Compared with ordinary cylindrical gear reducer and worm gear reducer, the involute servo reducer with small tooth difference has the advantages of small size, light weight, large transmission ratio, high efficiency, large carrying capacity, reliable operation and long life; Compared with the linear pin wheel planetary reducer, in addition to the above advantages, in terms of processing, it can be processed on a general gear processing machine tool with a general tool.Therefore, it has the advantages of lower cost.And what about the carrying capacity? This paper analyzes and discusses the carrying capacity of the gear of the two-tooth difference servo reducer by using the finite element method.
The planetary reducer with small tooth difference is an internal meshing transmission.It is generally believed that its pair of meshing tooth surfaces are convex tooth surface and concave tooth surface respectively, the curvature center of the two is on the same side of the tooth surface, the concave direction of the tooth surface is the same, the curvature radius difference is small, and the contact deformation results in a large contact area. .Therefore, the contact stress of the gear teeth is greatly reduced, and the contact strength is correspondingly improved.At the same time, the bending stress can also be reduced by reducing the height of the addendum, thereby improving the bending strength.In addition, due to the small number of tooth differences, around the theoretical meshing point, there are many pairs of small gap tooth surfaces that are close to meshing. The small deformation caused by the force of the gear teeth makes these small gaps disappear, causing these pairs of tooth surfaces to contact each other, and thus enter Meshing state: If this judgment is in line with the actual situation, then there will be multiple pairs of gear teeth meshing at the same time, which can obviously greatly reduce the transmission impact, making the operation more stable and less noisy.In addition, when the modulus is the same, the transmission capacity should be significantly improved compared with the ordinary external meshing cylindrical gear reducer: this judgment has been confirmed by the application examples in engineering practice.
Smaller modulus transmits larger power, which is the value of involute planetary reducer with small tooth difference.However, it is critical to determine how much the load capacity can be increased by multiple tooth meshing compared to single tooth meshing.As mentioned above, the increase in load carrying capacity is mainly due to the engagement of multiple pairs of gear teeth.How to distribute the force of each pair of teeth is a statically indeterminate problem, and it is impossible to find an analytical solution.Therefore, the traditional algorithm has to be calculated according to a pair of teeth meshing.Although many factors such as the tooth shape are fully considered, the changes brought about by the meshing of multiple pairs of teeth cannot be considered. Therefore, such calculation results are largely conservative, and the load-carrying potential of the meshing of multiple teeth cannot be exploited.Using the finite element analysis software COSMOSDesign-STAR for calculation can solve this problem well: This paper introduces the use of finite element method to illustrate the load-carrying capacity of a pair of meshing teeth and multiple pairs of teeth meshing when the maximum stress is equal. The difference in the carrying capacity of the two-tooth difference planetary reducer is calculated according to the meshing of a pair of teeth and the meshing of multiple pairs of teeth.
