The pressure angle is a parameter used to describe the meshing mechanical characteristics in gear transmission. If the pressure angle is about 0, it means that the contour curve of the meshing surface is perpendicular to the line of the gear axis. The meshing characteristics of this gear are different from that of ordinary helical gears. When solving the problem of edge grinding eccentricity, the usual method is to design the pressure angle of the gear to 0, which can eliminate the radial force and tangence force caused by edge grinding eccentricity, so as to solve the problem of edge grinding eccentricity. Edge grinding eccentricity refers to problems such as uneven tooth side gap or axial offset during gear processing or use, which will lead to radial force and tangential force when the wheel teeth are meshed, affecting the operating stability and life of gear transmission. By designing a gear with a pressure angle of 0, this instability can be eliminated and the reliability of gear transmission can be improved. It should be noted that the design of a gear with a pressure angle of 0 may have a certain impact on transmission efficiency and bearing capacity, which needs to be considered and weighed according to specific application requirements.