The reduction of component size and oil volume of current automotive and aeronautical transmissions, along with the increasing input speeds, are pushing gear teeth bulk temperatures to their scuffing limit. Even with development of new lubricant additives and coatings, high temperatures may produce other issues. This paper analyzes the effects of thermal distortion on the profile geometry and tooth contact parameters in the transverse plane of a spur gear by calculating the steady-state temperature distribution relevant to immersion depth, sump temperature, and lubrication regime in the contact area. Then, thermally distorted geometry and tooth contact analysis is computed by means of a 2D finite element model where load distribution, transmission error, backlash, and other parameters will be analyzed. The results of the study will allow one to set the limits of design backlash to avoid gear jamming and to size the initial profile shift or tooth modifications to reach the desired contact behavior.

ISBN: 978-1-64353-010-9
Pages: 13
Authors: Jon Larrañaga, Ibai Ulacia, Aurea Iñurritegi, Aitor Arana, Jon German, and Julen Elizegi