Mechanical monoblock pump, dual-fuel injection system and engine

The invention provides a mechanical unit pump, a dual-fuel injection system and an engine. The mechanical monoblock pump comprises an accelerator rack, an accelerator motor and an accelerator motor, the gear ring is matched with the accelerator rack; the plunger is matched with the gear ring, so that the movement of the accelerator rack drives the plunger to rotate in a plunger sleeve; wherein the plunger head is correspondingly provided with oil control grooves, and the oil control grooves comprise the first oil control groove and the second oil control groove which are adjacently arranged in the extension direction of the plunger; wherein the oil control groove molded line of at least one of the first oil control groove and the second oil control groove comprises a first combustion mode molded line segment and a second combustion mode molded line segment, and the first combustion mode molded line segment and the second combustion mode molded line segment extend discontinuously. 本发明提供机械单体泵、双燃料喷射系统以及发动机。其中，所述