Unequal-pitch variable-rear-angle vertical milling cutter

The invention relates to a three-gear unequal-pitch vertical milling cutter which comprises a blade part and a handle part, wherein the blade part comprises a spiral cutting edge and an end edge. Tooth spacing angles of the unequal-pitch vertical milling cutter are unequal, so that a tool structure is eccentric, and use performance of a tool is restrained, and therefore, required surface quality cannot be achieved. A first rear angle and a second rear angle of each spiral cutting edge of the three-gear unequal-pitch vertical milling cutter are unequal, so that the tool structure of unequal-pitch vertical milling cutter can be optimized, and the eccentric problem of the end surface of the tool can be improved. During rotor rotation, principal axis of inertia and an axis of rotation are guaranteed to be consistent, centrifugal inertia force and inertia force moment of couple generated by mass eccentricity are optimized, so that an inertial force system of a rotor is balanced. Surface quality and dimension preci