Aerostatic bearing with self-sensing and self-driving capabilities and implementation method of aerostatic bearing

Abstract

The invention discloses a static pressure gas bearing with self-sensing and self-driving functions and an implementation method of the static pressure gas bearing, and provides an innovative technical scheme for machining an adjustable pressure equalizing cavity on the working surface of a bearing disc aiming at the technical problems that a traditional small-hole throttling bearing is easy to cause air hammer vibration and a traditional annular surface throttling bearing is relatively weak in bearing capacity. According to the bearing, the annular pressure equalizing cavity is machined in the working surface of the bearing disc, the equivalent effect of small hole throttling is achieved through the structural form of annular face throttling, the occurrence probability of air hammer vibration is remarkably reduced, and the bearing capacity of the bearing is effectively improved. Besides, a microprocessor and a micro sensing driving mechanism (such as an MEMS element or a PZT and other special materials) are integrated in the annular pressure equalizing cavity, and an intelligent control algorithm is combined, so that the bearing has a self-sensing and self-driving function, parameters such as acceleration, temperature and gas film pressure can be sensed in real time, and the performance of the bearing can be regulated and controlled in real time according to an external excitation signal. The working stability, the bearing capacity and the intelligent regulation and control level of the bearing are remarkably improved, and the bearing is suitable for various complex working conditions.

Description

Technical Field

[0001] This invention relates to the field of gas bearing technology, and in particular provides a hydrostatic gas bearing with self-sensing and self-driving capabilities and a method for implementing it. Background Technology

[0002] High-precision operation of bearings under complex conditions (such as high speed and high load) is a key technological aspect for the development of industries such as automotive, aerospace, and shipbuilding. Against the backdrop of industries accelerating their development towards higher precision, higher efficiency, and higher quality, the durability and precision of bearings have become crucial factors for cost reduction and efficiency improvement, thus placing demands on bearing manufacturing technology for high rigidity, high load capacity, and high durability.

[0003] Traditional bearings such as cylindrical roller bearings, needle roller bearings, and tapered roller bearings often face problems such as severe wear, short service life, and decreased precision after wear during long-term service, making it difficult to meet the requirements of high-precision manufacturing for product consistency, high precision, and low cost. Hydrostatic gas bearings, by introducing external compressed gas into the bearing clearance, form a stable high-pressure gas film between moving and non-moving parts, thus achieving contactless support and near-zero friction. They have been widely used in ultra-precision machining, metrology, and aerospace fields. Currently, they mainly include two types: porous throttling hydrostatic gas bearings and borehole throttling hydrostatic gas bearings. Porous hydrostatic gas bearings, due to the immaturity of porous material preparation, cannot guarantee the consistency of material properties. The manufacturing process of borehole throttling hydrostatic gas bearings is relatively mature, enabling customized and mass production according to requirements. Existing orifice-type throttling hydrostatic gas bearings are divided into two types according to the throttling method: orifice throttling and toroidal throttling. Among them, orifice throttling hydrostatic gas bearings can achieve extremely high load-bearing capacity and stiffness compared to toroidal throttling because the orifice outlet is designed with a uniform cavity. However, compared to toroidal throttling, they are more prone to air hammer vibration, which can cause bearing instability and reduced machining accuracy. Summary of the Invention

[0004] To address the problems of traditional small-hole throttling bearings being prone to air hammer vibration and having weak load-bearing capacity, this invention proposes a toroidal small-hole throttling hydrostatic gas bearing with self-sensing and self-driving capabilities and its implementation method. By changing the structure of the toroidal throttling device, air hammer vibration can be avoided while enabling the bearing to achieve high load-bearing capacity and high stiffness, and the bearing can also maintain self-sensing and self-driving capabilities during use.

