Rapid die changing and aligning device for circular knife

The utility model provides a circular knife quick die changing and aligning device, which relates to the technical field of circular knife die cutting machines and comprises a knife holder, a mounting group frame, fixing blocks and a fixing arm, the fixing blocks are clamped on two sides of the fixing arm, the fixing blocks are L-shaped, the fixing blocks on two sides and the fixing arm jointly form the mounting group frame, a horizontal moving groove is arranged on the front side of the fixing arm, and the horizontal moving groove is provided with a vertical moving groove. The device has the advantages that the die can be accurately aligned after being replaced, the operation is simple and convenient, the time for replacing the cutting die and the material cost are saved, meanwhile, the production efficiency is improved, the cutting dies in different shapes can be rapidly replaced only through simple operation so as to adapt to different die cutting requirements, the alignment device is installed in the U-sh