Mechanical bone extractor with stop unit

The invention relates to the class of bone breakers, bone drills or bone chisels and trepans, in particular to a mechanical bone extractor with a stop unit. The technical scheme includes that the mechanical bone extractor comprises a motor head (7), the motor head (7) is connected with a bone extracting cylinder (2) through a drill pipe (5), and cutting teeth (3) are formed at the front end of the bone extracting cylinder (2). The mechanical bone extractor is characterized in that a stop cylinder (1) in the shape corresponding to the inner diameter of the bone extracting cylinder (2) is movably mounted in the bone extracting cylinder (2), bottom holes (4) are arranged at the back end of the bone extracting cylinder (2), and the mechanical bone extractor further comprises a cylindrical ejector needle (6) with the diameter smaller than that of each bottom hole (4). The mechanical bone extractor with the stop unit has the advantages that bones can be extracted more quickly and accurately, bone extracting efficiency is increased while wound of patients is reduced since the mechanical bone extractor can acquire accurate bone mass and simultaneously have a stop function.