Electric spindle assembly and numerical control machine tool

The utility model provides a motorized spindle assembly and a numerical control machine tool, the motorized spindle assembly includes: a spindle core including a first shaft section and a second shaft section connected in sequence, the outer diameter of the first shaft section being smaller than the outer diameter of the second shaft section; the bearing, the encoder spacer ring and the oil cylinder connecting disc are sequentially installed on the first shaft section in the direction away from the second shaft section, and the second shaft section makes contact with an inner ring of the bearing; the oil cylinder connecting disc comprises a first mounting hole and a second mounting hole which are sequentially communicated in the direction away from the encoder spacer ring, the aperture of the first mounting hole is smaller than that of the second mounting hole, and the first mounting hole is matched with the first shaft section in an inserted mode. The encoder gear is arranged on the oil cylinder connecting d