阅读说明：本技术 一种箔片动压轴承、浇注模具及轴系 (Foil dynamic pressure bearing, casting mold and shaft system ) 是由 聂慧凡 张彪 赵俊志 毕刘新 侯炎恒 于 2021-11-18 设计创作，主要内容包括：本发明提供一种箔片动压轴承、浇注模具及轴系,箔片动压轴承包括顶箔、波箔和粘弹性筒体,波箔和粘弹性筒体环绕顶箔设置；顶箔与粘弹性筒体相连,顶箔用于支撑转轴；至少部分波箔嵌于粘弹性筒体内以使粘弹性筒体随波箔变形；粘弹性筒体用于约束顶箔和波箔,并与轴承座相连。顶箔、波箔和粘弹性筒体连为一体,将粘弹性筒体装配在轴承座上,即可完成箔片动压轴承与轴承座的安装。采用粘弹性筒体取代轴承套筒,能够节约轴承套筒的加工费用,大大降低了箔片动压轴承的加工成本。此外,波箔弹性变形时也会带动相邻的粘弹性筒体压缩或者拉伸,阻尼性能大大提升,从而能够迅速消耗转子-轴承系统振动时的机械能,有效抑制转子-轴承系统的振动。(The invention provides a foil dynamic pressure bearing, a casting mold and a shaft system, wherein the foil dynamic pressure bearing comprises a top foil, a bump foil and a viscoelastic cylinder body, wherein the bump foil and the viscoelastic cylinder body are arranged around the top foil; the top foil is connected with the viscoelastic cylinder and used for supporting the rotating shaft; at least part of the wave foil is embedded in the viscoelastic cylinder body so that the viscoelastic cylinder body deforms along with the wave foil; the viscoelastic cylinder is used to constrain the top and wave foils and is attached to the bearing block. The top foil, the corrugated foil and the viscoelastic cylinder are connected into a whole, and the viscoelastic cylinder is assembled on the bearing seat, so that the foil dynamic pressure bearing and the bearing seat can be installed. The viscoelastic cylinder is adopted to replace a bearing sleeve, so that the processing cost of the bearing sleeve can be saved, and the processing cost of the foil dynamic pressure bearing is greatly reduced. In addition, the wave foil can drive the adjacent viscoelastic cylinder to compress or stretch when elastically deforming, and the damping performance is greatly improved, so that the mechanical energy of the rotor-bearing system during vibration can be quickly consumed, and the vibration of the rotor-bearing system can be effectively inhibited.)

1. A foil hydrodynamic bearing comprising a top foil, a bump foil and a viscoelastic cylinder, the bump foil and the viscoelastic cylinder being disposed around the top foil;

the top foil is connected with the viscoelastic cylinder and is used for supporting the rotating shaft;

at least a portion of the bump foil is embedded within the viscoelastic cylinder such that the viscoelastic cylinder deforms with the bump foil;

the viscoelastic cylinder is used for restraining the top foil and the wave foil and is connected with the bearing seat.

2. The foil hydrodynamic bearing of claim 1, wherein the top foil includes a support portion for supporting the shaft and a fixing portion having one side connected to the support portion and the other side embedded in the viscoelastic cylinder;

the wave foil is arranged around the supporting part of the top foil, and one side of the wave foil, which is opposite to the supporting part, is embedded in the viscoelastic cylinder.

3. The foil hydrodynamic bearing of claim 2 wherein the bump foil includes an arcuate section, a connecting section, and a raised section;

the arched sections and the connecting sections are alternately arranged along the circumferential direction of the viscoelastic cylinder body, the arched sections are abutted against the supporting part, and the connecting sections are embedded in the viscoelastic cylinder body;

the heightening section is positioned between the adjacent arch section and the connecting section, one side of the heightening section, which is close to the supporting part, is connected with the arch section, one side of the heightening section, which is far away from the supporting part, is connected with the connecting section, and at least part of the heightening section is embedded in the viscoelastic cylinder.

4. The foil hydrodynamic bearing of claim 3, wherein the viscoelastic cylinder comprises a first filler, a second filler and a coupling;

the first filling part is positioned between two adjacent heightening sections and positioned on one side of the arch section, which faces away from the supporting part;

the second filling part is positioned between two adjacent heightening sections and positioned on one side of the connecting section facing the supporting part;

the coupling portion is located at least one end of the first filling portion and the second filling portion in the axial direction of the viscoelastic cylinder, and the coupling portion is connected to both the first filling portion and the second filling portion.

