Engineering design of polymer gears with S form of teeth

V doktorskem delu je obravnavana problematika konstruiranja polimernih zobnikov. Predlagan je model za preračun polimernih zobnikov s progresivno ukrivljeno ubirnico, t. i. S-ozobjem. Pri postavitvi modela za S-ozobje smo izhajali iz uveljavljenih modelov za preračun kovinskih in polimernih zobnikov z evolventnim ozobjem. Ti modeli so bili dopolnjeni tako, da omogočajo dimenzioniranje zobnikov s S-ozobjem. Model zajema kontrolni preračun temperature pri obratovanju in kontrolo korenske in bočne trdnosti. Specifični vplivi oblike S-ozobja na temperaturo pri obratovanju so bili okarakterizirani s preizkušanjem zobniških dvojic. Izvedenih je bilo večje število trajnostnih preizkusov polimernih zobniških dvojic, kjer smo merili temperaturo v ustaljenem stanju. Testirane materialne kombinacije pogonskega in gnanega zobnika so bile POM/PA66, POM/POM, jeklo/POM, jeklo/PA66, jeklo/PEEK in jeklo/PA6.10. Vpliv specifične oblike profila zoba na korensko in bočno trdnost je v modelu za dimenzioniranje upoštevan z vplivnimi koeficienti, ki so bili določeni s pomočjo sistematičnega izvajanja numeričnih simulacij. Model za trdnostni preračun je dopolnjen s koeficienti, ki upoštevajo vpliv izdelovalnih natančnosti razdelka in bočne slednice, na napetostno stanje v zobniku. Določena je bila tudi dinamična korenska trdnost za testirane polimerne materiale.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