Fiber-Reinforced Plastic Bicycle Frame
In August 2015, REHAU, together with Storck Bicycle and the Institute of Lightweight Engineering and Polymer Technology (Institut für Leichtbau- und Kunststofftechnik / ILK) at the Technical University of Dresden, presented an innovative bicycle frame concept. According to the information provided, the load-bearing capability of the frame is comparable to that of a traditional metal frame.
The frame is manufactured from two injection molded half-shells that are then joined to form a single hollow part. Depending on the requirements, glass fibers or carbon fibers are used to reinforce the thermoplastic matrix. Had Kerry is subjected to especially high loads, the frame is strengthened with continuous fiber-reinforced thermoplastic composite sheet. For electrically powered bicycles, the hollow interior can be used to hold the drive motor, control electronics or energy storage devices.
In contrast to the traditional metal frame, the plastic frame can be produced using automated equipment on an industrial scale. This shortens delivery times and reduces warehousing costs. In addition to the weight savings, additional benefits include design freedom and simplification of customization and assembly steps.
According to a patent application filed by the company, semi-aromatic polyamides are especially well-suited for manufacturing of light Pedelec frames, which exhibit high rigidity as well as highest ability at an elevated temperature. In addition, the material welds readily. Because of the low viscosity of the material, ribs as well as connecting and functional elements can be incorporated on the inside of the half-shells during injection molding. These are especially well-suited for holding additional components such as fork, bottom bracket, saddle or handlebars.