Identification of parameters of pneumatic and mechanical seeding device under the influence of vacuum

Kateryna Vasylkovska, Oleksii Vasylkovskyi, Serhii Leshchenko, Mykola Sviren and Mykola Moroz

Abstract: Modern pneumatic and mechanical seeding devices of tilled seed drills provide effective one-seed dosing, but due to a significant difference between the fly- out velocity from the disk (up to 0.5 m/s) and the seed drill velocity (up to 2.5 m/s), there is a redistribution of the calculable intervals between seeds in the furrow. The solution of this task is to create the appropriate conditions for ensuring high velocity of the seed disk rotation. The construction of a new pneumatic and mechanical seeding device for precision seeding of tilled crops with peripheral location of cells on a seed disk and a passive device for removing unnecessary seeds in a centrifugal method is suggested.
The analysis of the design of the seeding device allows asserting that it is possible to catch, remove and drop the seeds even without the formation of rarefication in the vacuum chamber. Removal of unnecessary seeds is carried out by means of manufacturing in the body of the device a passive device with a cavity, to which, under the action of centrifugal forces, unnecessary seeds fall and go back to the filling zone. In order not to remove the main seed along with the unnecessary seeds when the rotation velocity of the seed disc approaches the velocity of the seeding device, additional force should be applied that would keep the main seed in the cell, that is, the force of suction.
Thus, the presence of suction force will increase the size of the cavity (the angle which determines its size) to 0.26...0.32 rad at the angular velocities of the disk, respectively, 25...30 rad/s. That will guarantee the removal of unnecessary seeds, because their movement along the blade in this case, exceeds half its diameter.

Keywords: blade; cavity position angle; removal of unnecessary seeds; seed; seeding disk

Date published: 2020-10-20