Safe type insulin pen injection needle

Safe type insulin pen injection needle, including needle file, steel needle, needle cap, the needle file comprises adapter sleeve and solid needle post, and the middle part of steel needle is fixed inin the solid needle post, the needle cap is established in the outside of needle file and steel needle with the axle sleeve, and the both ends of needle cap are the open end, back tip at the adaptersleeve is equipped with the spacing face in back, is equipped with the prosodetic planes on needle cap inner wall, installs reset spring between two spacing faces, be equipped with semi -girder in a plurality of in the needle cap, the tip of semi -girder all is connected with an arc piece in every, leaves the interval between the adjacent arc piece, make a plurality of arc pieces constitute with solid needle column sleeve dress complex opening nested structure, be equipped with the cooperation structure of guide way and guide vane between at least one arc piece and solid needle post, be equipped with a plurality of ove