Under no-load condition, gear has two-sided impact phenomena and frequently falls out of teeth. Maximum dynamic meshing force and root mean square value are used as evaluation indexes of no-load knocking characteristics.
For two different no-load states, there is a big difference in no-load speed.In the first no-load state, the range of no-load speed varies depending on the speed range of the steady-state engine operation; in the second no-load state, the range of no-load speed varies depending on the speed range of the engine at idle speed.
The steady-state operating speed of the engine ranges from 1000 r/min to 4200 r/min, while the idling speed of the engine is generally between 600r/min and 1000 r/min.Therefore, the range of no-load speed is [600r/min, 4200r/min], and the interval between values is 200r/min.
The trend of maximum and root mean square values of engagement force with no-load speed is shown in the figure.It can be seen from the diagram that with the increase of no-load speed, the maximum dynamic load on tooth surface and back has no obvious change trend, and the mean square root value of dynamic meshing force has an increase trend.
At different speeds, the maximum dynamic loads of tooth surface and back are 56240N and 54830N respectively, which are 0.36 times higher than the minimum dynamic loads of 41450N and 40210N.At different speeds, the maximum and minimum RMS of dynamic load are 7040N and 6600N, respectively, with an increase of 6.7%.