US Patent 7354366 Toothed belt

A toothed belt for the transmission of force is provided, a polyurethane body forms an outer layer and may be fabric-reinforced. Teeth of polyurethane are formed on the polyurethane body as an inner layer. High-strength tension elements are disposed between the outer layer and the teeth and are formed of spirally wound, spaced-apart cord filaments. A material layer of wear-resistant material covers the inner peripheral surface of the belt and hence the teeth. The cord filaments can be comprised of polyester-polyacrylate fibers/filaments produced by fusion spinning from liquid crystal polymers, and PBO fibers/filaments. Alternatively, the cord filaments can be comprised of hybrid filaments of high-strength aramid fibers and elastic polyamide fibers, or the hybrid filaments can have a high-strength filament component and a dampening or elastic filament component.