Abstract: A game racket frame of fiber reinforced plastic consists of a head formed of an oval main body which is composed of a first inner tube, a second inner tube, and an outer tube. The inner tubes are arranged side by side in the direction toward the head face of the game racket such that the adjoining walls of the inner tubes are attached for forming cross ribs in the main body, and that the outer walls of the inner tubes are intimately attached to the inner wall of the outer tube. The interior of the main body is provided with the cavities of the inner tubes. The main body is further provided with a plurality of string holes extending through the main body in the direction toward the head face of the game racket. The sideway structural strength of the main body is thus reinforced by the cross ribs formed at the junctions of the laminated inner tubes.

Abstract: A badminton racket is composed of an oval frame, a grip, and a shaft fastened between the oval frame and the grip. The shaft has a shell which is formed of a plurality of fiber-reinforced plastic layers and at least one metal gauze layer. The metal gauze layer is formed of a first metal filament and a second metal filament such that the first metal filament is extended in a direction forming an angle with the longitudinal axis of the shaft, and that the second metal filament is extended in a direction forming an angle with the longitudinal axis of the shaft. The angles so formed are preferably 60 degrees each.

Abstract: A composite-metal wood-style golf club head having a metal casing with at least two openings in the crown in which composite covers are disposed. The portion of the metal casing between the covers defines a bar-like stiffener that extends between the face and the back in a direction generally perpendicular to the face. The metal stiffener braces and reinforces the face against flexure during impact with the ball, while the composite covers optimize weight distribution and provide other advantages. The club head may include a composite core with a relative thick portion behind the hitting face to further reinforce the hitting face against flexure.

Abstract: An apparatus for preforming a main body of a racket frame from a softened fiber reinforced thermoplastic resin composite tube includes an inner mold which has a base with a flat face that has an X axis and a Y axis perpendicular to the X axis. The inner mold further has a protrusion projecting from the flat face. The protrusion has an outer periphery which conforms with a contour of a racket frame and which confines a head-like portion and a shaft-like portion along the Y axis. A pressing unit for pressing the composite tube against the outer periphery includes a frame reciprocatable along the Y axis by means of a driving unit, two support members disposed opposite to each other and fixed respectively to the movable frame, two rolls mounted respectively to the support members, and a biasing unit for biasing each roll to press the composite tube against the outer periphery. An outer mold has two opposite halves disposed on two sides of the inner mold and movable along the X axis by means of a moving unit.

Abstract: A method for producing a composite golf club head includes the steps of forming a metal hollow casing; disposing a bowl-shaped laminated member in the metal hollow casing; providing an expansible pocket in the bowl-shaped laminated member, the expansible pocket containing a mixture of sodium nitrite, ammonium chloride and water; disposing a sheet of carbon fiber composite material over an open top portion of the metal hollow casing, in order to close the open top portion of the metal hollow casing and the open end of the bowl-shaped laminated member; disposing the metal hollow casing in a mold; and heating the mold to a temperature of 140.degree.-160.degree. C.

Abstract: A method for manufacturing the shaft unit of a golf club includes the following steps: (1) providing a shaft which has a first end surface, a second end surface, and a cross-sectional area that increases gradually from the first end surface to the second end surface; (2) providing an elongated first-layer sheet which is made of resin, and which has two inclined end surfaces that are parallel to each other and several fibers that are evenly coated on the sheet that extend along the length of the sheet; (3) winding the sheet on the shaft in a clockwise direction from the first end surface to the second end surface of the shaft in such a manner that one of the end surfaces of the sheet and the first end surface of the shaft are on a similar plane and that the fibers of the sheet form an angle of about 48.+-.3 degrees with respect to an axis of the shaft so that, when the first-layer sheet is wound to the second end surface of the shaft, the fibers of the first-layer sheet form an angle of about 19.+-.

Abstract: A composite golf head includes a head portion which is made of a carbon fiber composite material. The head portion has a front face, a rear face opposed to the front face, a top face, and a bottom face opposed to the top face. A metal reinforcing plate is fixed to the front face. The metal reinforcing plate has an upper extension fixed to a first part of the top portion. The metal reinforcing plate has a lower extension fixed to and wrapping around the bottom face and the rear face and extending to a second part of the top face.

