2nd ICAI 2022

International Conference on Automotive Industry 2022

Mladá Boleslav, Czech Republic

In the experiment, a gearbox with a radial clearance of 0.036mm and axial clearance of 0.28 mm was used, which correspond to the above ranges. A progression was made from the serial produced gearbox with a change gear mounted on needle bearing (Figure 5a), to only the radial clearance adjustment by replacing the needle bearing with a sleeve without radial clearance (Figure 5b). Next, only the axial clearance adjustment using thrust washers (Figure 5c), to finally both clearances adjustment on the gear (Figure 5d). Figure 5: a) Serial produced gearbox, change gear mounted with radial and axial clearance on needle bearing b) Gear radial clearance adjusted, needle bearing replaced by precise sleeve c) Gear axial clearance adjusted with a precision thrust ring/washer d) Gear radial and axial clearance adjusted – combination of both adjustments

Source: Škoda Auto, a.s., internal materials From the experiment performed at a load of 30 Nm, when comparing the contact pattern (Figure 6), it was found that the radial clearance adjustment affected (shifted and, due to microgeometry, increased) the contact pattern in the magnitude of 10% of the tooth width. The same effect was also produced by the axial clearance adjustment. Adjustment of both clearances simultaneously did not cause any further significant change in the contact pattern. Assessment of the change in the size of the contact pattern was made by dividing the tooth width into ten bands, as shown in Figure 6.

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