A dynamic and static pressure hybrid gas radial bearing

Abstract

The application relates to a dynamic and static pressure mixed gas radial bearing and belongs to the technical field of air bearings. A shaft sleeve is sleeved in a bearing seat, a limiting portion is arranged outside the shaft sleeve, a limiting groove is arranged on the inner wall of the bearing seat in correspondence with the limiting portion; in the radial direction, a wave foil assembly is arranged between the shaft sleeve and the bearing seat, and in the circumferential direction, the wave foil assembly is arranged between the limiting portions at intervals; a plurality of first air inlet holes are arranged on the bottom of the limiting groove, a plurality of second air inlet holes are arranged on the limiting portion, and the positions of the first air inlet holes and the second air inlet holes correspond to each other. The design can guarantee the integrity of the wave foil assembly, the structure is simple, and the wave foil assembly is convenient to process, install and disassemble. When the rotor speed is low, a gas film is formed by the static pressure gas, and the load capacity of the dynamic and static pressure mixed gas radial bearing is enhanced. When the rotor speed is high, dynamic pressure is generated on the basis of the static pressure, and the superposition of the dynamic pressure and the static pressure makes the dynamic and static pressure mixed gas radial bearing have greater load capacity.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of dynamic static pressure mixed gas radial bearing, belongs to air foil bearing technical field. BACKGROUND

[0002] Foil gas bearing is a kind of sliding bearing using gas as lubricant, air is often used as lubricant.Gas bearing can be divided into dynamic gas bearing, static pressure gas bearing and dynamic static pressure mixed gas bearing according to the generation principle of bearing capacity.Dynamic gas bearing does not need external gas supply, and the rotor is suspended by the dynamic pressure effect generated when the rotor rotates at high speed;However, dynamic gas bearing has poor stability when running at high speed, and the bearing capacity is limited, which limits its more extensive application.Static pressure gas bearing is supplied with high-pressure gas between the top foil and the rotor in the bearing through external gas supply, so as to generate gas film and suspend the rotor;However, static pressure gas bearing has low bearing capacity and large static pressure gas consumption.

[0003] By combining gas dynamic pressure bearing and gas static pressure bearing to form dynamic static pressure gas bearing, the problem of low bearing capacity of dynamic pressure gas bearing can be well compensated.In the existing dynamic static pressure gas bearing structure, the wave foil is located between the shaft sleeve and the bearing seat, and a gas pipeline connected with the high-pressure gas source is usually designed on the wave foil, which is relatively complex in design and installation, and in use, the wave foil moves along the circumferential direction under the extrusion of gas film, and the existing design of gas pipeline will inevitably affect the normal work of the wave foil. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides a dynamic static pressure mixed gas radial bearing, the shaft sleeve is sleeved in the inside of the bearing seat, and at least two limiting portions are provided on the outside of the shaft sleeve, and limiting grooves are correspondingly provided on the inner wall of the bearing seat;The external high-pressure gas source enters the gap between the rotor and the shaft sleeve through the first gas inlet hole opened on the bearing seat, the second gas inlet hole and the third gas inlet hole on the shaft sleeve.The design can ensure the integrity of the wave foil assembly, and the structure is simple, convenient to process and install, and also convenient to disassemble.When the rotor speed is low, the static pressure gas forms a gas film, which can reduce the friction power consumption and enhance the bearing capacity of the bearing.When the rotor speed rises to a certain value, the bearing will generate dynamic pressure on the basis of static pressure, and the superposition of dynamic pressure and static pressure makes the dynamic static pressure mixed gas radial bearing have greater bearing capacity.

[0005] The technical scheme of the present application is as follows:

[0006] A dynamic static pressure mixed gas radial bearing, comprising a bearing seat, a shaft sleeve and a plurality of wave foil assemblies;

[0007] The shaft sleeve is sleeved in the inside of the bearing seat, and at least two limiting portions are provided on the outside of the shaft sleeve, and limiting grooves are correspondingly provided on the inner wall of the bearing seat;

[0008] The wave foil assembly is arranged between the shaft sleeve and the bearing seat in the radial direction, and is arranged between the limiting portions in the circumferential direction;

[0009] The bottom of the limiting groove is provided with a plurality of first air inlet holes, the limiting portion is provided with a plurality of second air inlet holes, and the bearing is further provided with an air inlet connector which is in communication with the first air inlet holes and the second air inlet holes;

[0010] The shaft sleeve is further provided with third air inlet holes, and the second air inlet holes are in communication with the third air inlet holes.

