Elastic foil gas bearing and transmission device

Abstract

The invention belongs to the technical field of mechanical transmission, and discloses an elastic foil gas bearing which comprises an elastic foil gas bearing body, a first bearing ring and a second bearing ring. The elastic foil gas bearing body is fixedly sleeved with the first bearing ring, the first bearing ring is sleeved with the second bearing ring, and the first bearing ring and the second bearing ring rotate relatively; a first vent hole is formed in the first bearing ring, a second vent hole is formed in the second bearing ring, a gap is formed in the elastic foil gas bearing body in the circumferential direction, and the first vent hole corresponds to the gap in position; the first vent hole and the second vent hole comprise at least two states through relative rotation of the two bearing rings: in the first state, the projection parts of the first vent hole and the second vent hole on the contact surface of the two bearing rings coincide; and in the second state, the projections of the first vent hole and the second vent hole on the contact surface of the two bearing rings do not coincide. The flow velocity of airflow on the surface of the rotor can be reduced, and turbulent flow is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of mechanical transmission. More specifically, the present invention relates to an elastic foil gas bearing and a transmission device. Background Art

[0002] A bearing is a component that plays a role in fixing and reducing the load friction coefficient during the mechanical transmission process. Its main function is to support the mechanical rotating body to reduce the mechanical load friction coefficient of the equipment during the transmission process. In recent years, with the increasingly wide application of high-speed rotating machinery in fields such as aerospace and energy equipment, the working environment has become increasingly harsh, and the requirements for lubrication and support have gradually increased. In an oil-free lubrication system, compared with complex and expensive support methods such as electromagnetic bearings, the elastic foil gas bearing has the advantages of high rotational speed, good adaptability, no wear, low cost, high reliability, high temperature resistance, etc. It does not require additional oil supply and other auxiliary devices, and has a simple structure, which is one of the key technologies for oil-free lubrication.

[0003] Traditional air foil bearings rely on the high-speed rotating rotor to apply pressure to the gas, and use the wedge effect to generate dynamic pressure to carry the load. This bearing uses an elastic foil as its structure, which not only has a certain rigidity but also provides a shock absorption effect, enabling the bearing to withstand a certain load. However, due to the cross-coupling effect of gas dynamic pressure, the stability of this bearing-rotor system is not ideal. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention innovatively provides an elastic foil gas bearing and a transmission device, which can spray high-pressure air with a certain flow rate and pressure on the surface of the journal, so as to reduce the air flow velocity on the surface of the rotor, reduce turbulence, and thus improve the stability of the bearing-rotor system.

[0005] To achieve the above technical objectives, the first aspect of the present invention discloses an elastic foil gas bearing body for sleeving on a supporting journal, including an elastic foil gas bearing body, a first bearing ring and a second bearing ring;

[0006] The first bearing ring is sleeved on the outside of the elastic foil gas bearing body, the elastic foil gas bearing body is fixedly connected with the first bearing ring, the second bearing ring is sleeved on the outside of the first bearing ring, and at least one of the second bearing ring and the first bearing ring rotates around the axis of the first bearing ring to realize the relative rotation between the two;

[0007] The first bearing ring is provided with a first ventilation hole, the second bearing ring is provided with a second ventilation hole, and a gap is arranged along the circumferential direction on the elastic foil gas bearing body, and the first ventilation hole corresponds to the position of the gap;

[0008] The relative rotation of the first vent hole and the second vent hole through the second bearing ring and the first bearing ring includes at least the following two states:

[0009] First state, the projections of the first vent hole and the second vent hole on the contact surface of the first bearing ring and the second bearing ring partially overlap;

[0010] Second state, the projections of the first vent hole and the second vent hole on the contact surface of the first bearing ring and the second bearing ring do not overlap at all;

[0011] When the first vent hole and the second vent hole are in the first state, air flow is introduced from the second vent hole into the first vent hole and blown onto the matching journal.

[0012] Furthermore, the elastic foil gas bearing body includes a bottom arch foil and a top foil;

[0013] The top foil is arc-shaped, and a plurality of the top foils are evenly distributed along the circumference of the journal and attached to the journal, and there is a gap between adjacent top foils;

[0014] A bottom arch foil is fixedly provided corresponding to the outside of each top foil.

