A method, apparatus, equipment and storage medium for analyzing the performance of hydrostatic bearings.

Abstract

The present invention discloses a method, device, equipment and storage medium for analyzing the performance of a liquid hydrostatic bearing. The present invention models and simulates a servo hydraulic station and a liquid hydrostatic bearing as a whole, collects the pressure parameters of the hydraulic oil simulated and output by the servo hydraulic station sub-model to obtain the pressure fluctuation, and predicts the dynamic performance index of the liquid hydrostatic bearing according to the pressure parameter and the second parameter of the liquid hydrostatic bearing. Finally, the bearing performance is predicted according to the dynamic performance index of the bearing to obtain the bearing performance parameter. In the process of analyzing the performance of the liquid hydrostatic bearing, the present invention considers the influence of the oil pressure fluctuation of the servo hydraulic station on the performance of the liquid hydrostatic bearing, realizes accurate prediction of the performance of the liquid hydrostatic bearing, improves the processing quality of ultra-precision machining, and solves the technical problem that the simulation analysis method of the liquid hydrostatic bearing in the prior art cannot accurately predict the performance of the liquid hydrostatic bearing.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of simulation, and in particular to a method, device, equipment and storage medium for analyzing the performance of a liquid hydrostatic bearing. Background Art

[0002] The electromechanical hydraulic system is a comprehensive system that closely integrates mechanical, electrical and hydraulic systems to achieve the control and operation of various engineering equipment. The liquid hydrostatic bearing in the ultra-precision electromechanical hydraulic system uses externally supplied pressure oil to establish a hydrostatic load-bearing oil film in the bearing to achieve liquid-lubricated sliding bearings. At present, the simulation and analysis method of the liquid hydrostatic bearing only takes the liquid hydrostatic bearing as the research object, and studies the dynamic performance of the liquid hydrostatic bearing through numerical calculation. In the simulation process, the influence of the oil supply system on the performance of the liquid hydrostatic bearing is ignored, resulting in a certain deviation between the theoretical calculation results and the actual results, and thus it is impossible to accurately predict the performance of the liquid hydrostatic bearing.

[0003] In summary, the simulation analysis method of the liquid hydrostatic bearing in the prior art has the technical problem of being unable to accurately predict the performance of the liquid hydrostatic bearing. Summary of the invention

[0004] The embodiments of the present invention provide a method, device, equipment and storage medium for analyzing the performance of a liquid hydrostatic bearing, which solves the technical problem that the simulation analysis method for liquid hydrostatic bearings in the prior art cannot accurately predict the performance of liquid hydrostatic bearings.

[0005] In a first aspect, an embodiment of the present invention provides a method for analyzing performance of a hydrostatic bearing, comprising:

[0006] Calling a simulation model of the electromechanical-hydraulic system, the simulation model comprising a servo hydraulic station sub-model and a liquid hydrostatic bearing sub-model, the servo hydraulic station sub-model being used to simulate outputting hydraulic oil of a certain pressure to the liquid hydrostatic bearing sub-model;

[0007] Setting a first parameter of the servo hydraulic station sub-model;

[0008] Running the simulation model to obtain a first simulation result, wherein the first simulation result includes a pressure parameter of the hydraulic oil simulated and output by the servo hydraulic station sub-model;

[0009] determining a second parameter of the hydrostatic bearing sub-model;

[0010] Determining a bearing dynamic performance index of a liquid hydrostatic bearing sub-model according to the pressure parameter and the second parameter;

[0011] Predict bearing performance according to the bearing dynamic performance index to obtain bearing performance parameters;

[0012] When the bearing performance parameter meets the preset requirements, it is determined that the second parameter meets the design conditions.

[0013] Preferably, after obtaining the first simulation result, before determining the bearing dynamic performance index of the liquid hydrostatic bearing sub-model according to the pressure parameter and the second parameter, the method further includes:

[0014] The pressure parameters are preprocessed.

[0015] Preferably, the preprocessing of the pressure parameter comprises:

[0016] Invalid data in the pressure parameters are eliminated, and the retained pressure parameters are analyzed in the frequency domain.

