A smart tilting pad sliding bearing

Abstract

This invention discloses an intelligent tilting pad sliding bearing, comprising a bearing body with a through hole for a journal to pass through. An annular cavity filled with lubricating oil is formed between the inner circumferential wall of the through hole and the outer circumferential wall of the journal. Oil-blocking rings are provided at both ends of the annular cavity along its axial direction. Several pre-formed grooves are equally spaced along the circumferential direction on the inner circumferential wall of the through hole. A bearing bush adapted to the structure is slidably installed in the pre-formed groove along its axial direction. A guide rod that moves synchronously with the bearing bush is connected to the bearing bush. A limiting hole is provided on the bottom wall of the pre-formed groove, allowing only the guide rod to extend. An energy-dissipating part is provided on the side of each pre-formed groove away from the annular interval. The energy-dissipating part is provided with stiffness components that provide positive and negative stiffness to the bearing bush, respectively. The two stiffness components are spaced apart along the axial direction of the guide rod and are both connected to the portion of the guide rod extending out of the limiting hole. Through high static stiffness and low dynamic stiffness in the vibration direction, coordinated control of shaft vibration suppression and transmission isolation is achieved.

Description

Technical Field

[0001] This invention relates to the field of bearing technology, and in particular to an intelligent tilting pad sliding bearing. Background Technology

[0002] The elimination of mechanical vibration has a significant impact on the performance of mechanical equipment, necessitating various methods to isolate and eliminate vibration transmission. Common vibration reduction methods include active control and passive device methods. Active control methods involve using a series of control algorithms and devices to offset or reduce vibration. Passive device methods involve improving the structure to dissipate vibration energy along the transmission path, thereby reducing the impact of vibration on the equipment. Tilting pad bearings are among the most commonly used components in industry, and their vibration reduction performance affects the precision and reliability of equipment. Especially in recent years, with the development of modern industry, the requirements for bearings' ability to adapt to high speeds and harsh environments have become increasingly stringent.

[0003] A tilting pad bearing is a type of hydrodynamic sliding bearing, typically composed of several independent, freely tilting arc-shaped tilting pads at a support. During operation, the pads can freely oscillate in response to changes in load, speed, and temperature, generating hydrodynamic pressure in the lubricating oil film. This creates multiple oil wedges between the tilting pad surface and the journal surface, completely separating the two surfaces to reduce friction and damage, extending the bearing's service life. Furthermore, the pressure of each oil film always points towards the center, exhibiting high stability.

[0004] While existing tilting pad bearings can adequately meet the performance requirements of most applications, some specialized equipment demands even higher performance. For instance, underwater vehicles require extremely high acoustic stealth, placing stringent requirements on the bearing's low-frequency vibration damping capabilities. In helicopter tail drive systems, transcritical speed instability of the shafting under extreme conditions can lead to operational safety issues, necessitating stringent requirements for bearing vibration suppression and transmission isolation. Furthermore, real-time monitoring and early warning of bearing and shaft vibration are essential for proactive prevention. Existing tilting pad bearings cannot adequately meet the demands of these specialized applications. Summary of the Invention

[0005] The purpose of this invention is to provide an intelligent tilting pad sliding bearing to solve the problems existing in the prior art. By using high static stiffness and low dynamic stiffness in the vibration direction, it achieves coordinated control of shaft vibration suppression and transmission isolation. Furthermore, by constructing an adaptive control device, it achieves effective adaptive control of the system's damping, stiffness, and bearing temperature. At the same time, it can monitor the bearing's multi-dimensional service status information in real time.

[0006] To achieve the above objectives, the present invention provides the following solution: The present invention provides an intelligent tilting pad sliding bearing, comprising a bearing body, wherein a through hole is provided on the bearing body for a journal to pass through, and an annular cavity filled with lubricating oil is formed between the inner peripheral wall of the through hole and the outer peripheral wall of the journal. Oil-blocking rings are provided at both ends of the annular cavity along its axial direction to seal it. A plurality of pre-fabricated grooves are equally spaced along the circumference of the inner peripheral wall of the through hole. A bearing bush adapted to its structure is slidably and sealed along the axial direction within the pre-fabricated groove. A guide rod that moves synchronously with the bearing bush is connected to the bearing bush. A limiting hole is provided on the bottom wall of the pre-fabricated groove, allowing only the guide rod to extend. An energy-dissipating part is provided on the side of each pre-fabricated groove away from the annular interval. A stiffness component is provided on the energy-dissipating part to provide positive stiffness and negative stiffness to the bearing bush, respectively. The two stiffness components are spaced apart along the axial direction of the guide rod and are both connected to the portion of the guide rod extending out of the limiting hole.