[0015] Furthermore, it further includes a third bearing ring sleeved outside the second bearing ring, and at least one of the third bearing ring and the second bearing ring rotates around the axis of the second bearing ring to achieve relative rotation between the two, and a third vent hole is provided on the third bearing ring;

[0016] The relative rotation of the first vent hole, the second vent hole and the third vent hole through the relative rotation of the second bearing ring and the first bearing ring and the relative rotation of the third bearing ring and the second bearing ring includes at least the following two states:

[0017] First state, the projections of the first vent hole and the second vent hole on the contact surface of the first bearing ring and the second bearing ring partially overlap, and the projections of the second vent hole and the third vent hole on the contact surface of the second bearing ring and the third bearing ring partially overlap;

[0018] Second state, at least one of the projections of the first vent hole and the second vent hole on the contact surface of the first bearing ring and the second bearing ring and the projections of the second vent hole and the third vent hole on the contact surface of the second bearing ring and the third bearing ring does not overlap at all.

[0019] Furthermore, the aperture area of the second vent hole is larger than the aperture areas of the first vent hole and the third vent hole.

[0020] Further, a fourth ventilation hole is formed in the second bearing ring, and the aperture area of the fourth ventilation hole is larger than the aperture areas of the first ventilation hole and the third ventilation hole.

[0021] Further, a plurality of the first ventilation holes are arranged along the circumferential direction and / or the axial direction of the first bearing ring, a plurality of the second ventilation holes are arranged along the circumferential direction and / or the axial direction of the second bearing ring, and a plurality of the third ventilation holes are arranged along the circumferential direction and / or the axial direction of the third bearing ring.

[0022] Further, a driving device is further included, and the driving device is used for driving the first bearing ring and the second bearing ring to rotate relatively and the second bearing ring and the third bearing ring to rotate relatively.

[0023] Further, the driving device includes a driving gear, an external tooth ring and an internal tooth ring. The driving gear is fixed on the end face of the second bearing ring, the driving gear is rotatably connected with the second bearing ring, the external tooth ring is fixed on the end face of the first bearing ring, the internal tooth ring is fixed on the end face of the third bearing ring, the driving gear is respectively meshed with the external tooth ring and the internal tooth ring, the driving gear is driven by a driving source to rotate, and the driving gear drives the external tooth ring and the internal tooth ring to rotate in different directions.

[0024] Further, the cross-sectional shapes of the first ventilation hole and the second ventilation hole are rectangular or oblong.

[0025] To achieve the above technical object, a second aspect of the present invention discloses a transmission device, including the flexible foil gas bearing described in the first aspect above.

[0026] The beneficial effects of the present invention are as follows:

[0027] The present invention adjusts the alignment state of the first ventilation hole and the second ventilation hole through the relatively rotatable first bearing ring and second bearing ring. When the bearing works at an ultra-high speed, high-pressure air with a certain flow rate and pressure is sprayed from the first ventilation hole to the journal, so that the air flow velocity on the surface of the rotor is reduced, disrupting the original turbulent flow state, and effectively increasing the stability of the system. Description of the Drawings

[0028] Figure 1 is a schematic structural view of the flexible foil gas bearing according to an embodiment of the present invention.

[0029] Figure 2 is a right view of the structure of the flexible foil gas bearing according to an embodiment of the present invention.

[0030] Figure 3It is a sectional view of the elastic foil gas bearing in the A'-A' direction when the first vent hole and the second vent hole are in the first state.

[0031] Figure 4 It is a sectional view of the elastic foil gas bearing in the A'-A' direction when the first vent hole and the second vent hole are in the second state.

[0032] Figure 5 It is a schematic structural diagram of the elastic foil gas bearing according to another embodiment of the present invention.

[0033] Figure 6 It is a schematic perspective view of the other side of the elastic foil gas bearing according to another embodiment of the present invention.

[0034] Figure 7 It is a right view of the structure of the elastic foil gas bearing according to another embodiment of the present invention.

[0035] Figure 8 It is a sectional view of the elastic foil gas bearing in the A-A direction when the first vent hole, the second vent hole and the third vent hole are in the first state.

[0036] Figure 9 It is a sectional view of the elastic foil gas bearing in the A-A direction when the first vent hole, the second vent hole and the third vent hole are in the second state.

[0037] Figure 10 It is a sectional view of the elastic foil gas bearing in the A-A direction according to still another embodiment of the present invention.