[0017] Preferably, determining the bearing dynamic performance index of the liquid hydrostatic bearing sub-model according to the pressure parameter and the second parameter includes:

[0018] The pressure parameter and the second parameter are input into a preset transient Reynolds equation, the transient Reynolds equation is solved, and the bearing dynamic performance index of the liquid hydrostatic bearing sub-model is obtained.

[0019] Preferably, the bearing dynamic performance indicators include dynamic stiffness and dynamic damping.

[0020] Preferably, the bearing performance parameters include dynamic stability, rotation accuracy and in-position stability of the main shaft.

[0021] Preferably, when the bearing performance parameters do not meet the preset requirements, the first parameters and / or the second parameters are modified again, and the bearing performance parameters are determined based on the modified first parameters and / or second parameters until the bearing performance parameters meet the preset requirements.

[0022] In a second aspect, an embodiment of the present invention provides a liquid hydrostatic bearing performance analysis device, comprising:

[0023] A model building module, used to call a simulation model of the electromechanical hydraulic system, wherein the simulation model includes a servo hydraulic station sub-model and a liquid hydrostatic bearing sub-model, wherein the servo hydraulic station sub-model is used to simulate the output of hydraulic oil of a certain pressure to the liquid hydrostatic bearing sub-model;

[0024] A first parameter setting module, used to set a first parameter of the servo hydraulic station sub-model;

[0025] A model running module, used for running the simulation model to obtain a first simulation result, wherein the first simulation result includes a pressure parameter of the hydraulic oil simulated and output by the servo hydraulic station sub-model;

[0026] A second parameter determination module, used to determine a second parameter of the hydrostatic bearing sub-model;

[0027] A performance index determination module, used to determine the bearing dynamic performance index of the liquid hydrostatic bearing sub-model according to the pressure parameter and the second parameter;

[0028] A performance prediction module, used to predict bearing performance according to the bearing dynamic performance index to obtain bearing performance parameters;

[0029] The design meets the determination module, which is used to determine that the second parameter meets the design conditions when the bearing performance parameter meets the preset requirements.

[0030] In a third aspect, an embodiment of the present invention provides a liquid hydrostatic bearing performance analysis device, the liquid hydrostatic bearing performance analysis device comprising a processor and a memory;

[0031] The memory is used to store a computer program and transmit the computer program to the processor;

[0032] The processor is used to execute a method for analyzing performance of a liquid hydrostatic bearing as described in the first aspect according to instructions in the computer program.

[0033] In a fourth aspect, an embodiment of the present invention provides a storage medium storing computer executable instructions, wherein the computer executable instructions, when executed by a computer processor, are used to execute a method for analyzing performance of a liquid hydrostatic bearing as described in the first aspect.

[0034] The embodiment of the present invention discloses a method, device, equipment and storage medium for analyzing the performance of a liquid hydrostatic bearing. The embodiment of the present invention models and simulates a servo hydraulic station and a liquid hydrostatic bearing as a whole, collects the pressure parameters of the hydraulic oil simulated and output by the servo hydraulic station sub-model to obtain the pressure fluctuation, and predicts the dynamic performance index of the liquid hydrostatic bearing according to the pressure parameter and the second parameter of the liquid hydrostatic bearing, and finally predicts the bearing performance according to the bearing dynamic performance index to obtain the bearing performance parameter. In the process of analyzing the performance of the liquid hydrostatic bearing, the embodiment of the present invention considers the influence of the oil pressure fluctuation of the servo hydraulic station on the performance of the liquid hydrostatic bearing, realizes accurate prediction of the performance of the liquid hydrostatic bearing, improves the processing quality of ultra-precision machining, and solves the technical problem that the simulation analysis method of the liquid hydrostatic bearing in the prior art cannot accurately predict the performance of the liquid hydrostatic bearing. At the same time, the embodiment of the present invention also comprehensively designs and allocates parameters from an overall perspective, improves the matching between the servo hydraulic station and the liquid hydrostatic bearing, optimizes the performance of the electromechanical hydraulic system, and provides a reference for the matching design of the servo hydraulic station and the liquid hydrostatic bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the transmission process of pressure fluctuation in the related art.

