Computing the planetary pinion gear satellite teeth in accordance with the contact fatigue criterion

The planetary pinion gears are used in the gearboxes, and are designed to convert and transmit torque from an engine to the actuator. As of today, any standard computation methods for this type of a gear are missing. Many works are devoted to determine wear resistance of the friction pairs and the service life of the planetary pinion gear based on the wear limit. The operating experience shows that in certain cases the gear fails due to chipping the surfaces operating under the force contact interaction. The paper considers an approach to determining distribution of forces in the engagement, which makes a significant contribution in finding the contact stresses. Contact stresses are identified using the well-known Hertz formula for a contact of the two parallel cylinders. Contact fatigue of the surface of the planetary pinion gear satellite teeth is computed using various methods. The expected operating time before the fatigue contact failure onset is determined. The paper provides a comparison of the obtained results, and demonstrates a possibility in using the well-known method in computing contact fatigue of the involute gears for the cycloidal engagement.
EDN: MGCDNQ, https://elibrary/mgcdnq

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