Based on the principle of gear machining generating method

a modeling method-variable center distance gear modeling method for variable ratio gear sector profile is put forward.With a given rack parameter and required variable ratio transmission

variable ratio gear sector 3D model could be quickly obtained.An example of designing and calculating variable ratio gear sector profile by the method is given.The analysis shows that the method is concise

practical

and it is suitable for noncircular gear tooth profile design and calculation

especially for the variable ratio steering gear tooth profile design and calculation.