[0038] Figure 11 It is a sectional view of the elastic foil gas bearing in the A-A direction according to yet another embodiment of the present invention.

[0039] Figure 12 It is a sectional view of the elastic foil gas bearing in the B-B direction according to another embodiment of the present invention.

[0040] Figure 13 It is a rear view of the elastic foil gas bearing according to another embodiment of the present invention.

[0041] Figure 14 It is a sectional view of the elastic foil gas bearing in the C-C direction according to another embodiment of the present invention.

[0042] In the figure,

[0043] 1. First bearing ring; 11. First ventilation hole; 12. First protrusion; 2. Second bearing ring; 21. Second ventilation hole; 22. Fourth ventilation hole; 23. Second protrusion; 24. Second chute; 25. Second notch; 3. Third bearing ring; 31. Third ventilation hole; 32. Third chute; 33. Third notch; 4. Elastic foil gas bearing body; 41. Top foil; 42. Bottom arch foil; 5. Driving device; 51. Driving gear; 52. Outer tooth ring; 53. Inner tooth ring; 6. Driving shaft; 7. Journal. Detailed implementation mode

[0044] The elastic foil gas bearing and transmission device provided by the present invention will be explained and described in detail below with reference to the accompanying drawings of the specification.

[0045] This embodiment specifically discloses an elastic foil gas bearing for sleeving on a supporting journal 7, such as Figure 1-4 shown. The elastic foil gas bearing includes an elastic foil gas bearing body 4, a first bearing ring 1 and a second bearing ring 2. The elastic foil gas bearing body 4 is sleeved on the journal 7. The first bearing ring 1 is sleeved on the outside of the elastic foil gas bearing body 4, and the elastic foil gas bearing body 4 is fixedly connected to the first bearing ring 1. The second bearing ring 2 is sleeved on the outside of the first bearing ring 1. The first bearing ring 1 and the second bearing ring 2 are coaxially sleeved, and at least one of the second bearing ring 2 and the first bearing ring 1 rotates around the axis of the first bearing ring 1 to realize the relative rotation between the two, that is, the first bearing ring 1 can remain stationary and the second bearing ring 2 rotates around the first bearing ring 1; or the second bearing ring 2 can remain stationary and the first bearing ring 1 rotates around its own axis; or the first bearing ring 1 and the second bearing ring 2 can rotate in opposite directions.

[0046] As Figure 1 , 3 and 4 shown, the elastic foil gas bearing body 4 includes a bottom arch foil 42 and a top foil 41. The top foil 41 is arc-shaped, and a plurality of top foils 41 are evenly distributed along the circumference of the journal 7 and are attached to the journal 7. There is a gap between adjacent top foils 41, that is, a distance is maintained between adjacent top foils to form a gap; a bottom arch foil 42 is fixedly corresponding to the outside of each top foil 41, and the bottom arch foil 42 is fixedly connected to the top foil 41. The two ends of the bottom arch foil 42 do not exceed the two ends of the top foil 41. In this embodiment, the bottom arch foil 42 is fixed on the inner ring of the first bearing ring 1, and then the top foil 41 is fixed on the inner side of the bottom arch foil 42. The fixing method can be welding or riveting.

[0047] In this embodiment, the inner side refers to the side close to the central axis of the elastic foil gas bearing, and the outer side refers to the side far from the central axis of the elastic foil gas bearing.

[0048] As Figure 1-4As shown in the figure, a first vent hole 11 is provided on the first bearing ring 1. The aperture diameter of the first vent hole 11 can be along the radial direction of the first bearing ring 1. The first vent hole 11 penetrates through the first bearing ring 1, that is, the first vent hole 11 extends from the inner ring to the outer ring of the first bearing ring 1; a second vent hole 21 is provided on the second bearing ring 2. The aperture diameter of the second vent hole 21 can be along the radial direction of the second bearing ring 2. The second vent hole 21 penetrates through the second bearing ring 2, that is, the second vent hole 21 extends from the inner ring to the outer ring of the second bearing ring 2; the position of the first vent hole 11 corresponds to the gap of the flexible foil gas bearing body 4, and is used to make the air flow entering through the first vent hole 11 blow towards the journal 7 through the gap.

