US Patent 7326139 Belt with integrated monitoring

A belt has at least two fiber strands which have synthetic fiber threads twisted in themselves and are designed for acceptance of force in longitudinal direction. The strands are arranged at a spacing relative to one another along the longitudinal direction of the belt and are embedded in a belt casing. At least one of the strands comprises an electrically conductive indicator thread which is twisted together with the synthetic fiber threads of the strand, wherein the indicator thread is arranged outside the center of the fiber bundle. The indicator thread has a breaking elongation (εult,Ind) which is smaller than the breaking elongation (εult,Trag) of individual synthetic fiber threads of the strand. It can be electrically contacted so that an electrical monitoring of the integrity thereof is made possible.