Power equipment

Abstract

The present disclosure provides a power device, including a rotor and a shaft support assembly for supporting the rotor, the shaft support assembly including: a bearing support having a bearing mounting hole; a hydrodynamic gas bearing, the hydrodynamic gas bearing being mounted in the bearing mounting hole, including a bearing housing and a foil assembly disposed in the bearing housing, the foil assembly forming an axial hole of the hydrodynamic gas bearing, the rotor being rotatably mounted in the axial hole; a bearing wear detection device including a pressure sensor, the pressure sensor being configured to detect the air film pressure of the bearing gap between the rotor and the foil assembly to determine the wear state of the hydrodynamic gas bearing according to the air film pressure. The technical solution of the present disclosure is conducive to convenient and low-cost real-time monitoring of the system stability of the power device.

Description

Technical Field

[0001] The present disclosure relates to the technical field of bearings, and in particular to a power device. Background Art

[0002] With the advantages of oil-free, high speed and high temperature resistance, gas bearings have developed rapidly since the 1960s and have a very broad application prospect in power equipment such as high-speed turbines and compressors.

[0003] According to the different mechanisms of lubricating gas film generation, gas bearings are divided into static pressure gas bearings and dynamic pressure gas bearings.

[0004] Static pressure gas bearings use an external gas source to supply air to the bearing to generate pressure to support the load, while dynamic pressure gas bearings use the pressure gas film generated by the wedge-shaped gap between the rotor and the inner surface of the dynamic pressure gas bearing to support the load.

[0005] The working principle of hydrodynamic gas bearings is as follows Figure 1 and Figure 2 shown. Figure 1 It is a schematic diagram of the local structure of the dynamic pressure gas bearing and the rotor when they are matched in the related technology. Figure 2 for Figure 1 The schematic diagram of the principle of generating a dynamic pressure gas film when the dynamic pressure gas bearing and the rotor cooperate is shown. When the rotor 1' is running at high speed, due to the force on the rotor 1', such as gravity, the center of the rotor 1' is eccentric with the center of the dynamic pressure gas bearing 2', and a wedge-shaped bearing gap is formed between the inner surface of the dynamic pressure gas bearing 2' and the rotor 1'. When the rotor 1' is rotating at high speed, due to the viscosity of the gas, gas with a certain viscosity is continuously brought into the wedge-shaped gap, and the continuous entry of the gas causes the gas film to generate a certain pressure. When the gas film pressure is sufficient to balance the load of the rotor 1', the rotor 1' is completely separated from the dynamic pressure gas bearing 2', forming a dynamic pressure gas film 3' to support the operation of the rotor 1'.

[0006] From the above principle, it can be known that the hydrodynamic gas bearing is actually a kind of sliding bearing, and the key to its operation is to form a hydrodynamic gas film with sufficient supporting force. In other words, when the speed is low, such as during startup and shutdown, a hydrodynamic gas film cannot be formed. At this time, dry friction occurs between the shaft and the bearing, and the bearing wears. Therefore, frequent starting and stopping will affect the life of the bearing, and in severe cases, it will cause bearing failure. In addition, other factors may also lead to the possibility of bearing failure, such as rotor resonance, excessive imbalance, shaft deformation, etc. Once the bearing fails, the machine will not work, and even accidents may occur in severe cases. Therefore, real-time testing of the operating reliability of the bearing is of great significance to ensure the smooth operation of the rotor and prevent failure accidents in advance.

[0007] The most direct way to test the operating reliability of bearings is to use displacement sensors to monitor the amplitude of the rotor in real time, and judge whether it is operating normally according to the amplitude of the rotor. However, the displacement sensors of this solution are relatively expensive, and more expensive collectors and displays are required. Therefore, it is of great significance to study a convenient and low-cost dynamic pressure gas bearing wear detection technology to improve product reliability. Summary of the invention

[0008] The present disclosure provides a power device, comprising a rotor and a shaft support assembly for supporting the rotor, wherein the shaft support assembly comprises:

[0009] A bearing support having a bearing mounting hole;

[0010] a dynamic pressure gas bearing, the dynamic pressure gas bearing being mounted in the bearing mounting hole, comprising a bearing housing and a foil assembly disposed in the bearing housing, the foil assembly forming an axial hole of the dynamic pressure gas bearing, the rotor being rotatably mounted in the axial hole; and

[0011] The bearing wear detection device comprises a pressure sensor, wherein the pressure sensor is configured to detect the air film pressure of the bearing gap between the rotor and the foil assembly to determine the wear state of the dynamic pressure gas bearing according to the air film pressure.

