Protection device for machining cutter shaft

The utility model discloses a protection device for a machining cutter shaft. The cutter comprises a cutter head, a cutter shaft and a cutter seat, the tool bit is mounted on the tool apron through atool shaft; limiting blocks are arranged on the outer sides of the tool bases. Bearings are mounted at the bottoms of the limiting blocks; an inner ring of the bearing is in interference fit with thetool apron; a clamping ring is mounted on the outer ring of the bearing in an interference fit manner; a plurality of support lugs are uniformly distributed on the outer side of the clamping ring; anopen clamping groove is formed in the middle of each supporting lug, a protective cover is installed on each supporting lug, an adjusting groove corresponding to the thickness of each supporting lug is formed in the protective cover in the vertical direction and is in sliding fit with the supporting lugs through the adjusting grooves, clamping teeth are arranged on the two sides of each adjustinggroove, and locking rings ar