Adjustable grinding wheel dressing machine capable of performing crankshaft journal under cutting

The invention provides an adjustable grinding wheel dressing machine capable of performing crankshaft journal under cutting. The adjustable grinding wheel dressing machine comprises a horizontal bottom plate, skidproof stand bars, a waste residue storing disk, a longitudinal fixing rack, a rectangular mounting frame, a horizontal fixing rack, a buffering clip rack structure, a tool storing frame,a trimming motor, a plane trimming wheel, an electric rotating wheel rack structure, an adjustable clip rack structure, a waste material storing rack structure and a power supply switch, wherein the skidproof stand bars are in glued joint to four corners of the lower part of the horizontal bottom plate; and the waste residue storing disk is placed on the left side of the middle and upper part of the horizontal bottom plate. According to the adjustable grinding wheel dressing machine disclosed by the invention, locking nuts are respectively arranged on the rear side of a flank fixing plate andthe front side of the flan