[0012] In some embodiments, the bearing housing has a pressure measuring hole communicating with the radial inner circumference and the radial outer circumference thereof, and the sensor air inlet of the pressure sensor is communicated with the bearing gap through the pressure measuring hole.

[0013] In some embodiments, an air storage cavity is provided between the hole wall of the bearing mounting hole and the outer peripheral surface of the bearing housing of the dynamic pressure gas bearing, and the pressure measuring hole is communicated with the air storage cavity;

[0014] The sensor air inlet is communicated with the air storage cavity.

[0015] In some embodiments, the bearing housing has a plurality of pressure measuring holes connected to the same air storage cavity.

[0016] In some embodiments, a plurality of gas storage cavities are axially arranged between the hole wall of the bearing mounting hole and the outer peripheral surface of the bearing housing of the dynamic pressure gas bearing, and each of the gas storage cavities is respectively connected to a plurality of pressure measuring holes arranged axially along the dynamic pressure gas bearing;

[0017] The bearing wear detection device includes a plurality of pressure sensors, and the plurality of pressure sensors are respectively connected to the plurality of air storage chambers.

[0018] In some embodiments, the bearing wear detection device includes a plurality of the pressure sensors, and the plurality of the pressure sensors are configured to detect the gas film pressure of the bearing gap at different positions along the axial direction of the hydrodynamic gas bearing.

[0019] In some embodiments, the bearing housing has a bearing air inlet hole located in the axial middle of the bearing housing, and the plurality of pressure sensors are distributed on both axial sides of the bearing air inlet hole.

[0020] In some embodiments, the bearing housing has a bearing air inlet hole located in the axial middle part of the bearing housing, and the power equipment also includes a plurality of sealing rings, which are located between the bearing support and the bearing housing and are respectively arranged on both sides of the bearing air inlet hole along the axial direction of the hydrodynamic gas bearing.

[0021] In some embodiments, the bearing housing has a bearing air inlet hole located in the axial middle part of the bearing housing, and the power equipment also includes two comb tooth sealing components arranged at the axial ends of the bearing housing, the comb tooth sealing component has a shaft sealing hole, and the hole wall of the shaft sealing hole is provided with sealing comb teeth, and the end face of the comb tooth sealing component close to the dynamic pressure gas bearing abuts against the corresponding end face of the dynamic pressure gas bearing, the rotor is installed in the shaft sealing hole, and the outer peripheral surface of the rotor cooperates with the sealing comb teeth.

[0022] In some embodiments, the portion where the rotor cooperates with the comb tooth sealing component includes a step surface, and the sealing comb teeth include a first-step tooth that cooperates with the end face of the step surface close to the hydrodynamic gas bearing and a second-step tooth located on the side of the first-step tooth away from the hydrodynamic gas bearing.

[0023] In some embodiments, a plurality of the shaft support assemblies are arranged along the axial direction of the rotor.

[0024] In some embodiments, the power plant includes a compressor.

[0025] Based on the power equipment provided by the present invention, a bearing wear detection device is set up. By utilizing the positive correlation between the rotational speed of the rotor and the air film pressure, the air film pressure in the bearing gap between the rotor and the foil assembly is detected by a pressure sensor to judge the wear state of the dynamic pressure gas bearing based on the air film pressure, which is conducive to convenient and low-cost real-time monitoring of the system stability of the power equipment.

[0026] Other features and advantages of the present disclosure will become apparent from the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings described herein are used to provide a further understanding of the present disclosure and constitute a part of the present application. The illustrative embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation on the present disclosure. In the drawings:

[0028] Figure 1 It is a schematic diagram of the local structure of the dynamic pressure gas bearing and the rotor when they are matched in the related technology.

[0029] Figure 2 for Figure 1 The schematic diagram of the principle of generating a dynamic pressure gas film when the dynamic pressure gas bearing and the rotor are combined is shown.

[0030] Figure 3 It is a schematic diagram of a partial cross-sectional structure of a power device according to an embodiment of the present disclosure.

