Abstract
This paper investigates resonance frequency behavior of three-dimensional, thin-rimmed spur gears (3DTRG) by experimental and theoretical methods. Resonance frequencies of the 3DTRG are measured by using "Power-circulating Form" gear test rig at the speed range from 500rpm to 3000rpm. "Strain Phrase Method" is presented to measure mode shapes of the 3DTRG. Effect of tooth rigidity of the mating gears on resonance frequency behavior of the 3DTRG is also investigated experimentally. Experimental results show that vibration of the 3DTRG is structural vibration of the thin rim and web structures rather than tooth bending vibration like the solid gears. There are many resonance frequencies existing at the same time when the 3DTRG vibrates. Natural frequency and mode shapes of the 3DTRG are also analyzed by 3D-finite element method (FEM). Calculated natural frequencies and mode shapes are agreement with the measured ones very well. Effect of module on the natural frequencies of the 3DTRG is investigated by the FEM analysis. Finally, close and duplicated frequency phenomena of the 3DTRG structural vibration that have never occurred in the case of solid gear vibration are discussed.