5. The foil hydrodynamic bearing of claim 4, wherein the viscoelastic cylinder further comprises an axial positioning projection connected to a side of the first filler portion facing away from the arcuate segment, the axial positioning projection for engaging an inner wall of the bearing seat.

6. The foil hydrodynamic bearing of claim 5 wherein the axial locating projection surrounds the bump foil periphery and is simultaneously connected to each of the first filler portions.

7. Foil hydrodynamic bearing according to claim 4, characterized in that the side of the first filling portion facing away from the bearing portion is aligned with the side of the connecting section facing away from the bearing portion.

8. The foil hydrodynamic bearing of claim 4, wherein a first cooling channel is provided between the first filler and the segment and a second cooling channel is provided between the second filler and the bearing.

9. A casting mold for manufacturing a foil hydrodynamic bearing according to any one of claims 1 to 8, comprising a mold body and a positioning member;

the die body is provided with a cavity for accommodating the top foil and the corrugated foil;

the positioning piece is cylindrical, one end of the positioning piece is provided with a plurality of avoiding grooves, and the avoiding grooves are respectively clamped with the corrugated foil;

and a pouring cavity is formed between the die body and the positioning piece so as to cast and mold the viscoelastic cylinder.

10. A shafting comprising a shaft, a bearing housing and a foil hydrodynamic bearing as claimed in any one of claims 1 to 8, said shaft being disposed through said top foil and said viscoelastic cylinder being connected to said bearing housing.

Technical Field

The invention relates to the field of bearings, in particular to a foil dynamic pressure bearing, a casting mold and a shaft system.

Background

The common foil dynamical pressure air bearing comprises a top foil, an elastic foil and a bearing sleeve, wherein the top foil and the elastic foil are fixed in the bearing sleeve through a pin to form a complete bearing product, and the bearing sleeve is installed in a bearing seat of a machine.

When the foil dynamical pressure air bearing is processed, the assembly relation between the bearing sleeve and the bearing seat needs to be considered to ensure that the assembly meets the process requirements of equipment, so the requirements on the dimensional tolerance and the form and position tolerance of the bearing sleeve are very high, the processing cost of the bearing sleeve accounts for about 40% of the cost of a single bearing, and the processing cost of the foil dynamical pressure air bearing is high.

In addition, the foil dynamical pressure air bearing only consisting of the top foil, the elastic foil and the bearing sleeve has limited damping performance, is difficult to timely consume mechanical energy when the rotor-bearing system vibrates, and has insufficient capability of inhibiting the rotor-bearing system from vibrating.

Disclosure of Invention

In order to solve the problems of the prior art, it is an object of the present invention to provide a foil dynamic pressure bearing.

The invention provides the following technical scheme:

a foil hydrodynamic bearing comprising a top foil, a bump foil and a viscoelastic cylinder, the bump foil and the viscoelastic cylinder being disposed around the top foil;

the top foil is connected with the viscoelastic cylinder and is used for supporting the rotating shaft;

at least a portion of the bump foil is embedded within the viscoelastic cylinder such that the viscoelastic cylinder deforms with the bump foil;

the viscoelastic cylinder is used for restraining the top foil and the wave foil and is connected with the bearing seat.

As a further optional solution to the foil dynamic pressure bearing, the top foil includes a supporting portion and a fixing portion, the supporting portion is used for supporting the rotating shaft, one side of the fixing portion is connected to the supporting portion, and the other side of the fixing portion is embedded in the viscoelastic cylinder;

the wave foil is arranged around the supporting part of the top foil, and one side of the wave foil, which is opposite to the supporting part, is embedded in the viscoelastic cylinder.

As a further alternative to the foil dynamic pressure bearing, the bump foil includes an arch section, a connecting section, and a heightened section;

the arched sections and the connecting sections are alternately arranged along the circumferential direction of the viscoelastic cylinder body, the arched sections are abutted against the supporting part, and the connecting sections are embedded in the viscoelastic cylinder body;

the heightening section is positioned between the adjacent arch section and the connecting section, one side of the heightening section, which is close to the supporting part, is connected with the arch section, one side of the heightening section, which is far away from the supporting part, is connected with the connecting section, and at least part of the heightening section is embedded in the viscoelastic cylinder.

As a further alternative to the foil dynamic pressure bearing, the viscoelastic cylinder includes a first filling portion, a second filling portion, and a coupling portion;

the first filling part is positioned between two adjacent heightening sections and positioned on one side of the arch section, which faces away from the supporting part;

the second filling part is positioned between two adjacent heightening sections and positioned on one side of the connecting section facing the supporting part;

the coupling portion is located at least one end of the first filling portion and the second filling portion in the axial direction of the viscoelastic cylinder, and the coupling portion is connected to both the first filling portion and the second filling portion.

