High-pressure composite container having gastight nozzle structure

1. A high-pressure composite container having a gastight nozzle structure, the high-pressure composite container comprising:

a metal nozzle formed at a side of an inlet of a plastic liner layer that defines an inner layer of the high-pressure composite container;

a nozzle insert which is inserted into and attached to the metal nozzle in a direction from an inner side of the plastic liner layer to an outer side of the plastic liner layer; and

a nut member fixed to an upper end portion of the nozzle insert,

wherein an elastic member elastically supports the metal nozzle toward the plastic liner layer and is disposed between the metal nozzle and the nut member,

wherein the nozzle insert has screw threads exposed to an outside of the metal nozzle, and the nut member is fastened to the screw threads,

wherein the nozzle insert has a lower flat plate portion disposed at a lower end portion of the nozzle insert and in contact with an inner surface of the plastic liner layer,

wherein the lower flat plate portion is press-fitted into a groove portion defined in the inner surface of the plastic liner layer,

wherein a third sealing element is in contact with the nozzle insert and the inner surface of the plastic liner layer and is attached to an edge portion of an upper end surface of the lower flat plate portion, and

wherein the nozzle insert includes a stepped portion protruding from the edge portion of the upper end surface of the lower flat plate portion, and the third sealing element is attached to the stepped portion.

2. The high-pressure composite container of claim 1 , wherein at least one sealing element for maintaining gastightness is disposed between the nozzle insert and the plastic liner layer.

3. The high-pressure composite container of claim 1 , wherein a first sealing element is in contact with the nozzle insert and the plastic liner layer and is disposed in a groove portion formed in an upper end surface of the lower flat plate portion.

4. The high-pressure composite container of claim 1 , wherein a fourth sealing element is in contact with an upper end surface of the lower flat plate portion and the inner surface of the plastic liner layer, extends up to a portion between an outer surface of the nozzle insert and an inner surface of the metal nozzle and is in contact with the outer surface of the nozzle insert and the inner surface of the metal nozzle.

5. The high-pressure composite container of claim 1 , wherein a second sealing element is in contact with the nozzle insert and the plastic liner layer and is disposed between an outer surface of the nozzle insert and an inlet inner surface of the plastic liner layer.

6. The high-pressure composite container of claim 1 , wherein the elastic member is arranged between the metal nozzle and the nut member in an axial direction of the nozzle insert.