Manufacture of bicycle frames

Abstract

In a bicycle frame comprising a plurality of frame members which are selectively joined together at the ends thereof, each of the joints which support the head tube, the seat and the crank housing is a lug joint comprising a plurality of organic fiber layers partially wrapping the joined end portions of the frame members, the fibers composing each layer being oriented at different angles from the fibers in the adjacent layers, and all of these sheets being impregnated with resin which hardens to secure the sheets to the frame members. Web portions of these fiber layers also enclose a portion of the space between wrapped portions of the frame members, and each of these spaces is filled with a suspension of microballoons in hardended resin which cooperates with the web portions of the fibers layers to brace the joined frame members against movement toward each other during use of the bicycle. The production of bicycle frame in accordance with the invention is expedited by utilizing, as the resin component of each joint, a two-part resin which sets by exothermic reaction at room temperature and thus eleminates need for heat treatments such as are required in the case of thermosetting resins, brazing and other such manufacturing procedures.

Dependencies are inferred from the claim text.