[0005] To address the problems existing in the prior art, the core principles and processing steps of this invention are as follows:

[0006] (1) To address the technical contradiction between the high load-bearing capacity but poor stability (prone to air hammer vibration) of traditional small-hole throttling bearings and the low load-bearing capacity but high stability of traditional toroidal throttling bearings, a pressure equalization chamber is opened on the working surface of the bearing plate. This allows the throttling effect of small-hole throttling to be achieved under the toroidal throttling structure, enabling the bearing to maintain high load-bearing capacity and high stiffness. At the same time, relying on the structural characteristics of toroidal throttling, the probability of air hammer vibration is reduced. In addition, by integrating sensors (such as PZT thin films) and actuators (such as MEMS) in the pressure equalization chamber, the bearing can actively sense its own performance status during service and achieve real-time control of bearing performance by intelligently adjusting the pressure equalization chamber structure.

[0007] (2) The substrate material for the bearing plate can be selected from metal, plastic or semiconductor according to the specific application requirements; for pressure equalization cavities with different cross-sectional shapes (such as triangle, rectangle, semicircle, etc.), high-precision processing can be achieved on the substrate surface through high-precision milling, laser processing or chemical etching to ensure its geometric accuracy and functional requirements.

[0008] (3) High-precision processing is carried out on the working surface of the bearing and the working surface of the bearing plate using mechanical grinding, electrolytic polishing and ultrasonic polishing processes to achieve submicron-level shape accuracy (geometric error ≤ 0.3 μm) and nano-level surface roughness (Ra ≤ 0.01 μm). This ensures the surface quality of the working surface of the annular orifice throttling hydrostatic gas bearing and the working surface of the bearing plate, which helps to reduce the gas film thickness, thereby improving the bearing load and stiffness and further suppressing the occurrence of gas hammer vibration.

[0009] (4) Using controllable subtractive manufacturing processes such as laser ablation, precision machining, or electrolytic machining, high-precision machining of microchannel / micropore structures is performed on the non-working surface (back side or internal substrate) of the bearing disk to achieve embedded integration of the sensor and actuator preset circuits. Under the premise of ensuring the shape and position accuracy of the bearing working surface, a low-loss signal transmission path and an efficient power transmission channel are established, significantly improving the response accuracy and reliability of the electromechanical system. In addition, additive manufacturing technologies such as 3D printing can also be used to realize the machining of the equalizing cavity and the embedded integration of preset circuits to complete the fabrication of the bearing disk.

[0010] (5) By integrating micro-sensors (such as PZT sensors, thermal sensors or acceleration sensors) inside the equalizing chamber, the pressure change, temperature rise, vibration and other information in the air film area are monitored in real time. The collected signals are transmitted to the external data acquisition system or the internal actuator system using the preset sensor circuit, thus constructing a real-time closed-loop monitoring system for the bearing operating status.

[0011] (6) The embedded actuation system (such as MEMS or thermal device) inside the bearing disk can not only dynamically adjust the geometric dimensions and surface curvature of the pressure equalization cavity based on the closed-loop feedback control response micro-sensor signal to maintain the stability of the bearing gas film; at the same time, it can be controlled by the external excitation signal to cause the pressure equalization cavity structure to undergo active deformation, thereby changing the bearing stiffness, damping and other properties.

[0012] Compared with existing technologies, the advantages of this method are as follows:

[0013] 1. Compared with traditional small-hole throttling bearings, the present invention changes the position of the pressure equalization chamber from the bearing surface to the working surface of the bearing plate, which not only avoids the disadvantage of small-hole throttling that is prone to air hammer vibration, but also makes up for the deficiency of low bearing capacity of toroidal throttling.

[0014] 2. In traditional small-hole throttling bearings, the pressure equalization cavity is located on the bearing working surface, which has limited machining accuracy and is prone to secondary damage to the small hole structure used for air supply during machining. This invention moves the pressure equalization cavity to the working surface of the bearing plate, which not only reduces the machining difficulty of the pressure equalization cavity and improves the diversity of the pressure equalization cavity, but also improves the flow field when the pressure equalization cavity is on the working surface of the bearing plate without reducing the bearing capacity.

[0015] 3. Since the pressure equalization cavity is located on the working surface of the bearing plate, different types of materials can be used to process the bearing plate for different types of working conditions. At the same time, the processing method of the pressure equalization cavity can be selected according to different precision and different types of materials, so as to ensure that the invention can achieve its function under different working conditions.