[0007] Preferably, the energy-consuming part includes a cylindrical shell, one end of which has an opening for the guide rod to extend into, the stiffness component providing negative stiffness is fixed at the opening, the end of the guide rod extending out of the limiting hole is provided with a damping disc, and the stiffness component providing positive stiffness abuts against the inner wall of the bottom of the cylinder and the damping disc.

[0008] Preferably, the stiffness component providing negative stiffness is a cosine-type shallow groove disk structure, which includes a disk body located at its middle position and in force-transmitting contact with the guide rod, and a cosine beam of the cosine-type shallow groove disk structure surrounding the outer periphery of the disk body.

[0009] Preferably, the diameter of the cosine-type shallow groove disk structure is Rd, the radius of the cylinder is Rn, and Rn / Rd≈0.22.

[0010] Preferably, the disk body has an opening at its axis for the guide rod to pass through, and the guide rod is fixedly connected to a negative stiffness adjustment knob that can change the contact area with the disk body. The negative stiffness adjustment knob is located on the side of the disk body near the bearing and presses against the outer wall of the disk body.

[0011] Preferably, the negative stiffness adjustment knob is a threaded adjustment knob with a multi-layer structure. Its inner side is fixed to the guide rod, and its end away from the bearing abuts against the outer wall of the disc. A threaded structure is provided between adjacent layers to enable layer-by-layer movement along the axial direction of the guide rod.

[0012] Preferably, there is a cavity filled with damping fluid between the damping disc and the bottom of the cylinder. The side of the damping disc away from the bottom of the cylinder is provided with a damping cavity fixed to the guide rod. The damping cavity is in contact with and overlaps with the damping disc, and each has a plurality of corresponding and interconnected damping holes through which the damping fluid flows.

[0013] Preferably, the damping cavity has an annular structure, and its inner hole is provided with a rotating bearing that is rotatably connected to the guide rod.

[0014] Preferably, a temperature sensor and a semiconductor energy harvesting mechanism are provided on the side of the bearing bush away from the journal. The semiconductor energy harvesting mechanism is provided with a self-powered component capable of harvesting heat and converting it into electrical energy. The temperature sensor is electrically connected to the self-powered component for feedback. The semiconductor energy harvesting mechanism is also provided with a semiconductor structure for cooling the bearing bush and the lubricating oil according to the feedback information. The semiconductor structure is electrically connected to the self-powered component.

[0015] Preferably, a partition plate is fixedly connected inside the cylindrical outer shell. The partition plate has an opening for the guide rod to pass through. An electromagnetic energy harvesting self-powered mechanism is provided at the opening of the partition plate. An electromagnetic energy harvesting coil for the guide rod to pass through is provided on the electromagnetic energy harvesting self-powered mechanism. The electromagnetic energy harvesting coil is electrically connected to a displacement sensor for monitoring the vibration state of the guide rod.

[0016] The present invention achieves the following technical effects compared to the prior art:

[0017] First, when the journal rotates and vibrates, the vibration energy is dissipated by the lubricating oil in the annular cavity. Generally, the shaft system has high static stiffness, ensuring the bearing's large load-bearing capacity. Only when the shaft system reaches resonance at its cross-frequency does the bearing bush experience increased force, causing the lubricating oil film force to exceed the preload force of the stiffness components providing positive stiffness. The bearing bush moves axially along the pre-groove, introducing an additional liquid film zone, increasing the equivalent thickness of the oil film, and simultaneously causing a change in negative stiffness, reducing the shaft system's support stiffness. Since stiffness is related to the natural frequency, the natural frequency of the shaft system is lowered at this moment, thus avoiding resonance. That is, the bearing has lower dynamic stiffness, achieving better vibration isolation performance. Simultaneously, the movement of the bearing bush is transmitted to the energy dissipation section through the guide rod, causing the stiffness components providing positive and negative stiffness in the energy dissipation section to adaptively change and adjust, achieving high static stiffness and low dynamic stiffness of the system. High static stiffness ensures the bearing's large load-bearing capacity; while maintaining load, the system adaptively adjusts to low stiffness when the shaft system crosses its natural frequency, dissipating energy and avoiding resonance. The high static stiffness and low dynamic stiffness characteristics of the bearing achieve vibration suppression and transmission isolation of the shaft system, giving the bearing body advantages such as high load-bearing capacity, wide application range, and excellent vibration reduction performance.

