Method of manufacturing a tennis racket
Patent 4264389 Issued on April 28, 1981. Estimated Expiration Date: 
January 15, 2000. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
January 15, 2000. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3483055 3755037 Process of manufacturing tennis racket frames or the like Laminated fiberglass tennis racket Method for preparing a composite high strength to weight structure with fray resistance Tennis racket manufacture Patent #: 4183776 InventorsAssigneeApplicationNo. 06/112380 filed on 01/15/1980US Classes:156/156, With fluid pressure to prevent collapse of hollow structure during assembly and/or joining156/245, In configured mold156/253, Subsequent to assembly of laminae264/258, Joining a plurality of superposed fibrous or textile layers264/314, Utilizing fluid-expansible mold473/535, Fiber reinforced plastic frame473/539Elongated string-hole liner (e.g., grommet, bushing, etc.)ExaminersPrimary: Ball, Michael W.Attorney, Agent or FirmInternational ClassesA63B 49/02 (20060101)A63B 49/08 (20060101) A63B 49/00 (20060101) A63B 49/10 (20060101) AbstractA tennis racket frame is constructed primarily of an elongated tubular member having a wall thereof consisting of a plurality of concentric layers of high tensile strength fibers impregnated and bonded together by binder resin to produce a hollow cored tennis racket. The method includes forming a plurality of string holes in the head portion of the racket, during or prior to the molding operation. The holes are formed by separating the fibers around the location of the hole by passing pointed penetrating tools through the frame in the area which will form the head portion thereof, and either retaining the tool in position in the holes during molding, or replacing the tools with positioning pins or grommets prior to the molding operation. If the pins are utilized they may be removed after molding of the racket is complete, and if grommets are utilized they become integrally attached to the racket and provide additional support for the strings.Field of SearchWith fluid pressure to prevent collapse of hollow structure during assembly and/or joiningWith winding of separate sheet or web Winding about and uniting to core Winding about subsequently removed core or mandrel Sequential winding of separate webs About irregular or configured mandrel surface With additional assembly (other than winding) In configured mold Subsequent to assembly of laminae | |
