Abstract: The loaded tooth contact analysis (LTCA) plays an important part in designing the spiral bevel gear drives with high performance. The tooth edge contact of spiral bevel gears in operating is unavoidable， specially under bearing loads. But the tooth edge contact is ignored frequently which makes the analyzed results to deviate from real operating conditions. An accurate and very convenient edge tooth contact analysis technique of spiral bevel gears is developed， by which the contact points on tooth edges could be determined. Further， the main directions between two tooth surfaces on every edge contact point， that is， the possible contact point pairs， are found by a numerical search method. Finally， the tooth edge contact problem is resolved successfully. The compared and analyzed results show that the tooth edge contact has considerable influences on the strength and dynamics behaviors of spiral bevel gears and a complete engagement course under load can be obtained.

Key words: Edge contact, Loaded contact, Spiral bevel gear