The top dent is cut off. This phenomenon is called undercutting. The harmful effects of undercutting are as follows: (1) The tooth root becomes weak and easy to bend. (2) Affect the transmission performance of the gear. (3) Affect the continuous transmission and carrying capacity of the gear. Therefore, undercut should be avoided when designing and manufacturing non-standard sprockets. Use a hob to cut the minimum non-standard sprocket Zmin that does not undercut the standard gear. Suzhou non-standard sprocket manufacturers The ratio of the pitch on the index circle to the pi is called the modulus, expressed in m, and the unit is millimeters. The physical meaning of the modulus is that the magnitude of the modulus indicates the amount of power that the gear can transmit. If the modulus of a non-standard sprocket is large, the section will be large, and the teeth will be large, so the power that the gear can transmit will be large; conversely, if the modulus is small, the section will be small, and the teeth will be small, and the power that can be transmitted is also small. The modulus has been standardized, and the standard modulus should be used as much as possible when designing. When the straight line makes pure rolling along the circumference (that is, rolling without sliding, that is, the straight line rotates and tangent on the circumference without interruption), the trajectory curve at any point on the straight line is called the involute of the circle. This circle is called the base circle, and this straight line is called the occurrence line. The tooth profile of the involute gear is a section of the involute. The angle between the force direction line at any point on the tooth profile (perpendicular to the tooth profile surface, tangent to the base circle) and the speed direction line at this point (perpendicular to the radius of rotation of the force point) is called the tooth profile at this point The pressure angle.