In actual work, there is often a problem that the working range of the machine tool is not enough. If there is a clever method in the design of the fixture, it can be solved. Our factory has to process a batch of Jiangyan automobile transmission gears. According to the processing procedure, see Figure 1. Since the broaching size is l=139_0~(+0.26)mm, the radius of the inner hole of the disk of the broaching machine L6120 is D/2=100mm. The usual fixture design method is not enough for the working range of the broaching machine. If a large broaching machine (such as L6140) is used, not only the structure of the clamp is large, but the utilization rate of the broaching machine is low. In order to solve this