Double arc tooth is a kind of original tooth mechanism to meet the requirements of KMI drive. The tooth profile has a special curve unique to the double arc tooth profile, which can be in continuous contact with the same tooth profile. In addition, the stress concentration is relieved by enlarging the width of the groove relative to the tooth thickness and the R of the tooth bottom.

Gear contact will continue from the beginning of engagement. Through the continuous contact of gears, the number of teeth engaged at the same time will reach about 30% of the total number of teeth. The KMI drive with double circular arc tooth profile is a kind of technical innovation that can keep the smoothness of the application of traditional models, and realize a comprehensive leap in accuracy, strength, rigidity and service life.