Authors: A. Johnney Mertens; S. Senthilvelan
Addresses: Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati-781039, India ' Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati-781039, India
Abstract: Asymmetric tooth profiles with different pressure angle at drive and coast sides are being considered to enhance the gear performance. In this work, experimental investigations were carried out to evaluate the fatigue and wear performance of injection moulded asymmetric polypropylene spur gears using the power absorption gear test rig. Test gears exhibited wear failure at lower loads and tooth bending failure at higher loads. Periodic measurement of gear tooth thickness and weight loss was carried out to quantify gear tooth wear. Sudden rise in measured gear temperature and failure morphology confirmed bending failure at higher loads. The results revealed that asymmetric gears exhibited inferior performance than that of symmetric gears. This behaviour is due to the reduced contact ratio, increased normal load and increased height at which worst load act on the gear tooth profile for the considered test conditions.
Keywords: asymmetric tooth profiles; fatigue; wear; injection moulding; polymer gears; gear durability; involute gears; spur gears; polypropylene; gear teeth; gear tooth bending; gear tooth thickness; weight loss; gear temperature; asymmetric gears; gear tooth profiles.
International Journal of Powertrains, 2016 Vol.5 No.3, pp.264 - 280
Received: 04 Feb 2015
Accepted: 16 May 2015
Published online: 12 Sep 2016 *