Reducing dynamic loading of mobile power equipment from external impacts and increase of their traction and dynamic parameters
Increasing energy saturation of modern mobile power equipment (MPE) is accom-panied by an increase in their dynamic loading of the external influences that have an oscillatory character with variable frequency and amplitude, it causes higher vibration processes in the system soil – propelling device – engine and transmission installation, which leads to lower traction qualities, and hence performance deterioration of technological parameters of tillage and destruction of its structure. To eliminate the dynamic loading of external influences different elastic-damping device are installed in the clutch, transmission, drive of the drive wheels, on the shafts of PTO, trailer and hitch MEAs. The most effective way to reduce the non-uniformity of the draft resistance of mounted agricultural machinery, surface irregularities of the field and the physical and mechanical properties of the soil is installation of elastic-damping drives (EDD) closer to the drive wheels of MEA. As the object of the investigation universal – cultivating tractor ЛТЗ–155 was used with a variety of agricultural machinery and transport unit, equipped with rigid axle shafts with a diameter of 50 mm and with EDD. Tractor ЛТЗ–155 was equipped with sensors and strain-measuring units and devices: inductive sensors on the drive wheels and track-measuring device, straingauge couplings for measuring the torque on the semiaxes; acceleration indicator installed on the driving axles, as well as a flow meter to determine the fuel consumption, time was determined on marks of oscilloscope. The results showed that the spectral density of distribution of the torque on leading semiaxes with hard drive has a maximum speed of 1.6...2.8 Hz, which are in the field of natural vibration frequencies of skeleton of the tractor. Introduction of EDD in all semiaxes of ЛТЗ–155 tractor with a plow ПЛН–4–35 reduces the maximum spectral density of the torque on given semiaxes in 2.1 times and in 2.6 times on the front ones and their shift to lower frequencies 1.3…1.6 H. The amplitudes of the oscillations of the tractor skeleton through EDD decrease in 1.15...1.3 times. When operating a tractor with cultivator КРШ –8,1 behind the maximum spectral density of torque with a frequency of 0.8...2.0 Hz is eliminated almost entirely by the EDD. Installation of EDD on all tractor semiaxes with a transport unit reduces the maximum spectral density of torque to the rear spindles till 1.6 times, and on the front ones up to 3 times and their shift to lower frequencies of 0.1...0.8 Hz. Traction tests with EDD on all tractor semiaxes showed that when EDD is got tractive power increases by 6...11 %, and slipping of propelling unit decreases for 1...5 % (absolute value with Pkr = 10...35 kN).