High-pressure rotating sealing coupling with continuous expandable ring

1. A high-pressure rotating sealing coupling with a continuous expandable ring ( 1 ), comprising:

at least one male hydraulic connector ( 2 ) forming an integral part of a male supply body ( 3 ), or at least one female hydraulic connector ( 4 ), which forms an integral part of a female supply body ( 5 ), said connectors ( 2 , 4 ) being coaxial whilst the male hydraulic connector ( 2 ) is accommodated within the female hydraulic connector ( 4 ) and can rotate relative to the female hydraulic connector ( 4 ) along a longitudinal axis common to the two aforesaid connectors ( 2 , 4 ), while the male hydraulic connector ( 2 ) has a male connection face ( 6 ) which faces a female connection face ( 7 ) located on the female hydraulic connector ( 4 ), said connection faces ( 6 , 7 ) being shapes of revolution;

at least one male connector internal fluid duct ( 8 ) arranged inside the male hydraulic connector ( 2 ), in which duct a fluid ( 16 ) can circulate and of which one end leads into a communication chamber ( 10 ) arranged in the female supply body ( 5 ) or the male supply body ( 3 );

at least one female connector internal fluid duct ( 9 ) arranged inside the female hydraulic connector ( 4 ), in which duct the fluid ( 16 ) can circulate and of which one end leads into the communication chamber ( 10 );

at least one female cylindrical sealing section ( 11 ) arranged in the female connection face ( 7 ), or a male cylindrical sealing section ( 21 ) arranged on the male connection face ( 6 );

at least one non-expandable sealing ring ( 42 ) mounted around the male hydraulic connector ( 2 ) and which can slide along the male hydraulic connector ( 2 ), said ring ( 42 ) being accommodated with little play in the cylindrical female sealing section ( 11 ), or at least one non-expandable sealing ring ( 42 ) accommodated in the female hydraulic connector ( 4 ) and which can move in translation longitudinally within the female hydraulic connector ( 4 ), said ring ( 42 ) being mounted with little play around the cylindrical male sealing section ( 21 );

at least one continuous expandable ring ( 13 ) of continuous annular form, inserted axially between the non-expandable sealing ring ( 42 ) and a ring annular bearing shoulder ( 14 ) arranged or connected on the male connection face ( 6 ) or on the female connection face ( 7 ), said continuous ring ( 13 ) comprising either an expandable ring inner cylindrical face ( 15 ) that can be subjected to the pressure of the fluid ( 16 ) contained in the communication chamber ( 10 ) via a pressure transmission channel ( 12 ) such that an expandable ring outer cylindrical face ( 17 ) located on said continuous ring ( 13 ) comes into contact over the entire outer circumference thereof with the cylindrical female sealing section ( 11 ), or an expandable ring outer cylindrical face ( 17 ) that can be subjected to the pressure of the fluid ( 16 ) contained in the communication chamber ( 10 ) via a pressure transmission channel ( 12 ) such that an expandable ring inner cylindrical face ( 15 ) located on said continuous ring ( 13 ) comes into contact over the entire inner circumference thereof with the cylindrical male sealing section ( 21 ), said continuous expandable ring ( 13 ) comprising an axial face on a non-expandable ring ( 18 ) side held directly or indirectly in tight contact with the non-expandable sealing ring ( 42 ), and an axial face on a bearing shoulder ( 19 ) side held directly or indirectly in tight contact with the ring annular bearing shoulder ( 14 ); and

at least one non-expandable ring spring ( 20 ), which tends to draw the non-expandable sealing ring ( 42 ) close to the ring annular bearing shoulder ( 14 ) and to axially compress the continuous expandable ring ( 13 ).

2. The sealing coupling according to claim 1 , wherein an axial length portion of the expandable ring inner cylindrical face ( 15 ) closer to the ring annular bearing shoulder ( 14 ) on average has a diameter smaller than an axial length portion of said cylindrical face ( 15 ) closer to the non-expandable sealing ring ( 42 ), whereas the expandable ring outer cylindrical face ( 17 ) has approximately a same diameter over an entire axial length thereof.

3. The sealing coupling according to claim 1 , wherein an axial length portion of the expandable ring outer cylindrical face ( 17 ) closer to the ring annular bearing shoulder ( 14 ) on average has a diameter greater than an axial length portion of said cylindrical face ( 17 ) closer to the non-expandable sealing ring ( 42 ), whereas the expandable ring inner cylindrical face ( 15 ) has approximately a same diameter over a entire axial length thereof.

