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The article discusses the features of performing a kinematic analysis of a controlled power mechanism, which additionally implements a force turn mode with a zero radius. The mechanism can be used for transmission of wheeled and caterpillar transport and technological machines. Related mechanisms are mainly used on cars to improve handling, stability, traction and dynamic properties in difficult road conditions, but do not provide a turn with a zero radius. In Russia, such mechanisms are not produced, although theoretical studies are underway, the results of which will make it possible to determine the main parameters of the mechanism and to synthesize its kinematic scheme. The approaches proposed in the article are based on the methods used in the kinematic analysis of planetary gears, however, it is taken into account that the power distribution mechanism during operation has two degrees of freedom. The presence of structural and functional similarity between the vehicle power distribution mechanism and the tracked vehicle turning mechanism is indicated. In one of the modes of operation, the mechanism under consideration functions similarly to the existing ones: due to the controlled sliding in the disk controls, the turning radii pass from infinite (rectilinear) to minimum (calculated). The calculated turning radius is the radius obtained in the absence of slippage in the friction controls of the power distribution mechanism. In the other, a turn is performed in place with a zero radius. When the vehicle is in a straight line, the controls are disabled, the absence of power circulation in the drive axle is ensured, as in traditional transmissions, by the differential, which is part of the mechanism. [ABSTRACT FROM AUTHOR]

A progressive direction in the development of mechanization for pre-sowing tillage is the use of tillage machines or aggregates with combined working bodies, which make it possible to combine several operations in one technological process. The subject of the study is the energy performance of the unit with combined working bodies. The object of the study is the OKP-7N cultivator intended for pre-sowing and other types of cultivation to a depth of 3 to 15 cm. When performing the work, experimental studies were used using the interaction of working bodies with the soil. The processing of the field section was carried out in the II, III and IV gears of the tractor with the maximum fuel supply. The speed of movement of the unit on the indicated gears was determined in triplicate, the depth of tillage was kept constant at the level of 0.15 m. cultivator. When the unit was operating in the fourth gear of the tractor, the engine overload mode was observed, so the speed of the unit decreased even compared to the speed in the third gear, and the traction resistance of the cultivator was at the same level. The hinged connection of the cultivator without a blocker provides longitudinal copying of the field surface of the tractor separately, and separately of the cultivator, as a result, the traction resistance of the cultivator decreases by 8 ... 10%, the speed of the unit increases by 31%, when the tractor is operating in the rated load mode. [ABSTRACT FROM AUTHOR]

The use of direct sowing seeders, the sections of which consist of modules for local loosening of the soil and sowing, is most appropriate when growing grain crops. During the operation of the seeder, the wavy disk provides a strip grinding of the soil, in which the coulter system lays seeds. When preparing the soil for sowing, the degree of use of the total specific energy costs is about 16%. Therefore, significant savings in energy costs to produce crop production can be achieved by reducing the specific traction resistance of the working bodies of agricultural machines. When cultivating the soil, its individual particles or layers under the influence of a wavy tillage disk move in space, change their mutual location and the soil passes into another physical state. Its geometric shape has a very significant influence on the magnitude and direction of the forces of interaction between the soil and the tillage disk. The form of the tillage wavy disk is justified, the influence of the parameters of the experimental tillage disk on the energy indicators of its operation is determined. [ABSTRACT FROM AUTHOR]

The article discusses the issues of reducing the productivity of grain cleaning machines as a result of clogging holes with seeds of the culture being cleaned and impurities. The analysis of indicators reflecting the clogging of sieves and their throughput is given. It is noted that the reduction of the clogging of the sieves is provided by the use of additional devices, the work of which is aimed at removing stuck seeds from the sieve cells. In order to determine the relationship between the physical and mechanical properties of seeds and the modes of operation of the sieve that affect the clogging of the sieves, an analysis of the forces holding stuck seeds in the cells of the sieve is given. Which showed that the main force holding the stuck seeds in the cells is the friction force. Gravity and elasticity have a significant influence on the amount of friction force of the seed against the cell walls. Graphs of the dependence of the change in the force pushing the grain through the hole on the angular frequency of the sieve oscillations are obtained. In addition, graphs of the dependence of the change in the force to be applied to the grain wedged in the sieve on the relative deformation of the grain are constructed. The obtained research results allow us to substantiate the parameters of devices for cleaning sieves, which will increase the productivity and quality of the products obtained. [ABSTRACT FROM AUTHOR]