One of the significant directions of scientific research in terms of improving the design of sowing machines and increasing their adaptability to modern requirements of automation is the creation of dispensers that provide adjustment of the seeding rate during the operation of the sowing machine. Specialists of the Siberian Research Institute of Mechanization and Electrification of Agriculture have developed a sample of a pneumatic sowing machine dispenser, which was used as a prototype in the study. The dispenser used allows for a smooth adjustment of the seed rate in accordance with the map task, as well as automatic shut-off of the seed supply to the seed line when the machine turns at the headland to prevent overconsumption of seeds and reseeding. The purpose of the research is to determine the design and technological parameters of the experimental dispenser of the pneumatic sowing machine. To achieve the set goal the following tasks were formulated: 1) to conduct a laboratory study of the process of seed metering in the experimental dispenser of the pneumatic seeding machine; 2) to determine the regularities of mutual influence of significant factors on the throughput capacity of the dispenser and describe them by regression equations. In accordance with the listed tasks the process of seed dosing on the laboratory unit was studied. In the course of experimental data processing, regression dependencies were obtained. According to the characteristics of the obtained equations, it is found that the most significant influence on the throughput capacity of the dispenser is the volume of the dispenser coil. Maximum performance of the dispenser is noted at rotor speeds in the range of 80–100 rpm. The highest feed rate and avoidance of spontaneous seed leakage from the dispenser into the seed pipe are achieved at a gate height of the dispenser discharge window within 2 cm. The results of the research can be used to finalize the design of the dispenser in order to use it as an actuator of the system of complex automation of the sowing unit.
