Dimenzování páky řízení nákladního automobilu

Abstract

This doctorate thesis is concerned with conceptual suggestions for the process of designing lever steering systems solutions which are components designed to be of the highest safety. Because new forms of lever steering for contemporary types of vehicles are being constantly developed, as are changes in their design, every new type must undergo appropriate examinations. This thesis describes two design variations of levers and the effectual strength calculations of these levers in critical places with the maximum load stress, which leads to an examination of the appearance of cracks and faults. Classic strength calculations are then methodically compared with the achieved results of strain on final components. The resulting assessment is then given of worn out levers achieved using simple calculations compared with results achieved by exhaustive examinations carried out in the Tatra Company. Calculations are further provided of the life span for some types of the considered spectrum, which were chosen from operational examinations of pull steering on different polygon routes at the Tatra Company. The life span is calculated according to a computer programme which includes calculations based on the four most used theories of linear accumulation of fatigue damage (Palmgren-Miner, Corten-Dolan, a Haibach). The resulting evaluation of the bearing capacity from the safety point of view, fatigue limits and calculations of the life span on different polygon routes and prediction of the life span in standard traffics of lorries is provided.