Effect of Contact Ratio on Friction Loss of Internal Gear Drives.

Abstract

This paper describes the relationship between the friction loss and contact ratio of internal gear drives. Friction loss of internal gear drives with various contact ratios was measured using a power circulating-type internal gear testing machine, by the oil immersion formula, whose method is based on the oil temperature rise due to the power loss in the gear drives. From statistical analysis results for the experimental data, it was found that the friction loss ratio of the internal gear is influenced most by gear speed, and next by contact ratio and that applied torque has no significant effect on the gear friction loss ratio. The gear friction loss ratio has a minimum value at the contact ratio between 1.3 and 1.5. Furthermore, the contact ratio and the friction loss of internal gear drives were calculated, and the effect of the contact ratio on the gear friction loss was discussed.