CN116696933A - Gas dynamic pressure bearing with tiltable foil - Google Patents

Abstract

The application relates to the technical field of gas bearings, and provides a gas dynamic pressure bearing with a tiltable foil, which comprises: bearing sleeve, foil, auxiliary support foil and top foil; the foil is formed by connecting a plurality of upper and lower triangle structures connected in the middle and pressed by a metal plate in parallel, wherein the upper triangle structure is reversely connected with the lower triangle structure, a certain gap is reserved between two middle beams connected with the upper and lower triangle structures, an auxiliary supporting foil is arranged between the two middle beams, the two middle beams are inwards bent and deformed to press the auxiliary supporting foil after the foil structure bears load, certain friction damping is generated, the upper triangle structure rotates leftwards or rightwards according to the load direction, the lower triangle structure is deformed to two sides and transmits the load to the adjacent upper and lower triangle structures, the upper surface of the foil is contacted with the top foil surface, and the lower surface of the foil is contacted with the inner surface of the bearing sleeve; the auxiliary supporting foil support is inserted into a chute in the bearing sleeve; the bearing sleeve supports a foil, and the foil supports a top foil; one end of the foil sheet and one end of the arc-shaped top foil sheet are free, and the other end of the foil sheet and the arc-shaped top foil sheet are fixed on the bearing sleeve together. Compared with the traditional gas foil bearing, the foil rotatable characteristic is beneficial to adjusting the local deformation of the top foil and improving the running stability of the gas foil bearing.

Description

Gas dynamic pressure bearing with tiltable foil

Technical Field

The application relates to the technical field of radial gas dynamic pressure bearings, in particular to a gas dynamic pressure bearing with a tiltable foil.

Background

The gas dynamic pressure bearing utilizes the gas dynamic pressure effect to generate a high-pressure air film, and the non-contact lubrication support rotor has the advantages of oil-free lubrication, high efficiency output and the like, and is more widely applied to high-speed light-load rotating equipment such as high-speed air circulators, oil-free turbochargers, fuel cell air compressors and the like compared with an oil lubrication bearing.

However, the dynamic pressure gas film enclosed by the high-speed rotor and the static top foil has a very large speed gradient along the thickness direction of the gas film, so that the gas film causes excitation which generates about 0.5 times of the speed of rotation, the excitation acts on the rotor, when the excitation frequency is close to the system frequency, subsynchronous resonance of the rotor is caused, the stability of the system is seriously affected, and the dynamic pressure bearing supporting rotor system cannot develop towards the direction of higher speed. In order to eliminate the influence of subsynchronous excitation on a rotor system, the integrated tilting pad pneumatic dynamic pressure bearing is a good method, a multi-petal pad is structurally arranged, and the tilting characteristic around a pivot point cuts off the continuity of a gas film, but the metal structure pad of the bearing has small damping and small bearing capacity, so that the application range is limited.

Disclosure of Invention

Aiming at the technical defects, the application provides the gas dynamic pressure bearing with the tiltable foil, which keeps the advantage of large bearing capacity of the foil bearing, has the characteristic of rotating along the load direction after the foil structure is deformed, and solves the technical problem of poor stability of the existing gas dynamic pressure bearing system. The technical effects which can be produced by the preferred technical scheme among the technical schemes provided by the application are described below.

In order to achieve the technical purpose, the application provides the following technical scheme:

the application provides a foil tiltable gas dynamic pressure bearing, comprising: bearing housing, foil, auxiliary stay foil and top foil.

In one embodiment, the foil is formed by connecting a plurality of upper triangular structures and lower triangular structures which are connected in the middle and are pressed by metal plates in parallel, the foil can be of a whole structure or a single structure, wherein the upper triangular structure is reversely connected with the lower triangular structure, a certain gap is reserved between two middle beams connected with the upper triangular structure and the lower triangular structure, the upper triangular structure and the lower triangular structure generate radial and circumferential displacement after the foil bears a load, the two middle beams are bent inwards and deformed, the upper triangular structure rotates leftwards or rightwards according to the direction of the load, the lower triangular structure is deformed to two sides to transmit the load to the adjacent upper triangular structure and the lower triangular structure, the upper surface of the foil is contacted with the surface of the top foil, and the lower surface of the foil is contacted with the surface of the bearing sleeve; one end of the foil is free, and the other end of the foil is fixed on the bearing sleeve, and the fixing forms can be various fixing forms such as welding, inserting-limiting pins, hinging, screws, sticking and the like.