As a further optional scheme for the foil dynamic pressure bearing, the viscoelastic cylinder further includes an axial positioning protrusion, the axial positioning protrusion is connected to a side of the first filling portion facing away from the arch section, and the axial positioning protrusion is used for being embedded into an inner wall of the bearing seat.

As a further alternative to the foil dynamic pressure bearing, the axial positioning protrusion surrounds the bump foil periphery, and the axial positioning protrusion is simultaneously connected to each of the first filling portions.

As a further alternative to the foil hydrodynamic bearing, a side of the first filling portion facing away from the bearing portion is aligned with a side of the connecting section facing away from the bearing portion.

Optionally, a side of the first filling portion facing away from the support portion is clearance-fitted with an inner wall of the bearing seat.

As a further alternative to the foil dynamic pressure bearing, a first cooling channel is provided between the first filling portion and the arcuate section, and a second cooling channel is provided between the second filling portion and the support portion.

Another object of the present invention is to provide a casting mold.

The invention provides the following technical scheme:

a casting mould for processing the foil dynamic pressure bearing comprises a mould body and a positioning piece;

the die body is provided with a cavity for accommodating the top foil and the corrugated foil;

the positioning piece is cylindrical, one end of the positioning piece is provided with a plurality of avoiding grooves, and the avoiding grooves are respectively clamped with the corrugated foil;

and a pouring cavity is formed between the die body and the positioning piece so as to cast and mold the viscoelastic cylinder.

It is a further object of the present invention to provide a shafting.

The invention provides the following technical scheme:

a shaft system comprises a rotating shaft, a bearing seat and the foil dynamic pressure bearing, wherein the rotating shaft is arranged in the top foil in a penetrating mode, and the viscoelastic cylinder is connected with the bearing seat.

The embodiment of the invention has the following beneficial effects:

the top foil, the corrugated foil and the viscoelastic cylinder are connected into a whole, and the viscoelastic cylinder is assembled on the bearing seat, so that the foil dynamic pressure bearing and the bearing seat can be installed. The viscoelastic cylinder is adopted to replace a bearing sleeve, so that the processing cost of the bearing sleeve can be saved, and the processing cost of the foil dynamic pressure bearing is greatly reduced. In addition, the wave foil can drive the adjacent viscoelastic cylinder to compress or stretch when elastically deforming, and the damping performance is greatly improved, so that the mechanical energy of the rotor-bearing system during vibration can be quickly consumed, and the vibration of the rotor-bearing system can be effectively inhibited.

In order to make the aforementioned objects, features and advantages of the present invention more comprehensible and comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 shows a schematic structural view of a prior art foil hydrodynamic air bearing;

FIG. 2 shows a schematic structural view of a prior art hydrostatic air bearing;

fig. 3 is a front view showing a foil dynamic pressure bearing provided in embodiment 1 of the present invention;

fig. 4 is a front view showing a foil dynamic pressure bearing provided in embodiment 2 of the present invention;

FIG. 5 shows a schematic cross-sectional view A-A of FIG. 4;

fig. 6 is a side view showing a foil dynamic pressure bearing provided in embodiment 2 of the present invention;

FIG. 7 shows a schematic cross-sectional view along B-B of FIG. 6;

FIG. 8 is a front view of a shafting provided in embodiment 2 of the present invention;

FIG. 9 shows a schematic cross-sectional view along line C-C of FIG. 8;

fig. 10 is a front view showing a casting mold provided in embodiment 3 of the present invention;

fig. 11 is a schematic structural diagram illustrating a positioning element in a casting mold according to embodiment 3 of the present invention.

