Circular arcis a point engagement gear, which has the advantages of high bearing capacity, long service life and good running-in performance. It is widely used in metallurgy, mechanical mining, petroleum machinery and other industries.
On the basis of single circular arc helical gear, double circular arc helical gear and four circular arc helical gear are developed. The single tooth of single circular arc helical gear has only one engagement point within one axial pitch px, so the stress is concentrated on this point. According to its engagement characteristics, double circular arc helical gear has two engagement points in one axial pitch PX of a single tooth.Then the stress will be distributed at these two points of engagement, thus improving the meshing strength of the gear; similarly, the stress of the four-arc helical gear will be distributed at the four points of engagement, theoretically carrying capacity is four times that of the single-arc gear.
It is proved by finite element method that the bearing capacity of four-circular arcis more than 60% higher than that of double-circular arc gears.Literature  By calculating the engagement characteristics of four-circle-arc helical gears, it is proved that four-circle-arc helical gears have higher overlap degree, more engagement points and smoother transmission than double-circle-arc gears.In this way, a new type of gear – hexagon-arc helical gear is put forward, and the meshing characteristics of hexagon-arc helical gear are calculated.
The six-circle arc helical gear theoretically improves the load-bearing capacity and transmission smoothness of the gear. By calculating the engagement characteristics of the six-circle arc helical gear, it can be seen that the engagement points and the engagement teeth of the six-circle arc helical gear are functions of the tooth width B. By reasonably selecting the tooth width of the six-circle arc helical gear, as many engagement points and the logarithm of the engagement teeth can be obtained.To improve the bearing capacity and economic benefits of gears.