Lathe modification structure used for machining chain way chain pins

The utility model provides a lathe modification structure used for machining chain way chain pins. The lathe modification structure used for machining the chain way chain pins comprises a lathe body and a three-claw chuck, wherein a ball screw parallel with the axis of the three-claw chuck is arranged below the three-claw chuck, a tool rest is installed on the ball screw, a first servo motor is arranged at one end of the ball screw, a tool changing device and a second servo motor are arranged on the tool rest, and a third servo motor used for driving the three-claw chuck to rotate and a control system used for controlling the working time sequence of the first servo motor, the second servo motor and the third servo motor are further installed on the lathe body. The lathe modification structure effectively improves the accuracy of a lathe by replacing a trapezoidal screw of an existing ordinary lathe with the ball screw, is provided with the first servo motor and the second servo motor to replace an original manual operating device, is provided with the third servo motor to replace an original gear manual gearbox, and is high in automation degree.