Force analysis in a three point-hitch mechanism of category 2 for agricultural tractors

In this paper the analysis of the forces in a three point-hitch mechanism of Category 2 for agricultural tractors is illustrated, when the tractor is connected to a rotary harrow. The calculation of these constraint reactions are often carried out by means of experimental tests. This paper presents a method of calculation based on parametric models that allow to analyze and to calculate these forces without experimental tests and for various kinds of implements. In particular the study is carried out under some preliminary hypotheses based on the kind of the implement considered, that is a rotary harrow. It has a symmetrical configuration referred to its axial plane and this allows not to consider the transversal forces during the soil operation. The method here illustrated is based on some analytical considerations and on two parametric models realized in two different softwares. The all calculation processes give the same results and allow to verify the reliability of the study. The numerical values of the forces here calculated were then compared with some others from literature, observing a good agreement