A Note on Tip Relief and Backlash Allowances in Non-Metallic Gears

Previous work on load sharing in non-metallic gears indicated that the change in operating contact ratio is large enough to cause concern. Tests also show that premature contact between the gear teeth can lead to severe flank wear. This paper shows that predetermined amounts of tip relief are needed to minimize this form of wear from occurring. The tip relief suggested in this paper is compared to recommendations given in the British Standard. Finally, for non-metallic gears, allowances for backlash due to elastic deformation of the teeth are suggested.