[0049] Since the first vent hole 11 corresponds to the gap position, it is preferably set that the number of the first vent holes 11 along the circumferential direction is multiple, corresponding to the gaps one by one. There are multiple gaps along the circumferential direction of the flexible foil gas bearing body 4. Therefore, there are multiple first vent holes 11 with the same number as the gaps on each circumferential direction of the first bearing ring 1. In order to increase the air intake, multiple circles can be set. That is, multiple first vent holes 11 are also provided along the axial direction of the first bearing ring 1, that is, multiple first vent holes 11 are correspondingly provided along the length direction of the axial direction of the flexible foil gas bearing body 4 for each gap. Multiple second vent holes 21 can also be provided on the second bearing ring 2 in both the circumferential direction and / or the axial direction. The number and position of the second bearing rings 2 can be the same as and correspond one by one to those of the first bearing ring 1, or can be different.

[0050] As Figure 1 、 3 As shown in FIGS. 4, there are 4 first vent holes 11 provided along the circumferential direction of the first bearing ring and 3 first vent holes 11 provided along the axial direction of the first bearing ring, and there are 4 second vent holes 21 provided along the circumferential direction of the second bearing ring and 3 second vent holes 21 provided along the axial direction of the second bearing ring.

[0051] The relative rotation of the first vent hole 11 and the second vent hole 21 through the second bearing ring 2 and the first bearing ring 1 includes at least the following two states:

[0052] The first state is that the projections of the first vent hole 11 and the second vent hole 21 on the contact surface of the first bearing ring 1 and the second bearing ring 2 partially overlap, that is, Figure 3 In the shown state, the first vent hole 11 and the second vent hole 21 have a certain overlap on the contact surface of the first bearing ring 1 and the second bearing ring 2, but do not completely overlap. The first vent hole 11 is partially blocked by the second bearing ring 2, and the second vent hole 21 is partially blocked by the first bearing ring 1. At this time, high-pressure gas is injected from the second vent hole 21 on the outermost second bearing ring 2. The air flow blows obliquely towards the journal 7 through the second vent hole 21 and the first vent hole 11, spraying high-pressure air with a certain flow rate and pressure on the surface of the journal 7, so that the air flow velocity on the surface of the rotor is reduced, the turbulence is reduced, and thus the stability of the bearing-rotor system is improved.

[0053] In the second state, the projections of the first vent hole 11 and the second vent hole 21 on the contact surface of the first bearing ring 1 and the second bearing ring 2 do not overlap at all, that is Figure 4 in the state shown, there is no airflow blowing towards the journal 7.

[0054] When the first vent hole 11 and the second vent hole 21 are in the first state, as Figure 3 shown, the airflow is introduced from the second vent hole 21 into the first vent hole 11 and blown onto the matching journal 7, thereby reducing the gas flow rate on the rotor surface, reducing turbulence, and improving the stability of the bearing-rotor system.

[0055] The relative rotation of the first bearing ring and the second bearing ring in this embodiment can be achieved by a driving device. For example, a driving gear is provided on the end face of one of the first bearing ring and the second bearing ring. The driving gear is rotatably connected to the bearing ring where it is located. A gear ring meshing with the driving gear is fixed on the end face of the other of the first bearing ring and the second bearing ring. The gear ring is coaxially fixed with the bearing ring where it is located. The driving source drives the driving gear to rotate, and then drives the gear ring to rotate, realizing the rotation of the bearing ring where the gear ring is located.

[0056] In some embodiments, as Figure 5-9 shown, the compliant foil gas bearing of the present application further includes a third bearing ring 3. The third bearing ring 3 is sleeved outside the second bearing ring 2. At least one of the third bearing ring 3 and the second bearing ring 2 rotates around the axis of the second bearing ring 2 to realize their relative rotation, that is, one of the second bearing ring 2 and the third bearing ring 3 remains stationary and the other rotates, or the second bearing ring 2 and the third bearing ring 3 rotate in opposite directions; a third vent hole 31 is provided on the third bearing ring 3. The aperture of the third vent hole 31 is arranged along the radial direction of the third bearing ring 3. The third vent hole 31 penetrates the third bearing ring 3 and extends from the inner ring to the outer ring of the third bearing ring 3.

