1 research outputs found
Utjecaj triboloŔkih procesa mehanizma slobodnog hoda na radne karakteristike impulsnih tarnih varijatora
The impulsive friction variators are very specific transmitters. They are characterised by the periodical impulse transmission of power and motion. For research purposes, the device was made to simulate wear of the tribomechanical system: external envelope (coulisse) ā roller and roller-shaft in the free motion mechanism with use of the impulsive friction variators. Monitoring of the elements of tribomechanical system was conducted by recording the changes of dimensions depending on the investigation time. Roughness parameters were measured and wear traces of the tribomechanical system were recorded. It was concluded that at the shaft (star), a dominant mechanism of wear is pitting, and that destruction of the oil film precedes the damage at the coulisse (roller). By analysing the change of the gap and influence of the change of wedging angle, it is determined that the period of intensive wear at the beginning and the period of constant wear can be differentiated. It was concluded that the change of the gap clearly represents theImpulsni tarni varijatori su vrlo specifiÄni prijenosnici. Karakterizira ih impulsni periodiÄni prijenos snage i gibanja. U cilju istraživanja izraÄen je ispitni ureÄaj za simuliranje troÅ”enja tribosustava: vanjski prsten (kulisa) - valjÄiÄ i vratilo - valjÄiÄ u mehanizmu slobodnog hoda pri radu impulsnih tarnih varijatora. PraÄenje elemenata tribosustava vrÅ”eno je snimanjem promjena dimenzija u ovisnosti o trajanju ispitivanja. Mjereni su parametri hrapavosti i snimani tragovi troÅ”enja elemenata tribosustava. ZakljuÄeno je da je kod vratila (zvijezde) dominantni mehanizam troÅ”enja pitting, a da oÅ”teÄenju vanjskog prstena (valjÄiÄa) prethodi razaranje uljnog filma. Analizom promjene zazora i utjecaja promjene kuta zaklinjavanja utvrÄeno je da se mogu razluÄiti period poÄetnog intenzivnog troÅ”enja i period ustaljenog troÅ”enja. ZakljuÄeno je da promjena zazora jasno prikazuje krivulje troÅ”enja triboelemenata. PoveÄanje zazora direktno utjeÄe na promjenu kuta zaklinjavanja, a samim time i na poveÄanje neravnomjernosti rotacije izlaznog vratila