[0036] Figure 2 It is a schematic diagram of the structure of the liquid hydrostatic guide rail oil pad in the related technology.

[0037] Figure 3 A flow chart of a method for analyzing performance of a liquid hydrostatic bearing provided in an embodiment of the present invention.

[0038] Figure 4 This is the system schematic diagram of the servo hydraulic station and liquid hydrostatic bearing in the electromechanical hydraulic system.

[0039] Figure 5 This is a schematic diagram of the specific working principles of the servo hydraulic station and liquid hydrostatic bearing.

[0040] Figure 6 A schematic flow chart of another method for analyzing performance of a liquid hydrostatic bearing provided in an embodiment of the present invention.

[0041] Figure 7 A schematic diagram of a method for analyzing performance of a liquid hydrostatic bearing provided in an embodiment of the present invention.

[0042] Figure 8 A schematic structural diagram of a liquid hydrostatic bearing performance analysis device provided in an embodiment of the present invention.

[0043] Fig. 9 A schematic structural diagram of a liquid hydrostatic bearing performance analysis device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0044] The following description and accompanying drawings fully illustrate the specific embodiments of the present application so that those skilled in the art can practice them. The examples represent possible variations only. Unless explicitly required, separate components and functions are optional, and the order of operation can vary. The parts and features of some embodiments may be included in or replace the parts and features of other embodiments. The scope of the embodiments of the present application includes the entire scope of the claims, and all available equivalents of the claims. In this article, each embodiment may be represented individually or generally by the term "invention", which is only for convenience, and if more than one invention is disclosed in fact, it is not intended to automatically limit the scope of the application to any single invention or inventive concept. In this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, without requiring or implying any actual relationship or order between these entities or operations. Moreover, the term "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method or device including a series of elements includes not only those elements, but also other elements that are not explicitly listed. The various embodiments are described in a progressive manner herein, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other. As for the structures, products, etc. disclosed in the embodiments, since they correspond to the parts disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0045] Liquid hydrostatic bearings in electromechanical hydraulic systems are widely used in precision and ultra-precision machining machines due to their performance advantages such as high rotation accuracy, high dynamic stiffness, high damping and vibration reduction, and long life. Liquid hydrostatic bearings mainly include liquid hydrostatic guides (planar motion pairs) and liquid hydrostatic spindles (rotational motion pairs). During operation, liquid hydrostatic bearings require an external oil supply device (hydraulic station) to provide them with working oil of a certain pressure. Precision and ultra-precision machining machines generally use servo hydraulic stations, that is, servo motors are used to drive hydraulic pumps, and closed-loop control is performed on the output pressure, striving to output working oil with relatively stable pressure fluctuations to the liquid hydrostatic bearings, which play a role in bearing and lubrication.

[0046] However, in the prior art, the pressure fluctuations of the working oil output by the servo hydraulic station cannot be completely eliminated. The objectively existing pressure fluctuations will have an adverse effect on the working performance of the liquid hydrostatic bearing, and this effect cannot be ignored during ultra-precision machining. Specifically, the core power element of the servo hydraulic station is the hydraulic pump. The periodic oil suction and oil pressure of the hydraulic pump cause periodic pressure fluctuations. At the same time, the opening and closing of other hydraulic components such as hydraulic valves will also cause pressure fluctuations. The pressure fluctuations of the working oil are transmitted along the flow path of the oil circuit, thereby causing the liquid hydrostatic bearing to vibrate. For example, the transmission process of pressure fluctuations is as follows: Figure 1 As shown, Figure 1 The schematic diagram of the transmission process of pressure fluctuation in the related technology. The pressure fluctuation originates from the hydraulic pump and other hydraulic components. It enters the oil chamber through the throttle and causes the pressure fluctuation inside the oil chamber, resulting in the dynamic change of the oil film thickness, thereby causing the slider or shaft core of the liquid hydrostatic guide to vibrate and thus affect the surface processing quality. Figure 2 It is a schematic diagram of the structure of the liquid hydrostatic guide rail oil pad in the related technology.

