Turbine engine comprising a floating bearing for guiding a shaft of the turbine engine

1. A turbine engine comprising:

a shaft;

a bearing for rotatably guiding the shaft about an axis of the turbine engine, the bearing comprising a first, radially inner ring and a second, radially outer ring enclosing a rolling member, wherein the first ring is floatingly mounted on the shaft via a fluid damping film so as to damp orientation defects of the shaft during operation thereof; and

upstream and downstream sealing segments configured to form a damping chamber which is delimited radially by the first ring and the shaft and longitudinally by the upstream and downstream sealing segments, the damping chamber containing the fluid damping film,

wherein the shaft comprises a main annular trough formed radially in an inner surface of the shaft, an auxiliary annular trough formed radially in an inner surface of the main trough, a first hole which connects the auxiliary trough to an outer surface of the shaft, and a second hole which connects the main trough to the outer surface of the shaft,

wherein the first ring comprises an upstream annular groove and a downstream annular groove, and

wherein the auxiliary annular trough is in fluid communication with the damping chamber via the first hole, and the main annular trough is in fluid communication with one of the upstream and downstream annular grooves via the second hole.

2. A turbine engine according to claim 1 , wherein the shaft comprises an upstream annular compartment which houses the upstream sealing segment, and a downstream annular compartment which houses the downstream sealing segment.

3. A turbine engine according to claim 2 , wherein the first ring comprises an outer surface turned towards a rolling member of the bearing and an inner surface opposite the outer surface, the inner surface of the first ring comprises the upstream annular groove and the downstream annular groove, and the inner surface of the first ring extends between the upstream and downstream annular grooves and is solid, the upstream groove of the first ring is further upstream than the upstream annular compartment housing the upstream sealing segment, and the downstream groove of the first ring is further downstream of the downstream annular compartment housing the downstream sealing segment.

4. A turbine engine according to claim 3 , wherein the first ring comprises:

at least one internal longitudinal channel extending in the first ring,

first channels connecting the longitudinal channel to the inner surface of the first ring, and

second channels connecting the longitudinal channel to the outer surface of the first ring.

5. A turbine engine according to claim 4 , wherein the first channels discharge into at least one of the upstream and downstream annular grooves.

6. A turbine engine according to claim 3 , wherein the first ring comprises at least connecting channels extending diagonally in relation to a transverse plane defined in relation to the axis of the turbine engine, the connecting channels connecting the inner surface of the first ring to the outer surface thereof.

7. A turbine engine according to claim 1 , wherein, the turbine engine comprises a low-pressure turbine shaft and a high-pressure turbine shaft, the first ring is an inner ring of an intershaft bearing mounted on the high-pressure turbine shaft.

8. A turbine engine according to claim 1 , wherein the shaft comprises:

at least one upstream radial through-holes aligned with the upstream annular groove of the first ring,

at least one downstream radial through-holes aligned with the downstream annular groove, and

at least one central radial through-holes discharging into the damping chamber in order to supply channels of the first ring, to distribute a flow of lubrication oil on an outer surface of the first ring to lubricate cages and rolling members, and to supply the damping chamber.

9. A method for supplying lubrication oil to a turbine engine including a shaft, a bearing for rotatably guiding the shaft about an axis of the turbine engine, the bearing including a first, radially inner ring and a second, radially outer ring enclosing a rolling member, the first ring being mounted outside the shaft and including channels for lubricating the rolling member, a damping chamber being defined radially between the first ring and the shaft and longitudinally by upstream and downstream sealing segments,

the shaft comprises a main annular trough formed radially in an inner surface of the shaft, an auxiliary annular trough formed radially in an inner surface of the main trough, a first hole which connects the auxiliary trough to an outer surface of the shaft, and a second hole which connects the main trough to the outer surface of the shaft, the first ring comprises an upstream annular groove and a downstream annular groove, and the auxiliary annular trough is in fluid communication with the damping chamber via the first hole, and the main annular trough is in fluid communication with one of the upstream and downstream annular grooves via the second hole,

the method, when the turbine engine is switched on, comprising:

supplying a flow of lubrication oil to the damping chamber via the first hole to form a fluid damping film between the first ring and the shaft; then

supplying the flow of lubrication oil to the lubrication channels of the rolling member.

10. A turbine engine comprising:

a shaft;

a bearing for rotatably guiding the shaft about an axis of the turbine engine, the bearing comprising a first, radially inner ring and a second, radially outer ring enclosing a rolling member, wherein the first ring is floatingly mounted on the shaft via a fluid damping film so as to damp orientation defects of the shaft during operation thereof; and

upstream and downstream sealing segments configured to form a damping chamber which is delimited radially by the first ring and the shaft and longitudinally by the upstream and downstream sealing segments, the damping chamber containing the fluid damping film,

wherein the shaft comprises an upstream annular compartment which houses the upstream sealing segment, and a downstream annular compartment which houses the downstream sealing segment, and

wherein, the first ring comprises an outer surface turned towards the rolling member of the bearing and an inner surface opposite the outer surface, the inner surface of the first ring comprises an upstream annular groove and a downstream annular groove, and the inner surface of the first ring extends between the upstream and downstream annular grooves and is solid, the upstream groove of the first ring is further upstream than the upstream annular compartment housing the upstream sealing segment, and the downstream groove of the first ring is further downstream of the downstream annular compartment housing the downstream sealing segment.