[0011] According to the application, the wave foil assembly comprises a bottom foil, and the inner side of the bottom foil is arranged with one or more single-layer wave foils in the axial direction, and one end of the single-layer wave foil is a fixed end, and the other end is a free end.

[0012] Alternatively, the inner side of the bottom foil is arranged with one or more double-layer wave foils in the axial direction, and one end of the double-layer wave foil is a fixed end, and the other end is a free end.

[0013] According to the application, the double-layer wave foil comprises a first wave foil and a second wave foil arranged in layers, and the second wave foil and the first wave foil are arranged in layers from inside to outside on the bottom foil, and the two ends of the first wave foil and the two ends of the second wave foil are fixed together.

[0014] According to the application, the first wave foil comprises a plurality of first circular arcs and second circular arcs connected in sequence, and the radius of the first circular arc is greater than that of the second circular arc.

[0015] The second wave foil comprises a plurality of third circular arcs and fourth circular arcs connected in sequence, and the third circular arc and the second circular arc have the same structure, and the fourth circular arc and the first circular arc have the same structure.

[0016] According to the application, a first connecting portion is arranged between the first circular arc and the second circular arc, and a second connecting portion is arranged between the third circular arc and the fourth circular arc; and the first circular arc is overlapped on the upper part of the third circular arc and the second connecting portions on both sides of the third circular arc, and the second circular arc and the first connecting portions on both sides of the second circular arc are overlapped on the upper part of the fourth circular arc.

[0017] According to the application, the first air inlet holes have a larger diameter than the second air inlet holes, and the second air inlet holes have a larger diameter than the third air inlet holes.

[0018] According to the application, the air inlet connector penetrates the first air inlet holes, and the end of the air inlet connector is threadedly connected with the inner wall of the second air inlet holes.

[0019] According to the application, one end of the bearing seat is provided with a rear end cover fixed on the bearing seat by bolts, and the other end of the bearing seat is provided with a check ring for limiting the wave foil assembly in the axial direction.

[0020] According to the application, two second air inlet holes are arranged on the limiting part, an air passage groove is arranged on the bottom surface of the limiting part, and the air passage groove is communicated with the adjacent second air inlet holes, so that a part of the external high-pressure gas source is branched into the air passage groove; and one first heat dissipation groove is arranged on one side of the air passage groove.

[0021] According to the application, a second heat dissipation groove is further arranged on one side of the air outlet end of the second air inlet hole, and the first heat dissipation groove and the second heat dissipation groove are both arranged on one side of the limiting part close to the fixed end of the double-layer wave foil or the single-layer wave foil. The first heat dissipation groove and the second heat dissipation groove are used for heat dissipation of the wave foil assembly.

[0022] The application has the following beneficial effects:

[0023] 1. In the application, the wave foil assembly adopts a split design, is limited in the circumferential direction by the limiting part, is limited in the radial direction by the shaft sleeve and the bearing seat, and is limited in the front-rear direction by the check ring and the rear end cover respectively.

[0024] 2. The first air inlet hole on the limiting groove, the second air inlet hole on the limiting part and the third air inlet hole on the shaft sleeve form an air inlet channel, which eliminates the interference of the traditional air passage on the wave foil movement and is beneficial to the stable operation of the wave foil assembly. The high-pressure gas source enters the gap between the rotor and the dynamic-static pressure mixed gas radial bearing through the air inlet channel. When the rotor speed is low, the static pressure gas forms a gas film, which can reduce the friction power consumption and enhance the load capacity of the dynamic-static pressure mixed gas radial bearing. When the rotor speed rises to a certain value, the dynamic-static pressure mixed gas radial bearing will generate dynamic pressure on the basis of static pressure. The dynamic pressure and static pressure synergistically act to make the dynamic-static pressure mixed gas radial bearing have greater load capacity.

