Check joint structure for connection of an air nozzle of a tire and a connector of a connection hose of an air compressor

A check joint structure for a connection of an air nozzle of a tire and a connector of a connection hose of an air compressor, the check joint structure comprising:

• a fitting sleeve, wherein the fitting sleeve has a threaded orifice formed in a first end thereof and having female threads, a through orifice defined on a second end of the fitting sleeve, and a projected shoulder formed on an inner wall of the through orifice, wherein a diameter of the projected shoulder is greater than a diameter of the through orifice, and the threaded orifice is in communication with the through orifice;
• a cylindrical base comprising a cylindrical room, a stepped coupling segment extending along an outer wall of a first end of the cylindrical base, and a conduit defined in the stepped coupling segment and in communication with the cylindrical room, wherein a diameter of the cylindrical room is greater than a diameter of the conduit, and the cylindrical base further includes a first stepped portion formed between the cylindrical room and the conduit;
• a first spring received in the cylindrical room of the cylindrical base, a first end of the first spring abutting against the first stepped portion;
• and
• a valve bolt formed in a columnar shape and comprising a contacting element fit on a first end of the valve bolt, a second end of the valve bolt inserted through the cylindrical room of the cylindrical base and the conduit of the stepped coupling segment to extend out of the stepped coupling segment of the cylindrical base, the contacting element abutting against a second end of the first spring, wherein a first abutting loop is fir on the second end of the valve bolt;
• wherein the first spring pushes the valve bolt so that first abutting loop of the valve bolt contacts with the stepped coupling segment of the cylindrical base and closes the conduit.