Increasing the smoothness of the course of the forage harvester by optimizing the mass-dimensional and inertial parameters of its body

Abstract

The scientific-methodical substantiation and practical recommendations on stabilizing the movement of forage harvesters are proposed. Calculation of optimal mass and inertial parameters of the hull, as well as elastic properties of tires as the main element of the combine suspension system is theoretically grounded. The developed technique on the example of the combine prototype shows the possibility of calculating the optimal stiffness of tyres and weight of additional counterweights installed in the base of the machine to ensure the equality of natural frequencies of front and rear axle oscillations on elastic tyres. The modeling of the combine’s movement on the subsoil road and asphalt concrete highway with different speeds has been carried out on the basis of mathematical and imitation model of the combine developed by the authors earlier. In the order to evaluate the efficiency of the proposed method of improving the smoothness of running the comparison of peak and mean square values of the pitch angle of the hull, as well as the levels of vertical vibroaccelerations in the cabin on the floor under the seat of the operator of the combine in its basic design and improved version due to the use of counterweights of a given mass and optimized stiffness of tires. A simulation was used to perform an octave analysis of the workplace vibration load. It is shown that optimization of mass and inertial parameters of the body, as well as elastic properties of the combine harvester tires on the main driving modes provides improvement of comfort of the operator’s working place, especially in the most dangerous for human frequency range. The driving modes are defined, on which the best effect of rework is achieved. The stabilization process is described. The conclusions on the direction of further research are presented.