Types of profile modification for involute spur gear drive system

There are many types of profile modification curves. According to the different functional forms of the modification quantity with respect to the length of engagement line, the modification types can be divided into: linear modification, conic modification, exponential modification, high-order modification and triangular modification.

There are many methods to determine the profile modification curve, and there are great differences among them.

In previous studies, the optimal shape curve is usually given based on static characteristics.In the research and optimization design of gear profile modification based on the dynamic characteristics of gear transmission system, the two most common modification methods are linear and parabolic.

The study considers three types of modification: linear, conic and exponential, and expresses them in a general form.

In the formula, A and B are the coefficients related to the type of modification, and the boundary condition of the amount of modification must be satisfied between them, i.e., a+b=1.When a=1 and b=0, the modification type is linear; when 1<n<2 and a=0, the modification type is exponential; when n=2 and a is not equal to 1, the modification type is conic, where a=0 and b=1, the modification type is also called parabolic.