The doctoral thesis deals with the problem of designing polymer gears. A model for the conversion of polymer gears with a progressively curved path of contact, i.e. S-gears, was proposed. The basis of the proposed model are the established models for the conversion of metal and polymer gears with involute tooth form. These models have been complemented in the way that they enable a reliable design of polymer S-gears. The proposed model includes a temperature control calculation and fatigue control. Fatigue control includes root and flank load carrying capacity calculation. Specific effects of S-gears that affect the operating temperature were characterized with gear testing. A large number of life time tests were performed, where the steady state operating temperature was measured. Material combinations POM/PA66, POM/POM, steel/POM, steel/PA66, steel/PEEK and steel/PA6.10 were tested. The influence of the specific tooth shape on the root and flank strength is taken into account with shape factors, which were defined by employing a series of numerical simulations. The load capacity calculation model is complemented with influencial factors, which take into account the effect of pitch and lead deviation on the stress state of the gear. Fatigue strength of tested polymer materials was determined.
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