[0016] 4. Traditional hydrostatic gas bearings monitor their operating status indirectly by using embedded or external sensors to collect flow field information. Neither method allows for direct observation of the flow field information of the gas film without damaging it. This invention addresses this by adding miniature sensors, such as pressure, temperature, and displacement sensors, to the equalizing chamber, or by installing special materials, such as semiconductors or piezoelectric ceramics, at the bottom of the equalizing chamber. Utilizing the inherent properties of these materials, the bearing can directly monitor the gas film's state during operation, achieving self-sensing capability.

[0017] 5. Traditional hydrostatic gas bearings, once manufactured, can only adjust the gas supply pressure to handle complex operating conditions. However, this adjustment method is not only severely delayed but also lacks control precision. This invention integrates MEMS or special materials within the equalizing chamber, relying on external control commands or real-time monitoring signals to adjust the structure of the equalizing chamber, such as its depth, width, and radius of curvature. This causes the equalizing chamber structure to undergo active deformation, enabling the bearing to dynamically adjust under complex operating conditions and achieve self-driving capability.

[0018] 6. For hydrostatic gas bearings of the same specification, different material selections and structural parameters of the bearing disc can be used to adapt to the complex and diverse actual working conditions such as heavy load and high speed, effectively improving the bearing's working condition adaptability and application scenario coverage. Attached Figure Description

[0019] Figure 1 This is an overall schematic diagram of a hydrostatic gas bearing with self-sensing and self-driving capability according to the present invention. (1) is the bearing plate cover, (2) is the bolt for connection, (3) is the connection hole on the bearing plate cover that connects to the bearing plate base, (4) is the microprocessor integrated inside the bearing plate, (5) is the circuit interface for connecting with the outside world, (6) is the annular pressure equalization cavity on the working surface of the bearing plate, (7) is the sensing mechanism integrated inside the bearing plate, (8) is the air inlet of the bearing, (9) is the bearing base, (10) is the driving mechanism integrated inside the bearing plate, (11) is the circuit for interconnecting the various integrated devices inside the bearing plate, (12) is the bearing plate base, and (13) is the cavity reserved for the microprocessor.

[0020] Figure 2 This is a cross-sectional view of the structure of a hydrostatic gas bearing with self-sensing and self-driving capability according to the present invention, wherein (1) is the bearing disk cover, (5) is the circuit interface for connecting with the outside world, (6) is the annular equalizing cavity on the working surface of the bearing disk, (7) is the sensing mechanism integrated inside the bearing disk, (8) is the air inlet of the bearing, (9) is the bearing base, (10) is the driving mechanism integrated inside the bearing disk, (11) is the circuit for interconnecting the various integrated devices inside the bearing disk, (12) is the bearing disk base, and (14) is the small hole inside the bearing base.

[0021] Figure 3 This is a top view of the bearing plate base of a hydrostatic gas bearing with self-sensing and self-driving capability according to the present invention, wherein (4) is a microprocessor integrated inside the bearing plate, (5) is a circuit interface for connecting with the outside world, (11) is a circuit for interconnecting the various integrated devices inside the bearing plate, (12) is the bearing plate base, and (15) is a threaded hole on the bearing plate base that connects to the bearing plate cover.

[0022] Figure 4 This is a bottom view of the bearing plate base of a hydrostatic gas bearing with self-sensing and self-driving capability according to the present invention, wherein (5) is a circuit interface for connecting with the outside world, (6) is an annular pressure equalization cavity on the working surface of the bearing plate, (11) is a circuit for realizing the interconnection between various integrated devices inside the bearing plate, and (12) is the bearing plate base.

[0023] Figure 5This is a cross-sectional view of the bearing disk cover of a hydrostatic gas bearing with self-sensing and self-driving capability according to the present invention, wherein (1) is the bearing disk cover, (3) is the connection hole on the bearing disk cover that connects to the bearing disk base, and (13) is the cavity reserved for the microprocessor.

