APPARATUS FOR OIL LUBRICATION OF A ROTATIONALLY FIXED CONNECTION BETWEEN TWO SHAFTS
20230025047 · 2023-01-26
Inventors
Cpc classification
F02C7/36
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2260/36
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2240/61
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C7/06
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2250/291
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2260/98
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C7/28
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F02C7/06
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C7/28
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
An apparatus for oil lubrication of a rotationally fixed connection between two shafts. A first shaft engages with a hollow region of the second shaft. The shafts are operatively connected to each other in a form-fitting manner in the overlapping region. Oil is introduced into a first chamber in the hollow region, which chamber is connected to a second chamber in the hollow region. The second chamber is connectable to a third chamber is arranged in the overlapping region. The fluidic connection between the second chamber and the third chamber is separated above a defined oil volume in the second chamber and above a rotational speed threshold of the shafts via a sealing element. The sealing element is reversibly deformable by the oil volume in the second chamber and the centrifugal force acting thereon and, in the deformed state, seals the connection between the second and third chambers.
Claims
1. An apparatus for oil lubrication of a rotationally fixed connection between two shafts, wherein a first shaft engages with a shaft region in a hollow-cylindrical shaft region of the second shaft, and the shafts are operatively connected to each other in a form-fitting manner in the overlapping region, wherein oil can be introduced in the axial direction through a central opening into a first chamber in the hollow-cylindrical region of the first shaft, which chamber is fluidically connected to a second chamber in the hollow-cylindrical region of the second shaft, wherein the second chamber is fluidically connectable to a third chamber, wherein the third chamber is arranged in the overlapping region between the first shaft and the second shaft, wherein the fluidic connection between the second chamber and the third chamber is separated above a defined oil volume in the second chamber and above a rotational speed threshold of the shafts via a sealing element which is reversibly deformable at least in regions by the oil volume in the second chamber and the centrifugal force acting thereon and, in the deformed state, seals the connection between the second chamber and the third chamber in relation to the second chamber.
2. The device according to claim 1, wherein the inside diameter of the central opening, the outside diameter of the first chamber, the outside diameter of the second chamber and the connections between the chambers are coordinated with one another in such a manner that, above the rotational speed threshold of the shafts, a defined oil level in each case arises in the first chamber and in the second chamber, and the sealing element is reversibly deformed at least in regions by the oil volume in the second chamber and the centrifugal force acting thereon and seals the connection between the second chamber and the third chamber.
3. The device according to claim 1, wherein the sealing element has an annular disk region which projects radially inwards into the second chamber and on which the oil volume present in the second chamber is supported in the axial direction, wherein at least one free inner edge region of the annular disk region is pressed by the oil volume in the second chamber in the axial direction against a free shaft end of the first shaft or against a boundary wall of the hollow-cylindrical region, said boundary wall bounding the second chamber and the third chamber, and seals the connection between the second chamber and third chamber if an oil volume above the defined oil volume is present in the second chamber and the rotational speed of the shafts is greater than the rotational speed threshold.
4. The device according to claim 3, wherein the inner edge region of the annular disk region of the sealing element is formed on the side facing the shaft end of the first shaft with a sealing bead which extends in the circumferential direction of the sealing element.
5. The device according to claim 1, wherein the connection between the first chamber and the second chamber comprises at least one passage opening, wherein the passage opening runs from the outside diameter of the first chamber in the direction of the second chamber or in the radial direction between the outside diameter of the first chamber and the inside diameter of the central opening in the direction of the second chamber.
6. The device according to claim 5, wherein the passage opening is provided in a radial wall region which separates the first chamber from the second chamber in the axial direction of the shafts.
7. The device according to claim 6, wherein the radial wall region is formed with a preferably central opening in the radial direction of the shafts, the central opening connecting the first chamber and the second chamber.
8. The device according to claim 1, wherein the inside diameter of the annular disk region of the sealing element at least approximately corresponds to the inside diameter of the central opening of the first chamber and is preferably smaller than the inside diameter of the central opening.