[0018] Second, the stiffness component providing negative stiffness is a cosine-type shallow-groove disk structure. This structure includes a disk body located in its center and in contact with the guide rod for force transmission. A cosine beam of the cosine-type shallow-groove disk structure surrounds the outer periphery of the disk body, giving it good linearity in the vertical direction and thus negative stiffness characteristics. Ensuring the negative stiffness structural characteristics requires compression along the disk's axial direction; therefore, a guide rod is provided to ensure the normal service performance of the negative stiffness structure.

[0019] Third, an opening is provided at the center of the disc body for the guide rod to pass through. The guide rod is fixedly connected to a negative stiffness adjustment knob that can change the contact area with the disc body. The negative stiffness adjustment knob is located on the side of the disc body near the bearing bush and presses against the outer wall of the disc body. By changing the contact area between the guide rod and the disc body, i.e., the cosine shallow groove disc structure, the negative stiffness characteristics are changed, so that it can be quickly adapted to bearings under different working conditions.

[0020] Fourth, there is a cavity filled with damping fluid between the damping disc and the bottom of the cylinder. On the side of the damping disc away from the bottom of the cylinder, there is a damping cavity fixed to the guide rod. The damping cavity is in contact with and overlaps the damping disc, and each has several corresponding and interconnected damping holes through which the damping fluid flows. The damping fluid provides nonlinear damping force to the bearing body and can flow between the cavity and the damping cavity through the damping holes to change the magnitude of the nonlinear damping force of the bearing body, forming a squeeze film damper structure, which can achieve the function of shock resistance and ensure that the bearing bush can quickly return to stability.

[0021] Fifth, the guide rod has a deeply notched elliptical flexible ball hinge structure, which reduces the stiffness of the guide rod in the direction perpendicular to the axial direction by circumferentially slotting, thereby reducing the transmission of vibration in directions other than the axial direction.

[0022] Sixth, the structure integrates temperature and displacement sensors as well as energy harvesting devices to power them, enabling the bearing to have the ability to adaptively regulate temperature and monitor multi-dimensional service status information of the bearing while achieving adaptive power supply. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the overall structure of the bearing body of the present invention;

[0025] Figure 2 This is a cross-sectional view of the overall structure of the bearing body of the present invention;

[0026] Figure 3 This is an isometric view of the internal structure of the energy-consuming part of the present invention;

[0027] Figure 4 This is a schematic diagram of the internal structure of the energy-consuming part of the present invention;

[0028] Figure 5 This is a partial cross-sectional view of the bearing bush of the present invention;

[0029] Figure 6 This is a schematic diagram of the bearing housing structure of the present invention;

[0030] Figure 7 This is a schematic diagram of the oil-blocking ring structure of the present invention;

[0031] Figure 8 The force-displacement curve of the cosine structure;

[0032] Figure 9 This is the finite element model of the cosine-type shallow groove disk structure of the present invention;

[0033] Figure 10 The force-displacement and total elastic potential energy curves of the cosine shallow groove disk structure under different Rn conditions when Rd = 5mm are shown.

[0034] Figure 11 This is the damping structure model of the impact-resistant nonlinear damper of the present invention;

[0035] Figure 12 This invention relates to the relationship between the extrusion membrane damping, shear damping, total damping, and the bottom thickness h of the damping fluid.

[0036] Figure 13 The shear damping curves of different damping orifices in this invention;

[0037] Among them, 1-guide rod, 2-threaded adjustment knob, 3-cosine shallow groove disc structure, 4-cylindrical shell, 5-electromagnetic energy harvesting self-powered mechanism, 6-displacement sensor, 7-damping cavity, 8-damping disc, 9-linear positive stiffness spring, 10-journal, 11-bearing fixing part, 12-bearing bush, 13-semiconductor energy harvesting mechanism, 14-temperature sensor, 15-oil inlet, 16-bearing seat, 17-oil blocking ring, 18-energy dissipation part, 19-flexible hinge, 20-partition, 21-damping hole, 22-threaded mounting hole, 23-damping fluid. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all 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.

[0039] The purpose of this invention is to provide an intelligent tilting pad sliding bearing to solve the problems existing in the prior art. By using high static stiffness and low dynamic stiffness in the vibration direction, it achieves coordinated control of shaft vibration suppression and transmission isolation. Furthermore, by constructing an adaptive control device, it achieves effective adaptive control of the system's damping, stiffness, and bearing temperature. At the same time, it can monitor the bearing's multi-dimensional service status information in real time.

