Ink tank ink adding device of printer

Provided is an ink tank ink adding device of a printer. The ink adding device comprises an ink adding device shell, a pull rod, a needle head, a pull ring, a fixed connecting sleeve, a plastic sealingsleeve, a fastening inserting plate and a positioning clamping ring. A pull rod is connected inside the ink adding device shell; the pull rod slides in the ink adding device shell; fastening protrusion on lower portion of pull rod, a fastening groove is formed in the fastening connecting sleeve; the fastening bulges are matched with the fastening grooves; the outer side of the fastening bulge isconnected with a fastening groove; the outer side of the fastening connecting sleeve is connected with a plastic sealing sleeve; a plurality of dovetail bulges are arranged on the outer side of the fastening connecting sleeve; a plurality of dovetail grooves are formed in the plastic sealing sleeve, the dovetail protrusions are matched with the dovetail grooves, the dovetail protrusions are connected with the dovetail groo