[0024] Figure 6 The diagram shows a comparison of the working principles of the self-sensing and self-driving hydrostatic gas bearing of the present invention and a traditional bearing. Figure (6a) shows the cross-section of a traditional small-hole bearing; Figure (6b) shows the cross-section of a traditional toroidal bearing; Figure (6c) shows the cross-section of the novel toroidal small-hole throttling bearing; (16) is the throttling region; and (17) is the pressure equalization chamber. It can be seen that the pressure equalization chamber of the traditional small-hole bearing is located on the bearing surface. If the machining size is too large, it will affect the performance of the small hole and easily cause air hammer vibration. The throttling region of the traditional toroidal bearing is smaller than that of the traditional small-hole bearing, and there is no pressure equalization chamber, resulting in a decrease in load-bearing capacity. The novel toroidal small-hole throttling bearing of the present invention optimizes the pressure equalization chamber to the working surface of the bearing plate, so that the throttling region is still located at the small hole, and the machining of the pressure equalization chamber will not affect the small hole, so that the bearing has better performance.

[0025] Figure 7 This is a manufacturing process diagram of a hydrostatic gas bearing with self-sensing and self-driving capabilities according to the present invention. Figure (7a) shows the bearing base processing flow, completing the processing of the bearing base air supply channel and small holes; Figure (7b) shows the bearing plate processing flow, completing the processing of the annular pressure equalization cavity and internal circuit; Figure (7c) shows the sensing / driving device integration and microprocessor installation flow; and Figure (7d) shows the packaging flow of the bearing plate cover and bearing plate base.

[0026] Figure 8 This is a schematic diagram of the sensing and driving principle of a hydrostatic gas bearing with self-sensing and self-driving capability according to the present invention. Among them, (18) is the deformation of the internally integrated sensing device under high pressure, (19) is the adaptive deformation of the driving device according to the working conditions, (8a) is a schematic diagram of normal working state, (8b) is a schematic diagram of the deformation of the sensing mechanism under local high pressure, and (8c) is a schematic diagram of the deformation of the driving mechanism according to the corresponding working conditions after receiving the driving signal. Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to specific implementation methods. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Example 1: The hydrostatic gas bearing with self-sensing and self-driving capabilities shown in this example has a core structure consisting of a bearing housing, a bearing disk base, and a sensing and driving device and microprocessor integrated inside the bearing disk base. Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown. Among them, (1) is the bearing plate cover, which is obtained by CNC machining. The bearing plate cover and the bearing plate base are rigidly connected by threaded connection; (2) and (8) are circuits used to realize the interconnection between the integrated devices inside the bearing plate and the connection with the external excitation source. The preset structure can be processed by etching and laser drilling, and then the circuit is connected by ion implantation; (3) is an integrated PZT material, which is processed in the annular pressure equalization cavity of the bearing plate by LIGA technology. It is connected to the microprocessor (9) through the interconnection circuit to realize the detection of gas film pressure. At the same time, it can also make the annular pressure equalization cavity... The structure changes, thereby realizing the control of bearing performance; (4) is the air inlet of the annular small hole throttling static pressure gas bearing; (5) is the small hole on the bearing base, which is realized by laser drilling technology; (6) is the bearing disk base, which is obtained by CNC machining; (7) is the annular equalizing cavity, which can be obtained by laser grooving technology or etching technology; (9) is the microprocessor, which is obtained by integrated chip; (11) and (12) are the connection holes between the bearing disk cover and the bearing disk base, which are realized by machining, and the two are rigidly connected by studs; (13) is the cavity preset for the microprocessor, which is obtained by CNC machining.

[0029] Example 2: This example describes a manufacturing process for a hydrostatic gas bearing with self-sensing and self-driving capabilities, such as... Figure 7 As shown:

[0030] 1. Obtain the bearing base of the preset size through machining, and realize the air passage and small holes inside the bearing base according to the preset plan through laser drilling technology;

[0031] 2. Obtain the bearing disk substrate of the preset size through machining, and realize the processing of the annular pressure equalization cavity on the working surface of the bearing disk according to the preset scheme by laser grooving or chemical etching technology;

[0032] 3. Using chemical etching or laser processing technology, corresponding microgrooves are processed on the top and inside of the carrier disk for the preset circuit, and then the circuit is connected by ion implantation.

