Investigation of the operation of a needle harrow when driving on soil

The state of the problem of surface pre-sowing tillage for sowing of small-seeded crops is described, the solving of which will improve the efficiency of their cultivation. The expediency of using needle harrows with a passive drive and straight-line needles radially mounted on disks is shown. An analysis of their work revealed a number of unexplored issues that need to be resolved for the further improvement of these working bodies in order to increase productivity, and a higher quality process performance. The differential equations of the movement of the harrow disk, taking into account the moment of the friction force acting from the soil on the needle during the rotation of the disk, and the resistance force overcome by the needle when leaving the soil, are compiled. The analysis of soil piercing with needles of a needle harrow; the forces acting on the needles when interacting with the soil were specified, taking into account the experimental coefficients, the characteristics of the movement of needles were considered; the results of the refined analysis of the forces acting on the needles of the harrow during tillage and other factors; a refined relationship was obtained to determine the driving force of the needle harrow, taking into account the resistance force overcome by the needle when leaving the soil, which will improve the accuracy of calculations.