Description of the main element symbols:

100-foil hydrodynamic bearings; 110-top foil; 111-a support portion; 112-a fixed part; 120-wave foil; 121-arch segment; 122-a connecting segment; 123-heightening section; 130-viscoelastic cylinder; 131-a first filling part; 132-a second filling section; 133-a coupling portion; 134-axial positioning projections; 135-a first cooling channel; 136-a second cooling channel; 200-a bearing seat; 210-an air gap; 300-a rotating shaft; 400-casting a mold; 410-a mold body; 420-a positioning member; 500-foil hydrodynamic air bearing; 510-top foil; 520-an elastic foil; 530-bearing sleeve; 600-O-shaped ring.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the templates herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Referring to fig. 1, a conventional foil dynamical pressure air bearing 500 is composed of three parts, i.e., a top foil 510, an elastic foil 520 and a bearing sleeve 530, wherein the top foil 510 and the elastic foil 520 are key parts for damping vibration of a rotating shaft 300, and the bearing sleeve 530 is mainly used for fixedly assembling the top foil 510 and the elastic foil 520. The top foil 510 and the flexible foil 520 are fixed in advance in the bearing sleeve 530 by the bearing manufacturer by pins, and are delivered to customers as a complete bearing product after being assembled. The foil dynamical air bearing 500 is received by the customer and then installed in the bearing housing 200 of the machine.

Due to the existence of the bearing sleeve 530, the size chain of the bearing seat 200, the elastic foil 520, the top foil 510 and the rotating shaft 300 is additionally provided with a size ring, and the assembly relationship between the bearing sleeve 530 and the bearing seat 200 needs to be additionally considered to ensure that the assembly meets the process requirements of equipment. In general, the dimensional and form tolerances of the bearing sleeve 530 are very high, and the machining cost of the bearing sleeve 530 is about 40% of the cost of a single bearing, which ultimately results in high machining cost of the foil dynamical pressure air bearing 500.

In addition, the foil dynamical pressure air bearing 500 composed of only the top foil 510, the elastic foil 520 and the bearing sleeve 530 has a limited damping performance, it is difficult to timely consume mechanical energy when the rotor-bearing system vibrates, and the ability to suppress the vibration of the rotor-bearing system is insufficient.

To enhance the damping performance of the foil dynamical pressure air bearing 500, a viscoelastic material with high damping is initially disposed between the elastic foil 520 and the top foil 510, or between the elastic foil 520 and the bearing sleeve 530, or between the top foil 510 and the bearing sleeve 530. The external load is made by radially extruding the viscoelastic material, and mechanical energy is consumed by using the hysteresis rebound characteristic of the viscoelastic material to generate damping and inhibit the vibration of the rotor-bearing system.

However, the gap of the foil hydrodynamic air bearing 500 may be limited by the thickness dimension and tolerance of the viscoelastic material. From the perspective of production and processing, due to the technical problem of the viscoelastic material itself, the dimensional tolerance cannot be effectively guaranteed, and the gaps of the same batch of foil dynamic pressure air bearings 500 are often different in size. From the perspective of long-term use, most of the viscoelastic materials are rubber pieces, and are prone to aging and degeneration, so that gaps and performance of the foil hydrodynamic air bearing 500 cannot be maintained for a long time.

Meanwhile, there is no connection between the viscoelastic material and the elastic foil 520, the top foil 510, or the bearing sleeve 530, and thus the viscoelastic material needs to be axially and circumferentially positioned, which is generally performed by sealing the viscoelastic material with end caps at both ends of the foil dynamical pressure air bearing 500. This causes the axial cooling channels of the elastic foils 520 to be completely blocked, and the cooling air flow cannot timely take away the heat generated by the foil dynamical pressure air bearing 500, which easily causes the foil dynamical pressure air bearing 500 to be overheated and fail.

Similarly, the viscoelastic material, the elastic foil 520 and the top foil 510 are not closely connected, damping can be generated only by extruding the viscoelastic material, the stretching-compressing hysteresis energy consumption capability of the viscoelastic material under the action of external load cannot be fully exerted, the envelope area of a formed hysteresis curve is small, and the damping effect is poor.

Referring to fig. 2, in the conventional static pressure air bearing, an O-ring 600 is installed between a bearing sleeve 530 and a bearing housing 200, so as to improve the stability of the rotor-bearing system. The above foil dynamical pressure air bearing 500 generally has a problem of poor stability, and in order to increase the stability of the rotor-bearing system, the static pressure air bearing may be referred to, and an O-ring 600 is added between the bearing sleeve 530 and the bearing seat 200 to absorb and suppress vibration, so as to improve the stability of the device. However, this method requires additional procurement of custom O-rings 600, which increases costs.

Example 1

Referring to fig. 3, the present embodiment provides a foil hydrodynamic bearing 100, and more particularly, to a foil hydrodynamic bearing 100 without a bearing sleeve 530 and with enhanced system stability, which is particularly suitable for a rotating mechanical shaft system with high rotation speed, light load and no oil condition, and can operate in both high-temperature and low-temperature environments.

