FLEX JOINT HAVING LINER WITH ARTICULATED JOINT

1 . A flex joint comprising:

a bellows; and

a liner system disposed in the bellows, the liner system including two generally cylindrical liner pieces, the two generally cylindrical liner pieces being connected to each other in an articulated joint, wherein one of the two generally cylindrical liner pieces defines a ball joint end and the other of the two generally cylindrical liner pieces defines a socket joint end, the ball joint end being engaged with the socket joint end to form a ball and socket joint as the articulated joint.

2 . The flex joint as recited in claim 1 , further comprising an additional generally cylindrical liner piece connected in an axial sliding joint with one of the two generally cylindrical liner pieces.

3 . The flex joint as recited in claim 2 , wherein the bellows comprises first and second bellows sections, wherein one of the two generally cylindrical liner pieces is primarily disposed within the first bellows section, and the other of the two generally cylindrical liner pieces is primary disposed within the second bellows section.

4 . The flex joint as recited in claim 3 , further comprising first and second linkages connected, respectively, with the first and second bellows sections.

5 . The flex joint as recited in claim 4 , further comprising a damper connected between the first and second linkages.

6 . The flex joint as recited in claim 1 , wherein the bellows comprises first and second bellows sections, wherein one of the two generally cylindrical liner pieces is primarily disposed within the first bellows section, and the other of the two generally cylindrical liner pieces is primary disposed within the second bellows section.

7 . The flex joint as recited in claim 6 , further comprising first and second linkages connected, respectively, with the first and second bellows.

8 . The flex joint as recited in claim 7 , further comprising a damper connected between the first and second linkages.

9 . A rocket engine comprising:

a combustion chamber;

a nozzle in fluid communication with the combustion chamber; and

at least one propellant duct, the at least one propellant duct including a flex joint, the flex joint including:

a bellows, and

a liner system disposed in the bellows, the liner system including two generally cylindrical liner pieces, the two generally cylindrical liner pieces being connected to each other in an articulated joint, wherein one of the two generally cylindrical liner pieces defines a ball joint end and the other of the two generally cylindrical liner pieces defines a socket joint end, the ball joint end being engaged with the socket joint end to form a ball and socket joint as the articulated joint.

10 . The rocket engine as recited in claim 9 , further comprising an additional generally cylindrical liner piece connected in an axial sliding joint with one of the two generally cylindrical liner pieces.

11 . The rocket engine as recited in claim 10 , wherein the bellows comprises first and second bellows sections, wherein one of the two generally cylindrical liner pieces is primarily disposed within the first bellows section, and the other of the two generally cylindrical liner pieces is primary disposed within the second bellows section.

12 . The rocket engine as recited in claim 11 , further comprising first and second linkages connected, respectively, with the first and second bellows sections.

13 . The rocket engine as recited in claim 12 , further comprising a damper connected between the first and second linkages.

14 . The rocket engine as recited in claim 9 , wherein the bellows comprises first and second bellows sections, wherein one of the two generally cylindrical liner pieces is primarily disposed within the first bellows section, and the other of the two generally cylindrical liner pieces is primary disposed within the second bellows section.

15 . The flex joint as recited in claim 14 , further comprising first and second linkages connected, respectively, with the first and second bellows.

16 . The flex joint as recited in claim 15 , further comprising a damper connected between the first and second linkages.

17 . A flex joint comprising:

a bellows; and

a liner system including:

a first liner piece disposed in the bellows, the first liner piece having a first liner spherical joint end,

a second liner piece disposed in the bellows, the second liner piece having a second liner cylindrical end, and

an intermediate liner piece joining the first and second liner pieces, the intermediate liner piece having an intermediate liner spherical joint end and an intermediate liner cylindrical end, the intermediate liner spherical joint end conforming with the first liner spherical joint end, and the intermediate liner cylindrical end conforming with the second liner cylindrical end.

18 . The flex joint as recited in claim 17 , wherein the intermediate liner cylindrical end is slidable with respect to the second liner cylindrical end.

19 . The flex joint as recited in claim 17 , wherein one of the intermediate liner spherical joint end and the first liner spherical joint end includes a convex spherical surface, and the other of the intermediate liner spherical joint end and the first liner spherical joint end includes a concave spherical surface.

20 . The flex joint as recited in claim 17 , wherein each of the first liner piece, the second liner piece, and the intermediate liner piece has a cylindrical section with a constant circular cross-section.