[0047] In the prior art, the performance analysis of liquid hydrostatic bearings is generally based on the premise that the pressure of the working oil is a constant value and there is no pressure fluctuation, and the performance of the liquid hydrostatic bearing is predicted by solving the dynamic Reynolds equation. However, this analysis method ignores the impact of the servo hydraulic station on the performance of the liquid hydrostatic bearing and does not consider the matching between the two, resulting in a certain deviation from the actual situation and the inability to accurately predict the bearing performance. In addition, the design of the servo hydraulic station mostly relies on experience. Even if simulation design is performed, it is generally limited to AMESim hydraulic performance simulation, which simplifies the impact of motor servo control on the pressure of the simulated output hydraulic oil. It does not coordinate the design and allocate parameters from the perspective of the system, resulting in poor matching between the servo hydraulic station and the liquid hydrostatic bearing, and the entire system cannot be optimized.

[0048] In order to solve the above technical problems, an embodiment of the present invention provides a method for analyzing the performance of a liquid hydrostatic bearing, such as Figure 3 As shown, Figure 3 A flow chart of a liquid hydrostatic bearing performance analysis method provided in an embodiment of the present invention. The liquid hydrostatic bearing performance analysis method provided in an embodiment of the present invention can be executed by a liquid hydrostatic bearing performance analysis device, and the liquid hydrostatic bearing performance analysis device can be implemented by software and / or hardware. The liquid hydrostatic bearing performance analysis device can be composed of two or more physical entities, or can be composed of one physical entity. For example, the liquid hydrostatic bearing performance analysis device can be a computer, a host computer, a tablet, or other equipment. The liquid hydrostatic bearing performance analysis method provided in an embodiment of the present invention includes the following steps:

[0049] Step 101, calling a simulation model of the electromechanical-hydraulic system, the simulation model including a servo hydraulic station sub-model and a liquid hydrostatic bearing sub-model, the servo hydraulic station sub-model is used to simulate the output of hydraulic oil of a certain pressure to the liquid hydrostatic bearing sub-model.

[0050] In this embodiment, the simulation model of the electromechanical hydraulic system needs to be called first. The simulation model of the electromechanical hydraulic system can be established in advance by the user according to the structure and principle of the electromechanical hydraulic system. Specifically, the system schematic diagram of the servo hydraulic station and the liquid hydrostatic bearing in the electromechanical hydraulic system is as follows: Figure 4As shown in the figure, the servo hydraulic station includes an oil tank, a filter, a hydraulic pump, a servo motor, a coupling, a relief valve, a pressure sensor, an accumulator and other accessories. The servo hydraulic station outputs hydraulic oil with a certain pressure and flow rate into the liquid hydrostatic guide through the throttle to play a role in bearing and lubrication. The specific working principle is as follows Figure 5 As shown, the hydraulic pump is the power unit of the entire hydraulic station. The hydraulic pump is driven by a servo motor and outputs hydraulic oil of a certain pressure and flow rate to the liquid hydrostatic bearing under the action of hydraulic valves and other accessories. At the same time, the pressure sensor feeds back the pressure signal of the hydraulic oil to the controller. The controller receives the pressure signal and outputs the control signal to the servo driver based on the PID control algorithm. The servo driver drives the servo motor to operate at a certain speed to control the pressure of the hydraulic oil. In addition, the liquid hydrostatic bearing includes a liquid hydrostatic spindle and a liquid hydrostatic guide rail. The oil supply pressure of the liquid hydrostatic spindle and the liquid hydrostatic guide rail is different. The oil supply pressure of the liquid hydrostatic guide rail is generally small. Therefore, before passing the hydraulic oil into the liquid hydrostatic guide rail, it is necessary to pass the hydraulic oil through a pressure reducing valve to reduce the pressure.