9. The device according to claim 1, wherein the chambers are bounded at least by a hollow-cylindrical component which is arranged in the hollow-cylindrical region of the second shaft and is connected fixedly to the second shaft and is preferably rotationally symmetrical.
10. The device according to claim 9, wherein the sealing element is formed integrally with the hollow-cylindrical component.
11. The device according to claim 1, wherein the sealing element lies in the axial direction on an annular contact surface of an axial step of the second shaft, wherein the contact surface of the step is spaced apart in the axial direction from the shaft end of the first shaft, and wherein the inside diameter of the contact surface is greater than the inside diameter of the annular disk region of the sealing element.
12. The device according to claim 1, wherein the sealing element comprises at least one flat sealing disk region which is arranged between an end face of the hollow-cylindrical component and the contact surface of the step.
13. The device according to claim 1, wherein the sealing element is arranged with a radial outer region in an inner groove of the hollow-cylindrical component and is connected fixedly to the hollow-cylindrical component.
14. The device according to claim 1, wherein the hollow-cylindrical component is designed in two parts, wherein the parts of the hollow-cylindrical component are arranged in the hollow-cylindrical region of the second shaft in a manner spaced apart from each other in the axial direction of the shafts, and, between the parts of the hollow-cylindrical component, the second chamber is bounded by the parts.
15. The device according to claim 1, wherein the sealing element is supported with a radially outer region on the second shaft, with an axial region on the shaft end of the first shaft, and with a further axial region on the hollow-cylindrical component, wherein the annular disk region of the sealing element can be placed by the oil volume in the second chamber against the shaft end of the first shaft in a sealing manner and separates a connection between the second chamber and the third chamber, which connection runs through the axial region of the sealing element.
Description
[0037] In the figures:
[0038]
[0039]
[0040]
[0041]
[0042]
[0043]
[0044]
[0045]
[0046]
[0047]
[0048]
[0049]
[0050]
[0051]
[0052]
[0053]
[0054]
[0055]
[0056]
[0057] In the embodiment of the gas turbine engine 1 according to
[0058] In contrast thereto, the auxiliary unit gearbox 13 with the auxiliary units 16 is arranged in the radial direction between the bypass channel 2 and the engine core 5, in the case of the gas turbine engine 1 according to
[0059]
[0060] An oil feed unit 26 is provided via which oil is introduced or injected or even sprayed, depending on the application, into a hollow-cylindrical region 27 of the shaft 22, which is the drive shaft of the auxiliary unit gearbox 13. An oil divider 28 is inserted here into the hollow-cylindrical region 27 of the shaft 22, the oil divider being designed as a substantially rotationally symmetrical, hollow-cylindrical component and bounding a first chamber 29 and a second chamber 30. The oil divider 28 is formed with a central opening 31 through which oil is introduced here in the form of an oil jet by the oil feed unit 26 into the first chamber 29.
[0061] An inside diameter Di31 of the central opening 31 of the oil divider 28 or of the first chamber 29 is provided in such a manner that, during operation of the gas turbine engine 1, a defined oil volume or what is referred to as a dynamic oil level 32 arises in the first chamber 29 and in the second chamber 30 above a defined rotational speed threshold of the shafts 22 and 23. The first chamber 29 and the second chamber 30 are connected to each other via connecting passages or connecting bores 33 which lead through a radial wall region 70 between the chambers 29 and 30. Oil is introduced from the first chamber 29 via the connecting bores 33 into the second chamber 30 when the dynamic oil level 32 in the first chamber 29 reaches the radial level of the connecting bores 33. The oil volume present in each case in the chambers 29 and 30 is applied in the manner illustrated in
[0062] In the last-mentioned operating state of the apparatus 20, the oil volume present in the second chamber 30 in conjunction with the centrifugal force acting thereon has the effect that a sealing element 36, which is formed integrally with the oil divider 28 in a region facing the shaft 23, is reversibly deformed in the manner shown specifically in
[0063] The inner edge region 42 of the sealing element 36 is formed on the side facing the shaft end 44 of the shaft 23 with a sealing bead or sealing lip 45 which constitutes an enlarged material region of the sealing element 36. As large a sealing surface as possible is achieved in the circumferential direction and in the radial direction between the sealing element 36 and the shaft end 44 or the end face 43 of the shaft end 44, as is a high sealing action, by means of the sealing bead 45.