[0025] 3. When the double-layer wave foil structure is adopted, the large and small circular arcs in the double-layer wave foil structure are alternately stacked, which enhances the elastic support and damping of the wave foil structure and further enhances the load capacity of the dynamic-static pressure mixed gas radial bearing.

[0026] 4. The air passage groove, the first heat dissipation groove and the second heat dissipation groove arranged in the limiting part can branch a small part of the external high-pressure gas into the mounting space of the wave foil assembly, thereby improving the heat dissipation effect of the wave foil assembly. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The application provides a structural schematic diagram of the dynamic-static pressure mixed gas radial bearing.

[0028] Figure 2 An explosion schematic diagram of the dynamic and static pressure mixed gas radial bearing provided by the present application.

[0029] Figure 3 A structural schematic diagram of the bearing seat provided by the present application.

[0030] Figure 4 A structural schematic diagram of the shaft sleeve provided by the present application.

[0031] Figure 5 A view of the dynamic and static pressure mixed gas radial bearing provided by the present application.

[0032] Figure 6 A cross-sectional schematic diagram in A-A direction. Figure 5

[0033] Figure 7 A structural schematic diagram of the wave foil assembly with double-layer wave foil structure provided by the present application.

[0034] Figure 8 A cross-sectional schematic diagram of the single-piece double-layer wave foil provided by the present application.

[0035] Figure 9 A structural schematic diagram of the limiting part provided by the present application.

[0036] 1, bearing seat, 2, shaft sleeve, 3, wave foil assembly, 4, limiting part, 5, limiting groove, 6, first air inlet hole, 7, second air inlet hole, 8, third air inlet hole, 9, bottom foil, 10, double-layer wave foil, 11, first wave foil, 12, second wave foil, 13, first circular arc, 14, second circular arc, 15, third circular arc, 16, fourth circular arc, 17, first connecting part, 18, second connecting part, 19, air inlet joint, 20, rear end cover, 21, retainer, 22, bolt, 23, air passage groove, 24, second heat dissipation groove, 25, first heat dissipation groove. DETAILED DESCRIPTION

[0037] The technical solutions of the present application will be described below in the drawings to make the present application clear and complete, which form a part of the present application. The drawings are used to provide further understanding of the present application, and the schematic embodiments and the description are used to explain the present application and do not constitute an improper limitation on the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0038] It should be noted that, unless the directions are defined separately, the directions such as up, down, left, right and the like mentioned in the present application are relative to the directions of the embodiments of the present application. Figure 2 ​The directions of up, down, left, right and the like shown are correct, and if the specific posture changes, the directional indications also change accordingly. The "first", "second" and similar words used in the present application do not represent any order, quantity or importance, but are only used to distinguish different components. In addition, in various embodiments of the present disclosure, the same or similar reference signs represent the same or similar components.

[0039] In the present application, unless otherwise explicitly specified and limited, the terms "connection", "fixation" and the like should be understood broadly, for example, "connection" can be fixed connection, or detachable connection, or one body, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0040] In addition, the technical solutions of various embodiments of the present application can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor is it within the scope of the present application.

[0041] Embodiment 1

[0042] The present embodiment provides a dynamic and static pressure mixed gas radial bearing, as shown in Figure 1 、 Figure 2 、 Figure 3 and Figure 4 , comprising a bearing seat 1, a shaft sleeve 2 and a plurality of wave foil assemblies 3;

[0043] The shaft sleeve 2 is sleeved inside the bearing seat 1, and the outer part of the shaft sleeve 2 is provided with at least two limiting parts 4, and the inner wall of the bearing seat 1 is correspondingly provided with a limiting groove 5; specifically, two, three, four or more limiting parts 4 can be provided according to requirements, and the drawings of the present patent take four limiting parts 4 as an example for illustration.

