A novel calculation method of long period pinion axial displacement and meshing impact force for double helical gear considering asymmetry error

The cumulative pitch errors of the left and right helical gears are the main source of the asymmetry error for the double helical gear. In this paper, a new three-dimensional loaded tooth contact analysis (3-DLTCA) model of double helical gear considering long period asymmetry error is proposed. The desired error (modification), undesired error (cumulative pitch error) and the change of normal clearance increment of left and right helical gear pairs caused by the axial shift of the driving pinion are considered in the model. Based on the new 3-DLTCA model, combined with the equivalent gap of the current meshing tooth pair, the meshing impact force (MIF) of the current meshing tooth pair in each meshing period is calculated. The results show that the proposed model can quickly and accurately calculate the long period end loaded transmission error (ELTE) and pinion axial displacement (PAD) of double helical gear with asymmetry error. Moreover, the long period asymmetry error of double helical gear has great effect on the MIF for left and right helical gears.