TRACTION QUALITIES OF THE DRIVING WHEELS WHEN ROLLING THEM ALONG ONE TRACK

Abstract

During rectilinear motion of a wheeled tractor on a deformable surface, its rear wheels move along the track formed by the front ones. The amount of soil compaction can be different depending on its physical and mechanical properties, the dimensions of the front wheels of the tractor, the weight load falling on the front axle, and the like. Accordingly, the traction abilities of the rear drive wheels will also be different. This circumstance should be taken into account when designing wheeled tractors, especially tractor-tractors with two driving axles, in which a change in any of the factors listed above, for example, the distribution of the load along the axles, affects not only the compaction of the surface on which the rear wheels move, but and on the traction qualities of the front. In the course of the research, it was found that with a decrease in the load distribution coefficient below 0.5, the role of the rear wheel, which is capable of developing a greater traction force than the front wheel at the same load, in the formation of the total traction force, decreases. Therefore, the total traction force of the driving wheels becomes lower. With an increase in this coefficient above 0.5, the amount of preliminary soil compaction by the front wheel decreases; as a result, the ability of the rear wheel to develop more traction than the front wheel under the same load is reduced. The greatest traction force of two driving wheels moving along the same track is achieved with the same weight loads. Thus, the position of the center of gravity of a tractor with four driving wheels of the same size should be chosen in such a way that the load on the front and rear wheels is equalized at the rated pull on the hook. When conducting research on a field prepared for sowing, with an active semi-trailer with different load distribution between the rear axle of the tractor and the axle of the semi-trailer, it was found that the center of gravity of the active semi-trailer can be selected in the same way as for the inactive one, i.e. taking into account the influence of the semi-trailer on traction performance. The dependences obtained in the work make it possible to analyze the traction qualities of several driving wheels when they roll along one track. With their help, it is possible to identify the effect of surface compaction on the traction qualities of the rear moving front wheels; the influence of load distribution along the axles of the driving wheels on their total traction force, etc.