The research on the dynamic characteristics of three ring reducer starts from the experiment. These experimental studies are mainly to apply excitation force to the three ring reducer to obtain its natural frequency, or to test the acceleration of the internal gear plate and the box and other relevant parts. However, there is no systematic study on the vibration of the three ring reducer, nor the establishment of the dynamic equation of the system, so there is a lack of understanding of the dynamic nature of this transmission.
The inherent modal parameters of the system are obtained by impulse excitation test of the three ring reducer. By studying the swinging force and moment of the inner gear plate of the three ring reducer, a method of eliminating the swinging moment by counterweight balance is put forward. It is considered that the meshing angle and bearing stiffness of the gear pair have a great influence on the vibration of the three ring reducer. Properly increasing the meshing angle of the internal meshing gear pair and the shaft stiffness of the transmission system can effectively reduce the vibration, while the modification of the tooth profile of the internal gear plate has no obvious effect on the vibration reduction. ]It is proposed that the first stage synchronous belt reducer should be added, and the thickness of the middle inner gear plate should be set to twice the thickness of the inner gear plate on both sides, and placed 180 ° with the inner gear plate on both sides, so as to realize the balance of swing force and swing moment. The method of adding load balancing ring is put forward to improve the vibration performance of three ring reducer. For example, a polytetrafluoroethylene bushing is added between the output shaft and its bearing, and a load balancing ring is added between the outer ring of the output shaft bearing and the bearing seat. Literature [32] thinks that there is a gap between the flat key and the high-speed shaft, and between the flat key and the eccentric sleeve, which will cause fretting wear. The solution is to increase the interference between the eccentric sleeve and the shaft diameter or to make the shaft and the eccentric sleeve into a whole. Later, for the vibration problem of the three ring reducer,] the effect of oil film force on the vibration of the three ring reducer was specially studied. Its principle is to insert a floating sleeve which can move freely between the eccentric sleeve of the input shaft of the three ring reducer and the inner ring of the inner toothed plate bearing.
When the eccentric shaft rotates, the floating ring rotates at an angular speed lower than the shaft speed under the action of oil film force. This structure reduces the rigid contact between the eccentric sleeve and the bearing inner ring, the eccentric sleeve and the input shaft, and improves the service life of the eccentric sleeve and the planetary bearing. The test results show that the oil film formed inside and outside the floating ring has good load balancing effect and damping effect on the three ring reducer.