Abstract Racket having frame including an oval head portion and a handle portion integrally formed by a tubular member composed of helically wound fibers of high tensile strength embedded in a hardened binder and having a pre-formed reinforcing member defining the base of the oval head portion and bonded on opposite sides to the tubular member, the handle portion being defined in part by generally parallel extending portions of the tubular member surrounded by a grip. Method of making a tubular article by helically winding high tensile strength fibers about a core provided with a substantially fluid tight casing; the core is removed and the wound casing is placed in a mold, a binder for the fibers is added, the interior of the casing is supplied with fluid under pressure, and the binder is hardened.
A method of making a racket frame comprising the steps of: a. providing a core which is substantially rigid in a radial direction; b. covering said core with a flexible, fluid-tight casing; c. placing said core under axial tension; d. helically winding a plurality of layers of a strip of material about said core and casing to form a flexible, tubular member; e. impregnating said material with a hardenable binder; f. releasing said core from said axial tension; g. placing said tubular member in a mold having a cavity defining a racket shape; h. applying fluid under pressure to the interior of said casing; i. removing said core from said casing after said helical winding step and before applying fluid under pressure thereto; and j. hardening said binder.
Claim 2
Independent Claim
128 words
A method of making a racket frame comprising the steps of: a. providing a core which is substantially rigid in a radial direction; b. covering said core with a flexible, fluid-tight casing; c. placing said core under axial tension; d. helically winding a plurality of layers of a strip of material about said core and casing to form a flexible, tubular member; e. impregnating said material with a hardenable binder; f. releasing said core from said axial tension; g. placing said tubular member in a mold having a cavity defining a racket shape; h. applying fluid under pressure to the interior of said casing; i. removing said core from said casing after said helical winding step and before applying fluid under pressure thereto; and j. hardening said binder.
Claim 3
Dependent Claim
12 words
The method claimed in claim 1 wherein said core is axially flexible.
Claim 4
Dependent Claim
18 words
The method claimed in claim 1 wherein said helical winding includes at least two helixes of opposite hand.
Claim 5
Dependent Claim
34 words
The method claimed in claim 1 including the steps of providing longitudinal reinforcing fibers for at least the head portion of said racket frame, and bonding said reinforcing fibers to said helically wound material.