[0040] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] like Figures 1 to 13As shown, this embodiment provides an intelligent tilting pad sliding bearing, including a bearing body. The bearing body has a through hole for the journal 10 to pass through. An annular cavity filled with lubricating oil is formed between the inner peripheral wall of the through hole and the outer peripheral wall of the journal 10. Oil blocking rings 17 are provided at both ends of the annular cavity along its axial direction to seal it and prevent leakage. Preferably, the oil blocking rings 17 are threaded to the bearing body. The lubricating oil forms an oil film in the annular cavity to dampen the vibration of the journal 10. Several pre-made grooves are equally spaced along the circumference of the inner peripheral wall of the through hole. A bearing pad 12 adapted to its structure is slidably sealed along its axial direction in the pre-made groove. The bearing pad 12 is connected to a guide rod 1 that moves synchronously with it. The axis of the pre-made groove extends radially along the annular cavity. The guide rod 1 is coaxially arranged with the pre-made groove. The guide rod 1 adopts a flexible hinge 19 structure, which reduces the stiffness in the direction perpendicular to the axial direction of the guide rod, thereby reducing the transmission of vibration in the non-axial direction. The bottom wall of the precast groove is provided with a limiting hole for the guide rod 1 to extend out. Each precast groove has an energy dissipation part 18 on the side away from the annular interval. The energy dissipation part 18 is provided with stiffness components that provide positive stiffness and negative stiffness to the bearing shell 12 respectively, which can achieve high static stiffness and low dynamic stiffness in the vibration direction. The two stiffness components are spaced apart along the axial direction of the guide rod 1 and are connected to the part of the guide rod 1 that extends out of the limiting hole. The stiffness component that provides positive stiffness has a certain pre-compression amount, which applies a preload force to the bearing shell 12 through the guide rod 1. In the preferred initial state, the bearing shell 12 is flush with the groove opening of the precast groove and forms the same circumferential wall with the inner wall of the through hole to evenly bear the extrusion force of the lubricating oil. The bearing shell 12 and the energy dissipation part 18 are both installed in the bearing body. Preferably, four bearing shells 12 are arranged and evenly distributed in a circle, and an inverted pendulum support is used to decouple them from the other two orthogonal degrees of freedom.

[0042] When the journal 10 rotates and vibrates, the vibration energy is dissipated by the lubricating oil in the annular cavity. Only when the liquid film force of the lubricating oil exceeds the preload force of the stiffness component providing positive stiffness, the vibration of the journal 10 compresses the lubricating oil, causing a change in the lubricating oil area inside the annular cavity. This causes the bearing bush 12 to move axially along the pre-groove, introducing an additional liquid film zone and altering the effective damping and stiffness of the bearing body. Simultaneously, the movement of the bearing bush 12 is transmitted to the energy dissipation section 18 via the guide rod 1, causing the stiffness components providing positive and negative stiffness in the energy dissipation section 18 to adaptively change and adjust. This achieves high static and low dynamic stiffness of the system and suppression of shaft vibration, giving the bearing body advantages such as high load-bearing capacity, wide application range, and excellent vibration reduction performance. Furthermore, it can reduce the critical speed of the shaft system while ensuring the bearing's load-bearing capacity, achieving supercritical stable operation of the shaft system.

[0043] In a preferred embodiment of the present invention, the bearing body includes a bearing housing 16 and a bearing fixing part 11. The bearing housing 16 has an annular structure, and slots for installing energy-consuming parts 18 are evenly spaced on the inner peripheral wall of the inner hole of the bearing housing 16. The bearing fixing part 11 is fitted into the inner hole of the bearing housing 16 and the slots are sealed. When it is necessary to install or remove the energy-consuming part 18, the bearing fixing part 11 can be removed from the bearing housing 16, which is convenient for operation by those skilled in the art. The bearing fixing part 11 has a through hole for the journal 10 to pass through. The bearing fixing part 11 and the bearing housing 16 have oil inlets 15. Lubricating oil is filled into the annular cavity through the oil inlets 15, so that it wets the space between the bearing fixing part 11 and the journal 10, forming an oil film structure. After filling, the oil inlet 15 is sealed. Preferably, the bearing housing 16 has a threaded mounting hole 22 corresponding to the oil blocking ring 17, and a sealing ring or the like is squeezed between the oil blocking ring 17 and the bearing housing 16.

