ANALYTICAL DETERMINATION OF ASYMMETRIC PARAMETERS DISK HARROW

Abstract

Having analyzed the technologies of pre-sowing field preparation, it should be concluded that the soil is processed before sowing with cultivators, disk, tooth and needle harrows, as well as soil tillers. Rolling before sowing ensures the destruction of soil lumps, as well as partial leveling of the field surface. However, the task of qualitative preparation of the field for sowing with the use of disk harrows is currently insufficiently solved, therefore it is necessary to substantiate the rational design parameters of an asymmetric disk harrow containing working bodies, which include, in particular, spherical disks. The following should also be noted, if the harrow is intended for use on harder, for example, chernozem soil, then the rod is attached to the hole further from the axis of rotation of the two-armed lever, which ensures the distance of the attachment device from the middle line of the harrow, which conditions the preservation of its balance when working on such soil. The process of rectilinear movement and rotation of spherical disks with a certain radius R in the soil at a depth h, which are installed at different angles to the direction of harrow movement, is considered. In the work, the impact of spherical disks with the remains of stubble, chopped straw was considered, it was established that spherical disks should be clamped between the sharpened cutting edge and the soil and cut them. It has been established that for guaranteed rotation of a spherical disk in the soil with minimal slippage and rolling resistance, its diameter must be substantiated. Since the spherical disk for soil cultivation is installed at an angle of attack α, to the direction of harrow movement, the projection of the spherical disk in the longitudinal-vertical plane is an ellipse with semi-axes. The rational diameter of the spherical disc of the asymmetric disc harrow under the conditions of its rotation in the soil with minimal values of sliding and rolling resistance, as well as a high-quality process of cutting the soil, stubble and soil displacement, is theoretically substantiated. It was established that the rational values of the diameter of the spherical disc of the asymmetric disc harrow depends on the depth h of soil treatment, the angle of attack α and the physical and mechanical properties of the soil.