[0031] Figure 4 for Figure 3 Schematic diagram of the enlarged structure of part I.

[0032] Figure 5 for Figure 3 The three-dimensional structural schematic diagram of the bearing housing of the hydrodynamic gas bearing in the power equipment is shown.

[0033] Figure 6 for Figure 5 The cross-sectional structural schematic diagram of the bearing housing is shown. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present disclosure and its application or use. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present disclosure.

[0035] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present disclosure. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0036] In the description of the present disclosure, it should be understood that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present disclosure.

[0037] In the description of the present disclosure, it should be understood that the directional words are only for the convenience of describing the present disclosure and simplifying the description. Unless otherwise stated, these directional words do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present disclosure; the directional words "inside and outside" refer to the inside and outside relative to the contour of each component itself.

[0038] like Figures 3 to 6 As shown, an embodiment of the present disclosure provides a power device. The power device includes a rotor 2 and a shaft support assembly for supporting the rotor 2. The power device is, for example, a compressor.

[0039] like Figures 3 to 6 As shown, the shaft support assembly includes a bearing support 5, a dynamic pressure gas bearing 7 and a bearing wear detection device. The bearing support 5 has a bearing mounting hole. The dynamic pressure gas bearing 7 is installed in the bearing mounting hole of the bearing support 5. The dynamic pressure gas bearing 7 includes a bearing housing 71 and a foil assembly 72 arranged in the bearing housing 71. The foil assembly 72 forms an axial hole of the dynamic pressure gas bearing 7. The rotor 2 is rotatably mounted in the axial hole of the dynamic pressure gas bearing 7. The bearing wear detection device includes a pressure sensor 6. The pressure sensor 6 is configured to detect the air film pressure in the bearing gap between the rotor 2 and the foil assembly 72 to determine the wear state of the dynamic pressure gas bearing 7 according to the air film pressure.

[0040] According to the characteristics of the hydrodynamic gas bearing, the faster the rotor speed, the greater the air film pressure between the rotor and the hydrodynamic gas bearing, and the greater the supporting force that can be provided. Therefore, the rotor speed and the air film pressure of the hydrodynamic gas film are positively correlated. For a hydrodynamic gas bearing and rotor with certain structural parameters, the rotor speed and the air film pressure should have a certain relationship. When the hydrodynamic gas bearing wears, the air film pressure formed will deviate from the original value. In the power equipment of the disclosed embodiment, a bearing wear detection device is provided. By utilizing the positive correlation between the speed of the rotor 2 and the air film pressure, the pressure sensor 6 is used to detect the air film pressure in the bearing gap between the rotor 2 and the foil assembly 72 to judge the wear state of the hydrodynamic gas bearing 7 according to the air film pressure, which is conducive to convenient and low-cost real-time monitoring of the system stability of the power equipment.

[0041] like Figures 3 to 6 As shown, in some embodiments of the power equipment, the bearing housing 71 has a pressure measuring hole 711 connecting its radial inner circumference and radial outer circumference, and the sensor air inlet of the pressure sensor 6 is connected to the bearing gap through the pressure measuring hole 711.

[0042] like Figures 3 to 6 As shown, in some embodiments of the power equipment, an air storage chamber 51 is provided between the hole wall of the bearing mounting hole and the outer peripheral surface of the bearing housing 71 of the dynamic pressure gas bearing 7. The pressure measuring hole 711 is connected to the air storage chamber 51; and the sensor air inlet of the pressure sensor 6 is connected to the air storage chamber 51.

[0043] The air inlet of the pressure sensor 6 is connected to the pressure measuring hole 711 through the air storage cavity 51, which is beneficial to maintaining the stability of the air film pressure measured by the pressure sensor 6 and reducing the fluctuation of the measured air film pressure.

[0044] like Figures 3 to 6 As shown, in some embodiments of the power equipment, the bearing housing 71 has a plurality of pressure measuring holes 711 connected to the same air storage cavity 51. One air storage cavity 51 is connected to a plurality of pressure measuring holes 711, which is conducive to integrating the pressure of each pressure measuring hole 711, thereby facilitating more accurate measurement of the air film pressure at the corresponding position.

