Stepped shaft coaxiality measuring jig

The utility model relates to a tool for measuring the coaxiality of a step shaft. The tool comprises a frame body; the two driving rollers are rotationally mounted on the frame body; the clamping assembly comprises a pressing roller, a pull rod and an elastic piece, the pressing roller is located above the driving roller, one end of the pull rod is connected with the pressing roller, the other end of the pull rod penetrates through the frame body, the pull rod can move relative to the frame body, and the elastic piece is arranged on the pull rod in a sleeving mode; the adjusting assembly comprises a pressing plate and a plurality of bolts fixedly connected with the pressing plate, the bolts penetrate through the frame body and are in threaded connection with the frame body, the pull rod penetrates through the pressing plate, and the elastic piece is located between the pressing plate and the pressing roller. The compression degree of the elastic piece can be controlled, so that the elastic force applied to th