[0044] In the radial direction, the wave foil assembly 3 is arranged between the shaft sleeve 2 and the bearing seat 1, and in the circumferential direction, the wave foil assembly 3 is arranged between the limiting parts 4; the wave foil assembly 3 forms an unsealed ring along the circumferential direction, and the space for the wave foil assembly 3 to move along the circumferential direction is provided between the adjacent limiting parts 4; when the gas film extrudes the wave foil assembly 3, the wave foil assembly 3 will be flattened to a certain extent.

[0045] The bottom of the limiting groove 5 is provided with a plurality of first air inlet holes 6, and the limiting part 4 is provided with a plurality of second air inlet holes 7, and the shaft sleeve 2 is further provided with an air inlet joint 19, which communicates the first air inlet hole 6 and the second air inlet hole 7;

[0046] The shaft sleeve 2 is further provided with a third air inlet hole 8, and the second air inlet hole 7 and the third air inlet hole 8 are in communication.

[0047] A plurality of first air inlet holes 6 are formed in the bearing seat 1 along the axial direction of the radial bearing. The embodiment is described by taking two first air inlet holes 6 as an example. Similarly, the number of the second air inlet holes 7 and the third air inlet holes 8 is the same as that of the first air inlet holes 6.

[0048] The installation and working process of the above dynamic and static pressure mixed gas radial bearing is as follows:

[0049] The wave foil assembly 3 and the shaft sleeve 2 are sequentially installed on the inner side of the bearing seat 1, and a high-pressure gas source is connected to the air inlet end of the air inlet joint 19.

[0050] The high-pressure gas output from the air outlet end of the air inlet joint 19 enters the gap between the dynamic and static pressure mixed gas radial bearing and the rotor. For a rotor operating at low speed, the high-pressure gas source forms a gas film between the dynamic and static pressure mixed gas radial bearing and the rotor, supporting the rotor to float. When the rotor reaches a certain speed, the dynamic and static pressure mixed gas radial bearing will also generate dynamic pressure on the basis of static pressure, and the superposition of dynamic pressure and static pressure makes the dynamic and static pressure mixed gas radial bearing have greater carrying capacity.

[0051] Embodiment 2

[0052] The embodiment provides a dynamic and static pressure mixed gas radial bearing, which is different from the embodiment 1 in that:

[0053] The wave foil assembly 3 comprises a bottom foil 9, and one or more single-layer wave foils are arranged on the inner side of the bottom foil 9 along the axial direction. One end of the single-layer wave foil is a fixed end and is fixed to the bottom foil 9, and the other end of the single-layer wave foil is a free end.

[0054] Alternatively, one or more double-layer wave foils 10 are arranged on the inner side of the bottom foil 9 along the axial direction. One end of the double-layer wave foil 10 is a fixed end and is fixed to the bottom foil 9, and the other end of the double-layer wave foil 10 is a free end.

[0055] When only one single-layer wave foil or double-layer wave foil 10 is arranged, the single-layer wave foil or double-layer wave foil 10 is in an integral structure. When a plurality of single-layer wave foils or double-layer wave foils 10 are arranged, the single-layer wave foils or double-layer wave foils 10 are sequentially arranged on the inner side of the bottom foil 9.

[0056] Embodiment 3

[0057] The embodiment provides a dynamic and static pressure mixed gas radial bearing, which is different from the embodiment 2 in that:

[0058] As Figure 5 , Figure 7 and Figure 8As shown, the double-layer corrugated foil 10 includes a first corrugated foil 11 and a second corrugated foil 12 stacked together, and the second corrugated foil 12 and the first corrugated foil 11 are stacked sequentially from the inside to the outside on the bottom foil 9. The two ends of the first corrugated foil 11 are fixed together with the two ends of the second corrugated foil 12.

[0059] Example 4

[0060] This embodiment provides a radial bearing for a mixture of dynamic and static pressure gases, which differs from Embodiment 3 in that:

[0061] like Figure 5 , Figure 7 and Figure 8 As shown, the first wave foil 11 includes several first arcs 13 and second arcs 14 connected in sequence, and the radius of the first arc 13 is greater than the radius of the second arc 14;

[0062] The second wave foil 12 includes several third arcs 15 and fourth arcs 16 connected in sequence, and the third arc 15 has the same structure as the second arc 14, and the fourth arc 16 has the same structure as the first arc 13.