[0057] The first vent hole 11, the second vent hole 21, and the third vent hole 31 include at least the following two states through the relative rotation of the second bearing ring 2 and the first bearing ring 1 and the relative rotation of the third bearing ring 3 and the second bearing ring 2:

[0058] In the first state, the projections of the first vent hole 11 and the second vent hole 21 on the contact surface of the first bearing ring 1 and the second bearing ring 2 partially overlap, and the projections of the second vent hole 21 and the third vent hole 31 on the contact surface of the second bearing ring 2 and the third bearing ring 3 partially overlap, as Figure 8In the shown state, high-pressure gas is injected from the third vent hole 31 on the outermost third bearing ring 3, and successively passes through the third vent hole, the second vent hole, and the first vent hole to obliquely blow towards the journal. The airflow has a certain flow rate and pressure, which reduces the airflow velocity on the rotor surface and reduces turbulence, thereby improving the stability of the bearing-rotor system; adding a third bearing ring on the outside of the second bearing ring makes it easier to adjust the oblique angle and flow rate of the airflow, improves efficiency, and further improves the stability of the bearing-rotor system.

[0059] In the second state, at least one of the projections of the first vent hole 11 and the second vent hole 12 on the contact surface of the first bearing ring 1 and the second bearing ring 2, and the projections of the second vent hole 21 and the third vent hole 31 on the contact surface of the second bearing ring 2 and the third bearing ring 3 do not overlap at all, that is, an air flow path cannot be formed, and the airflow does not need to blow towards the journal. Figure 9 The shown state is that all the projections do not overlap at all.

[0060] A plurality of first vent holes 11 are arranged along the circumferential and / or axial directions of the first bearing ring 1, a plurality of second vent holes 21 are arranged along the circumferential and / or axial directions of the second bearing ring 2, and a plurality of third vent holes 31 are arranged along the circumferential and / or axial directions of the third bearing ring 3. The number and positions of the first vent hole, the second vent hole, and the third vent hole can be the same and in one-to-one correspondence, or different. When the number and positions of the first vent hole, the second vent hole, and the third vent hole are the same and in one-to-one correspondence, when in the first state, the airflow blowing towards the journal is symmetrical.

[0061] When the first vent hole 11 and the second vent hole 21 are in a completely deviated state, the airflow cannot be introduced from the second vent hole 21 into the first vent hole 11. Similarly, when the second vent hole 21 and the third vent hole 31 are in a completely deviated state, the airflow cannot be introduced from the third vent hole 31 into the second vent hole 21. At this time, the airflow cannot be introduced from the outside into the bearing.

[0062] When only the first bearing ring and the second bearing ring are sleeved outside the elastic foil gas bearing body 4, when the first vent hole 11 and the second vent hole 21 are in the first state of partial deviation, the airflow can enter the first vent hole 11 from the second vent hole 21. Due to partial occlusion between the first vent hole 11 and the second vent hole 21, the high-pressure airflow as a whole will shoot out from the first vent hole 11 at an angle to the radial direction. And the first vent hole 11 is aligned with the gap of the elastic foil gas bearing body 4. After the high-pressure airflow shoots out from the first vent hole 11, it can reduce the airflow velocity on the rotor surface, disrupt the airflow originally in a turbulent state, and effectively increase the stability of the bearing system, especially when the shooting direction is opposite to the bearing rotation direction, the effect is particularly obvious.

[0063] Similarly, when a third bearing ring is sleeved outside the second bearing ring, when the first vent hole 11, the second vent hole 21, and the third vent hole 31 are in the first state, air flow can enter the second vent hole 21 from the third vent hole 31. Due to partial occlusion between the third vent hole 31 and the second vent hole 21, and partial occlusion between the second vent hole 21 and the first vent hole 11, the overall high-pressure air flow will form an angle with the radial direction and shoot out from the first vent hole 11, which can reduce the air flow velocity on the surface of the rotor, disrupt the original turbulent flow state, and effectively increase the stability of the system. Especially when the shooting direction is opposite to the rotation direction of the bearing, the effect is particularly obvious.

[0064] In this embodiment, the cross-sectional shapes of the first vent hole 11, the second vent hole 21, and the third vent hole 31 are rectangular or oblong, with their length directions along the circumferential direction of the bearing ring and their width directions along the axial direction of the bearing ring.

