Spray gun and nozzle assembly attachment

1. A liquid spray gun nozzle assembly for a gravity-fed liquid spray gun comprising

a coating liquid inlet portion comprising a liquid connector for connection to an external liquid source;

a coating liquid outlet portion comprising a liquid nozzle for spraying a coating liquid fed into the nozzle assembly through the coating liquid inlet portion, the liquid nozzle being disposed along a spray axis;

a coating liquid flow path fluidly connecting the coating liquid inlet portion to the liquid nozzle;

a spray gun connection portion opposite the coating liquid outlet portion adapted to connect the liquid spray gun nozzle assembly to a compatible liquid spray gun body, the spray gun connection portion comprising a nozzle assembly sealing surface adapted to seal the liquid spray gun nozzle assembly to the compatible liquid spray gun body, the nozzle assembly sealing surface comprising first and second sealing members that are each circular and concentric with one another,

wherein upon connection of the liquid spray gun nozzle assembly to the compatible liquid spray gun body, a shaping air zone is concentric with, and isolated between, the first and second sealing members.

2. The liquid spray gun nozzle assembly of claim 1 wherein the first and second sealing members are concentric about the spray axis.

3. The liquid spray gun nozzle assembly of claim 1 wherein, upon connection to the compatible liquid spray gun body, a center air zone is isolated within the second sealing member.

4. The liquid spray gun nozzle assembly of claim 1 wherein the nozzle assembly sealing surface comprises a third sealing member that is circular and concentric with the first and second sealing members.

5. The liquid spray gun nozzle assembly of claim 4 wherein, upon connection to the compatible liquid spray gun body, a center air zone is isolated between the second and third sealing members.

6. The liquid spray gun nozzle assembly of claim 4 wherein, upon connection to the compatible liquid spray gun body, a liquid needle is isolated within the third sealing member.

7. The liquid spray gun nozzle assembly of claim 1 wherein the liquid connector comprises a second connector portion comprising a second connector format comprising a tracking face and a lock structure.

8. The liquid spray gun nozzle assembly of claim 7 further comprising a lid body configured for connection to the liquid connector, the lid body comprising a first connector portion comprising a first connector format configured to connect to the second connector format on the liquid connector for assembly onto the liquid connector.

9. The liquid spray gun nozzle assembly of claim 8 wherein the first connector format comprises a guide surface and a retention structure, wherein the lock structure is configured to selectively interface with the retention structure, and the tracking face is configured to interface with the guide surface.

10. A liquid spray gun assembly comprising

a liquid spray gun body; and

a liquid spray gun nozzle assembly according to claim 1 .

11. The liquid spray gun assembly of claim 10 wherein the liquid spray gun body comprises a captured rotatable locking ring for connection of the liquid spray gun nozzle assembly.

12. The liquid spray gun assembly of claim 11 wherein the captured rotatable locking ring comprises first and second camming lugs adapted to interact with the first and second camming surfaces on the liquid spray gun nozzle assembly.

13. The liquid spray gun assembly of claim 12 wherein the captured rotatable locking ring is rotatable about the spray axis to an assembly position and a locked position, wherein,

in the assembly position, the first and second camming lugs are aligned with the first and second access windows, respectfully, to allow installation or removal of the liquid spray gun nozzle assembly; and

in the locked position, the first and second camming lugs bear against the first and second camming surfaces, respectfully, to lock the liquid spray gun nozzle assembly against the liquid spray gun body.

14. The liquid spray gun assembly of claim 13 wherein rotation of the captured rotatable locking ring from the assembly position to the locked position is less than 180 degrees about the spray axis.

15. The liquid spray gun assembly of claim 14 wherein rotation of the captured rotatable locking ring from the assembly position to the locked position is less than 140 degrees about the spray axis.

16. The liquid spray gun assembly of claim 11 wherein the captured rotatable locking ring is installable onto the liquid spray gun body by pushing the captured rotatable locking ring along the spray axis, and is removable from the liquid spray gun body by pulling along the spray axis.

17. The liquid spray gun assembly of claim 16 wherein the captured rotatable locking ring is rotatable about the spray axis to an assembly position and a locked position, wherein the captured rotatable locking ring is installable onto and removable from the liquid spray gun body when rotated to the assembly position, but not removable when rotated to the locked position.

18. The liquid spray gun assembly of claim 16 wherein the captured rotatable locking ring is installable and removable from the liquid spray gun body via a snapping feature.

19. The liquid spray gun assembly of claim 16 wherein the captured rotatable locking ring is installable and removable from the liquid spray gun body without the use of a tool.

20. A method of using a liquid spray gun assembly according to claim 10 comprising installing the liquid spray gun nozzle assembly onto the liquid spray gun body.