Abstract: A composite golf head includes a head portion with a striking face, and a striking plate fixed to the striking face of the head portion. The head portion is made of a carbon fiber composite material and the striking plate is made of a wear resistant material. A plurality of first projections extending outwardly from the peripheral edge are adjacent to the inside face of the striking plate. Between each of the first projections and its peripheral edge a shoulder portion is formed. The head portion has a plurality of engaging grooves formed therein which are adjacent to the striking face of the head portion so that the first projections can be received and locked in their respective engaging grooves.

Abstract: A method of producing a connecting tube that interconnects the shaft and the handle of a racket includes the steps of performing two foamed preforms which cooperatively form a foamed layer; placing the two foamed preforms around an internal impregnated fiber wall of the connecting tube; wrapping predetermined layers of impregnated fibers around the two preforms to form an external impregnated fiber wall; and heating the internal and external impregnated fiber walls and the preforms in a mold to allow the internal and external impregnated fiber walls and the preforms to connect integrally.

Abstract: In a golf club, the neck between the shaft and the head is strengthened by integrally forming the head and the shaft in a single mold so that the golf club is a one piece molded body. Alternatively, a separate shaft and head can be joined to one another and the joint formed therebetween is wrapped around with a resin impregnated fibrous material which will then be cohesively bonded to the shaft and the head after application of heat.

Abstract: The golf club head includes a hollow main body that is made of metal and has a front side with a wall that defines a cavity at an outer surface. A projection unit is formed integrally with the periphery of the wall at an inner surface of the latter and extends into the hollow main body.

Abstract: A golf club head has a metal main body with a toe, a heel, a front hitting portion which widens gradually from the heel to the toe, a rear portion opposite to the front hitting portion and formed with a cavity and an annular groove which is disposed around the cavity, and a sole portion which extends between the toe and the heel at lower ends of the front and rear portions. The main body is formed with a curved peripheral groove of predetermined width which extends from the front hitting portion to the rear portion and which is formed adjacent to the heel. The peripheral groove is communicated with the cavity and the annular groove and has two ends which terminate adjacent to the sole portion. The main body further has a hosel with a diameter reduced portion which extends obliquely upward from the heel. A layer of carbon fiber reinforced resin material is provided around the diameter reduced portion and extends into the peripheral groove.

Abstract: A metal racket includes a hollow looped head portion having a cross-section lying on a plane perpendicular to a string web held by the looped head portion. The cross-section includes a convex outer periphery with two terminating ends disposed on opposite sides of the string web, a first axis perpendicular to the string web and passing through the terminating ends of the outer periphery, and an inner periphery opposite to the outer periphery and having two flat portions extending inwardly from a respective terminating end of the outer periphery and disposed along the first axis. The inner periphery further has an inner convex portion disposed between and interconnecting the flat portions. The cross-section has an axis of symmetry extending along the string web and perpendicular to the first axis. The axis of symmetry passes through a first point on the inner convex portion. The outer periphery has a central portion divided by the axis of symmetry at a second point.

Abstract: A method for manufacturing a racket frame includes the steps of making a metal part having at least one joint end formed with a groove; covering the joint end of the metal part with a layer containing glass fibers to serve as an electrical insulating layer; making a preformed plastic part by wrapping a resin saturated carbon fiber material around a tube unit and by providing at least one end portion in the tube unit which has a wrapping layer thinner than that of the remaining portion of the tube unit to serve as a joint end; folding the end portion of the tube unit to seal the tube unit; inserting the folded end portion of the tube unit into the groove; wrapping and fastening the joint end of the metal part and the plastic part adjacent to the joint end of the tube unit with a resin saturated carbon fiber layer; forming and heating the metal part and the preformed plastic part in a mold; and supplying a compressed air into the tube unit to create a predetermined pressurizing force during the forming and heat

Abstract: A head of a golf club includes a hollow body which has a bottom side and a recess formed at the bottom side; an adhesive material; a weight received in the recess, the adhesive material provided in the recess and surrounding the weight for adhering and fixing the weight in the recess; a screw member having a shank; and a bottom cover with a hole, the cover being secured to the bottom side to cover the weight by the shank of the screw member passing upwardly through the hole of the bottom cover into the recess and adhering to the adhesive material.

Abstract: A bicycle member for mounting a braking device to a rear fork of a bicycle, the fork having a pair of tubular tines, each made of a composite plastic material, at least one of the tines having a mounting hole. The bicycle member includes a metal member, at least a part of which is adapted to be disposed within the mounting hole. The metal member has a resin impregnated fibrous material wrapped around it so that the fibrous material is disposed between the metal member and the one tine.