[0065] As Figure 3 、 4 、8 and 9 show, the aperture areas of all the vent holes can be the same. However, in order to increase the adjustment angle range and the flow rate, as Figure 10 shows, the aperture area of the second vent hole 21 can be set to be larger than the aperture areas of the first vent hole 11 and the third vent hole 31. Preferably, the length of the second vent hole 21 is greater than the lengths of the first vent hole 11 and the third vent hole 31, and the widths of the second vent hole 21, the first vent hole 11, and the third vent hole 31 are the same.

[0066] Optionally, as Figure 11 shows, a fourth vent hole 22 is provided on the second bearing ring 2, and the aperture area of the fourth vent hole 22 is larger than the aperture areas of the first vent hole 11 and the third vent hole 31. A plurality of fourth vent holes are provided along the circumferential direction and / or the axial direction of the second bearing ring.

[0067] As Figure 12 and 14 show, in order to prevent axial misalignment between the first bearing ring 1 and the second bearing ring 2, an axial limiting device is provided between the first bearing ring 1 and the second bearing ring 2. The axial limiting device includes a first protrusion 12 provided on the outer ring of the first bearing ring 1, a second sliding groove 24 provided on the inner ring of the second bearing ring 2, and a second notch 25 provided on the end face of the second bearing ring 2 near the inner ring. The second sliding groove 24 is an annular groove, and the central axis of the second sliding groove 24 coincides with the central axis of the second bearing ring 2. Figure 12The position of the middle section is the position where the second sliding groove 24 is located. The second notch 25 extends from the end face of the second bearing ring 2 to the second sliding groove 24 and communicates with the second sliding groove 24. The first protrusion 12 provided on the first bearing ring 1 is snapped into the second notch 25, then enters the second sliding groove 24 and rotates along the second sliding groove 24 in the second sliding groove 24 without axial displacement.

[0068] Similarly, in order to prevent axial misalignment between the second bearing ring 2 and the third bearing ring 3, an axial limiting device is provided between the second bearing ring 2 and the third bearing ring 3. The axial limiting device includes a second protrusion 23 provided on the outer ring of the second bearing ring, a third sliding groove 32 provided on the inner ring of the third bearing ring 3, and a third notch 33 provided on the end face of the third bearing ring 3 near the inner ring. The third sliding groove 32 is an annular groove, and the central axis of the third sliding groove coincides with the central axis of the third bearing ring 3. The third notch extends from the end face of the third bearing ring to the third sliding groove and communicates with the third sliding groove. The second protrusion 23 provided on the second bearing ring is snapped into the third notch 33, then enters the third sliding groove and rotates along the third sliding groove in the third sliding groove without axial displacement.

[0069] In addition, in order to control whether to eject gas, a driving device 5 can be provided. The driving device 5 is used to drive the relative rotation of the first bearing ring 1 and the second bearing ring 2 and the relative rotation of the second bearing ring 2 and the third bearing ring 3, so as to control the first ventilation hole 11, the second ventilation hole 21, and the third ventilation hole 31 to be in the first state or the second state. When the first ventilation hole 11, the second ventilation hole 21, and the third ventilation hole 31 are in the first state, when the second bearing ring 2 rotates relative to the first bearing ring 1 and the third bearing ring 3 rotates relative to the second bearing ring 2, the circumferential spacing between the first ventilation hole 11 and the third ventilation hole 31 will be further enlarged, thereby changing the angle of gas ejection, and thus the ejection airflow can be adjusted more flexibly.

[0070] Specifically, the driving device 5 includes a driving gear 51, an external gear ring 52, and an internal gear ring 53. The driving gear 51 is fixed on the end face of the second bearing ring 2, and the driving gear 51 is rotationally connected to the second bearing ring 2. The external gear ring 52 is fixed on the end face of the first bearing ring 1, and the external gear ring 52 is coaxially fixed with the first bearing ring 1. The internal gear ring 53 is fixed on the end face of the third bearing ring 3, and the internal gear ring 53 is coaxially fixed with the third bearing ring 3. The driving gear 51 is respectively meshed with the external gear ring 52 and the internal gear ring 53. The driving gear 51 is driven by a driving source to rotate, and the driving gear 51 drives the external gear ring 52 and the internal gear ring 53 to rotate in different directions. A through hole is provided in the driving gear 5, and a driving shaft 6 is inserted into the through hole. The driving shaft 6 and the driving gear 5 are connected by a keyway. When the driving source drives the driving shaft 6 to rotate, the driving gear 5 can be driven to rotate. The driving source can be a micro motor, and the driving source can be provided inside or outside the second bearing ring 2.