4. The sealing coupling according to claim 1 , wherein an outer circumferential contact line ( 22 ) is arranged in a protruding manner on the expandable ring outer cylindrical face ( 17 ), said line ( 22 ) being eccentric over the axial length of the continuous expandable ring ( 13 ) in the direction of the non-expandable sealing ring ( 42 ), such that a long slope of gradual incline ( 23 ) is formed from said line ( 2 ) oriented in the direction of the ring annular bearing shoulder ( 14 ), whereas a short slope of steep incline ( 24 ) is formed from said line ( 22 ) oriented in the direction of the non-expandable sealing ring ( 42 ).

5. The sealing coupling according to claim 1 , wherein an inner circumferential contact line ( 25 ) is arranged in a protruding manner on the expandable ring inner cylindrical face ( 15 ), said line ( 25 ) being eccentric over the axial length of the continuous expandable ring ( 13 ) in the direction of the non-expandable sealing ring ( 42 ), such that a long slope of gradual incline ( 23 ) is formed from said line ( 2 ) oriented in the direction of the ring annular bearing shoulder ( 14 ), whereas a short slope of steep incline ( 24 ) is formed from said line ( 22 ) oriented in the direction of the non-expandable sealing ring ( 42 ).

6. The sealing coupling according to claim 1 , wherein the axial face on the non-expandable ring ( 18 ) side or the axial face on the bearing shoulder ( 19 ) side comprises an axial annular protrusion ( 26 ).

7. The sealing coupling according to claim 1 , wherein the female supply body ( 5 ) or the male supply body ( 3 ) forms a hydraulic pump rotor ( 27 ) for a hydraulic piston pump ( 32 ), said rotor ( 27 ) comprising at least one hydraulic cylinder in which a hydraulic piston ( 29 ) can move in translation longitudinally in an alternating manner, tightly so as to form with said cylinder ( 28 ) a pump oil chamber ( 30 ) of variable volume that can aspirate or deliver the fluid ( 16 ), said oil chamber ( 30 ) being connected to the communication chamber ( 10 ) by the female connector internal fluid duct ( 9 ) or the male connector internal fluid duct ( 8 ) via a pump delivery valve ( 31 ), the pump delivery valve ( 31 ) allowing the fluid ( 16 ) to exit the pump oil chamber ( 30 ) in order to pass into the communication chamber ( 10 ), but not the other way round, whereas the pump oil chamber ( 30 ) also has a pump intake valve ( 33 ), which allows the fluid ( 16 ) to enter said oil chamber ( 30 ), but not to exit therefrom.

8. The sealing coupling according to claim 1 , wherein the male hydraulic connector ( 2 ) is held centered in the female hydraulic connector ( 4 ) and is hinged relative thereto by at least one connector bearing ( 34 ).

9. The sealing coupling according to claim 1 , wherein the male connector internal fluid duct ( 8 ) or the female connector internal fluid duct ( 9 ) is connected to a connection body ( 35 ) by means of at least one outer connection duct ( 36 ), which is secured by a first end to the male supply body ( 3 ) or to the female supply body ( 5 ) by means of a supply body tight ball joint ( 37 ) and by a second end to the connection body ( 35 ) by means of a connection body tight ball joint ( 38 ).

10. The sealing coupling according to claim 9 , wherein the supply body tight ball joint ( 37 ) or the connection body tight ball joint ( 38 ) is formed by a sealing ball carrier in the form of a truncated sphere ( 39 ) located on the outer connection duct ( 36 ), said ball carrier ( 39 ) resting on a sealing ball seat ( 40 ) arranged either in the male supply body ( 3 ) or in the female supply body ( 5 ) with regard to the first end of the outer connection duct ( 36 ) or in the connection body ( 35 ) with regard to the second end of said outer duct ( 36 ).

11. The sealing coupling according to claim 10 , wherein the sealing ball carrier in the form of the truncated sphere ( 39 ) is either mounted fixedly on the outer connection duct ( 36 ), or with the outer connection duct ( 36 ) forms a tight sliding connection or a tight pivoting and sliding connection.

12. The sealing coupling according to claim 10 , wherein the sealing ball carrier in the form of a truncated sphere ( 39 ) is directly or indirectly held in contact with the sealing ball seat ( 40 ) by a ball carrier spring ( 41 ).

13. The sealing coupling according to claim 1 , wherein a longitudinal end of the non-expandable sealing ring ( 42 ), which is held in tight contact with the axial face on the non-expandable ring ( 18 ) side has a protruding truncated cone or truncated sphere profile.