[0051] Exemplarily, the establishment of a servo hydraulic station sub-model is taken as an example for explanation. Since the servo hydraulic station uses a servo motor to drive the hydraulic pump, a pressure sensor is introduced to perform closed-loop control on the output pressure of the servo hydraulic station. Therefore, when establishing the servo hydraulic station sub-model, it is necessary to use AMESim-Simulink for joint modeling based on the schematic diagram of the servo hydraulic station. The servo motor and controller are modeled in Simulink, and the models of hydraulic components such as hydraulic pumps, hydraulic valves, and accumulators are established in AMESim, and the simulation interface is correctly set. The liquid hydrostatic bearing sub-model can be established with reference to the existing technology, and no specific limitation is made in this embodiment. After the user has established the servo hydraulic station sub-model and the liquid hydrostatic bearing sub-model, the servo hydraulic station sub-model and the liquid hydrostatic bearing sub-model can be associated to form a complete simulation model of the electromechanical-hydraulic system.

[0052] After the user has established the simulation model of the electromechanical-hydraulic system, the user can store the simulation model of the electromechanical-hydraulic system locally in the liquid hydrostatic bearing performance analysis device. When the user has simulation analysis requirements, the user can send a model call instruction to the liquid hydrostatic bearing performance analysis device so that the liquid hydrostatic bearing performance analysis device calls the local simulation model.

[0053] Step 102: Set the first parameter of the servo hydraulic station sub-model.

[0054] After calling the simulation model of the electromechanical hydraulic system, it is necessary to further set the first parameter of the servo hydraulic station sub-model. In this embodiment, the first parameter of the servo hydraulic station sub-model includes the displacement of the hydraulic pump, the volumetric efficiency and mechanical efficiency of the hydraulic pump, the volume and charging pressure of the accumulator, the valve core mass and spring stiffness of the overflow valve, and the electrical parameters of the servo motor. In this embodiment, the specific value of the first parameter can be pre-set by the user and stored locally in the liquid hydrostatic bearing performance analysis device. The liquid hydrostatic bearing performance analysis device sets the first parameter according to the locally stored value. In another embodiment, the liquid hydrostatic bearing performance analysis device can also automatically generate and set the specific value of the first parameter according to the simulation test requirements.

[0055] Step 103: run the simulation model to obtain a first simulation result, wherein the first simulation result includes pressure parameters of the hydraulic oil simulated and output by the servo hydraulic station sub-model.

[0056] After setting the first parameter of the servo hydraulic station sub-model, the simulation model can be run to start the servo hydraulic station sub-model, and the first simulation result can be obtained by collecting the pressure parameters of the hydraulic oil simulated and output by the servo hydraulic station sub-model during the operation. In one embodiment, after running the simulation model to obtain the output pressure parameters of the servo hydraulic station sub-model, the pressure parameters can be exported and saved as a TXT file. It can be understood that the pressure parameters include the fluctuation of the pressure.

[0057] Step 104: Determine the second parameter of the hydrostatic bearing sub-model.

[0058] While setting the first parameter of the servo hydraulic station sub-model, the second parameter of the liquid hydrostatic bearing sub-model also needs to be determined. It is understandable that in this embodiment, step 104 and step 102 can be performed simultaneously, and there is no need to perform step 103 before performing step 104. In this embodiment, the second parameter includes specific design parameters of the liquid hydrostatic bearing, such as bearing geometry (oil pad size), throttle hole diameter, oil film thickness, etc. The second design parameter can be determined according to the requirements of precision machining.

[0059] Step 105: Determine the bearing dynamic performance index of the liquid hydrostatic bearing sub-model according to the pressure parameter and the second parameter.

[0060] After the pressure parameter is obtained and the second parameter is set, the bearing dynamic performance index of the liquid hydrostatic bearing sub-model can be determined according to the pressure parameter and the second parameter. Exemplarily, after filtering and spectral analysis of the pressure parameter, the processed pressure parameter and the second parameter are input into the transient Reynolds equation of the established liquid hydrostatic bearing. The transient Reynolds equation is usually used to describe the flow of fluid on a rotating or moving surface, especially in lubrication theory, bearing analysis and fluid dynamics. The Reynolds equation is then solved using a finite difference or finite element method to obtain the bearing dynamic performance index. In one embodiment, the bearing dynamic performance index includes the dynamic stiffness and dynamic damping of the liquid hydrostatic bearing. The dynamic stiffness is used to describe the ability of the liquid hydrostatic bearing to resist deformation when subjected to dynamic loads (such as vibration or impact), and the dynamic damping is used to describe the ability of the liquid hydrostatic bearing to convert kinetic energy into other forms of energy during vibration or impact.

