The ornamental design for a drillchuckadapter, as shown and described.
FIG. 1 is an elevated view depicting the part of the adapter that receives the square rotor of an impact wrench, the side of which has a set screw as a locking mechanism to lock adapter on said square rotor of the impact wrench thereof.
FIG. 2 is an elevated view of the adapter depicting a threaded shaft that screws into a threaded opening of a drill chuck (not shown). Said threaded shaft having a left-handed threaded bore at it's end which accommodates a left-handed screw. Said left-handed screw prevents loosening of shaft on said drill chuck when reverse drilling is applied thereof; and,
FIG. 3 is a cross sectional view thereof, drawn for clarity of above specification herein.