[0033] 4. Using LIGA technology, MEMS structures such as varistors or special materials such as PZT are integrated and installed inside the annular pressure equalization cavity of the bearing disk. Combined with microcircuits, information such as bearing pressure and temperature is collected to realize the self-sensing of bearing status.

[0034] 5. By utilizing integrated chip technology, a microprocessor is integrated inside the bearing disk, combined with microcircuits and intelligent control algorithms, to process the bearing's self-sensing information and external excitation signals, and to drive MEME results or special materials to modify the annular pressure equalization cavity structure, thereby realizing the self-driving and active regulation of the bearing state.

[0035] 6. The bearing plate cover is machined according to the preset dimensions using CNC machining, and a rigid connection with the bearing plate base is achieved through methods such as threaded connection.

Claims

1. A hydrostatic gas bearing with self-sensing and self-driving capability, characterized in that: The invention includes a bearing housing, a bearing plate, a toroidal throttling structure, and a sensing and driving mechanism within the toroidal throttling cavity. Because the pressure equalization cavity structure is transferred from the bearing housing surface to the working surface of the bearing plate, the bearing of this invention can achieve the effect of orifice throttling in the form of toroidal throttling, improving the bearing's load-bearing capacity while ensuring bearing stability. The sensing and driving mechanism inside the pressure equalization cavity, such as MEMS or PZT materials, can monitor the air film flow field, enabling real-time sensing of the bearing's performance. The sensing and driving mechanism inside the pressure equalization cavity, using special materials such as MEMS or PZT, can adjust the size or shape of the air film flow field while acquiring external excitation signals, thereby changing the characteristics of the air film flow field and controlling the bearing's performance. A microprocessor, such as a CPU or chip, can be integrated inside the bearing plate and connected to the sensing and driving mechanism inside the toroidal throttling cavity via a preset circuit, combined with intelligent control algorithms to achieve the bearing's self-sensing and self-driving characteristics.

2. The hydrostatic gas bearing according to claim 1 achieves the bearing effect of small-hole throttling by machining an annular pressure equalization cavity on the working surface of the bearing plate, while avoiding the occurrence of air hammer vibration.

3. The annular pressure equalizing cavity after processing is separated from the small hole on the surface of the bearing housing as described in claim 2. The processing of the pressure equalizing cavity will not affect the small hole, thereby reducing the processing difficulty of the bearing under the premise of the same performance and obtaining a processing cost far lower than that of traditional small hole throttling hydrostatic bearings.

4. The annular equalizing chamber according to claim 3 integrates a sensing device such as MEMS or PZT and other special materials. When the bearing vibrates, or the gas film pressure or gas film temperature changes, the sensing device can detect the changes in the above physical quantities, such as changes in the internal structure of the MEMS or materials, and convert them into corresponding electrical signal outputs, so that the annular orifice throttling static pressure gas bearing can synchronously sense signals such as vibration, gas film pressure, and gas film temperature.

5. The annular pressure equalization cavity according to claim 3 has an integrated driving device made of special materials such as MEMS or PZT. When the driving device receives an external excitation signal, it can generate a corresponding driving action according to the excitation signal, change the shape and size structure of the annular pressure equalization cavity, and thereby adjust the flow field characteristics in the gas film, so as to realize the working condition adaptability adjustment of the annular small hole throttling static pressure gas bearing.

6. The hydrostatic gas bearing according to claim 1, wherein a precision microcircuit is constructed in the bearing disk using processes such as ion implantation or photolithography; the microcircuit can realize the interconnection between various integrated devices inside the bearing disk, as well as the connection with an external excitation source.

7. The hydrostatic gas bearing according to claim 1, wherein a microprocessor is integrated inside the bearing disk, and the microprocessor is connected to the sensing device and the driving device inside the bearing disk through micro-circuits respectively to realize the bearing's self-sensing and self-driving functions; the microprocessor can also be connected to an external excitation source through micro-circuits, thereby enabling the bearing to have an active control function.

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