[0061] Step 106: predict bearing performance according to the bearing dynamic performance index to obtain bearing performance parameters.

[0062] After the bearing dynamic performance index is obtained, the bearing performance of the liquid hydrostatic bearing can be predicted. For example, when predicting the bearing performance, the dynamic stability, in-situ stability, and the axis motion trajectory of the liquid hydrostatic bearing can be predicted based on the bearing dynamic performance index, and the bearing performance parameters of the liquid hydrostatic bearing can be obtained based on the prediction results of the dynamic stability, the prediction results of the in-situ stability, and the prediction results of the axis motion trajectory of the spindle.

[0063] Step 107: When the bearing performance parameter meets the preset requirement, determine whether the second parameter meets the design condition.

[0064] After the bearing performance parameters are obtained, it can be determined whether the bearing performance parameters of the hydrostatic bearing meet the preset requirements, which are preset requirements that can be preset by the user. If the bearing performance parameters meet the preset requirements, the hydrostatic bearing performance analysis device determines that the second parameter meets the design conditions.

[0065] As mentioned above, the embodiment of the present invention provides a method for analyzing the performance of a liquid hydrostatic bearing. The embodiment of the present invention models and simulates the servo hydraulic station and the liquid hydrostatic bearing as a whole, collects the pressure parameters of the hydraulic oil simulated and output by the servo hydraulic station sub-model to obtain the pressure fluctuation, and predicts the dynamic performance index of the liquid hydrostatic bearing according to the pressure parameter and the second parameter of the liquid hydrostatic bearing. Finally, the bearing performance is predicted according to the dynamic performance index of the bearing to obtain the bearing performance parameter. In the process of analyzing the performance of the liquid hydrostatic bearing, the embodiment of the present invention considers the influence of the oil pressure fluctuation of the servo hydraulic station on the performance of the liquid hydrostatic bearing, realizes accurate prediction of the performance of the liquid hydrostatic bearing, improves the processing quality of ultra-precision machining, and solves the technical problem that the simulation analysis method of the liquid hydrostatic bearing in the prior art cannot accurately predict the performance of the liquid hydrostatic bearing. At the same time, the embodiment of the present invention also comprehensively designs and allocates parameters from an overall perspective, improves the matching between the servo hydraulic station and the liquid hydrostatic bearing, optimizes the performance of the electromechanical hydraulic system, and provides a reference for the matching design of the servo hydraulic station and the liquid hydrostatic bearing.

[0066] like Figure 6 As shown, Figure 6 A schematic diagram of a flow chart of another method for analyzing performance of a hydrostatic bearing provided by an embodiment of the present invention, Figure 6 The liquid hydrostatic bearing performance analysis method shown is a specific embodiment of the above-mentioned liquid hydrostatic bearing performance analysis method. The liquid hydrostatic bearing performance analysis method provided by the embodiment of the present invention includes:

[0067] Step 201, calling a simulation model of the electromechanical-hydraulic system, the simulation model includes a servo hydraulic station sub-model and a liquid hydrostatic bearing sub-model, the servo hydraulic station sub-model is used to simulate the output of hydraulic oil of a certain pressure to the liquid hydrostatic bearing sub-model.

[0068] Step 202: Set the first parameter of the servo hydraulic station sub-model.

[0069] Step 203: Run the simulation model to obtain a first simulation result, where the first simulation result includes the pressure parameters of the hydraulic oil simulated and output by the servo hydraulic station sub-model.

[0070] Step 204: pre-process the pressure parameters.

[0071] In this embodiment, after the pressure parameters are obtained, the output pressure result of the servo hydraulic station cannot be directly substituted into the subsequent transient Reynolds equation, so the pressure parameters need to be further preprocessed to eliminate invalid data in the pressure parameters. In one embodiment, the pressure parameters are preprocessed, including: eliminating invalid data in the pressure parameters, and performing frequency domain analysis on the retained pressure parameters. Specifically, the pressure parameters are first filtered to eliminate noise and interference in the pressure parameters to facilitate subsequent data processing. Afterwards, the retained pressure parameters are subjected to frequency domain analysis, such as Fourier transform and inverse Fourier transform.

