Single circular arc tooth profile arc tooth profile a single tooth is shown in Figure a. its tooth profile curve is an arc, and the tooth line of the gear is an arc, and the section at the center of the tooth width is symmetrical. There are only two meshing points in a single tooth of a single circular arc gear. A single tooth of double circular arc profile gear has at least two meshing points and at most four meshing points. A single tooth of a four arc profile gear has at least two meshing points and at most eight meshing points. When the gear teeth enter the meshing transmission, the two meshing points of a single tooth of a single circular arc profile gear remain unchanged, while the meshing points of a single tooth of a double circular arc profile gear and a four circular arc profile gear change alternately with the rotation of the gear.
The meshing process of single circular arc tooth profile circular arc tooth line gears is shown in Figure b. the axes of a pair of gears meshed in the figure are O1 o’1 and O2 o’ 2 respectively, the meshing points of the teeth are K1 and K2 respectively, and the intersection points of the normal of the meshing point and the centreline of the two wheels are P1 and P2 respectively. During transmission, the meshing points K1 and K2 move along the meshing line k1k2 to the central section of the tooth width, and the trace of the meshing point on the tooth is an arc k1kk2). When the two meshing points move to the central section of the tooth width, the tooth will exit the meshing and the next pair of teeth will enter the meshing.