Specifically, the foil dynamic pressure bearing 100 includes a top foil 110, a bump foil 120, and a viscoelastic cylinder 130. The top foil 110 is connected to the viscoelastic cylinder 130, and at least part of the wave foil 120 is embedded in the viscoelastic cylinder 130.

The top foil 110, the bump foil 120, and the viscoelastic cylinder 130 are connected to form a whole, and the viscoelastic cylinder 130 is assembled on the bearing housing 200, so that the foil hydrodynamic bearing 100 and the bearing housing 200 can be mounted. The viscoelastic cylinder 130 is adopted to replace the bearing sleeve 530, so that the processing cost of the bearing sleeve 530 can be saved, and the processing cost of the foil dynamic pressure bearing 100 is greatly reduced. In addition, the wave foil 120 drives the viscoelastic cylinder 130 to compress or stretch when elastically deforming, so that the damping performance is greatly improved, the mechanical energy of the rotor-bearing system during vibration can be quickly consumed, and the vibration of the rotor-bearing system can be effectively inhibited.

Example 2

Referring to fig. 4 and 5, the present embodiment provides a foil hydrodynamic bearing 100, and more particularly, to a foil hydrodynamic bearing 100 without a bearing sleeve 530 and with enhanced system stability, which includes a top foil 110, a bump foil 120, and a viscoelastic cylinder 130, wherein the top foil 110 and the bump foil 120 are fixed on the viscoelastic cylinder 130, and the three are connected together. The viscoelastic cylinder 130 is assembled on the bearing housing 200, and the foil hydrodynamic bearing 100 and the bearing housing 200 are assembled.

Referring to fig. 6 and 7 together, in particular, the top foil 110 is composed of a supporting portion 111 and a fixing portion 112. The support 111 is disposed along the axial direction of the foil dynamic pressure bearing 100, and is in direct contact with the rotating shaft 300 in use. The cross section of the supporting portion 111 is arc-shaped, the center of the arc is located on the axis of the foil hydrodynamic bearing 100, and the corresponding central angle is slightly smaller than 360 °.

The fixing portion 112 is integrally formed with the support portion 111, and is also provided along the axial direction of the foil dynamic pressure bearing 100. One side of the fixing portion 112 in the width direction is connected to the supporting portion 111, and the other side is embedded in the viscoelastic cylinder 130, so that the entire top foil 110 is fixedly connected to the viscoelastic cylinder 130.

Specifically, the bump foil 120 is composed of a plurality of arcuate sections 121, a heightened section 123, and a connection section 122, and the arcuate sections 121, the heightened section 123, and the connection section 122 are all arranged in the axial direction of the foil dynamic pressure bearing 100. Wherein, the arched section 121 is arched towards the axis of the foil hydrodynamic bearing 100, and the cross section thereof is arc-shaped; the cross section of the heightened section 123 is straight; the connecting section 122 has an arc-shaped cross section, and the center of the arc-shaped cross section is located on the axis of the foil hydrodynamic bearing 100.

The respective arcuate segments 121 and the connecting segments 122 are alternately arranged in the circumferential direction of the foil dynamic pressure bearing 100, and the apexes of the arcuate segments 121 abut against the support portions 111, and the distance between the connecting segments 122 and the support portions 111 is greater than the distance between the arcuate segments 121 and the support portions 111. Accordingly, the heightened section 123 is located between the adjacent arch sections 121 and the connection section 122, and one side of the heightened section 123 close to the support portion 111 is connected with the arch section 121, and the other side is connected with the connection section 122, so that the whole bump foil 120 is connected into a whole. Like the top foil 110, the arch section 121, the elevated section 123 and the connecting section 122 are integrally formed.

The bump foil 120 is disposed around the support portion 111 as a whole. Both ends of the bump foil 120 are adjacent to the fixing portion 112, respectively, in the circumferential direction of the foil dynamic pressure bearing 100. The side of the bump foil 120 facing away from the support portion 111 is fitted into the viscoelastic cylinder 130, that is, the side of the elevated portion 123 facing away from the support portion 111 and the connecting portion 122 are both fitted into the viscoelastic cylinder 130 and fixedly connected to the viscoelastic cylinder 130.

Due to the presence of the raised section 123, the wave height of the wave foil 120 is greatly increased. Even if the viscoelastic cylinder 130 is fitted on the side of the corrugated foil 120 facing away from the support portion 111, the corrugated foil 120 still has a sufficient effective wave height. When the rotor-bearing system vibrates, the rotation shaft 300 applies pressure to the bump foil 120 through the support portion 111, and the bump foil 120 can be smoothly deformed after being pressed.

