Landing gear main fitting with integral shock absorber

1 . A main fitting, comprising:

an elongate first piston having an internal piston cavity, the first piston having a first end and a second end, a wheel being mounted to the second end of the first piston;

a cylinder having an internal cylinder cavity, the first piston extending through the cylinder cavity and being configured for reciprocating motion between an extended position and a stroked position, the first end of the first piston extending from a first end of the cylinder when first piston is in the stroked position;

a floating second piston slidingly disposed within the piston cavity and dividing the piston cavity into a first chamber and a second chamber, the first chamber containing a first fluid, and the second chamber containing a second fluid, movement of the first piston toward the stroked position compressing the second fluid to produce a spring force that resists movement of the first piston toward the stroked position; and

a rebound assembly mounted to and extending radially outward from the first piston, the rebound assembly dividing a space between the first piston and the cylinder into a third chamber and a fourth chamber, the third chamber being in fluid communication with the first chamber through at least one aperture that extends through the first piston from the first chamber to the third chamber, the third chamber being in fluid communication with the fourth chamber through the rebound assembly,

wherein movement of the cylinder toward the extended position drives a first fluid from the first chamber and the fourth chamber into the third chamber, and movement of the cylinder toward the stroked position drives the first fluid from the third chamber into the first chamber and the fourth chamber, movement of the first fluid into and out of the fourth chamber being limited to first fluid that flows through the rebound assembly.

2 . The main fitting of claim 1 , wherein the first fluid is oil.

3 . The main fitting of claim 1 , wherein the second fluid is a gas.

4 . The main fitting of claim 1 , further comprising a bearing mounted to a second end of the cylinder, wherein the bearing engages the first piston to limit translation of the first piston relative to the cylinder to a longitudinal direction.

5 . The main fitting of claim 4 , wherein the cylinder further comprises an inwardly projecting lip, the bearing being disposed between the lip and a locking ring mounted to the cylinder.

6 . The main fitting of claim 4 , wherein the bearing comprises a dynamic seal that sealingly engages the first piston.

7 . A landing gear assembly for an aircraft, comprising the main fitting according to claim 1 .

8 . The main fitting of claim 1 , wherein the first fluid flows through the rebound assembly at a first rate when the first piston moves toward the stroked position and at a second rate when the first piston moves toward the extended position.

9 . The main fitting of claim 8 , wherein the first rate is greater than the second rate.

10 . The main fitting of claim 8 , wherein the rebound assembly comprises a rebound ring slidably mounted within a groove of a rebound ring retainer, the rebound ring retainer being mounted to the piston.

11 . The main fitting of claim 10 , wherein the rebound ring engages a lower face of the groove when the first piston moves toward the stroked position.

12 . The shocks strut of claim 11 , wherein the rebound ring engages an upper face of the groove when the first piston moves toward the extended position.

13 . A main fitting, comprising:

an elongate first piston having an internal piston cavity, the first piston having a first end and a second end, a wheel being mounted to the second end of the first piston;

a cylinder having an internal cylinder cavity, the first piston extending through the cylinder cavity and being configured for reciprocating motion between an extended position and a stroked position, the first end of the first piston extending from a first end of the cylinder when first piston is in the stroked position;

a floating second piston slidingly disposed within the piston cavity and dividing the piston cavity into a first chamber and a second chamber, the first chamber containing a first fluid, and the second chamber containing a second fluid, movement of the first piston toward the stroked position compressing the second fluid to produce a spring force that resists movement of the first piston toward the stroked position; and

a rebound assembly mounted to and extending radially outward from the first piston, the rebound assembly dividing a space between the first piston and the cylinder into a third chamber and a fourth chamber, the third chamber being in fluid communication with the first chamber through at least one aperture that extends through the first piston from the first chamber to the third chamber, the third chamber being in fluid communication with the fourth chamber through the rebound assembly; and

a bearing mounted to a second end of the cylinder, wherein the bearing engages the first piston to limit translation of the first piston relative to the cylinder to a longitudinal direction,

wherein the cylinder further includes an inwardly projecting lip, the bearing being disposed between the lip and a locking ring mounted to the cylinder, and movement of the cylinder toward the extended position drives a first fluid from the first chamber and the fourth chamber into the third chamber, and movement of the cylinder toward the stroked position drives the first fluid from the third chamber into the first chamber and the fourth chamber, movement of the first fluid into and out of the fourth chamber being limited to first fluid that flows through the rebound assembly.