Theoretical substantiation of parameters of rotary subsoil loosener

In recent years, many researchers have paid more attention to the substantiation and determination of the range of optimal (rational) parameters, ensuring a reduction in energy, labor and time, and the effect of mechanical treatment on the soil structure. The article presents the rationale and determination of the design parameters of the rotary subsoil loosener of the combined plough for flat ploughing. Rotational working element is made in the form of a screw cone mounted on a bearing, with the possibility of frictional rotational movement around its own axis from the reaction of the soil, and which is a multiple-thread screw. Oscillatory-rotational movement, which occurs in the process of introducing the ripper-subsoiler into the soil, is due to the uneven resistance of the soil. An analytical study was conducted from the point of view of the impact of soil-cultivating workers on the soil, depending on their design parameters. Analytical dependences of the subsoil loosener were obtained, which allowed substantiating the choice of its design parameters, in particular, the central angle β at the top of the cone, the width of the grip, the distance L between the plough bottoms and the resistant subsoil loosener, and the length of the soil splitting. Central angle at the cone apex β depends on the depth at which loosening occurs, the extension length of the cone apex from the tine and the rear cutting angle of the subsoil loosener.Minimal acceptable distance from the subsoil loosener’s tine to the combined tillage machine’s bottom depends on the depth of loosening, rear cutting angle, cone apex angle β and the physical-mechanical properties of the soil. These dependences determine the possibility of a stable rotational workflow, which is reduced to a constructive implementation after the calculation of its basic parameters. The obtained analytical dependences and some prerequisites can be used both in the study and in the design of such rotary working bodies.