The time-varying meshing stiffness excitation and the transmission error excitation are two very important excitations in the actual operation of gears, which will directly affect the vibration response of the gear pair. The existence of tooth thickness deviation will directly affect the meshing stiffness and transmission error of the gear pair. This is because the tooth thickness deviation changes the working tooth profile of the gear, which makes the number of teeth participating in the meshing change at some time in the meshing process. Therefore, this paper first analyzes the influence of tooth thickness deviation on the meshing stiffness and transmission error of gear pair. Based on the meshing stiffness and transmission error excitation calculation model, the tooth thickness deviation without tooth thickness deviation and tooth thickness deviation without tooth thickness deviation are calculated Δ The meshing stiffness and transmission error of the gear pair at ES2.
The single tooth meshing stiffness curve of gear pair under two kinds of deviation is shown in Figure 1.
It can be seen that the meshing stiffness curve of a single tooth in a meshing cycle roughly presents two parabola, which is due to the fact that the meshing line is located on the upper part of the tooth surface at the instantaneous position of the helical gear entering and exiting the meshing, which is farther from the constraint position, and the relative deformation of the gear pair is larger and the meshing stiffness is smaller. When the length of the meshing line is the same, the meshing stiffness is greater when the meshing line is far away from the position of entering meshing and exiting meshing. Therefore, the meshing stiffness curve in a meshing cycle roughly presents two parabola, which is consistent with the conclusion given. At the same time, the existence of tooth thickness deviation makes the single tooth meshing stiffness of the gear pair reduce, which is due to the existence of tooth thickness deviation resulting in the reduction of gear tooth thickness.
The transmission error of gear pair under two kinds of deviation is shown in Figure 2.
It can be seen that in a meshing cycle, the transmission error of the gear pair changes with the gear angle, and the transmission error of the gear pair increases obviously due to the tooth thickness deviation. As one of the most important internal excitation of gear transmission system, the increase of transmission error excitation will directly affect the vibration characteristics of gear pair.