A porous hydrostatic gas radial bearing based on piezoelectric shunt damping

Abstract

The present invention discloses a porous hydrostatic gas radial bearing based on piezoelectric shunt damping, belonging to the technical field of hydrostatic gas bearings; comprising a bearing housing, a bearing sleeve and a porous throttle axially arranged in the bearing housing, and a piezoelectric shunt damping module arranged between the bearing housing and the bearing sleeve and axially fixed by a retaining ring, wherein the piezoelectric shunt damping module is composed of a force amplifier, a piezoelectric ceramic stack, a pre-tightening block, a pre-tightening screw, a steel ball and a locking nut; the force amplifier is an axisymmetric structure composed of two trapezoidal connectors, four thin-walled beams and two end plates. The present invention sets a piezoelectric shunt damping module inside the bearing, converts the vibration mechanical energy of the bearing sleeve into electrical energy through the piezoelectric ceramic stack, and consumes the electrical energy generated by the piezoelectric ceramic stack through an external shunt resonant circuit to provide net damping for the bearing, thereby reducing the amplitude of the rotor relative to the bearing at high speed and improving the high-speed stability of the bearing.

Description

Technical Field

[0001] The present invention relates to a porous hydrostatic gas radial bearing, in particular to a porous hydrostatic gas radial bearing based on piezoelectric shunt damping, belonging to the technical field of hydrostatic gas bearings. Background Art

[0002] Bearings are key components of rotating machinery, supporting the rotating shaft, reducing wear on the shaft surface, and improving transmission efficiency. They are one of the core parts of the transmission system. As rotating machinery continues to develop towards higher speeds, higher power density, higher rotational precision, and higher efficiency, bearings are required to possess excellent characteristics such as zero friction, high load capacity, high precision, and high-speed stability.

[0003] Static gas bearings are supplied with air from an external source, forming an air film through a throttling device on the bearing surface. Compared to dynamic gas bearings, static gas bearings offer greater load-bearing capacity and excellent start-stop characteristics. As a specialized throttling device, the porous material is densely packed with micropores both inside and on the surface, creating a micron-scale lubricating air film within the bearing gap to support the rotor. Porous gas bearings are widely used in high-speed and high-precision rotating machinery due to their superior properties, such as high precision, low friction, high load-bearing capacity, and high speed.

[0004] However, the air film damping of the porous gas bearing at high speed is not enough to absorb the vibration of the rotor, and the high-speed stability of the bearing-rotor system is poor. An external damper needs to be installed to suppress the air film vortex. In order to improve the damping capacity of the porous bearing, the most common method is to use damping materials such as wire mesh and rubber to absorb vibration energy and dissipate it in the form of heat energy. For example, a damped gas hydrostatic bearing with authorization announcement number CN219888506U is provided, which arranges the damping sleeve between the bearing sleeve and the housing, and presses the bearing sleeve and the damping sleeve through a radially arranged fastening structure. By utilizing the damping characteristics of the damping sleeve, the bearing sleeve can undergo a small displacement under the action of the damping sleeve, so that the damping sleeve plays a damping role to improve the high-speed stability of the bearing.

[0005] At present, porous gas bearings using damping sleeves still have the following problems:

[0006] 1) Although damping materials such as wire mesh and rubber have certain damping capacity, their stiffness is relatively low and they cannot be connected in series with steel transmission components. Otherwise, the natural frequency of the transmission system will be reduced, causing a significant change in the natural frequency of the bearing-rotor system. Therefore, the stiffness of the damper must be greater than that of the bearing.

[0007] 2) Damping materials such as rubber and wire mesh rely on internal friction or Coulomb friction to generate damping, and the damping capacity they can provide is limited and cannot meet the damping requirements of high-speed bearing-rotor systems. When the bearing damping needs to be increased, it is necessary to increase the thickness of the damping sleeve to improve the damping capacity of the bearing. As the outer diameter of the bearing increases, the additional mass of the bearing also increases.

