How to calculate the bearing capacity of planetary reducer

How to calculate the bearing capacity of planetary gear reducer, involute small tooth difference planetary reducer has the advantages of small volume, light weight, large transmission ratio, high efficiency, large bearing capacity, reliable operation and long life compared with ordinary cylindrical gear speed reducer and worm gear reducer; compared with cycloid pinwheel planetary reducer, in addition to the above advantages, in the processing aspect, general tools can be used for processing on general gear processing machine tools.

Therefore, it has the advantages of low cost. What about the bearing capacity? In this paper, the finite element method is used to analyze and discuss the gear bearing capacity of the two-tooth difference planetary reducer.

The small tooth difference planetary reducer is an internal meshing transmission. Generally, it is considered that a pair of meshing tooth surfaces are convex tooth surface and concave tooth surface, the curvature centers of the two are on the same side of the tooth surface, the tooth surface is concave in the same direction, and the difference in curvature radius is very small, resulting in a large contact area due to contact deformation.

Therefore, the contact tooth surface stress is greatly reduced, and the contact strength is correspondingly improved.

At the same time, the bending stress can be reduced by reducing the tooth tip height, thereby improving the bending strength. In addition, due to the small number of tooth differences, there are multiple pairs of close-meshing small clearance tooth surfaces on the left and right of the theoretical meshing point, and the slight deformation of the wheel teeth under load makes these small clearances disappear, causing these pairs of tooth surfaces to contact each other, thus entering the meshing state: If this judgment is in line with the actual situation, multiple pairs of wheel teeth can mesh at the same time, which can greatly reduce the transmission impact, making the operation more stable and the noise smaller.

In addition, when the module is the same, the transmission capacity should be significantly improved compared with the ordinary external meshing cylindrical gear reducer: there are application examples in engineering practice to confirm this judgment.

The value of the involute small tooth difference planetary reducer lies in transmitting a large power with a small module. However, the key is how to determine how much the bearing capacity can be increased by comparing multi-tooth meshing with single-tooth meshing. In summary, the purpose of increasing the bearing capacity is because multiple pairs of wheel teeth are involved in meshing.

However, how to distribute the force on each pair of teeth is a hyperstatic problem, and it is impossible to find an analytical solution. Therefore, the traditional algorithm still calculates according to a pair of teeth meshing. Although many factors such as tooth shape are fully considered, the changes brought about by multiple pairs of teeth meshing cannot be considered, so the calculation results are greatly biased towards conservatism, and the bearing potential of multi-tooth meshing cannot be developed.