[0064]
[0065] The static oil level 46 in the first chamber 29 depends on the inside diameter Di31 of the central opening 31 through which the oil then immediately flows out of the first chamber 29 into the hollow-cylindrical region 27 of the shaft 22. The height of the static oil level 46 corresponds to the radial height from the lower region of the first chamber 29 as far as the lower edge of the central opening 31.
[0066] The static oil level 47 arises in the second chamber 30 during the discharge operation of the gas turbine engine 1 owing to the fact that the oil flows out of the second chamber 30 counter to the resistance of the oil volume present in the first chamber 29 and, given a corresponding static filling level, also via a central venting bore 48 into the first chamber 29. The oil therefore flows out of the second chamber 30 substantially more slowly than out of the first chamber 29, and therefore the static oil level 47 is higher, at least for a limited period of time, than the static oil level 46 in the first chamber 29.
[0067] During normal operation of the gas turbine engine 1, air is conducted out of the second chamber 30 into the first chamber 29 via the venting bore 48 in order to avoid an undesirable increase in pressure in the second chamber 30. Such an increase in pressure in the second chamber would otherwise prevent oil from being admitted from the first chamber 29 via the venting bore 33 into the second chamber 30 and impair the sealing action, described in more detail above, of the sealing element 36 due to too low an oil level 32 in the second chamber 30.
[0068] Owing to the decreasing rotational speed of the shafts 22, 23 and the resultant reduction in centrifugal force, the oil pressure which bears in the axial direction against the sealing element 36 also decreases. Since the sealing element 36 is designed with corresponding spring elasticity and a corresponding restoring behavior which counteracts the oil pressure in the axial direction of the shafts 22 and 23, the free inner edge region 42 of the sealing element 36 springs back under the rotational speed threshold of the shafts 22 and 23 into the position illustrated in
[0069] As long as the static oil level 47 in the second chamber 30 lies above the lower region of the free inner edge region 42 of the sealing element 36, oil flows out of the second chamber 29 via the free inner edge region 42 and through the connection 37 into the third chamber 38. The oil passes from there to the rotationally fixed connection or to the splined joint 21 between the two shafts 22 and 23, and therefore the rotationally fixed connection 21 is supplied to the desired extent with oil and lubricated.
[0070] If the gas turbine engine 1 is put into operation again at a later time, the rotational speed of the shafts 22 and 23 increases to values above the rotational speed threshold, and the first chamber 29 and the second chamber 30 are filled again with oil by the oil feed unit 26. If the dynamic oil level 32 in the two chambers 29 and 30 reaches the level shown in
[0071] However, if the gas turbine engine 1 is switched off, the third chamber 38 is acted upon with oil to the extent illustrated specifically in
[0072]
[0073] Furthermore,
[0074]
[0075] Oil is introduced from the first chamber 29 via the connecting bores 33, which are provided in the outer circumference 66 of the first part 28A of the oil divider 28, substantially radially outward into the second chamber 30. Over the operating period, the dynamic oil levels 32 arise in turn in the chambers 29 and 30, which are bounded by the inside diameter Di31 of the central opening 31 and correspond to each other and are shown below the axis of rotation 52 in
[0076] The dynamic oil level 32 in the second chamber 30 has the effect, in conjunction with rotational speeds of the shafts 32 and 23 above the rotation threshold, that the sealing element 36 is pressed to the previously described extent with its free inner edge region 42 in a sealing manner against a boundary wall 51 or partition of the oil divider 28. The partition 51 separates the second chamber 30 from the third chamber 38. The connection 37 which runs through the partition 51 between the second chamber 30 and the third chamber 38 is then blocked by the sealing element 36. This is in turn brought about by the hydraulic compressive force which acts on the sealing element 36 in the axial direction and results from the oil volume located in the second chamber 30 and the centrifugal force acting thereon above the rotational speed threshold. In addition, the second part 28B of the oil divider 28 comprises radial bores 60 via which oil is conducted out of the second chamber 30 in the direction of a further bearing unit 61.