[0008] 3) Damping materials such as wire mesh and rubber convert the absorbed vibration energy into heat energy inside the material. If the generated heat energy cannot be dissipated from the bearing in time, the bearing temperature will rise, and the working environment of the bearing will deteriorate. In addition, rubber materials are prone to aging and have a short working life, while wire mesh has problems such as difficult processing and difficulty in ensuring processing accuracy.

[0009] Therefore, there is an urgent need to design a high-damping porous gas bearing with good high-speed stability and overall performance. Summary of the Invention

[0010] The purpose of the present invention is to solve the problem of insufficient damping capacity of porous hydrostatic gas radial bearings in the prior art, and to provide a porous hydrostatic gas radial bearing based on piezoelectric shunt damping, which converts the radial pressure of the bearing sleeve into axial pressure at both ends of the piezoelectric ceramic stack and amplifies the axial pressure. The positive piezoelectric effect of the piezoelectric ceramic stack and the external shunt resonant circuit are used to convert the vibration mechanical energy into electrical energy and remove it from the bearing-rotor system, thereby providing good net damping for the porous hydrostatic gas bearing, thereby reducing the amplitude of the rotor relative to the bearing at high speed and improving the high-speed stability of the bearing.

[0011] To achieve the above objectives, the present invention adopts the following technical solution: a porous hydrostatic gas radial bearing based on piezoelectric shunt damping, comprising a bearing housing, a bearing sleeve and a porous throttle axially disposed within the bearing housing, and a piezoelectric shunt damping module disposed between the bearing housing and the bearing sleeve and axially fixed by a retaining ring, wherein the piezoelectric shunt damping module is composed of a force amplifier, a piezoelectric ceramic stack, a preload block, a preload screw, a steel ball, and a locking nut;

[0012] The force amplifier is an axisymmetric structure consisting of two trapezoidal connectors, four thin-walled beams, and two end plates, wherein the two end plates are arranged vertically in parallel, and both ends of each end plate are laterally connected to thin-walled beams inclined inwards, and the two corresponding thin-walled beams on the two end plates are connected by a trapezoidal connector, and the connections between the thin-walled beams, the end plates, and the trapezoidal connectors are all connected by rounded transitions;

[0013] The centers of the two end plates are each provided with a threaded hole matching the pre-tightening screw, and the pre-tightening screw is connected to the end plate through the locking nut and the threaded hole in sequence; a piezoelectric ceramic stack is provided inside the force amplifier located between the two trapezoidal connectors, and both sides of the piezoelectric ceramic stack are in contact with and connected to pre-tightening blocks, and the pre-tightening blocks and the pre-tightening screws are each provided with a hemispherical groove on one end surface corresponding to the pre-tightening block, and a steel ball is connected with the surface between the two hemispherical grooves, and the steel ball cooperates with the hemispherical grooves on the pre-tightening block and the pre-tightening screw to form a spherical pair;

[0014] A connecting ring is provided on the axial middle outer cylindrical surface of the bearing sleeve along the circumferential direction, and the axial thickness of the connecting ring is the same as the thickness of the trapezoidal connecting head, and a plurality of trapezoidal connecting grooves are evenly distributed on the connecting ring; the bearing housing is arranged as an annular cylindrical structure, which is provided with a plurality of amplifier movable grooves evenly spaced along the circumferential direction, and a trapezoidal mounting groove is extended on the outer circumferential side of the amplifier movable groove, one of the trapezoidal connecting heads on the force amplifier is fitted and connected in the trapezoidal connecting groove, and the other trapezoidal connecting head is fitted and connected in the trapezoidal mounting groove.

[0015] The inclination angle of the thin-walled beam to the horizontal direction is set to 𝜃, and the inclination angle 𝜃 is 15°~25°, and the corresponding force amplification factor of the force amplifier is 2~3 times; the thickness H of the force amplifier is set to 8mm, the thickness t of the thin-walled beam is set to 0.5~1.2mm, the length L is set to 8~12mm, and the thickness h of the trapezoidal connector is set to 6mm.