[0044] Furthermore, the energy-consuming part 18 includes a cylindrical outer shell 4. One end of the cylindrical outer shell 4 is provided with a cylindrical opening for the guide rod 1 to extend into. A stiffness component that provides negative stiffness is fixed at the cylindrical opening. A damping disk 8 is provided at the end of the guide rod 1 that extends out of the limiting hole. A stiffness component that provides positive stiffness abuts against the inner wall of the bottom of the cylinder and the damping disk 8. By providing the damping disk 8, the bearing surface of the guide rod 1 is increased, which facilitates the stiffness component that provides positive stiffness to support the damping disk 8, thereby facilitating the application of preload force to the bearing bush 12 through the guide rod 1.

[0045] The stiffness component providing negative stiffness is a negative stiffness curve disk, preferably a cosine-type shallow groove disk structure 3. Specifically, the outer peripheral edge of the cosine-type shallow groove disk structure 3 is connected to the inner peripheral edge of the cylindrical shell 4. The cosine-type shallow groove disk structure 3 includes a disk body located in its middle position and in force transmission contact with the guide rod 1. The cosine beam of the cosine-type shallow groove disk structure 3 surrounds the outer peripheral side of the disk body, giving it a negative stiffness characteristic with good linearity in the vertical direction. Preferably, to avoid affecting its deformation mode when subjected to non-vertical loads, the cosine-type shallow groove disk structure 3 adopts a flat thin-walled disk structure.

[0046] The preferred stiffness component providing positive stiffness employs multiple linear positive stiffness springs 9 evenly supported between the damping disc 8 and the bottom of the cylinder. These springs provide positive stiffness to the bearing, while the negative stiffness curve disc provides negative stiffness. It should be noted that lower bearing support stiffness can reduce the critical speed of the shaft system, facilitating stable operation at supercritical speeds. However, excessively low stiffness can lead to unstable support and misalignment. The nonlinear characteristics of high static stiffness and low dynamic stiffness in the bearing can solve the problems of high bearing load and supercritical stable operation of the shaft system, and also offer better vibration isolation performance, reducing vibration and minimizing vibration transmission from the bearing. High static stiffness and low dynamic stiffness can be achieved by connecting positive and negative stiffness in parallel.

[0047] Its typical force-displacement curve is as follows Figure 8 As shown, it is worth noting that the contact area and magnitude of the vertical pressure with the cosine beam structure affect the negative stiffness characteristics. Therefore, the radius of the top disk of the cosine disk affects its negative stiffness characteristics. Based on the multiphysics simulation software COMSOL Multiphysics, a finite element analysis was performed on the cosine disk structure. The diameter Rd of the cosine disk is set to 5 mm, and the radius of the top disk is Rn. The results are as follows: Figure 9 and Figure 10 As shown in the figure, the results indicate that as Rn increases, the range of negative stiffness gradually decreases, but the value of negative stiffness gradually increases, and the linearity of negative stiffness also gradually improves. When Rn = 1.1 mm, the linearity of negative stiffness is relatively high, and the force-displacement curve changes from an "upward convex" shape to a "downward concave" shape, indicating that the absolute value of negative stiffness decreases. This means that after applying a fixed value of positive stiffness in parallel, the near-zero stiffness value is positive in the near-zero stiffness region, and there is no small range of negative stiffness, thus ensuring structural stability. The analysis results show that Rn has a significant impact on the stiffness characteristics of the cosine disk. For a disk with a specific radius Rd, there exists an optimal Rn that results in the best negative stiffness characteristics. In this implementation case, when Rd = 5 mm and Rn / Rd ≈ 0.22, the negative stiffness value of the cosine disk structure is relatively large, the linearity is relatively high, and the range of high linearity is relatively large.

[0048] Furthermore, an opening is provided at the axis of the disc body for the guide rod 1 to pass through. The guide rod 1 is fixedly connected to a negative stiffness adjustment knob that can change the contact area with the disc body. The negative stiffness adjustment knob is located on the side of the disc body near the bearing 12 and presses against the outer wall of the disc body. By changing the contact area between the guide rod 1 and the disc body, i.e., the cosine shallow groove disc structure 3, the negative stiffness is changed.