Specifically, the viscoelastic cylinder 130 is composed of a first filling portion 131, a second filling portion 132, a coupling portion 133, and an axial positioning projection 134, and the first filling portion 131, the second filling portion 132, the coupling portion 133, and the axial positioning projection 134 are integrally molded.

The first filling part 131 is provided in plurality, and the first filling part 131 is provided along the axial direction of the foil dynamic pressure bearing 100. Each first filling portion 131 corresponds to each arch segment 121, and the first filling portion 131 is located between the two heightening segments 123 connected to the corresponding arch segment 121 and is located on a side of the corresponding arch segment 121 facing away from the supporting portion 111.

The first filling portion 131 is not in direct contact with the arcuate section 121, and a first cooling channel 135 is formed therebetween, so as to facilitate air flow circulation and heat dissipation of the foil dynamic pressure bearing 100.

The second filling portion 132 is provided in plurality, and the second filling portion 132 is provided along the axial direction of the foil dynamic pressure bearing 100. Each second filling portion 132 corresponds to each connecting section 122, and the second filling portion 132 is located between the two raised sections 123 connected to the corresponding connecting section 122 and on the side of the corresponding connecting section 122 facing the support portion 111.

The second filling portion 132 is in direct contact with the connecting section 122, and a second cooling channel 136 is formed between the second filling portion 132 and the supporting portion 111 to improve the heat dissipation capability of the foil dynamic pressure bearing 100.

The two coupling portions 133 are provided, one of the coupling portions 133 is located at one end of each of the first filling portion 131 and the second filling portion 132 in the axial direction of the foil hydrodynamic bearing 100, and the other coupling portion 133 is located at the other end of each of the first filling portion 131 and the second filling portion 132 in the axial direction of the foil hydrodynamic bearing 100. Both the connecting portions 133 are simultaneously connected to each of the first filling portion 131 and the second filling portion 132, thereby integrally connecting the first filling portion 131 and the second filling portion 132 separated by the elevated portion 123.

The axial positioning protrusions 134 are disposed in pairs, and the two axial positioning protrusions 134 are respectively located at two ends of the first filling portion 131 along the length direction and connected to one side of the first filling portion 131 facing away from the arch segment 121.

When the foil hydrodynamic bearing 100 is used, the foil hydrodynamic bearing 100 is mounted on the bearing seat 200, and the axial positioning protrusion 134 is embedded in the groove on the inner wall of the bearing seat 200, so that the foil hydrodynamic bearing 100 and the bearing seat 200 are relatively fixed in the axial direction.

The above-mentioned structures constituting the viscoelastic cylinder 130 are connected as a whole, and the bump foil 120 is embedded in the viscoelastic cylinder 130 and tightly connected to the viscoelastic cylinder 130. The viscoelastic cylinder 130 does not need to be positioned in the circumferential direction and the axial direction in other ways, so that the foil dynamic pressure bearing 100 can keep the first cooling channel 135 and the second cooling channel 136, and the cooling gas can timely take away the heat generated by the foil dynamic pressure bearing 100 without generating the problem of overheating of the bearing.

Further, the side of the first filling portion 131 facing away from the supporting portion 111 is aligned with the side of the connecting segment 122 facing away from the supporting portion 111, and both sides are located on the same cylindrical surface.

When the foil dynamic pressure bearing 100 is mounted on the bearing housing 200, the side of the connecting section 122 facing away from the support 111 forms a clearance fit with the inner wall of the bearing housing 200. Compared with the viscoelastic cylinder 130, the bump foil 120 and the top foil 110 made of metal or alloy are more stable and will not deform due to aging of the materials during long-term use. Therefore, the bump foil 120 is directly contacted with the inner wall of the bearing housing 200 by the pressure of the air film inside the foil hydrodynamic bearing 100, and the gap between the foil hydrodynamic bearing 100 and the rotating shaft 300 is controlled by the bump foil 120 and the top foil 110, so that the uniformity of the gap can be ensured, and the performance of the foil hydrodynamic bearing 100 can be maintained for a long time.

In another embodiment of this embodiment, the viscoelastic sleeve 130 may also completely enclose the connecting segment 122.

Further, the axial positioning protrusions 134 are formed around the outer periphery of the bump foil 120, are arranged along the circumferential direction of the foil dynamic pressure bearing 100, and are simultaneously connected to the respective first filling portions 131.