[0016] The force amplifier is made of impact-resistant carbon steel material and is integrally formed by an electric spark wire cutting process.

[0017] The pre-tightening block is configured as a cubic column structure, one end of the pre-tightening block is provided with a shallow groove that cooperates with the piezoelectric ceramic stack, and the other end is configured as a hemispherical groove, and the center of the hemispherical groove is located on the center line of the axial direction of the pre-tightening block.

[0018] A plurality of arc-shaped pressure-equalizing groove blocks are evenly arranged in the circumferential direction on the inner cylindrical surface of the bearing sleeve. The porous throttle is an annular cylindrical structure and its outer cylindrical surface is glued and connected to the inner surface of the arc-shaped pressure-equalizing groove block. The porous throttle and the bearing sleeve together form a pressure-equalizing groove through the interval of the arc-shaped pressure-equalizing groove block; an air inlet hole connected to the pressure-equalizing groove is radially provided on the connecting ring, and an air inlet channel connected to the air inlet hole is radially provided on the bearing housing.

[0019] The retaining ring is configured as a full-circle annular structure, and a retaining ring mounting groove is provided on its circumference to axially cooperate with the bottom of the force amplifier. Connecting through holes are provided on the axial end face of the retaining ring and the axial end faces on both sides of the connecting ring, and the connecting through holes are staggered between the trapezoidal connecting groove and the retaining ring mounting groove. The retaining ring is fastened to both sides of the connecting ring by bolts passing through the connecting through holes to axially fix the piezoelectric shunt damping module.

[0020] The piezoelectric ceramic stack is also connected to a shunt resonant circuit, which includes a resistance element R and an inductance element L. The piezoelectric units in the piezoelectric ceramic stack are connected in series, and the electrodes between the piezoelectric units are connected in parallel.

[0021] The bearing housing is configured as two axially symmetrical annular cylindrical connection structures, which have multiple connection through holes evenly distributed along the axial direction and staggered with the amplifier movable groove. The two bearing housings are fixed by bolts, and the depth of their trapezoidal mounting grooves is half the thickness of the trapezoidal connector.

[0022] The pre-tightening screw is a hexagon socket fastening screw and adopts a fine-thread ordinary thread.

[0023] The beneficial effects of the present invention are:

[0024] 1) The present invention sets a piezoelectric shunt damping module inside the bearing, converts the vibration mechanical energy of the bearing sleeve into electrical energy through a piezoelectric ceramic stack, and consumes the electrical energy generated by the piezoelectric ceramic stack through an external shunt resonant circuit to provide net damping for the porous static pressure gas radial bearing, thereby reducing the amplitude of the rotor relative to the bearing at high speed, improving the high-speed stability of the bearing, and reducing the risk of friction between the rotor and the bearing at high speed.

[0025] 2) The force amplifier in the piezoelectric shunt damping module of the present invention converts the radial pressure of the bearing sleeve into the axial pressure of the force amplifier end plate. At the same time, the force amplifier amplifies the axial pressure of the end plate to the tangent of the angle between the thin-walled beam and the end plate and applies it to both ends of the piezoelectric ceramic stack, so that the output voltage of the piezoelectric ceramic stack increases by the same multiple as the force amplification factor. The shunt resonant circuit consumes more electrical energy under the output voltage of the piezoelectric ceramic stack, further improving the damping capacity of the porous bearing.

[0026] 3) The piezoelectric shunt damping module used between the bearing sleeve and the bearing housing in the present invention has an extremely high elastic modulus compared with damping materials such as rubber and wire mesh. After being connected in series with the bearing sleeve, it has little effect on the natural frequency of the bearing-rotor system; the piezoelectric shunt damping module uniformly distributed along the circumferential direction inside the bearing housing converts the vibration force of the bearing sleeve in any radial direction into the axial pressure of the piezoelectric ceramic stack, reducing the radial size of the bearing and making the bearing structure compact.