[0045] In some embodiments of the power equipment, the bearing wear detection device includes a plurality of pressure sensors 6, and the plurality of pressure sensors 6 detect the gas film pressure of the aforementioned bearing gap at different positions along the axial direction of the hydrodynamic gas bearing 7.

[0046] like Figures 3 to 6As shown, in some embodiments of the power equipment, a plurality of air storage chambers 51 are axially arranged between the hole wall of the bearing mounting hole and the outer peripheral surface of the bearing housing 71 of the dynamic pressure gas bearing 7. Each air storage chamber 51 is respectively connected to a plurality of pressure measuring holes 711 arranged along the axial direction of the dynamic pressure gas bearing 7. The bearing wear detection device includes a plurality of pressure sensors 6, and the plurality of pressure sensors 6 are respectively connected to the plurality of air storage chambers 51.

[0047] The use of multiple pressure sensors can realize multi-segment detection of the air film pressure of the hydrodynamic gas bearing 7 along the axial direction, which is conducive to more effective real-time monitoring of the stability of the power equipment.

[0048] like Figures 3 to 6 As shown, in some embodiments of the power equipment, the bearing housing 71 has a bearing air inlet 712 located in the axial middle of the bearing housing 71, and a plurality of pressure sensors 6 are distributed on both axial sides of the bearing air inlet 712. Using multiple pressure sensors 6 to detect whether the dynamic pressure gas bearing 7 is worn is conducive to integrating multiple pressure data and avoiding the situation where a single pressure sensor 6 is disturbed and displays abnormality.

[0049] like Figures 3 to 6 As shown, in some embodiments of the power equipment, the bearing housing 71 has a bearing air inlet hole 712 located in the axial middle part of the bearing housing 71, and the power equipment also includes a sealing device, the sealing device includes a plurality of sealing rings 8, the plurality of sealing rings 8 are located between the bearing support 5 and the bearing housing 71 of the hydrodynamic gas bearing 7 and are respectively arranged on both sides of the bearing air inlet hole 712 along the axial direction of the hydrodynamic gas bearing 7.

[0050] The sealing ring 8 is used to seal the fitting gap between the bearing support 5 and the bearing housing 71 of the hydrodynamic gas bearing 7, which helps to avoid leakage of gas in the bearing gap and improve the stability of the gas film pressure. At the same time, the sealing ring 8 can provide additional damping for the hydrodynamic gas bearing 7.

[0051] like Figures 3 to 6 As shown, in some embodiments of the power equipment, the bearing housing 71 has a bearing air inlet hole 712 located in the axial middle of the bearing housing 71. The power equipment also includes two comb-tooth sealing components arranged at both ends of the bearing housing 71 in the axial direction. The comb-tooth sealing component has a shaft seal hole, and the hole wall of the shaft seal hole is provided with sealing comb teeth. The end face of the comb-tooth sealing component close to the dynamic pressure gas bearing 7 is abutted against the corresponding end face of the dynamic pressure gas bearing 7, and the rotor 2 is installed in the shaft seal hole, and the outer peripheral surface of the rotor 2 is matched with the sealing comb teeth.

[0052] Comb-teeth sealing components are respectively arranged at the axial ends of the bearing housing 71 , which is beneficial to reducing the sudden change of the air flow pressure at the gas outlet of the hydrodynamic gas bearing 7 , thereby improving the stability of the air film distribution and pressure detection of the hydrodynamic gas bearing 7 .

[0053] like Figures 3 to 6 As shown, in some embodiments of the power equipment, the portion where the rotor 2 cooperates with the comb-tooth sealing component includes a step surface, and the sealing comb teeth of the comb-tooth sealing component include a first-step tooth that cooperates with the end face of the step surface close to the hydrodynamic gas bearing 7 and a second-step tooth located on the side of the first-step tooth away from the hydrodynamic gas bearing 7.

[0054] The part where the rotor 2 cooperates with the comb-tooth sealing component is provided with a step surface, and the comb-tooth sealing component is provided with first-order teeth and second-order teeth correspondingly, which is beneficial to reducing the sudden change of the outlet air flow pressure, and further beneficial to improving the stability of the air film distribution and pressure detection of the dynamic pressure gas bearing 7.