[0077]
[0078]
[0079] The oil divider 28 is in turn divided and comprises the two parts 28A and 28B, between which the second chamber 30 is provided within the hollow-cylindrical region 27 of the shaft 22. The connecting bores 33 between the first chamber 29 and the second chamber 30 run in the axial direction through the first part 28A of the oil distributor 28. The oil feed unit 26 comprises introduction openings 53 which lead radially from the outside through the shaft 22 into the hollow-cylindrical region 27 of the shaft 22. Oil can be introduced through the shaft 22 into the first chamber 29 via the introduction openings 53.
[0080]
[0081]
[0082] If the gas turbine engine 1 transfers to the previously described extent during a switching-off operation into an operating state in which the static oil level 47 arises in the second chamber 30, the annular-disk-shaped region 41 of the sealing element 36 springs back in the manner illustrated in
[0083] The second part 28B of the oil divider 28 according to
LIST OF REFERENCE SIGNS
[0084] 1 Gas turbine engine [0085] 2 Bypass flow channel [0086] 3 Inlet region [0087] 4 Blower [0088] 5 Engine core [0089] 6 Compressor device [0090] 7 Separator [0091] 8 Turbine device [0092] 9 to 11 Rotor of the turbine device [0093] 12 Engine shaft [0094] 13 Auxiliary unit gearbox [0095] 14 Engine housing [0096] 15 Drive shaft [0097] 16 Auxiliary unit [0098] 17 Inner gearbox [0099] 18 Oil tank [0100] 19 Component [0101] 20 Apparatus [0102] 21 Rotationally fixed connection [0103] 22 Shaft [0104] 23 Shaft [0105] 24 Interior of the auxiliary unit gearbox 13 [0106] 25 Environment of the auxiliary unit gearbox 13 [0107] 26 Oil feed unit [0108] 27 Hollow-cylindrical region of the shaft 22 [0109] 28 Oil distributor [0110] 28A, 28B Parts of the oil distributor [0111] 29 First chamber [0112] 30 Second chamber [0113] 31 Central opening of the oil distributor [0114] 32 Dynamic oil level [0115] 33 Connecting bores between the first chamber and the second chamber [0116] 34 Ring region [0117] 35 Bearing unit [0118] 36 Sealing element [0119] 37 Connection between the first chamber and the third chamber [0120] 38 Third chamber [0121] 38A Oil volume in the third chamber 28 [0122] 39 Axial stop [0123] 40 Stop surface of the stop 39 [0124] 41 Annular disk region of the sealing element [0125] 42 Free inner edge region of the annular disk region [0126] 43 End face of the shaft 23 [0127] 44 Shaft end of the shaft 23 [0128] 45 Sealing bead or sealing lip of the sealing element [0129] 46, 47 Static oil level [0130] 48 Central venting bore of the second chamber [0131] 49 Further seal [0132] 50 Inner groove of the oil distributor [0133] 51 Boundary wall [0134] 52 Axis of rotation [0135] 53 Introduction opening [0136] 54 Radial outer region of the sealing element 36 [0137] 55 Inner side of the shaft 22 [0138] 56 Axial region of the sealing element 36 [0139] 57 Further axial region of the sealing element [0140] 58 Discharge bores of the second part 28B of the oil distributor 28 [0141] 60 Radial bore [0142] 61 Further bearing unit [0143] 65 Overlapping region [0144] 66 Outer circumference of the oil distributor [0145] 67 Flat sealing disk region [0146] 68 Radial outer region of the sealing element [0147] 70 Radial wall region [0148] A Core flow [0149] B Bypass flow [0150] Di31 Inside diameter of the central opening 31 [0151] Di39 Inside diameter of the axial stop 39 [0152] Di41 Inside diameter of the annular disk region 41