Abstract
The conical involute gears have been applied to automotive parts such as 4WD transfer. To apply for automobile, high capacity and higher quietness are required. In general, the tooth contact of conical gear pair is point contact, hence the large ease off happens even though each tooth surface has no manufacture error. From this characteristic, the tooth surface durability of conical gear pair is thought to be generally small. To clarify the tooth surface durability of conical gears we developed the evaluation method of tooth contact stress distribution on conical gear surface taking an ease off shape and a tooth surface modification into consideration and evaluated a pitting test result by this method. The relationship between the maximum contact stress and pitting life can be put on the pitting S-N curve of cylindrical gears. The edge contact found often cylindrical gear surface at heavy load isn't found on conical gear surface because of large ease off shape.
