A Study of the Stress-Strain State of the Planetary Carrier Cheek

Planetary gears are commonly used in drive technology due to their high load capacity and good weight and size parameters. Among planetary gears, multi-satellite structures with a minimum number of excessive links are most widely used. They have a close to uniform distribution of the load in the engaged gears, which has a positive effect on the strength and bearing capacity of the drive. Such designs include planetary gears, the satellites of which are mounted on spherical bearings, and one of the main links (most often the sun gear) is self-aligning. This provides a theoretically uniform distribution of the load in the engaged gears when the mechanism has three satellites. However, high-loaded drives often use designs with a large number of satellites where the load is distributed unevenly due to gear manufacturing errors. The deformability of individual transmission elements has a significant positive effect on the distribution of the load in the gears, thus compensating for the manufacturing errors. In view of this, the authors propose a multi-satellite planetary gear with a carrier made with grooves in the cheeks, which reduces their rigidity and provides, with a rational choice of the parameters of the mechanism, an increase in the mechanism’s bearing capacity. When determining the carrier cheek’s compliance, two schemes of loading in the coupling zone with the axis of the satellite (uniform and nonuniform) are considered. The solution is obtained using Mohr’s integrals. A numerical analysis of the stressed-strain state of the carrier cheek performed using the finite element method in the SolidWorks environment showed that the results of the analysis were close to the theoretical ones. They corresponded to a uniform load distribution in the coupling zone of the satellite axis and the carrier cheek. The obtained dependences can be used in the design of a mechanical drive to determine the coefficients of the uneven load distribution over the planetary gear satellites and over the individual crowns of the satellite.

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