[0049] In a preferred embodiment of the present invention, the negative stiffness adjustment knob is a threaded adjustment knob 2. The threaded adjustment knob 2 has a multi-layered structure, with its inner side fixed to the guide rod 1 and its end away from the bearing bush 12 pressing against the outer wall of the disc body. A threaded structure is provided between adjacent layers, enabling layer-by-layer movement along the axial direction of the guide rod 1. The radius of the guide rod 1 in contact with the cosine-type shallow groove disc structure 3 is changed by the threaded adjustment knob 2. The threaded adjustment knob 2 moves layer by layer via the thread. In the initial state, all the bottom surfaces of the threaded adjustment knob 2 are in contact with the cosine-type shallow groove disc structure 3, at which point the contact area is at its maximum. By rotating the threaded adjustment knob 2, the number of knob structure layers in contact with the cosine-type shallow groove disc structure 3 can be adjusted, moving layer by layer to change the size of the contact area, thereby adjusting the negative stiffness of the bearing.

[0050] The damping disk 8 has a cavity filled with damping fluid 23 between it and the bottom of the cylinder. A damping chamber 7, fixed to the guide rod 1, is located on the side of the damping disk 8 away from the bottom of the cylinder. Together, they form an impact-resistant nonlinear damper. The damping chamber 7 contacts and overlaps with the damping disk 8, and both have several corresponding, interconnected damping holes 21 through which the damping fluid 23 flows. The damping holes 21 on the damping disk 8 and the damping chamber 7 are equal in number and identical in structure. The damping fluid 23 provides nonlinear damping force to the bearing body and can flow between the cavity and the damping chamber 7 through the damping holes 21, thereby changing the magnitude of the nonlinear damping force on the bearing body and ensuring that the bearing bush 12 can quickly stabilize. A quantitative analysis of the damping structure of the impact-resistant nonlinear damper is performed, and its structural model is shown below. Figure 11 As shown.

[0051] When D1≈D2=D, the approximate analytical solution for the relationship between damping and each structural parameter is:

[0052]

[0053] Wherein, D1: the cylinder containing the upper damping fluid; D2: the inner diameter of the cylinder containing the lower damping fluid; d: the diameter of the damping orifice; h: the thickness of the bottom of the damping fluid; l: the length of the damping orifice; n: the number of damping orifices; η: the fluid dynamic viscosity coefficient.

[0054] The relationship between extrusion membrane damping, shear damping, total damping and the bottom thickness h of the damping fluid is as follows: Figure 12 As shown, the shear damping curves for different sizes of damping orifice 21 are as follows: Figure 13 As shown in the diagram, shear damping is independent of thickness h and is determined by the number of damping holes 21 and other structural parameters. The extrusion film damping has a large value when the thickness h is extremely small; after exceeding a certain limit, it decreases rapidly with increasing thickness h until it approaches zero. Total damping is the sum of shear damping and extrusion die damping, and its curve follows the same pattern as the extrusion die damping curve. When the number of damping holes 21 is small, shear damping decreases rapidly with increasing number of holes 21; as the number of holes 21 further increases, the decreasing trend of shear damping gradually flattens.

[0055] Furthermore, the damping cavity 7 has an annular structure, and its inner hole is equipped with a rotary bearing that is rotatably connected to the guide rod 1. By rotating the damping cavity 7, the size of the communication area of ​​the damping hole 21 between the damping cavity 7 and the damping disk 8 can be adjusted, thereby controlling the flow rate of the damping fluid 23. Preferably, the damping cavity 7 can also be fixedly connected to the guide rod 1 and sealed, and the damping disk 8 can be rotatably connected to the guide rod 1, specifically using a rotary bearing, so that the damping disk 8 rotates in a fixed position on the guide rod 1.

[0056] Furthermore, a temperature sensor 14 and a semiconductor energy harvesting mechanism 13 are located on the side of the bearing shell 12 away from the journal 10. The semiconductor energy harvesting mechanism 13 has a self-powered component capable of capturing heat and converting it into electrical energy. The temperature sensor 14 is electrically connected to the self-powered component for feedback. The semiconductor energy harvesting mechanism 13 also has a semiconductor structure that cools the bearing shell 12 and lubricating oil based on the feedback information. The semiconductor structure is made of a semiconductor material capable of cooling and is electrically connected to the self-powered component. When the temperature of the bearing body changes, the self-powered component of the semiconductor energy harvesting mechanism 13 captures heat energy and powers itself and the temperature sensor 14, monitoring the temperature change of the bearing. Because the oil film formed by the lubricating oil in the bearing body generates a large amount of heat due to its damping effect, excessively high temperatures will reduce the viscosity of the oil film, reduce the supporting effect, and affect the lubrication efficiency. Therefore, a semiconductor cooling chip material is covered on the outer surface of the bearing bush. The cooling and heat-absorbing surfaces of the semiconductor material are arranged in a cross pattern and pasted on the outer side of the bearing bush. The heat-absorbing surface is used to convert the energy of the bearing bush into electrical energy to power the sensor device. The temperature sensor 14 arranged on the outer side of the bearing bush serves as a feedback signal. When the temperature is higher than the set value, the power supply to the semiconductor structure used for cooling is actively cooled. When the temperature returns to the set value, the power supply is stopped, thereby realizing the adaptive control of the bearing body temperature.

