Substantiation of the main parameters of stability of the packing wheel of a sowing unit

Abstract

Improving the technology of cereal crop sowing into stubble using a tine coulter is a topical issue. In this regard, special attention should be paid to wide-span sowing units as the Kuzbass sowing unit. Nowadays, tine coulters are increasingly used in seed drills with gravity seeding and with pneumatic seed transportation in wide-span sowing units. Of the trailed seeders for sowing cereal crops, the most widespread are stubble drills SKP-2.1 and SZS-2.1 and the Kuzbass sowing units which have five modifications in terms of operating width (PK-6.1; PK-8.5; PK-9.7; PK-12.2; PK-15.8). The sowing section developed at the Chair of Agricultural Machinery and Technologies is designed for sowing cereal and legume crops; it includes a tine coulter, a seed dispenser, a chisel and a packing wheel. This paper describes the working process of the sowing section and substantiates the stability parameters of the packing wheel. During the operation of the sowing section, the entire system of solid bodies is in a state of absolute and relative motion. The pattern of the sowing section movement is determined by the forces acting on it. These forces are represented in the calculation scheme. A characteristic feature of the seeder operation is that in order to carry out the technological process, the working tools should move across a field that is not uniform in its microrelief, soil density and other physical and mechanical parameters. Therefore, most of these forces change in magnitude and direction during the operation of the sowing section. As a result, the equilibrium of the acting forces on the packing wheel may be disrupted. Obviously, the operation quality of the seeding section having an individual packing wheel may only be achieved with steady movement.