending stiffness in a section from 600 mm to 800 mm from a tip of the shaft. Among the clubs using the plural shafts, the amount of change ?1 in bending stiffness decreases at a constant rate in a range of 0.7×103 kgf·mm2/mm·inch to 1.6×103 kgf·mm2/mm·inch per inch increase in club length, and the bending stiffness at a position 800 mm from the tip of the shaft decreases at a constant rate in a range of 0.1×106 kgf·mm2/inch to 0.4×106 kgf·mm2/inch per inch increase in club length.

Abstract: A golf club shaft wherein the flexibility of the club over a short segment at the butt or grip end is increased in a controlled manner. A flexible tubular shaft insert of approximately 7 to 10 inches in total length having a tapered portion of approximately 2 to 3 inches in length and of increased diameter, the outer diameter of the tapered portion being sized and configured so as to mate with the inner diameter of the actual golf club shaft, is inserted into the shaft. A flexible sleeve is disposed about the exposed extension portion of the tubular shaft insert, the outer diameter of the flexible sleeve approximating the outer diameter of the golf club shaft, such that a standard grip may be applied over the butt end of the shaft and the extended portion of the shaft insert.

Abstract: A golf club shaft 2 made of a fiber-reinforced resin having a weight W of 30 to 55 g calculated as a shaft having a length of 46 inches and an average flexural rigidity EIa of 1.5 to 4.0 kgf·m2 and satisfying the equation: EIa?0.1W?1.5. Since it is light weight but has a relatively high flexural rigidity, a golf club can be swung at high speed without deteriorating the flight direction performance.

Abstract: A golf club shaft having at least six full-length layers composed of prepregs. The full-length layers are divided into an inner-layer part including a half of the full-length layers and an outer-layer part including a remaining half of the full-length layers. At least one pair of the full-length layers is formed as a bias set layer in each of the inner-layer part and the outer-layer part by layering two bias layers with each other, with reinforcing fibers of the bias layers intersecting with each other at an orientation angle of ±?° which fall in a range from ±25° to ±65° with respect to an axis of the golf club shaft. A straight layer is formed as an outermost full-length layer of the outer-layer part with reinforcing fiber thereof orienting at the range from 0° to ±10° with respect to the axis of the shaft.

Abstract: A golf club shaft formed by winding prepregs made of uncured thermosetting resin into a tapered shape and curing the prepregs thermally, the prepregs include a first woven fabric prepreg which is made of one of a triaxial woven fabric or a tetra-axial woven fabric that are impregnated with uncured thermosetting resin, and a second woven fabric prepreg which is made of one of a triaxial woven fabric or a tetra-axial woven fabric that are impregnated with uncured thermosetting resin.

Abstract: A shaft 6, which is a tubular body, includes a laminate of fiber reinforced resin layers. This fiber reinforced resin layer includes a matrix resin and a fiber. When a portion with a minimum thickness in the entire shaft is defined as a thinnest part, the entire thinnest part exists in a range of a first position to a second position. The first position is a position where an axial distance from a tip of the shaft is 50% of a full length of the shaft. The second position is a position where the axial distance from the tip of the shaft is 75% of the full length of the shaft. In this shaft 6, a flexural rigidity value EIc (N/m2) of the shaft at a point which is 175 mm away from a rear end of the shaft is two times or greater and three times or less of a flexural rigidity value EIm (N/m2) of the thinnest part.