[0071] Working principle of the compliant foil gas bearing according to the embodiments of the present application:

[0072] When the bearing is working, with the rotation of the journal 7, a dynamic pressure with a gradient is formed in the wedge-shaped space between the journal 7 and the top foil 41, causing the journal 7 to completely separate from the contact with the top foil 41, forming a stable lubricating gas film and reaching the gas film suspension working state.

[0073] When gas injection adjustment is required, the second bearing ring 2 rotates relative to the first bearing ring 1. When the second vent hole 21 and the first vent hole 11 partially overlap in the first state, the air flow is introduced from the second vent hole 21 into the first vent hole 11, forming an oblique air flow, which can reduce the air flow velocity on the surface of the rotor, disrupt the originally turbulent air flow, and effectively increase the stability of the bearing system. Especially when the ejection direction is opposite to the rotation direction of the bearing, the effect is particularly obvious.

[0074] Similarly, when the third bearing ring 3 rotates relative to the second bearing ring 2, the overlapping area of the third vent hole 31 and the second vent hole 21 can also be adjusted to adjust the angle and flow rate of the air flow entering.

[0075] In addition, when the first vent hole 11 and the second vent hole 21 partially overlap in the first state, by adjusting the relative rotation angle of the second bearing ring 2 relative to the first bearing ring 1, the angle and flow rate of the air flow ejected from the first vent hole 11 can be adjusted.

[0076] The compliant foil gas bearing of the present application has the following advantages:

[0077] 1. In the present invention, by the first bearing ring and the second bearing ring that can rotate relative to each other, and the first vent hole and the second vent hole provided thereon, the alignment state of the first vent hole and the second vent hole is adjusted. When the bearing operates at an ultra-high speed state, high-pressure air with a certain flow rate and pressure is ejected from the first vent hole, reducing the air flow velocity on the surface of the rotor, disrupting the originally turbulent flow, and effectively increasing the stability of the system.

[0078] 2. When the first bearing ring and the second bearing ring rotate relative to each other and the second bearing ring and the third bearing ring rotate relative to each other in the present invention, the direction and magnitude of the air flow ejected from the first vent hole can be adjusted.

[0079] 3. In the present invention, by setting the aperture cross-sectional area of the second vent hole of the second bearing ring to be larger than that of the first vent hole and the third vent hole, or additionally setting the aperture cross-sectional area of the fourth vent hole to be larger than that of the first vent hole and the third vent hole, the adjustment range of the angle and flow rate of the ejected air flow can be effectively improved.

[0080] This embodiment also discloses a transmission device, which includes the elastic foil gas bearing described in the above embodiment. This transmission device can be applied in the fields of aerospace, energy equipment, etc.

[0081] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0082] In the present invention, unless otherwise clearly defined and limited, the terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. It can be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0083] In the description of this specification, the description with reference to terms such as "this embodiment", "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any at least one embodiment or example. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0084] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0085] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent substitutions, and simple improvements made to the substantial content of the present invention shall be included within the protection scope of the present invention.

Claims

1. An elastic foil gas bearing, used for sleeve installation on a matching shaft journal (7), comprising an elastic foil gas bearing body (4), characterized in that: Also includes a first bearing ring (1) and a second bearing ring (2); The first bearing ring (1) is sleeved on the outer side of the elastic foil gas bearing body (4), the elastic foil gas bearing body (4) is fixedly connected to the first bearing ring (1), the second bearing ring (2) is sleeved on the outer side of the first bearing ring (1), and at least one of the second bearing ring (2) and the first bearing ring (1) rotates around the axis of the first bearing ring (1) to achieve relative rotation between the two; The first bearing ring (1) is provided with a first vent hole (11), the second bearing ring (2) is provided with a second vent hole (21), a gap is provided on the elastic foil gas bearing body (4) along the circumferential direction, and the first vent hole (11) corresponds to the position of the gap; The first vent hole (11) and the second vent hole (21) include at least the following two states through the relative rotation of the second bearing ring (2) and the first bearing ring (1): In a first state, the projections of the first vent hole (11) and the second vent hole (21) on the contact surface of the first bearing ring (1) and the second bearing ring (2) partially overlap; In the second state, projections of the first vent hole (11) and the second vent hole (21) on the contact surface of the first bearing ring (1) and the second bearing ring (2) do not overlap at all; When the first vent hole (11) and the second vent hole (21) are in a first state, air flow is introduced from the second vent hole (21) into the first vent hole (11) and blown onto the matching shaft neck (7).