[0027] 4) In the present invention, a mechanical pre-tightening force is applied to the piezoelectric ceramic stack in the piezoelectric shunt damping module by using a torque wrench, thereby eliminating the assembly gap between the various parts of the damping module and ensuring that the piezoelectric ceramic stack always remains in a compressed state during oscillation; the steel ball eliminates the torsional shear stress generated when the pre-tightening screw is tightened, protecting the piezoelectric ceramic stack from damage.

[0028] 5) Compared with traditional dampers, the piezoelectric shunt damping module inside the bearing of the present invention converts vibration mechanical energy into reusable electrical energy, avoiding the heat energy generated by traditional damping materials inside the bearing and causing bearing temperature rise; the shunt circuit can also be integrated with monitoring sensors to monitor the operating status of the bearing, or to continuously power other low-power electronic devices in the transmission system, thereby solving the power supply needs of components such as sensors. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram of the exploded structure of the porous radial bearing of the present invention;

[0030] Figure 2 is a three-dimensional cross-sectional view of the porous radial bearing of the present invention;

[0031] Figure 3 is an axial cross-sectional view of the porous radial bearing of the present invention;

[0032] Figure 4 for Figure 1 Schematic diagram of the three-dimensional structure of the middle bearing sleeve;

[0033] Figure 5 for Figure 1 Front and left views of the force amplifier;

[0034] Figure 6 for Figure 1 Schematic diagram of the three-dimensional structure of the middle retaining ring;

[0035] Figure 7 for Figure 1 Schematic diagram of the three-dimensional structure of the middle bearing housing;

[0036] Figure 8 Schematic diagram of a shunt resonant circuit connected to a piezoelectric ceramic stack in the present invention.

[0037] In the figure, 1-porous throttle, 2-bearing sleeve, 201-connecting ring, 202-trapezoidal connecting groove, 203-air inlet, 204-arc-shaped equalizing pressure groove block, 205-equalizing pressure groove, 3-force amplifier, 301-trapezoidal connector, 302-thin-walled beam, 303-end plate, 304-threaded hole, 4-piezoelectric ceramic stack, 5-pre-tightening block, 6-pre-tightening screw, 7-steel ball, 8-retaining ring, 801-retaining ring mounting groove, 9-bearing housing, 901-amplifier movable groove, 902-trapezoidal mounting groove, 903-air inlet channel, 10-locking nut. DETAILED DESCRIPTION

[0038] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments.

[0039] Example: Figure 1 and Figure 2 As shown, the present invention provides a porous static pressure gas radial bearing based on piezoelectric shunt damping, including a bearing housing 9, a bearing sleeve 2 and a porous throttle 1 axially installed in the bearing housing 9, and a piezoelectric shunt damping module installed between the bearing housing 9 and the bearing sleeve 2 and axially fixed by a retaining ring 8, wherein the piezoelectric shunt damping module is composed of a force amplifier 3, a piezoelectric ceramic stack 4, a pre-tightening block 5, a pre-tightening screw 6, a steel ball 7 and a locking nut 10.

[0040] like Figure 3 and Figure 5 As shown, the force amplifier 3 is an axisymmetric structure consisting of two trapezoidal connectors 301, four thin-walled beams 302 and two end plates 303, wherein the two end plates 303 are arranged vertically in parallel, and both ends of each end plate 303 are laterally connected with a thin-walled beam 302 inclined inward, and the two corresponding thin-walled beams 302 on the two end plates 303 are connected by a trapezoidal connector 301, and the connections between the thin-walled beams 302 and the end plates 303 and the trapezoidal connector 301 are connected by rounded transitions, and the rounded corners of the connection parts avoid stress concentration; the force amplifier 3 is made of impact-resistant carbon steel material and is integrated and processed by electric spark wire cutting technology.

