Theoretical research of needle-shaped harrow operation expended on soil pinching by needles

Abstract

Needle–shaped harrows developed by us belong to harrows which represent known designs which are carrying out rolling in longitudinal–vertical plane. According to number of disks with needles, we have developed single- and double- disk harrows, under connection of which there can be formed a multi–disk harrow. Analysis shows that in order to improve impact of needles on soil in places of its pinching, it is necessary that in first disk with needles, the angle between which is equal to α, and in other disk, which is located next to the first disk (i.e. parallel to first disk), needles are also at angle α, however, these needles together with disk should be rotated in direction of movement of disks (or against direction of movement of these disks) at angle α/2. During the design of double-disk harrow, there was set the task of changing the design of needle harrow to ensure increase in uniformity of impact of needles on soil surface.