[0055] In some embodiments of the power equipment, a plurality of shaft support assemblies are arranged along the axial direction of the rotor 2. Figure 3 As shown, in the embodiment of the present disclosure, a shaft support assembly is arranged at each of the two axial ends of the rotor 2. This arrangement is conducive to making the dynamic pressure gas bearings 7 on both sides bear force evenly, which is convenient for pressure detection.

[0056] Combine the following Figures 3 to 6 A specific embodiment of the present disclosure is further described.

[0057] like Figures 3 to 6 As shown, the power device of the disclosed embodiment includes a power device housing 1, a rotor 2, a motor stator 3 and two shaft support assemblies. The two shaft support assemblies are respectively supported between the power device housing 1 and the rotor 2 and are respectively located at the left and right ends of the rotor 2 to support the rotor 2 on the power device housing 1.

[0058] The power equipment housing 1 is an irregular cavity part, generally cast, and plays a supporting and protecting role for the core components of the power equipment.

[0059] The motor stator 3 is fixedly installed inside the power equipment housing 1, and the motor stator 3 has a rotor mounting hole. The rotor 2 is rotatably installed in the rotor mounting hole of the motor stator 3. The rotor 2 is a shaft-like, solid part, and forms a motor with the motor stator 3. When working, the rotor 2 performs high-speed rotation under the action of the electromagnetic field.

[0060] In order to explain the shaft support assembly of the disclosed embodiment in detail, the present embodiment is explained below by taking the shaft support assembly located at the left end of the rotor 2 as an example. The composition of the shaft support assembly located at the right end of the rotor 2, the structure and function of each component, etc. can all refer to the corresponding contents describing the shaft support assembly located at the left end of the rotor 2.

[0061] like Figures 3 to 6 As shown, the shaft support assembly includes a first comb teeth seal 4, a bearing support 5, a pressure sensor 6, a dynamic pressure gas bearing 7, a sealing ring 8 and a second comb teeth seal 9.

[0062] The dynamic pressure gas bearing 7 is installed in the bearing mounting hole of the bearing support 5. The dynamic pressure gas bearing 7 includes a bearing housing 71 and a foil assembly 72. The bearing housing 71 of the bearing support 5 is a rotating hollow part. Figure 4 As shown, in this embodiment, the foil assembly 72 includes a support foil 721 located radially inside the bearing housing 71 and a top foil 722 located radially inside the support foil 721. The inner wall of the top foil 722 forms the shaft hole of the dynamic pressure gas bearing 7. The rotor 2 is installed in the shaft hole. A bearing gap is formed between the hole wall of the shaft hole and the rotor 2.

[0063] The form of the foil assembly 72 is not limited thereto. For example, in some embodiments not shown in the figures, it may include two layers of supporting foils 721 .

[0064] The bearing support 5 connects the power equipment housing 1 and the bearing housing 71 . A plurality of support air inlet holes 52 are evenly distributed along the circumferential direction on the bearing support 5 . The support air inlet holes 52 are passages for the gas outside the hydrodynamic gas bearing 7 to enter the hydrodynamic gas bearing 7 .

[0065] In order to prevent the airflow from impacting the pressure sensor 6 through the support air inlet hole 52, an annular groove is designed on the inner wall of the bearing mounting hole of the bearing support 5, and the annular groove cooperates with the outer peripheral surface of the bearing housing 71 to form an air storage cavity 51, and the air storage cavity 51 is connected to the pressure measuring hole 711 on the bearing housing 71, and the sensor air inlet of the pressure sensor 6 is connected to the air storage cavity 51. The air storage cavity 51 is used to buffer the gas entering the sensor air inlet.

[0066] The structure of the bearing housing 71 is as follows: Figure 5 and Figure 6 As shown. A plurality of pressure measuring holes 711 are evenly distributed along the circumferential direction on the bearing housing 71, and the pressure measuring holes 711 connect the bearing gap and the air storage chamber 51, so that the pressure sensor 6 can accurately test the pressure of the air film of the hydrodynamic gas bearing. As mentioned above, the rotation speed of the rotor 2 is positively correlated with the air film pressure of the bearing gap, that is, the greater the rotation speed, the greater the air film pressure. For a power device including the hydrodynamic gas bearing 7 and the rotor 2 with determined structural parameters, the rotation speed of the rotor has a definite relationship with the aforementioned air film pressure. When the hydrodynamic gas bearing is worn, the value detected by the pressure sensor 6 will deviate from the original value. Therefore, it is possible to judge whether the hydrodynamic gas bearing is worn based on the air film pressure detected by the pressure sensor 6.

