Numerical control milling machine capable of realizing gantry movement under driving of gear rack

The utility model provides a numerical control milling machine capable of realizing gantry movement under the driving of a gear rack. The numerical control milling machine comprises a fixed workbench (1), a Y-direction moving gantry (2), an orthogonal carriage (3) and a Z-direction carriage (4). According to the numerical control milling machine, Y-direction rail bases are arranged on two sides of the fixed workbench; The Y-direction moving gantry can move on the Y-direction rail bases in the left-right direction through being connected with a Y-direction rail pair; the Y-direction moving gantry is driven by meshing of a two-wheel driver and a rack. When the numerical control milling machine works, a workpiece is clamped on the fixed workbench, the Y-direction moving gantry does a Y-direction movement in the left-right direction, the orthogonal carriage does an X-direction movement in the front-back direction, and the Z-direction carriage does a Z-direction movement in the up-down direction, all of which jointly guide a cutting tool at an electric mainshaft to cut and machine the workpiece in a three-dimensional manner; the Y-direction moving gantry is driven by means of seamless meshing of the two-wheel driver and the rack, and the purposes of saving the labor hour, improving the efficiency, reducing the cost and dispensing with a technological seam defect are achieved for numerical control milling of the super-long workpiece by utilizing the technical schemes that the limitation of length of the rack is not needed and the Y-direction operating stroke design length of a lathe can be freely lengthened.