Losses represent a major problem in all areas, including the development of electric motors. Customers always want to have electric motors with better efficiency, therefore reducing losses has become one of the main tasks of motor designers.
This thesis presents losses in the universal commutator motor which is used for dry suction vacuum cleaners, with an emphasis on the measurement of mechanical losses. Methods for determination of mechanical losses are presented and analysed. Laboratory mesurement were provided to evaluate mechanical losses. On this basis a new design of motors with higher efficency can be made.