[0067] like Figures 3 to 6 As shown, the middle portion of the bearing housing 71 has a plurality of bearing air inlet holes 712 evenly distributed along the circumferential direction, and the plurality of bearing air inlet holes 712 are correspondingly connected to the plurality of support air inlet holes 52 on the bearing support 5 .

[0068] In this embodiment, in order to achieve more accurate test results, in accordance with the structural characteristics that the bearing air inlet hole 712 divides the bearing housing 71 into two left and right parts, two pressure sensors 6 are symmetrically distributed about the bearing air inlet hole 712 to respectively test the dynamic pressure film pressure conditions on both sides of the axial direction of the bearing housing 71. In the disclosed embodiment, each shaft support assembly includes two pressure sensors 6.

[0069] Each shaft support assembly uses multiple pressure sensors 6 to detect whether the dynamic pressure gas bearing 7 is worn, which is conducive to integrating multiple pressure data and avoiding interference with a single pressure sensor 6, such as interference from the low-frequency filter of the frequency converter, which may cause abnormal display.

[0070] like Figure 3 and Figure 4 As shown, in order to prevent the leakage of the bearing air film pressure, the bearing support 5 and the bearing housing 71 adopt a clearance fit and a matching structure of a filling seal ring 8. The deformation and sealing effect of the seal ring 8 are conducive to preventing the air flow inside the dynamic pressure gas bearing 7 from leaking from the gap between the bearing support 5 and the bearing housing 71, which is conducive to improving the stability of the air film pressure and the accuracy of the pressure sensor 6 test. In addition, the deformation of the seal ring 8 also provides additional damping for the dynamic pressure gas bearing 7.

[0071] In the disclosed embodiment, four sealing grooves 713 are circumferentially arranged on the outer circumference of the bearing housing 7, and four sealing rings 8 are respectively installed in the four sealing grooves 713. Two sealing rings 8 are arranged on the left and right sides of the bearing air inlet hole 712, respectively.

[0072] In the disclosed embodiment, the first comb tooth seal 4 and the second comb tooth seal 9 are two comb tooth seal components respectively disposed at the left and right ends of the dynamic pressure gas bearing 7. The first comb tooth seal 4 and the second comb tooth seal 9 are both rotating parts, and are clearance-matched with the rotor 2, and the clearance with the rotor is the airflow outlet of the dynamic pressure gas bearing 7.

[0073] In order to reduce the pressure mutation of the outlet airflow of the hydrodynamic gas bearing and improve the stability of the air film distribution of the hydrodynamic gas bearing 7 and the accuracy of pressure detection, the airflow outlet of the hydrodynamic gas bearing 7 in the embodiment of the present disclosure adopts a multi-comb, stepped structure.

[0074] like Figure 3 and Figure 4As shown, the parts where the rotor 2 cooperates with the first comb tooth seal 4 and the second comb tooth seal 9 all include step surfaces. Corresponding to the step surfaces, the sealing comb teeth of the first comb tooth seal 4 include first-step teeth 41 and second-step teeth 42, and the sealing comb teeth of the second comb tooth seal 9 include first-step teeth 91 and second-step teeth 92. That is, the first-step teeth and second-step teeth of the first comb tooth seal 4 and the second comb tooth seal 9 that form a stepped type cooperate with the corresponding step surfaces of the rotor 2 to form a plurality of gaps. When the rotor 2 rotates, the airflow in the dynamic pressure gas bearing 7 flows toward the airflow outlet, and when it flows through each gap, it is approximately an ideal throttling process, and its pressure and temperature decrease, and its speed increases; and when it enters the cavity of the sealing comb teeth, due to the sudden increase in the flow area, the airflow forms a strong vortex, the pressure remains unchanged but the speed almost completely disappears, and the more gaps the airflow flows through, the better the air film pressure is maintained. The use of a stepped distribution of sealing comb teeth has a better throttling effect, further reduces the sudden change in the outlet airflow pressure, and is conducive to the stability of the air film pressure of the dynamic pressure gas bearing 7.