[0063] Example 5

[0064] This embodiment provides a radial bearing for a mixture of hydrostatic and hydrodynamic gases, which differs from Embodiment 4 in that:

[0065] like Figure 7 and Figure 8 As shown, a first connecting portion 17 is provided between the first arc 13 and the second arc 14, and a second connecting portion 18 is provided between the third arc 15 and the fourth arc 16; and the first arc 13 overlaps the third arc 15 and the second connecting portions 18 on both sides of the third arc 15, and the second arc 14 and the first connecting portions 17 on both sides of the second arc 14 overlap the fourth arc 16.

[0066] When the air film compresses the double-layer corrugated foil 10, the first corrugated foil 11 and the second corrugated foil 12 can bear the air film pressure from two directions. Under the action of the first connecting part 17 and the second connecting part 18, the interaction between the various structures of the double-layer corrugated foil 10 forms a gradient support, enabling the air bearing to withstand a greater load.

[0067] Example 6

[0068] This embodiment provides a radial bearing for a mixture of dynamic and static pressure gases, which differs from Embodiment 1 in that:

[0069] like Figure 3 , Figure 4 and Figure 6 As shown, the diameter of the first air intake 6 is larger than the diameter of the second air intake 7. The diameter of the second air intake 7 is larger than the diameter of the third air intake 8.

[0070] When the rotor rotates, the shaft sleeve 2 will move along the circumferential direction, and the arrangement can provide space for the circumferential movement of the shaft sleeve 2.

[0071] Embodiment 7

[0072] The embodiment provides a dynamic and static pressure mixed gas radial bearing, which is different from the embodiment 1 in that:

[0073] The air inlet joint 19 penetrates the first air inlet hole 6, and the end of the air inlet joint 19 is threadedly connected with the inner wall of the second air inlet hole 7.

[0074] Embodiment 8

[0075] The embodiment provides a dynamic and static pressure mixed gas radial bearing, which is different from the embodiment 1 in that:

[0076] As shown in Figure 1 , Figure 2 and Figure 3 , one end of the bearing seat 1 is provided with a rear end cover 20, the rear end cover 20 is fixed on the bearing seat 1 through bolts 22, and the other end of the bearing seat 1 is provided with a check ring 21 for limiting the wave foil assembly 3 in the axial direction.

[0077] Embodiment 9

[0078] The embodiment provides a dynamic and static pressure mixed gas radial bearing, which is different from the embodiment 2 in that:

[0079] As shown in Figure 9 , two second air inlet holes 7 are arranged on the limiting portion 4, an air passage groove 23 is arranged on the bottom surface of the limiting portion 4, the limiting portion 4 is welded to the outside of the shaft sleeve 2, and the bottom surface of the limiting portion 4 contacts the outside of the shaft sleeve 2, and the air passage groove 23 is communicated with adjacent second air inlet holes 7, so that after the high-pressure air source flows out through the second air inlet holes 7, a part of the high-pressure air source is shunted to the air passage groove 23; one first heat dissipation groove 25 is arranged on one side of the air passage groove 23.

[0080] Embodiment 10

[0081] The embodiment provides a dynamic and static pressure mixed gas radial bearing, which is different from the embodiment 9 in that:

[0082] As shown in Figure 9 , a second heat dissipation groove 24 is further arranged on one side of the gas outlet end of the second air inlet hole 7, and the first heat dissipation groove 25 and the second heat dissipation groove 24 are both arranged on one side of the limiting portion 4 close to the fixed end of the double-layer wave foil 10 or the single-layer wave foil. The first heat dissipation groove 25 and the second heat dissipation groove 24 are used for heat dissipation of the wave foil assembly 3.

[0083] The size of the ventilation groove 23, the first heat dissipation groove 25 and the second heat dissipation groove 24 is far less than the diameter of the second air inlet hole 7, and can be set according to requirements.