In one embodiment, the upper and lower triangular structures in the foil may be replaced by structures with upper and lower connections made from sheet metal pressed into other one or a combination of two shapes, such as a polygonal combination.

In one embodiment, the auxiliary supporting foil is formed by pressing a metal plate and consists of an auxiliary supporting vertical beam and a support, the support is inserted into a groove of the bearing sleeve, the auxiliary supporting foil has the effect of a cantilever beam, the supporting effect is improved for the upper triangular structure of the foil, a certain gap is reserved between the auxiliary supporting vertical beams, a certain deformation can be generated after the middle beam of the foil is extruded, and the supporting effect is provided for the middle beam of the foil.

In one embodiment, the top foil is pressed from a metal plate into a circular arc shape, one end of the top foil being free and the other end being fixed to the bearing housing together with the foil ends.

In one embodiment, the bearing sleeve is a circular metal piece, and the inner surface of the bearing sleeve is provided with a linear cutting axial through groove or pin hole, and when the supporting structure is used, the slotted hole is used for fixing the supporting structure and the foil and the top foil, so that the foil and the top foil can be directly welded on the bearing sleeve.

Optionally, a gap is reserved between the upper triangular structure and the lower triangular structure, an auxiliary supporting structure can be placed to improve bending rigidity of the upper triangular structure and the lower triangular structure, the auxiliary supporting structure is formed by pressing and folding metal plates and is placed between the two beams, the gap is reserved between the auxiliary supporting structures, the auxiliary supporting structure can deform towards the middle after being loaded by the two beams, and the lower part of the auxiliary supporting structure is inserted into a groove of the bearing sleeve to be fixed; the auxiliary supporting structure can adopt other materials or structural shapes to realize the supporting effect and the damping effect on the upper triangular structure and the lower triangular structure.

Alternatively, the triangular structures in the foil may be replaced by structures with other shapes of connection between the upper and lower parts, such as the same or different types of shape, by pressing metal plates into the structures: the upper part rectangular-lower part triangular structure can also be made of other materials or 3D printing.

Optionally, the foil is formed by pressing metal, has a certain supporting rigidity, and can be optionally used without auxiliary supporting foil.

Optionally, the foil may be segmented along a circumferential direction to form a multi-lobe bearing structure, or the foil may be segmented along an axial direction and provided with a certain circumferential dislocation angle, which are used for adjusting the distribution of the upper triangle structure and the lower triangle structure.

Optionally, the upper triangular structure and the lower triangular structure can form a distribution form with high axial middle, short two ends or short two ends in the circumferential direction by changing the size of the structure and the distribution form along the axial direction and the circumferential direction, and the distribution form of high circumferential middle and short two ends of each part is used for reasonably distributing the supporting rigidity and the air film thickness distribution of the foil.

Alternatively, the upper triangular structure and the lower triangular structure can be formed into a two-layer structure by reducing the size of a local structure and placing a foil with similar shape below the foil.

The application provides a gas dynamic pressure bearing with a tiltable foil, wherein a plurality of upper and lower triangle structures are connected in parallel to form the foil, the flexible arc-shaped top foil is supported, and the top foil and the foil are fixed on a bearing sleeve together; the middle of the upper triangular structure and the lower triangular structure is provided with a gap, the auxiliary supporting foil is placed in the gap, when the foil bears load, the inclined edge beams of the lower triangular structure move to two sides and transfer the load, and the inclined edge beams of the upper triangular structure move to the middle and rotate by taking the middle beam as a fulcrum, so that the foil has radial displacement and circumferential displacement, the profile distribution of the air film is regulated, and the stability of the system is facilitated.

Drawings

In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a front view of a foil tiltable gas dynamic bearing according to an embodiment of the present application.

Fig. 2 is an exploded view of a gas dynamic bearing with tiltable foil according to an embodiment of the present application.

Fig. 3 is a partial enlarged view of a foil of a gas dynamic bearing with a tiltable foil according to an embodiment of the present application.

Fig. 4 is a schematic diagram of a top foil of a gas dynamic bearing with a tiltable foil.

Fig. 5 is a partial enlarged view of an auxiliary support foil of a foil tiltable gas dynamic bearing according to an embodiment of the present application.

Fig. 6 is a schematic view of a bearing housing of a foil tiltable gas dynamic bearing according to an embodiment of the present application.

Fig. 7 is a partial enlarged view of a deformation structure of a foil tiltable aerodynamic bearing auxiliary support foil according to an embodiment of the present application.

Fig. 8 is a schematic view of a bearing housing of a foil deformation structure of a foil tiltable pneumatic bearing according to an embodiment of the present application.

Fig. 9 is a front view of a foil bearing without auxiliary support for a foil tiltable gas dynamic bearing in accordance with an embodiment of the present application.

Fig. 10 is an exploded view of a foil bearing without auxiliary support for a foil tiltable gas dynamic bearing according to an embodiment of the present application.

Fig. 11 is an exploded view of a bearing with a foil circumferentially distributed in a gas dynamic bearing with a tiltable foil according to an embodiment of the present application.

Fig. 12 is a front view of a bearing with a foil circumferentially distributed in a gas dynamic bearing with a tiltable foil according to an embodiment of the present application.

Fig. 13 is an exploded view of a bearing with axially distributed foil for a gas dynamic bearing with tiltable foil according to an embodiment of the present application.

Fig. 14 is a front view of a bearing with axially distributed foils for a gas dynamic bearing with tiltable foils according to an embodiment of the present application.

Wherein, the reference numerals in the figures:

1-bearing sleeve, 2-foil, 3-top foil, 4-auxiliary support foil, 5-auxiliary support foil deformation structure, 6-first foil deformation structure, 7-second foil deformation structure, 11-chute of bearing sleeve, 12-pin hole of bearing sleeve, 13-straight slot of bearing sleeve, 21-upper and lower triangle structure, 22-bottom beam, 31-top main body, 32-top foil bending beam, 33-top foil fixing beam, 41-auxiliary support vertical beam, 42-support, 211-top beam of upper triangle structure, 212-side beam of upper triangle structure, 213-middle beam, 214-side beam of lower triangle structure.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be described in detail below. It will be apparent that the described embodiments are only some, but not all, embodiments of the application. All other embodiments, based on the examples herein, which are within the scope of the application as defined by the claims, will be within the scope of the application as defined by the claims.

In the description of the present application, it should be noted that, unless otherwise indicated, the meaning of "a number" means two or more than two; the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship based on that shown in the drawings, merely to facilitate description of the application and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the application. Furthermore, the terms "primary," "secondary," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance, and "first," "second," and the like are used for descriptive purposes only, whereby features defining "first," "second," may explicitly or implicitly include one or more such features.

Referring to the drawings, a foil gas bearing provided by an embodiment of the application will now be described.

As shown in fig. 1 and 2, the foil gas bearing comprises: bearing housing 1, foil 2, top foil 3 and auxiliary support foil 4.

As shown in fig. 3, the foil 2 is formed by connecting a plurality of upper and lower triangle structures 21 which are connected in the middle and are pressed by a flanging machine through the whole metal plate in parallel, the adjacent upper and lower triangle structures 21 are connected into a whole through a bottom beam 22, the foil 2 can be of a whole structure or a single structure, wherein the upper triangle structure is reversely connected with the lower triangle structure, a top beam 211 of the upper triangle structure is a plane, a larger contact area can be ensured when the upper triangle structure contacts with a top foil, a side beam 212 of the upper triangle structure is connected with a side beam 214 of the lower triangle structure through a middle beam 213, and a certain gap is reserved between two middle beams 213 connected with the upper and lower triangle structures; after the foil 2 bears the load, the upper and lower triangular structures 21 are displaced radially and circumferentially, the two middle beams 213 are bent and deformed inwards, the upper triangular structures rotate leftwards or rightwards according to the load direction, the movement of top beams 211 of the deformed adjacent upper triangular structures is not interfered with each other, the lower triangular structures deform to two sides to transfer the load to the adjacent upper and lower triangular structures 21, the upper surface of the foil 2 is contacted with the lower surface of the top foil 3, and the lower surface of the foil 2 is contacted with the inner surface of the bearing sleeve 1; one end of the foil 2 is free, and the other end is fixed on the bearing sleeve 1, and the fixing form can be a plurality of fixing forms such as welding, slot-limiting pins, hinging, screws, sticking and the like.

Further, the upper and lower triangular structures 21 in the foil 2 may be replaced by structures with upper and lower connections made by pressing metal plates into other one or a combination of two shapes.

As shown in fig. 4, the top foil 3 is composed of a circular arc-shaped top foil body 31, a top foil bending beam 32 and a top foil fixing beam 33, which are pressed by a metal plate, and the top foil fixing beam 33 is fixed on the bearing housing 1 together with the end of the foil 2.

As shown in fig. 5, the auxiliary supporting foil 4 is formed by pressing and folding metal plates, and is composed of an auxiliary supporting vertical beam 41 and a support 42, wherein the height of the auxiliary supporting vertical beam 41 is larger than that of a side beam 214 of the lower triangle structure and is lower than that of a top beam 211 of the upper triangle structure, and the support 42 is separated to two sides and inserted into a chute 11 in the bearing sleeve 1, so that the movement of the support 42 can be limited, the effect of a cantilever beam is formed, and the supporting effect is improved for the upper triangle structure of the foil 2; the auxiliary support vertical beams 41 have a certain gap, and the intermediate beams 213 bearing the foil can generate a certain deformation after being extruded, so as to provide a supporting effect for the intermediate beams 213 of the foil.

As shown in fig. 6, the bearing sleeve 1 is a circular metal piece, the inner surface is cut into an axial chute 11 by a warp cutting process, and the circumferential distribution of the chute 11 is consistent with the circumferential distribution of the upper and lower triangle structures 21.

As shown in fig. 7, the auxiliary support foil deforming structure 5 may replace the auxiliary support foil 4, the height of which is required to be the same as that of the auxiliary support foil 4, and the structure is fixed in the slot 13 through the shaft, and the bearing sleeve deforming structure is adapted to the auxiliary support structure deforming structure 5, as shown in fig. 8.

Further, the selection of suitable materials, dimensions, may allow the foil 2 to have sufficient structural support rigidity, and the selection of not using an auxiliary support foil 2, as shown in fig. 9 and 10.

Further, the foils 2 may be segmented along the circumferential direction to form a first foil deformation structure 6 with multiple segments, and meanwhile, the circumferentially segmented foils 2 may be kept in a flat state, and then mounted in the bearing sleeve to form a mounting preload effect, as shown in fig. 11 and 12, or the foils may be segmented along the axial direction to form a second foil deformation structure 7, and a certain circumferential dislocation angle is set, as shown in fig. 11 and 14, and two ways are used for adjusting the upper and lower triangle structures to form an axially middle high, two ends short or circumferentially divided into a plurality of parts, each part is circumferentially middle high, and two ends short are distributed, so that the foil support rigidity and the air film thickness distribution are reasonably arranged.

The foregoing description is only a preferred embodiment of the present application and is not intended to limit the present application, but although the present application has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the technical solutions described in the foregoing embodiments, or that equivalents may be substituted for part of the technical features thereof. Any modification, equivalent replacement, variation, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims (10)

1. A foil tiltable gas dynamic bearing comprising: bearing sleeve, foil, auxiliary support foil and top foil; the foil is formed by connecting a plurality of upper triangular structures and lower triangular structures which are connected in the middle and are pressed by a metal plate in parallel, wherein the upper triangular structures are reversely connected with the lower triangular structures, a certain gap is reserved between two middle beams which are connected with the upper triangular structures and the lower triangular structures, the auxiliary supporting foil is arranged between the two middle beams, the two middle beams are bent inwards to deform and squeeze the auxiliary supporting foil after bearing load, certain friction damping is generated, the upper triangular structures influenced by the middle beams rotate leftwards or rightwards according to the load direction, the lower triangular structures deform to two sides and transmit the load to the adjacent upper triangular structures and the lower triangular structures, the upper surface of the foil is in contact with the lower surface of the top foil, and the lower surface of the foil is in contact with the inner surface of the bearing sleeve; the auxiliary supporting foil support is inserted into a chute in the bearing sleeve; the bearing housing supports the foil, the foil supporting the top foil; one end of the foil sheet and one end of the arc-shaped top foil sheet are free, and the other end of the foil sheet and the arc-shaped top foil sheet are fixed on the bearing sleeve together.

2. The foil gas bearing according to claim 1, wherein the foil is formed by connecting a plurality of upper and lower triangular structures which are connected in the middle and are formed by pressing metal plates in parallel, the foil can be of a whole structure or a single structure, wherein the upper triangular structure is reversely connected with the lower triangular structure, a certain gap is reserved between two middle beams connected with the upper and lower triangular structures, the upper and lower triangular structures generate radial and circumferential displacement after the foil bears load, the two middle beams are bent inwards to deform, the upper triangular structure rotates leftwards or rightwards according to the load direction, the lower triangular structure deforms to two sides to transmit the load to the adjacent upper and lower triangular structures, the upper surface of the foil is contacted with the surface of the top foil, and the lower surface of the foil is contacted with the surface of the bearing sleeve; one end of the foil is free, and the other end of the foil is fixed on the bearing sleeve, and the fixing forms can be various fixing forms such as welding, slot-limiting pins, hinging, screws, sticking and the like.

3. Foil gas bearing according to claim 1, wherein the upper and lower triangular structures in the foil can be replaced by structures with upper and lower connections made by metal plates pressed into other one or a combination of two shapes, or by structures with upper and lower triangular structures made by other materials or 3D printing.

4. The foil gas bearing according to claim 1, wherein the auxiliary support foil is formed by pressing a metal plate and comprises an auxiliary support vertical beam and a support, the support is inserted into a groove of the bearing sleeve, the auxiliary support foil has the effect of a cantilever beam, the support effect is improved for an upper triangular structure of the foil, a certain gap is arranged between the auxiliary support vertical beams, a certain deformation can be generated after the intermediate beam bearing the foil is pressed, and the support effect is provided for the intermediate beam of the foil.

5. The foil gas bearing according to claim 1, wherein a gap is left between the upper and lower triangular structures, an auxiliary supporting foil deformation structure can be placed for improving bending rigidity of the upper and lower triangular structures, the auxiliary supporting foil deformation structure is formed by pressing and folding metal plates, the auxiliary supporting foil deformation structure is placed between the two beams, a gap is left between the supporting structures, the auxiliary supporting foil deformation structure can deform after being loaded by the two middle beams, and the lower part of the auxiliary supporting structure is inserted into a groove of the bearing sleeve for fixing; the auxiliary supporting structure can adopt other materials or structural shapes to realize the supporting effect and the damping effect on the upper triangular structure and the lower triangular structure.

6. The foil gas bearing of claim 1, wherein the foil is stamped from metal and has a support stiffness that is selected without the use of an auxiliary support foil.

7. A foil gas bearing according to claims 1 to 3, wherein the foil may be segmented circumferentially to form a multi-lobed foil variant, or the foil may be segmented axially and provided with a circumferential offset angle, both for adjusting the distribution of the upper and lower triangular structures.

8. A foil gas bearing according to claims 1 to 3, wherein the upper and lower triangular structures are formed by changing the size of the structures and the distribution form along the axial direction and the circumferential direction, and are divided into a plurality of parts in the axial direction, wherein each part is distributed in the circumferential direction, the middle of each part is high, and the two ends are short, so that the reasonable arrangement of the foil support rigidity and the distribution of the gas film thickness can be realized.

9. Foil gas bearing according to claim 1, wherein the top foil is pressed from a metal plate into a circular arc shape, one end of the top foil being free and the other end being fixed to the bearing housing together with the foil end.

10. The foil gas bearing of claim 1, wherein the bearing housing is a circular metal piece, and the bearing housing inner surface is provided with axial through slots or pin holes, and when the auxiliary support foil is used, the slots are used for fixing the auxiliary support foil and the top foil, and the foil and the top foil can be directly fixed on the bearing housing.