[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present disclosure rather than to limit it. Although the present disclosure has been described in detail with reference to the preferred embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present disclosure can still be modified or some technical features can be replaced by equivalents, which should all be included in the scope of the technical solution for protection requested by the present disclosure.

Claims

1. A power device, characterized in that: The invention comprises a rotor (2) and a shaft support assembly for supporting the rotor (2), wherein the shaft support assembly comprises: A bearing support (5) having a bearing mounting hole; a dynamic pressure gas bearing (7), the dynamic pressure gas bearing (7) being mounted in the bearing mounting hole, comprising a bearing housing (71) and a foil assembly (72) arranged in the bearing housing (71), the foil assembly (72) forming an axial hole of the dynamic pressure gas bearing (7), and the rotor (2) being rotatably mounted in the axial hole; and A bearing wear detection device comprises a pressure sensor (6), wherein the pressure sensor (6) is configured to detect the air film pressure of the bearing gap between the rotor (2) and the foil assembly (72) to determine the wear state of the dynamic pressure gas bearing (7) according to the air film pressure; The bearing housing (71) has a pressure measuring hole (711) communicating with its radial inner peripheral surface and radial outer peripheral surface, and the sensor air inlet of the pressure sensor (6) is communicated with the bearing gap through the pressure measuring hole (711); An air storage chamber (51) is provided between the hole wall of the bearing mounting hole and the outer peripheral surface of the bearing housing (71) of the dynamic pressure gas bearing (7), and the pressure measuring hole (711) is in communication with the air storage chamber (51); The sensor air inlet is communicated with the air storage chamber (51).

2. The power equipment according to claim 1, characterized in that: The bearing housing (71) has a plurality of pressure measuring holes (711) that are in communication with the same air storage chamber (51).

3. The power equipment according to claim 1, characterized in that: A plurality of air storage chambers (51) are axially arranged between the hole wall of the bearing mounting hole and the outer peripheral surface of the bearing housing (71) of the dynamic pressure gas bearing (7), and each of the air storage chambers (51) is respectively connected to a plurality of pressure measuring holes (711) arranged axially along the dynamic pressure gas bearing (7); The bearing wear detection device comprises a plurality of pressure sensors (6), and the plurality of pressure sensors (6) are respectively connected to the plurality of air storage chambers (51).

4. The power equipment according to claim 3, characterized in that: The bearing housing (71) has a bearing air inlet hole (712) located in the axial middle of the bearing housing (71), and the plurality of pressure sensors (6) are distributed on both axial sides of the bearing air inlet hole (712).

5. The power equipment according to any one of claims 1 to 4, characterized in that: The bearing housing (71) has a bearing air inlet hole (712) located in the axial middle of the bearing housing (71), and the power equipment also includes a plurality of sealing rings (8), the plurality of sealing rings (8) are located between the bearing support (5) and the bearing housing (71) and are respectively arranged on both sides of the bearing air inlet hole (712) along the axial direction of the hydrodynamic gas bearing (7).

6. The power equipment according to any one of claims 1 to 4, characterized in that: The bearing housing (71) has a bearing air inlet hole (712) located in the axial middle part of the bearing housing (71), and the power equipment also includes two comb-tooth sealing components arranged at the axial ends of the bearing housing (71), the comb-tooth sealing component has a shaft sealing hole, and the hole wall of the shaft sealing hole is provided with sealing comb teeth, and the end face of the comb-tooth sealing component close to the dynamic pressure gas bearing (7) abuts against the corresponding end face of the dynamic pressure gas bearing (7), and the rotor (2) is installed in the shaft sealing hole, and the outer peripheral surface of the rotor (2) cooperates with the sealing comb teeth.

7. The power device according to claim 6, characterized in that: The portion where the rotor (2) cooperates with the comb tooth sealing component includes a step surface, and the sealing comb teeth include a first-step tooth that cooperates with the end face of the step surface close to the dynamic pressure gas bearing (7) and a second-step tooth located on a side of the first-step tooth away from the dynamic pressure gas bearing (7).

8. The power equipment according to any one of claims 1 to 4, characterized in that: It comprises a plurality of shaft support assemblies arranged along the axial direction of the rotor (2).

9. The power equipment according to any one of claims 1 to 4, characterized in that: The power equipment includes a compressor.

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