[0057] The entire device can obtain multi-dimensional service status information such as viscosity, dynamic liquid film force, dynamic film thickness, eddy trajectory, and equivalent stiffness damping coefficient through a combination of integrated multiple sensors, high-precision transfer function model, fluid dynamics model and multi-dimensional information fusion method, so as to realize real-time monitoring of bearing multi-dimensional service status information.

[0058] In a preferred embodiment of the present invention, a partition 20 is fixedly connected inside the cylindrical outer shell 4. The partition 20 has an opening for the guide rod 1 to pass through. An electromagnetic energy harvesting self-powered mechanism 5 is located at the opening of the partition 20. An electromagnetic energy harvesting coil for the guide rod 1 to pass through is located on the electromagnetic energy harvesting self-powered mechanism 5. The electromagnetic energy harvesting coil is electrically connected to a displacement sensor 6 for monitoring the vibration state of the guide rod 1. The electromagnetic energy harvesting coil can capture vibration energy when the guide rod 1 moves and power itself and the displacement sensor 6. The displacement sensor 6 can measure the vibration of the damping cavity 7, thereby monitoring the movement of the bearing bush 12, and further monitoring the vibration of the bearing body. Preferably, the partition 20 and the damping cavity 7 are spaced apart, and the electromagnetic energy harvesting self-powered mechanism 5 and the displacement sensor 6 are both located at the spaced intervals on the side of the partition 20 closest to the damping cavity 7. Through the reasonable integration of the temperature sensor 14 and the displacement sensor 6, combined with a high-precision transfer function model, a fluid dynamics model, and a multi-dimensional information fusion method, multi-dimensional service state information such as viscosity, dynamic liquid film force, dynamic film thickness, eddy trajectory, and equivalent stiffness damping coefficient is obtained. The specific implementation method is as follows: Accurate fluid temperature is obtained by distributing temperature sensors outside the bearing bush, and fluid viscosity information is obtained based on the temperature-viscosity nonlinear curve. The vibration frequency and amplitude of the movable bearing bush are obtained using an eddy current displacement sensor. The dynamic oil film force is obtained through the oil film force-bearing bush displacement transfer function, and the vibration displacement and oil film thickness of the journal are obtained through the journal-bearing bush displacement transfer function. Based on this, the eddy current trajectory, eccentricity, and minimum film thickness of the journal inside the bearing can be obtained. Based on the established stiffness-damping equivalent model and the collected information, the bearing support stiffness and damping parameters can be obtained.

[0059] During the entire operation of the bearing body, when the journal 10 rotates and vibrates, the vibration energy of the shaft system is exchanged through the oil film formed by squeezing the lubricating oil, thus dissipating the energy and achieving vibration suppression. While a thicker oil film has a better vibration suppression effect, it has lower load-bearing and lubrication efficiency. A thinner oil film can withstand a large load but suffers from poor vibration suppression and temperature rise. Therefore, using the bearing body designed in this invention, when the shaft vibration is severe and the journal 10 squeezes the oil film, causing the vibration force of the oil film to exceed the preload applied by the linear positive stiffness spring 9, the bearing bush 12 moves along the pre-made groove, automatically increasing the area where the journal 10 squeezes the oil film, creating an additional fluid film area, introducing additional liquid film force, changing the effective damping and stiffness of the bearing body, increasing the amplitude of the journal 10, and further increasing the dissipation of vibration energy. Simultaneously, due to the aforementioned high static and low dynamic nonlinear stiffness support structure, the bearing bush 12 pushes the guide rod 1 to apply a vertical force to the negative stiffness curve disk, changing the negative stiffness of the bearing body. Furthermore, the guide rod 1 pushes the damping disk 8 to move, compressing the linear positive stiffness spring 9, changing the positive stiffness of the bearing body. The bearing body's support stiffness approaches zero, and the dynamic stiffness of the bearing bush 12 support structure is also near zero. This significantly reduces the vibration transmitted to the journal 10 and achieves coordinated control of shaft vibration suppression and transmission isolation. Furthermore, this invention allows for adjustments to bearing stiffness, damping, and preload according to the bearing's application, expanding its application range. This invention achieves high static and low dynamic stiffness in the vibration direction, effective damping and stiffness of the autonomous adjustment system, adaptive temperature control, real-time monitoring of multi-dimensional bearing service status information, and coordinated control of shaft vibration suppression and transmission isolation. It boasts advantages such as high reliability, wide application range, and excellent vibration reduction performance.