[0041] The amplification factor of the force amplifier 3 is mainly determined by the inclination angle 𝜃 of the thin-walled beam 302. The inclination angle 𝜃 of the thin-walled beam 302 to the horizontal direction is set to 15°~25°, and the corresponding force amplification factor of the force amplifier 3 is 2~3 times; the thickness H of the force amplifier 3 is set to 8mm, the thickness t of the thin-walled beam 302 is set to 0.5~1.2mm, the length L is set to 8~12mm, and the thickness h of the trapezoidal connector 301 is set to 6mm.

[0042] A threaded hole 304 matching the pre-tightening screw 6 is provided in the center of the two end plates 303, and the pre-tightening screw 6 passes through the locking nut 10 and the threaded hole 304 in sequence and is connected to the end plate 303; a piezoelectric ceramic stack 4 is installed inside the force amplifier 3 located between the two trapezoidal connectors 301, and both sides of the piezoelectric ceramic stack 4 are in contact with and connected to a pre-tightening pressure block 5, and a hemispherical groove is provided on the end surface corresponding to the pre-tightening pressure block 5 and the pre-tightening screw 6, and a steel ball 7 is connected with the surface between the two hemispherical grooves, and the steel ball 7 cooperates with the hemispherical grooves on the pre-tightening pressure block 5 and the pre-tightening screw 6 to form a spherical pair.

[0043] The pre-tightening block 5 is configured as a cubic column structure. One end of the pre-tightening block 5 is provided with a shallow groove that cooperates with the piezoelectric ceramic stack 4, and the other end is configured as a hemispherical groove, and the center of the hemispherical groove is located on the center line of the pre-tightening block 5 in the axial direction.

[0044] The piezoelectric ceramic stack 4 is located in the shallow grooves of the two pre-tightening blocks 5, which constrain the piezoelectric ceramic stack 4. The steel ball 7 cooperates with the hemispherical grooves of the pre-tightening block 5 and the pre-tightening screw 6 to form a spherical pair to transmit vibration force. The rotational freedom of the spherical pair eliminates the torsional shear stress generated when the pre-tightening screw 6 applies the pre-tightening force, thereby protecting the piezoelectric ceramic stack 4; the pre-tightening screw 6 is a hexagonal fastening screw with a fine-pitch ordinary thread, which forms a spiral pair with the threaded hole 304 on the end plate 303 to convert the spiral motion of the pre-tightening screw 6 into linear motion.

[0045] After the piezoelectric shunt damping module is assembled, in order to ensure that the piezoelectric ceramic stack 4 remains in a compressed state during vibration and eliminate the assembly gap between the various parts of the damping module, it is necessary to apply a pre-tightening force of 5~10N to it. By using a fixed torque wrench to tighten the pre-tightening screws 6 at both ends of the force amplifier 3, its spiral motion is converted into a linear motion of the steel ball 7 and the pre-tightening block 5 inside the damping module, and then the installation distance between the bottom surfaces of the shallow grooves of the two pre-tightening blocks 5 is adjusted. By adjusting the size of the installation distance, a mechanical pre-tightening force is applied to the piezoelectric ceramic stack 4.

[0046] A locking nut 10 is installed on the pre-tightening screw 6. After the pre-tightening force is applied to the piezoelectric ceramic stack 4 by the pre-tightening screw 6, the locking nut 10 is tightened so that it is tightened against the force amplifier end plate 303 to form friction anti-loosening, preventing the high-frequency vibration of the bearing from loosening the pre-tightening screw 6 and causing the piezoelectric shunt damping module to fail.

[0047] like Figure 4As shown, a plurality of arc-shaped pressure-equalizing groove blocks 204 are evenly arranged along the circumferential direction on the inner cylindrical surface of the bearing sleeve 2, and the porous throttle 1 is an annular cylindrical structure, and its outer cylindrical surface is glued and connected to the inner surface of the arc-shaped pressure-equalizing groove block 204. The porous throttle 1 and the bearing sleeve 2 are spaced apart by the arc-shaped pressure-equalizing groove blocks 204 to form a pressure-equalizing groove 205; an air inlet hole 203 connected to the pressure-equalizing groove 205 is radially opened on the connecting ring 201.