The respective first filling portions 131 are connected by the axial positioning projections 134, so that the viscoelastic cylinder 130 has a stronger integrity. The axial positioning protrusion 134 constricts the bump foil 120, so that the connection between the bump foil 120 and the viscoelastic cylinder 130 is tighter, thereby enhancing the stability of the foil dynamic pressure bearing 100.

In addition, the axial locating projection 134 can also function as an O-ring 600. According to the experience of using the static pressure gas bearing, the axial positioning protrusion 134 arranged along the circumferential direction of the foil dynamic pressure bearing 100 is tightly matched with the inner wall groove of the bearing seat 200, and the side of the connecting section 122 of the foil dynamic pressure bearing 100, which is opposite to the supporting part 111, and each first filling part 131 are in clearance fit with the inner wall of the bearing seat 200, so that a sealed cavity is formed together. Under the action of external force, the foil dynamic pressure bearing 100 extrudes air in the sealed cavity, so that a throttling energy consumption effect similar to that of an air spring can be generated, the instability threshold of half-frequency vortex motion of the rotor-bearing system is improved, the vibration of the rotor-bearing system at the working rotating speed is reduced, equipment can run at a higher rotating speed, the equipment can run more efficiently and quietly, and the stability of the rotor-bearing system is improved. The customized O-ring 600 does not need to be purchased additionally, so that the manufacturing cost is reduced, and the installation process is simplified.

In another specific embodiment of this embodiment, the first filling portion 131 may be in contact with the arch segment 121, and the second filling portion 132 may be in contact with the support portion 111. At this time, the viscoelastic cylinder 130 wraps the entire bump foil 120.

In another embodiment of this embodiment, the lengths of the first filling portion 131 and the second filling portion 132 may be smaller than the length of the bump foil 120 in the axial direction of the foil dynamic pressure bearing 100. At this time, the viscoelastic cylinder 130 wraps only a part of the bump foil 120 in the axial direction of the foil dynamic pressure bearing 100.

In another specific embodiment of this embodiment, the sum of the numbers of the first filling parts 131 and the second filling parts 132 may be smaller than the number of the heightening sections 123. At this time, the viscoelastic cylinder 130 wraps only a portion of the bump foil 120 in the circumferential direction of the foil dynamic pressure bearing 100.

In another specific embodiment of the present embodiment, only the bump foil 120 may be embedded in the viscoelastic cylinder 130, the bump foil 120 may be fixed by the viscoelastic cylinder 130, and the top foil 110 may be indirectly fixed to the viscoelastic cylinder 130 through the bump foil 120.

In another specific embodiment of the present embodiment, the viscoelastic cylinder 130 may be composed of only the first filling part 131, the second filling part 132, and the coupling part 133.

In another specific implementation manner of this embodiment, the axial positioning protrusions 134 may also be provided in other shapes, and the number of the axial positioning protrusions 134 may also be adjusted, such as one, three, etc.

In another embodiment of this embodiment, the outer sidewall of the viscoelastic cylinder 130 may also be designed to facilitate the formation of the throttling damping energy consumption of the air spring.

In short, the foil dynamic pressure bearing 100 directly fixes the top foil 110 and the bump foil 120 by the viscoelastic cylinder 130, instead of welding or fastening the top foil 110 and the bump foil 120 by the bearing sleeve 530. The relative position relationship between the top foil 110, the wave foil 120 and the viscoelastic cylinder 130 is stable, the top foil 110 or the wave foil 120 cannot be pulled out of the viscoelastic cylinder 130, and the viscoelastic cylinder 130 functions as the bearing sleeve 530. Therefore, the bearing sleeve 530 may be removed, and the above-described foil hydrodynamic bearing 100 may be directly installed in the bearing housing 200 of the apparatus, thereby shortening a dimensional chain, improving the centering accuracy of the foil hydrodynamic bearing 100, and simultaneously saving the processing cost of the bearing sleeve 530, greatly reducing the processing cost of the foil hydrodynamic bearing 100, and simplifying the structure of the foil hydrodynamic bearing 100.

Similarly, when the takeoff rotation speed performance test is performed on the foil dynamic pressure bearing 100, the bearing sleeve 530 is not needed, and the foil dynamic pressure bearing 100 can be directly installed on a test bench to directly evaluate the installation quality.

The bump foil 120 and the viscoelastic cylinder 130 are fitted to each other and tightly connected to each other. With the elastic deformation of the bump foil 120, the viscoelastic cylinder 130 connected thereto can be compressed by the deformation of the bump foil 120 and also stretched by the deformation of the bump foil 120. Therefore, the hysteresis characteristic of the viscoelastic cylinder 130 can be fully utilized, the area enveloped by the hysteresis curve is larger, and the damping effect is stronger, so that the mechanical energy generated when the rotor-bearing system vibrates can be quickly consumed, the vibration of the rotor-bearing system is effectively inhibited, and the stability of the rotor-bearing system is improved.