[0084] A small part of the high-pressure gas output from the air outlet end of the air inlet joint 19 is discharged through the second heat dissipation groove 24 of the second air inlet hole 7 and the first heat dissipation groove 25 of the ventilation groove 23, so as to achieve heat dissipation of the wave foil assembly.

[0085] The above description shows and describes the preferred embodiments of the present application, but as previously noted, the present application is not limited to the forms disclosed herein, should not be considered as excluding other embodiments, and can be used in various other combinations, modifications and environments, and can be modified within the scope of the objects described herein, by the above teaching or related technical or knowledge. The modifications and changes made by those skilled in the art without departing from the spirit and scope of the present application shall fall within the protection scope of the claims appended to the present application.

Claims

1. A radial bearing for a mixture of hydrostatic and hydrodynamic gases, characterized in that, Includes bearing housing, bushing, and several corrugated foil assemblies; The bushing is fitted inside the bearing housing, and at least two limiting parts are provided on the outside of the bushing, and corresponding limiting grooves are provided on the inner wall of the bearing housing; In the radial direction, the corrugated foil assembly is positioned between the bushing and the bearing seat; in the circumferential direction, the corrugated foil assembly is spaced apart between the limiting parts. The corrugated foil assembly includes a bottom foil, and the inner side of the bottom foil is provided with one or more single-layer corrugated foils along the axial direction, with one end of the single-layer corrugated foil being a fixed end and the other end being a free end; or, the inner side of the bottom foil is provided with one or more double-layer corrugated foils along the axial direction, with one end of the double-layer corrugated foil being a fixed end and the other end being a free end. One end of the bearing housing is provided with a rear end cover, and the other end of the bearing housing is provided with a retaining ring, which is used to limit the corrugated foil assembly in the axial direction; The bottom of the limiting groove is provided with several first air inlets, the limiting part is provided with several second air inlets, the bearing is also provided with an air inlet connector, the air inlet connector passes through the first air inlet and connects the first air inlet and the second air inlet, the bushing is also provided with a third air inlet, the second air inlet and the third air inlet are connected to form a static pressure supply path from the bearing seat to the bushing. The end of the air intake connector is threaded to the inner wall of the second air intake hole; The diameter of the first air intake is larger than the diameter of the second air intake, and the diameter of the second air intake is larger than the diameter of the third air intake. Two second air inlets are provided on the limiting part, and a ventilation groove is opened on the bottom surface of the limiting part. The ventilation groove is connected to the adjacent second air inlets, and at least one first heat dissipation groove is provided on one side of the ventilation groove. A second heat dissipation groove is also provided on one side of the air outlet end of the second air inlet, and both the first and second heat dissipation grooves are opened on the side of the limiting part near the fixed end of the double-layer corrugated foil or the single-layer corrugated foil.

2. The radial bearing for a hydrostatic / hydrodynamic mixed gas according to claim 1, characterized in that, The double-layered corrugated foil includes a first corrugated foil and a second corrugated foil stacked together, with the second corrugated foil and the first corrugated foil stacked sequentially from the inside out on the bottom foil, and the two ends of the first corrugated foil being fixed together with the two ends of the second corrugated foil.

3. The radial bearing for a hydrostatic / hydrodynamic mixed gas according to claim 2, characterized in that, The first wave of foil includes several first arcs and second arcs connected in sequence, and the radius of the first arc is greater than the radius of the second arc; The second wave foil includes several third and fourth arcs connected in sequence, with the third arc having the same structure as the second arc and the fourth arc having the same structure as the first arc.

4. A radial bearing for a mixture of hydrostatic and hydrodynamic gases according to claim 3, characterized in that, A first connecting portion is provided between the first arc and the second arc, and a second connecting portion is provided between the third arc and the fourth arc; and the first arc overlaps the upper part of the third arc and the second connecting portions on both sides of the third arc, and the second arc and the first connecting portions on both sides of the second arc overlap the upper part of the fourth arc.

5. A radial bearing for a mixture of hydrostatic and hydrodynamic gases according to claim 1, characterized in that, The rear end cover is fixed to the bearing housing with bolts.

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