[0048] A connecting ring 201 is provided on the axial middle outer cylindrical surface of the bearing sleeve 2 in the circumferential direction, and the axial thickness of the connecting ring 201 is the same as the thickness of the trapezoidal connecting head 301, and its axial thickness is set to 6 mm. Three trapezoidal connecting grooves 202 are evenly distributed on the connecting ring 201.

[0049] like Figure 6 As shown, the retaining ring 8 is configured as a full-circle annular structure, and a retaining ring mounting groove 801 is provided on its circumference to axially cooperate with the bottom of the force amplifier 3. Connecting through holes are provided on the axial end face of the retaining ring 8 and the axial end faces on both sides of the connecting ring 201, and the connecting through holes are staggered between the trapezoidal connecting groove 202 and the retaining ring mounting groove 801. The retaining ring 8 is fastened to both sides of the connecting ring 201 by bolts passing through the connecting through holes to axially fix the piezoelectric shunt damping module.

[0050] like Figure 2 and Figure 7 As shown, the bearing housing 9 is configured as two axially symmetrical annular cylindrical connection structures. The two bearing housings 9 are fixed by bolts. Three connecting through holes are evenly distributed along the axial direction and are staggered with the amplifier movable groove 901. When the bearing sleeve 2 undergoes radial vibration movement, the amplifier movable groove 901 ensures the movable space required by the force amplifier 3.

[0051] The bearing housing 9 is configured as an annular cylindrical structure, which has three amplifier movable grooves 901 evenly spaced along the circumferential direction, and a trapezoidal mounting groove 902 extending from the outer circumferential side of the amplifier movable groove 901, with a groove depth of 3 mm. An air intake channel 903 connected to the air intake hole 203 is radially opened on the bearing housing 9; one of the trapezoidal connectors 301 on the force amplifier 3 is fitted and connected in the trapezoidal connecting groove 202, and the other trapezoidal connector 301 is fitted and connected in the trapezoidal mounting groove 902.

[0052] like Figure 8 As shown, a shunt resonant circuit is also connected to the piezoelectric ceramic stack 4. The shunt resonant circuit includes a resistance element R and an inductance element L. The piezoelectric units in the piezoelectric ceramic stack 4 are connected in series, and the electrodes between the piezoelectric units are connected in parallel.

[0053] The assembly process and working principle of the porous static pressure gas radial bearing are as follows:

[0054] A trapezoidal connecting groove 202 is provided on the bearing sleeve 2. After the trapezoidal connecting head 301 at one end of the force amplifier 3 in the piezoelectric shunt damping module is connected to the trapezoidal connecting groove 202 by form fit, the retaining ring 8 is installed on both sides of the bearing sleeve 2 and fastened by a bolt group to axially fix the form fit connection part, so that the bearing sleeve 2 and the piezoelectric shunt damping module are connected as a whole; then the trapezoidal connecting head 301 at the other end of the force amplifier 3 in the piezoelectric shunt damping module is installed into the trapezoidal mounting groove 902 of the bearing housing 9 for form fit connection, and the two bearing housings 9 cooperate to fix the piezoelectric shunt damping module and the bearing sleeve 2 and other components connected thereto. Finally, the two bearing housings 9 are pre-tightened by the bolt group;

[0055] The porous throttle 1 is attached to the inner surface of the arc-shaped pressure-equalizing groove block 204 by epoxy resin glue to fix and support the porous throttle 1; the axial end face of the porous throttle 1 and the end face mounting gap between the porous throttle 1 and the bearing sleeve 2 are sealed with epoxy resin glue to prevent the leakage of pressurized gas and reduce the bearing capacity of the bearing; the air inlet pipe of the external air source is connected to the air inlet hole 203 of the bearing sleeve 2 through the air inlet channel 903 of the bearing housing 9, and the pressurized gas is transported to the pressure-equalizing groove 205 and evenly diffused to the porous throttle 1, forming a lubricating gas film in the bearing gap to support the rotation of the rotor;

