Evaluation of Runout Deviation at Bevel Gears based on Pitch Measurements

The ever-increasing number of manufactured gears requires, among other things, shorter quality inspection times. With the introduction of coordinate measuring machines (CMM), the importance of classic measuring methods for bevel gears decreased more and more [1]. The classic direct runout measurement is a function oriented, over-all inspection of a bevel gear. Its result is one of the criteria to classify gears in standardised accuracy grades (former quality groups). Instead, modern bevel gear inspections with CMMs only measure the pitch deviations on both flanks and subsequently estimate runout deviation based on explicitly less information than the classical (direct) runout measurement. This paper presents a new approach for this evaluation problem and compares theoretical and experimental runout results carried out with several CMMs.