Development of a Force Element for the Emulation of the Dynamic Behaviour of Bevel Gears: Simulation of Excitation Mechanisms in Tooth Mesh for Detailed Analysis of Noise and Vibration Behaviour

摘要

Like other machine elements, gear transmissions have to face higher requirements concerning load carrying capacity and noise behaviour continuously. Regarding growing customer's demands on comfort and the development of more restrictive legal requirements for acoustic emission the running and noise performance is focussed more intensely in gear research. This means that the dimensioning of gears for certain operating ranges has to consider dynamic additional loads besides static strains as well. The dynamic additional loads originate from vibration mechanisms in the tooth contact. Close to critical rotational-speed ranges in terms of vibrancy response they can rise heavily and exceed static nominal loads. The load peaks with their resulting vibration oscillations lead to an intensified noise emission of the transmission. A possibility to reduce the acoustic emission is the downsizing of existing force amplitudes. The utilisation of calculative vibration analysis tools establishes the opportunity to deconstruct the force spectrum and to evaluate the appearing force amplitudes. This cognition results in a movement of the acoustic research from subjectively influenced noise test objectively and automatically executed simulation methods. They enable the user to minimize error rates. Thus damages to the company's image can be decreased as well as follow-up costs, both in a competitive and transparent manner. Referring to these reasons a research project was realised to develop a force element which gives the opportunity to display the circumstances during the tooth contact of bevel gears [1], [2], [3]. The force element allows determining the dynamic additional loads during the tooth contact. Therefore the loadfree and the loaded transmission error are analysed. The identification of the courses of the mentioned factors has required a quasi-static analysis varying a series of load states, in this report the functionality of the force element is presented. Furthermore a multi body simulation of a test rig with a bevel gear set based on the MSC.ADAMS software [4] was developed. The multi body simulation uses the developed force element of the tooth mesh. The behaviour of the force element and the multi body model was compared with real test rig results.