[0056] As the rotor speed gradually increases, the effect of the gas dynamic pressure effect gradually increases. The motion state of the porous gas bearing is affected by both the static pressure effect and the dynamic pressure effect. The absolute value of the cross-coupling stiffness coefficient increases rapidly with the increase in speed, resulting in a decrease in the bearing stability, forcing the bearing sleeve 2 to generate radial vibration motion and transmit its radial vibration motion to the piezoelectric shunt damping module. The piezoelectric shunt damping module converts the vibration mechanical energy into electrical energy and consumes the electrical energy through an external shunt resonant circuit, providing net damping for the porous static pressure gas radial bearing and improving the high-speed stability of the bearing.

[0057] The present invention sets a piezoelectric shunt damping module inside the bearing, converts the radial pressure of the bearing sleeve into axial pressure at both ends of the piezoelectric ceramic stack and amplifies the axial pressure, and utilizes the positive piezoelectric effect of the piezoelectric ceramic stack and the external shunt resonant circuit to convert the vibration mechanical energy into electrical energy and remove it from the bearing-rotor system, providing good net damping for the porous static pressure gas bearing, thereby reducing the amplitude of the rotor relative to the bearing at high speed and improving the high-speed stability of the bearing.

[0058] The above description is only used to illustrate the technical solution of the present invention and is not intended to limit the present invention. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in this field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. A porous hydrostatic gas radial bearing based on piezoelectric shunt damping, characterized by: It comprises a bearing housing (9), a bearing sleeve (2) and a porous throttle (1) axially arranged in the bearing housing (9), and a piezoelectric shunt damping module arranged between the bearing housing (9) and the bearing sleeve (2) and axially fixed by a retaining ring (8), wherein the piezoelectric shunt damping module is composed of a force amplifier (3), a piezoelectric ceramic stack (4), a pre-tightening block (5), a pre-tightening screw (6), a steel ball (7) and a locking nut (10); The force amplifier (3) is an axisymmetric structure consisting of two trapezoidal connectors (301), four thin-walled beams (302) and two end plates (303), wherein the two end plates (303) are arranged vertically in parallel, and both ends of each end plate (303) are laterally connected to thin-walled beams (302) inclined inwardly, and the two corresponding thin-walled beams (302) on the two end plates (303) are connected by the trapezoidal connector (301), and the connections between the thin-walled beams (302), the end plates (303) and the trapezoidal connector (301) are all connected by fillet transitions; The centers of the two end plates (303) are both provided with threaded holes (304) matching the pre-tightening screws (6), and the pre-tightening screws (6) are connected to the end plates (303) by sequentially passing through the locking nuts (10) and the threaded holes (304); a piezoelectric ceramic stack (4) is provided inside the force amplifier (3) located between the two trapezoidal connectors (301), and both sides of the piezoelectric ceramic stack (4) are in contact with pre-tightening blocks (5), and the pre-tightening blocks (5) and the pre-tightening screws (6) are both provided with hemispherical grooves on their corresponding end faces, and a steel ball (7) is connected between the two hemispherical grooves in a profile-matched manner, and the steel ball (7) is matched with the hemispherical grooves on the pre-tightening blocks (5) and the pre-tightening screws (6) to form a spherical pair; A connecting ring (201) is provided on the axial middle outer cylindrical surface of the bearing sleeve (2) along the circumferential direction, and the axial thickness of the connecting ring (201) is the same as the thickness of the trapezoidal connecting head (301), and a plurality of trapezoidal connecting grooves (202) are evenly distributed on the connecting ring (201); the bearing housing (9) is configured as an annular cylindrical structure, and a plurality of amplifier movable grooves (901) are evenly spaced along the circumferential direction, and a trapezoidal mounting groove (902) is extended on the outer circumferential side surface of the amplifier movable groove (901); one of the trapezoidal connecting heads (301) on the force amplifier (3) is connected in a fitting manner in the trapezoidal connecting groove (202), and the other trapezoidal connecting head (301) is connected in a fitting manner in the trapezoidal mounting groove (902).

