Quick diameter changing sleeve

The utility model relates to a quick diameter changing sleeve. The utility model is characterized in that the quick diameter changing sleeve comprises a diameter changing sleeve 1, and a top rod 2 which is inserted in the inner hole on the tail of the diameter changing sleeve 1; the surface of the periphery of the diameter changing sleeve is a Mohs cone, the inner cavity of the diameter changing sleeve is a cylindrical hole / Mohs conical hole, and three channels of grooves which present 120 DEG distribution can be arranged on the part of the Mohs cone. The handle of a cutter can be arranged in the conical hole of the diameter changing sleeve; when the handle of the cutter needs to be replaced, the handle of the cutter can be pushed out through the top rod to avoid the trouble that the original sleeve of the cutter needs to be beaten by the drill key or the hammer when the original sleeve of the cutter is replaced.