2nd ICAI 2022

International Conference on Automotive Industry 2022

Mladá Boleslav, Czech Republic

Figure 6: Contact pattern in each phase of the experiment

Source: Škoda Auto, a.s., internal materials From this can be concluded that a radial clearance of 0.036mm and an axial clearance of 0.28 mm in this gearing will reduce the contact pattern approximately by 10%. This can cause a reduction in gear life in real operation. MBS simulation calculations were also performed, where the influence of the radial clearance of the needle bearing on the contact pattern was monitored, while maintaining all other boundary conditions of the calculation. The simulation result for three choices of radial clearances of size (0mm, 0.02mm, and 0.05mm) confirms the conclusions obtained from the experiment. The contact pattern tends to decrease with increasing radial clearance (Figure 7).

Figure 7: Effect of radial clearance of the needle roller bearing on the contact pattern

Source: Škoda Auto, a.s., internal materials 3.2 Effect of radial clearance of the shaft bearing (radial clearance of the shaft bearings in the cover) This factor was again investigated on the MQ200 gearbox, this time on the fit of the shafts in the roller bearings in the gearbox cover (Figure 8). A model was developed to determine the contact pattern, which was verified by a real experiment. The input conditions for validation were identical clearances of the individual parts of the system (change gear and shaft fit clearances), identical load torque level and speed.

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