2. The porous hydrostatic gas radial bearing based on piezoelectric shunt damping according to claim 1, characterized in that: The inclination angle of the thin-walled beam (302) to the horizontal direction is set to 𝜃, and the inclination angle 𝜃 is 15°~25°, and the corresponding force amplification factor of the force amplifier (3) is 2~3 times; the thickness H of the force amplifier (3) is set to 8mm, the thickness t of the thin-walled beam (302) is set to 0.5~1.2mm, the length L is set to 8~12mm, and the thickness h of the trapezoidal connector (301) is set to 6mm.

3. A porous hydrostatic gas radial bearing based on piezoelectric shunt damping according to claim 1 or 2, characterized in that: The force amplifier (3) is made of impact-resistant carbon steel material and is integrally formed by an electric spark wire cutting process.

4. The porous hydrostatic gas radial bearing based on piezoelectric shunt damping according to claim 1, characterized in that: The pre-tightening block (5) is configured as a cubic column structure, one end of the pre-tightening block (5) is provided with a shallow groove that cooperates with the piezoelectric ceramic stack (4), and the other end is configured as a hemispherical groove, wherein the center of the hemispherical groove is located on the center line of the axial direction of the pre-tightening block (5).

5. The porous hydrostatic gas radial bearing based on piezoelectric shunt damping according to claim 1, characterized in that: A plurality of arc-shaped equalizing pressure groove blocks (204) are evenly spaced along the circumferential direction on the inner cylindrical surface of the bearing sleeve (2); the porous throttle (1) is an annular cylindrical structure, the outer cylindrical surface of which is glued and connected to the inner surface of the arc-shaped equalizing pressure groove block (204); the porous throttle (1) and the bearing sleeve (2) are spaced apart by the arc-shaped equalizing pressure groove block (204) to form a equalizing pressure groove (205); an air inlet hole (203) in communication with the equalizing pressure groove (205) is radially provided on the connecting ring (201); and an air inlet channel (903) in communication with the air inlet hole (203) is radially provided on the bearing housing (9).

6. The porous hydrostatic gas radial bearing based on piezoelectric shunt damping according to claim 1, characterized in that: The retaining ring (8) is configured as a full-circle annular structure, and a retaining ring mounting groove (801) is provided on its circumference to axially match the bottom of the force amplifier (3). Connecting through holes are provided on the axial end face of the retaining ring (8) and the axial end faces on both sides of the connecting ring (201), and the connecting through holes are staggered between the trapezoidal connecting groove (202) and the retaining ring mounting groove (801). The retaining ring (8) is fastened to both sides of the connecting ring (201) by bolts passing through the connecting through holes to axially fix the piezoelectric shunt damping module.

7. The porous hydrostatic gas radial bearing based on piezoelectric shunt damping according to claim 1, characterized in that: The piezoelectric ceramic stack (4) is also connected to a shunt resonant circuit, which includes a resistance element R and an inductance element L, wherein the piezoelectric units in the piezoelectric ceramic stack (4) are connected in series, and the electrodes between the piezoelectric units are connected in parallel.

8. The porous hydrostatic gas radial bearing based on piezoelectric shunt damping according to claim 1, characterized in that: The bearing housing (9) is configured as two axially symmetrical annular cylindrical connection structures, each having a plurality of connection through holes evenly distributed along the axial direction and staggered with the amplifier movable groove (901). The two bearing housings (9) are fixed by bolt connection, and the depth of the trapezoidal mounting groove (902) is half the thickness of the trapezoidal connector (301).

9. The porous hydrostatic gas radial bearing based on piezoelectric shunt damping according to claim 1, characterized in that: The pre-tightening screw (6) is a hexagon socket fastening screw and adopts a fine-thread ordinary thread.

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