[0060] Any adaptive changes made according to actual needs are within the scope of protection of this invention.

[0061] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0062] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A smart tilting pad sliding bearing, characterized in that, The bearing includes a bearing body with a through hole for a journal to pass through. An annular cavity filled with lubricating oil is formed between the inner circumferential wall of the through hole and the outer circumferential wall of the journal. Oil-blocking rings are provided at both ends of the annular cavity along its axial direction. Several pre-made grooves are equally spaced along the circumferential direction on the inner circumferential wall of the through hole. A bearing bush adapted to its structure is slidably sealed in the pre-made groove along its axial direction. The bearing bush is connected to a guide rod that moves synchronously with it. A limiting hole is provided on the bottom wall of the pre-made groove for the guide rod to extend out. An energy-dissipating part is provided on the side of each pre-made groove away from the annular interval. The energy-dissipating part is provided with a stiffness component that provides positive stiffness and negative stiffness to the bearing bush, respectively. The two stiffness components are spaced apart along the axial direction of the guide rod and are connected to the part of the guide rod that extends out of the limiting hole. The energy-consuming part includes a cylindrical shell, one end of which is provided with a cylindrical opening for the guide rod to extend into. The stiffness component that provides negative stiffness is fixed at the cylindrical opening. The end of the guide rod that extends out of the limiting hole is provided with a damping disk. The stiffness component that provides positive stiffness abuts against the inner wall of the bottom of the cylinder and the damping disk. The stiffness component providing negative stiffness is a cosine-type shallow groove disk structure, which includes a disk body located at its middle position and in force-transmitting contact with the guide rod, and a cosine beam of the cosine-type shallow groove disk structure surrounding the outer periphery of the disk body. An opening is provided at the center of the disc for the guide rod to pass through. The guide rod is fixedly connected to a negative stiffness adjustment knob that can change the contact area with the disc. The negative stiffness adjustment knob is located on the side of the disc near the bearing and presses against the outer wall of the disc. The negative stiffness adjustment knob is a threaded adjustment knob with a multi-layer structure. Its inner side is fixed to the guide rod, and its end away from the bearing abuts against the outer wall of the disc. A threaded structure is provided between adjacent layers to enable layer-by-layer movement along the axial direction of the guide rod. There is a cavity filled with damping fluid between the damping disc and the bottom of the cylinder. The damping disc has a damping cavity fixed to the guide rod on the side away from the bottom of the cylinder. The damping cavity is in contact with and overlaps with the damping disc, and each has several corresponding and interconnected damping holes through which the damping fluid flows.

2. The intelligent tilting pad sliding bearing according to claim 1, characterized in that, The damping cavity has a ring-shaped structure, and a rotating bearing that is rotatably connected to the guide rod is provided in its inner hole.

3. The intelligent tilting pad sliding bearing according to claim 2, characterized in that, A temperature sensor and a semiconductor energy harvesting mechanism are provided on the side of the bearing away from the journal. The semiconductor energy harvesting mechanism is equipped with a self-powered component that can capture heat and convert it into electrical energy. The temperature sensor is electrically connected to the self-powered component for feedback. The semiconductor energy harvesting mechanism is also equipped with a semiconductor structure that cools the bearing and the lubricating oil according to the feedback information. The semiconductor structure is electrically connected to the self-powered component.

4. The intelligent tilting pad sliding bearing according to claim 3, characterized in that, A partition plate is also fixedly connected inside the cylindrical outer shell. The partition plate has an opening for the guide rod to pass through. An electromagnetic energy harvesting self-powered mechanism is provided at the opening of the partition plate. An electromagnetic energy harvesting coil for the guide rod to pass through is provided on the electromagnetic energy harvesting self-powered mechanism. The electromagnetic energy harvesting coil is electrically connected to a displacement sensor for monitoring the vibration state of the guide rod.

Images