Determination of the Strength Characteristics of Traction Gears Under Shock Loads

The goal is a model-experimental study of the vibration that occurs in the nodes of the motor-gear unit (hereinafter referred to as MGU) installed on the motor bogie of an electric train under operating conditions. Vibration measurement was carried out experimentally on a motor stand using vibration sensors of the SKF CMXA 80 type, installed on the casing of the traction gearbox and the frame of the traction motor. For measurements, a system was used that allows continuous recording of the vibration transducer signal over eight channels. Experimental data on the parameters of vibrations that occur on the bearing shield of the output shaft of the MGU were obtained by simulating the departure of a motor bogie by instantaneous load shedding. A pattern has been established that the vibration level under skid conditions in three coordinates X, Y, Z has sharp bursts of activity. During the MGU operation in the traction mode, it was found that a sharp increase in the amplitude of harmonics with frequencies that are multiples of the gear frequency is associated with the coincidence with the natural frequency of the MGU case. When switching to the coast down mode in the frequency range of about 1.5 kHz, a random vibration is recorded on the MGU body, the RMS acceleration value of which exceeds 50 $\boldsymbol{\mathrm{m}/\mathrm{s}^{2}}$, which is comparable to the acceleration value when passing the skid.