2. The elastic foil gas bearing according to claim 1, characterized in that: The elastic foil gas bearing body (4) comprises a bottom foil (42) and a top foil (41); The top foil (41) is in an arc shape, and a plurality of the top foils (41) are evenly distributed along the circumference of the shaft neck (7) and are attached to the shaft neck (7), and there is a gap between adjacent top foils (41); The bottom arch foil (42) is correspondingly fixed to the outer side of each top foil (41).

3. The elastic foil gas bearing according to claim 1, characterized in that: It also comprises a third bearing ring (3), the third bearing ring (3) being sleeved on the outer side of the second bearing ring (2), at least one of the third bearing ring (3) and the second bearing ring (2) being rotated around the axis of the second bearing ring (2) to achieve relative rotation of the two, and the third bearing ring (3) being provided with a third vent hole (31); The first vent hole (11), the second vent hole (21) and the third vent hole (31) include at least the following two states through the relative rotation of the second bearing ring (2) and the first bearing ring (1) and the relative rotation of the third bearing ring (3) and the second bearing ring (2): In a first state, the projections of the first vent hole (11) and the second vent hole (21) on the contact surface of the first bearing ring (1) and the second bearing ring (2) overlap, and the projections of the second vent hole (21) and the third vent hole (31) on the contact surface of the second bearing ring (2) and the third bearing ring (3) overlap; In the second state, at least one of the projections of the first ventilation hole (11) and the second ventilation hole (12) on the contact surface of the first bearing ring (1) and the second bearing ring (2), and the projections of the second ventilation hole (21) and the third ventilation hole (31) on the contact surface of the second bearing ring (2) and the third bearing ring (3) do not overlap.

4. The elastic foil gas bearing according to claim 3, characterized in that: The aperture area of ​​the second ventilation hole (21) is larger than the aperture areas of the first ventilation hole (11) and the third ventilation hole (31).

5. The elastic foil gas bearing according to claim 3, characterized in that: The second bearing ring (2) is provided with a fourth ventilation hole (22), and the aperture area of ​​the fourth ventilation hole (22) is larger than the aperture areas of the first ventilation hole (11) and the third ventilation hole (31).

6. The elastic foil gas bearing according to claim 3, characterized in that: A plurality of the first ventilation holes (11) are arranged along the circumference and / or axial direction of the first bearing ring (1), a plurality of the second ventilation holes (21) are arranged along the circumference and / or axial direction of the second bearing ring (2), and a plurality of the third ventilation holes (31) are arranged along the circumference and / or axial direction of the third bearing ring (3).

7. The elastic foil gas bearing according to claim 3, characterized in that: It also comprises a driving device (5), wherein the driving device (5) is used to drive the first bearing ring (1) and the second bearing ring (2) to rotate relative to each other, and the second bearing ring (2) and the third bearing ring (3) to rotate relative to each other.

8. The elastic foil gas bearing according to claim 7, characterized in that: The driving device (5) comprises a driving gear (51), an outer gear ring (52) and an inner gear ring (53); the driving gear (51) is fixed on the end face of the second bearing ring (2); the driving gear (51) is rotatably connected to the second bearing ring (2); the outer gear ring (52) is fixed on the end face of the first bearing ring (1); the inner gear ring (53) is fixed on the end face of the third bearing ring (3); the driving gear (51) is meshed with the outer gear ring (52) and the inner gear ring (53) respectively; the driving gear (51) is driven to rotate by a driving source; the driving gear (51) drives the outer gear ring (52) and the inner gear ring (53) to rotate in different directions.

9. The elastic foil gas bearing according to any one of claims 1 to 8, characterized in that: The cross-sectional shape of the first ventilation hole (11) and the second ventilation hole (21) is rectangular or oblong.

10. A transmission device, characterized in that: The invention comprises the elastic foil gas bearing as described in any one of claims 1 to 9.

Images