Referring to fig. 8 and 9, the present embodiment further provides a shaft assembly including a shaft 300, a bearing housing 200 and the foil hydrodynamic bearing 100. Wherein the rotating shaft 300 passes through the foil dynamic pressure bearing 100. The viscoelastic cylinder 130 in the foil dynamic pressure bearing 100 is mounted on the bearing seat 200, and the axial positioning protrusion 134 arranged along the circumferential direction of the foil dynamic pressure bearing 100 is tightly fitted with the inner wall groove of the bearing seat 200, and the side of the connecting section 122 of the foil dynamic pressure bearing 100 facing away from the supporting part 111 and each first filling part 131 are in clearance fit with the inner wall of the bearing seat 200, and an air gap 210 is present, so as to form a sealed chamber together.

Example 3

Referring to fig. 10, the present embodiment provides a casting mold 400 for processing the above-mentioned foil dynamic pressure bearing 100, wherein the casting mold 400 includes a mold body 410 and a positioning member 420.

Specifically, the mold body 410 is provided with a cavity for accommodating the top foil 110 and the bump foil 120. The cavity is generally cylindrical and has a length greater than the length of the top foil 110 and the bump foil 120. When the top foil 110 and the bump foil 120 are placed in the cavity, the side of the connecting section 122 facing away from the support 111 abuts against the inner side wall of the cavity. In addition, an annular groove is formed in the inner side wall of the cavity and used for forming the axial positioning protrusion 134.

Referring to fig. 11, specifically, the positioning member 420 is cylindrical, and one end of the positioning member 420 along the axial direction is provided with a plurality of avoiding grooves, and the plurality of avoiding grooves are respectively engaged with the heightening sections 123 and the fixing portion 112.

In addition, the length of the avoiding groove is equal to the length of the top foil 110 and the bump foil 120, so that the length of the positioning member 420 is less than the length of the cavity. The difference between the lengths of the avoiding groove and the positioning member 420 is equal to the length of one of the coupling portions 133 in the axial direction of the foil hydrodynamic bearing 100, and the difference between the lengths of the positioning member 420 and the cavity is equal to the length of the other coupling portion 133 in the axial direction of the foil hydrodynamic bearing 100. A bump is formed on the bottom surface of the inner wall of the cavity and abuts against one end of the positioning member 420, which is provided with the avoiding groove.

In another embodiment of this embodiment, the length of the avoiding groove may be greater than the lengths of the top foil 110 and the bump foil 120, and the length of the positioning member 420 may be equal to the length of the cavity. The difference between the lengths of the avoiding groove and the top foil 110 is equal to the length of one of the coupling portions 133 in the axial direction of the foil hydrodynamic bearing 100, and the difference between the lengths of the positioning member 420 and the avoiding groove is equal to the length of the other coupling portion 133 in the axial direction of the foil hydrodynamic bearing 100. The bottom surface of the inner wall of the cavity is also provided with a convex block which is clamped with the notch of the avoiding groove to completely seal the avoiding groove.

When the viscoelastic cylinder 130 is cast, the top foil 110 and the wave foil 120 are aligned, the positioning member 420 is inserted into the top foil 110 and the wave foil 120, and the positioning member 420, the top foil 110, and the wave foil 120 are placed in the cavity. At this time, the inner wall of the cavity and the outer wall of the positioning member 420 form a casting cavity, and the connecting section 122, the partially raised section 123 and the partially fixing portion 112 are all located in the casting cavity. After the viscoelastic material in a molten state is introduced into the casting cavity and is sufficiently cooled to form the viscoelastic cylinder 130, the connecting section 122, part of the raised section 123 and part of the fixing portion 112 are wrapped by the viscoelastic cylinder 130.

Wherein, the side of the connecting section 122 back to the supporting part 111 is attached to the inner side wall of the cavity without adhesive elastic material. The connection section 122 forms an outer circumferential surface of the foil dynamic pressure bearing 100 together with the first filling part 131.

In all examples shown and described herein, any particular value should be construed as merely exemplary, and not as a limitation, and thus other examples of example embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

The above examples are merely illustrative of several embodiments of the present invention, and the description thereof is more specific and detailed, but not to be construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention.