초록 ▼

A double dam reverse pressure face seal assembly for use in the turbomachine having a tunnel extending through the machine for high pressure air passage therein during normal machine operating has a mating ring positioned annularly respecting the tunnel for flow of lubricating oil generally outwardl

A double dam reverse pressure face seal assembly for use in the turbomachine having a tunnel extending through the machine for high pressure air passage therein during normal machine operating has a mating ring positioned annularly respecting the tunnel for flow of lubricating oil generally outwardly through passageways in the ring and a sealing member biased against an interface surface of the mating ring, the sealing member including a first dam presenting a first contact face to the interface surface of the mating ring, a second dam integral with an outboard of the first dam, presenting a second contact face to the interface surface of the mating ring and a channel between the first and second dams for annularly downward flow of oil leaking inwardly past the second dam towards a channel exit.

대표청구항 ▼

The invention claimed is: 1. A double dam reverse pressure face seal assembly for use in a turbomachine having a tunnel extending therethrough for high pressure air passage therealong during normal machine operation, comprising; a) a mating ring, positioned annularly respecting the tunnel, for flow

The invention claimed is: 1. A double dam reverse pressure face seal assembly for use in a turbomachine having a tunnel extending therethrough for high pressure air passage therealong during normal machine operation, comprising; a) a mating ring, positioned annularly respecting the tunnel, for flow of lubricating oil generally outwardly through passageways in the ring; b) a member biased against an interface surface of the mating ring, the member including: (1) a first dam presenting a first contact face to the interface surface of the mating ring; (2) a second dam integral with and outboard of the first dam, presenting a second contact face to the interface surface of the mating ring; and (3) a channel between the first and second dams for annularly downward flow of oil leaking inwardly past the second dam towards a channel exit. 2. The assembly of claim 1 wherein a) the channel has a bottom that is parallel with the first and second contact faces; b) the first contact face is connected to the channel bottom by a wall that is perpendicular to the first contact face and to the planar bottom; and c) the second contact face is connected to the channel bottom by a wall running diagonally between the second contact face and the channel bottom. 3. The assembly of claim 2 wherein the diagonal wall is at an angle of about 30 degrees relative to the second contact face. 4. The assembly of claim 1 wherein a) the channel has a flat bottom; b) the first contact face is connected to the channel bottom by a wall that is perpendicular to the flat bottom; and c) the second contact face is connected to the channel bottom by a wall running diagonally to the channel bottom. 5. A turbomachine with a tunnel extending therethrough for high pressure air travel through the turbomachine during normal machine operation and including a double dam pressure reversal face seal assembly separating a region of the tunnel having high pressure air traveling therethrough from an adjacent lubricating oil region that is at lower pressure than the air traveling through the tunnel during normal operation, comprising; a) a rotatable apertured mating ring, positioned annularly respecting the tunnel, for flow of lubricating oil from within the tunnel generally outwardly through the apertures to the lubricating oil region; b) a stationary member biased against an interface surface of the mating ring, the member including: (1) a first annular sealing dam presenting a first contact face to the interface surface of the mating ring; (2) a second annular sealing dam outboard of the first annular sealing dam, presenting a second contact face to the interface surface of the mating ring, the second annular sealing dam being integral with the first sealing dam; (3) an annular channel between the first and second annular sealing dams for flow of oil leaking inwardly from the lubricating oil region past the second annular dam downwardly towards a channel exit. 6. The turbomachine of claim 5 in which the mating ring further comprises grooves formed in the mating ring surface facingly contacting the stationary member and positioned to communicate with the annular channel as the mating ring facingly contacts the stationary member, the grooves communicating with an outer edge of the mating ring but terminating short of an inner edge of the mating ring, and being shaped such that a groove inner terminus rotatingly leads a groove outer terminus during mating ring rotation in the course of normal machine operation. 7. The turbomachine of claim 6 wherein portions of the grooves overlie the annular channel when the mating ring facingly contacts the stationary member. 8. The turbomachine of claim 7 wherein the grooves are curved. 9. The turbomachine of claim 7 wherein the grooves are straight. 10. The turbomachine of claim 7 wherein the grooves are spiral shaped. 11. The turbomachine of claim 6 wherein the inner termini of the grooves overlie at least a part of the annular channel when the mating ring facingly contacts the stationary member. 12. The turbomachine of claim 5 wherein a) the channel has a bottom that is parallel with the first and second contact faces; b) the first contact face is connected to the channel bottom by a wall that is perpendicular to the first contact face and to the planar bottom; and c) the second contact face is connected to the channel bottom by a wall running diagonally between the second contact face and the channel bottom. 13. The turbomachine of claim 12 wherein the diagonal wall is at an angle of about 30 degrees relative to the second contact face. 14. The turbomachine of claim 5 wherein a) the channel has a flat bottom; b) the first contact face is connected to the channel bottom by a wall that is perpendicular to the flat bottom; and c) the second contact face is connected to the channel bottom by a wall running diagonally to the channel bottom. 15. A double dam reverse pressure face seal assembly for use in a turbomachine having a tunnel extending therethrough for high pressure air passage therein during normal machine operation, comprising; a) an apertured mating ring having generally radial passageways extending therethrough commencing at the apertures, the ring being positioned annularly respecting the tunnel, for flow of lubricating oil generally outwardly through the radial passageways; and b) a non-rotating member for contacting an interface surface of the mating ring, the member including: (1) a first sealing dam presenting a first contact face to the interface surface of the mating ring; (2) a second sealing dam radially outboard of the first sealing darn, presenting a second contact face to the interface surface of the mating ring, the second sealing dam being integral with the first sealing dam; (3) a channel between and integrally formed with the first and second sealing dams for receiving flow of lubricant oil leaking inwardly past the second sealing dam; (4) the mating ring having grooves formed in the surface facingly contacting the stationary member, the grooves communicating with an outer edge of the mating ring, each groove at least partially overlying the channel when the mating ring facingly contacts the stationary member but terminating short of an inner edge of the mating ring, shaped such that a groove inner terminus leads a groove outer terminus during mating ring rotation in the course of normal machine operation. 16. The double dam reverse pressure face seal assembly of claim 15 wherein the non-rotating member further includes a horizontal groove formed in the second sealing darn, oriented tangentially respecting the channel, of depth greater than the bottom of the channel and positioned at the bottom of the stationery member, to facilitate collective oil flow out of the channel in a horizontal direction tangential to that of rotation of the mating ring during machine operation. 17. The double dam reverse pressure face seal assembly of claim 16 further comprising of wave spring for biasing the non-rotating member against the mating ring. 18. The double dam reverse pressure face seal assembly of claim 16 wherein the non-rotating member is annular. 19. The double dam reverse pressure face seal assembly of claim 18 wherein the non-rotating member is graphite. 20. The double dam reverse pressure face seal assembly of claim 15 wherein the first sealing dam is annular. 21. The double dam reverse pressure face seal assembly of claim 15 wherein the mating ring is metal. 22. The double dam reverse pressure face seal assembly of claim 15 wherein the sealing dam contact faces are parallel one with another. 23. The assembly of claim 15 wherein the first contact face is larger than the second contact face. 24. A double dam reverse pressure face seal assembly for use in a turbomachine having a tunnel extending therethrough for high pressure air passage therein during normal machine operation, comprising; a) an apertured rotatable annular mating ring having generally radial passageways extending therethrough commencing at the apertures, the ring being positioned annularly respecting the tunnel, for flow of lubricating oil generally outwardly through the radial passageways; and b) a non-rotating member for contacting an interface surface of the mating ring, the member including: (1) a first sealing dam presenting a first contact face to the interface surface of the mating ring; (2) a second sealing dam radially outboard of the first sealing dam, presenting a second contact face to the interface surface of the mating ring, the second sealing dam being integral with the first sealing dam; (3) a channel between and integrally formed with the first and second sealing dams for recurrent flow of lubricant oil leaking inwardly; (4) the mating ring having grooves formed in the surface facingly contacting the stationary member, the grooves commencing at an interior portion of the mating ring defining the groove inner terminus such that at least a first portion of each groove proximate the radially inward extremity of a groove overlies at least a portion of the channel and at least a second portion of each groove communicates with an outer edge of the mating ring, thereby defining the groove outer terminus with the grooves being shaped such that a groove inner terminus leads the groove outer terminus as the mating ring rotates during machine normal operation. 25. The assembly of claim 24 wherein a) the channel has a bottom that is parallel with the first and second contact faces; b) the first contact face is connected to the channel bottom by a wall that is perpendicular to the first contact face and to the planar bottom; and c) the second contact face is connected to the channel bottom by a wall running diagonally between the second contact face and the channel bottom. 26. The assembly of claim 25 wherein the diagonal wall is at an angle of about 30 degrees relative to the second contact face. 27. The assembly of claim 25 wherein the grooves are straight. 28. The assembly of claim 25 wherein the grooves are curved. 29. The assembly of claim 25 wherein the grooves are spiral shaped. 30. The assembly of claim 25 wherein the grooves are tangent with an exterior edge of the mating ring. 31. The assembly of claim 25 wherein the first contact face is larger than the second contact face. 32. The assembly of claim 24 wherein a) the channel has a flat bottom; b) the first contact face is connected to the channel bottom by a wall that is perpendicular to the flat bottom; and c) the second contact face is connected to the channel bottom by a wall running diagonally to the channel bottom. 33. A double dam reverse pressure face seal assembly for use in a turbomachine having a tunnel extending therethrough for high pressure air passage therein during normal machine operation, comprising; a) an apertured rotatable annular mating ring having generally radial passageways extending therethrough commencing at the apertures, the ring being positioned annularly respecting the tunnel, for flow of lubricating oil generally outwardly through the radial passageways; and b) a non-rotating member for contacting an interface surface of the mating ring, the member including: (1) a first sealing dam presenting a first contact face to the interface surface of the mating ring; (2) a second sealing dam radially outboard of the first sealing dam, presenting a second contact face to the interface surface of the mating ring, the second sealing dam being integral with the first sealing dam; (3) a channel between and integrally formed with the first and second sealing dams for recurrent flow of lubricant oil leaking inwardly; (4) the mating ring having grooves formed in the surface facingly contacting the stationary member, the grooves extending between an interior portion of the mating ring defining a groove inner terminus such that at least a first portion of each groove proximate the radially inward extremity of a groove overlies at least a portion of the channel and at least a second portion of each groove communicates with an inner edge of the mating ring, with the grooves being shaped such that the second portion of each groove leads a groove inner terminus as the mating ring rotates during normal machine operation. 34. The assembly of claim 33 wherein a) the channel has a bottom that is parallel with the first and second contact faces; b) the first contact face is connected to the channel bottom by a wall that is perpendicular to the first contact face and to the planar bottom; and c) the second contact face is connected to the channel bottom by a wall running diagonally between the second contact face and the channel bottom. 35. The assembly of claim 34 wherein the diagonal wall is at an angle of about 30 degrees relative to the second contact face. 36. The assembly of claim 34 wherein the grooves are straight. 37. The assembly of claim 34 wherein the grooves are curved. 38. The assembly of claim 34 wherein the grooves are spiral shaped. 39. The assembly of claim 34 wherein the grooves are tangent with an interior edge of the mating ring. 40. The assembly of claim 34 wherein the first contact face is larger than the second contact face. 41. The assembly of claim 33 wherein a) the channel has a flat bottom; b) the first contact face is connected to the channel bottom by a wall that is perpendicular to the flat bottom; and c) the second contact face is connected to the channel bottom by a wall running diagonally to the channel bottom. 42. A method for sealing a turbomachine tunnel, having high pressure air passing therethrough during normal operation, against lubricating oil leakage thereinto from an adjacent area that is normally filled with oil mist at pressure substantially lower than the high pressure air, upon a pressure reversal and the adjacent area reaching pressure higher than in the tunnel, comprising the steps of: a) positioning a second face sealing member coaxially radially outboard of and spaced from a conventional stationary first face sealing member, to contact a rotatable mating ring outboard of the conventional stationary face sealing member, with the second face sealing member being longitudinally aligned with but radially spaced from the first sealing member to define an annular closed bottom channel therebetween; and b) providing an outlet from the channel through the second sealing member at the vertical bottom of the second sealing member for passage of oil therethrough from the annular passageway between the sealing members into the oil mist area. 43. The method of claim 42 further comprising a) providing grooves in a surface of the mating ring facingly contacting the first and second face sealing members with the grooves communicating with an outer edge of the mating ring but terminating short of an inner edge of the mating ring and shaped such that a groove inner terminus rotatingly leads a groove outer terminus during mating ring rotation during normal operation and, b) positioning the mating ring so that portions of the grooves overlie an annular channel between first and second face sealing members whereby windage draws oil from the channel through the grooves and outwardly of the outboard one of the face sealing members. 44. The method of claim 43 further comprising providing grooves that are curved. 45. The method of claim 42 further comprising a) providing grooves in a surface of the mating ring facingly contacting the first and second face sealing members with the grooves communicating with an inner edge of the mating ring but terminating short of an outer edge of the mating ring and shaped such that a groove radially inner terminus rotatingly leads a groove radially outer terminus during mating ring rotation during normal operation and, b) positioning the mating ring so that portions of the grooves overlie an annular channel between first and second face sealing members whereby windage draws air from the tunnel through the grooves and into the annular channel between the face sealing members. 46. The method of claim 45 further comprising providing grooves that are straight.