[0072] Step 205: Determine the second parameter of the hydrostatic bearing sub-model.

[0073] Step 206: input the pressure parameter and the second parameter into a preset transient Reynolds equation, solve the transient Reynolds equation, and obtain the bearing dynamic performance index of the hydrostatic bearing sub-model.

[0074] After preprocessing the pressure parameter, the pressure parameter obtained after preprocessing and the second parameter can be input into the preset transient Reynolds equation, and the transient Reynolds equation is solved by the finite difference method or the finite element method to obtain the bearing dynamic performance index. Specifically, the specific formula of the transient Reynolds equation is as follows:

[0075]

[0076] In the formula,

[0077]

[0078] Λ x and Λ z is called the dimensionless bearing number, and σ is the extrusion number;

[0079] , ——dimensionless coordinates, ， ;

[0080] ——dimensionless time;

[0081] ——dimensionless oil film thickness, ;

[0082] ——dimensionless oil film pressure, ;

[0083] x,z ——Cartesian coordinates;

[0084] l c ——characteristic length (mm);

[0085] h ——Oil film thickness (μm);

[0086] h m ——Non-eccentric oil film thickness (μm), corresponding to the oil film thickness in the second parameter;

[0087] p ——Oil film pressure (Pa);

[0088] p s ——Oil supply pressure (Pa), which contains the perturbation term, corresponding to the preprocessed pressure parameter;

[0089] u 1 ，w 1 ——Liquid in x and z Speed ​​in direction (m / s);

[0090] - viscosity of the liquid;

[0091] V ——Reference speed.

[0092] In addition, the bearing geometry (oil pad size) and the throttle hole diameter in the second parameter are used to determine the calculation domain in the process of solving the transient Reynolds equation. The specific process can refer to the prior art and will not be repeated in this embodiment.

[0093] Step 207: predict bearing performance according to the bearing dynamic performance index to obtain bearing performance parameters, which include dynamic stability, rotation accuracy and in-situ stability of the main shaft.

[0094] In this embodiment, the bearing performance parameters include the dynamic stability, rotation accuracy and in-situ stability of the spindle. After obtaining the dynamic stiffness and dynamic damping of the liquid hydrostatic bearing, the bearing performance of the liquid hydrostatic bearing can be predicted according to the dynamic stiffness and dynamic damping to obtain the bearing performance parameters. Specifically, a dynamic model of the spindle system can be first established based on the working principle of the liquid hydrostatic bearing and parameters such as dynamic stiffness and dynamic damping. The dynamic model can reflect the vibration characteristics and stability of the spindle under dynamic loads. Afterwards, the dynamic model can be solved using numerical methods to obtain the dynamic response of the spindle under various working conditions. The dynamic response includes physical quantities such as displacement, velocity, and acceleration. Afterwards, the dynamic stability of the spindle is evaluated by analyzing its dynamic response. If the critical perturbation ratio of the spindle system is smaller and the critical mass is larger, the stability is better. Finally, predict its rotational accuracy and in-position stability. The rotational accuracy spindle refers to the range of spindle error motion. The spindle error motion refers to the spatial position error of the central axis of the spindle in the axial, radial and angular directions, the motion trajectory of the axis center, that is, the radial rotation error of the spindle. The rotational accuracy reflects the spindle's ability to maintain accuracy during rotation, while the in-position stability describes the stability of the spindle relative to its reference position when it is static or rotating at low speed.

[0095] Step 208: When the bearing performance parameter meets the preset requirement, determine whether the second parameter meets the design condition.

[0096] Step 209: if the bearing performance parameters do not meet the preset requirements, re-modify the first parameter and / or the second parameter, and determine the bearing performance parameters according to the re-modified first parameter and / or the second parameter until the bearing performance parameters meet the preset requirements.

[0097] In the case where the bearing performance parameters do not meet the preset requirements, it is necessary to modify the first parameter of the servo hydraulic station sub-model and / or the second parameter of the liquid hydrostatic bearing sub-model. In the case where the first parameter of the servo hydraulic station sub-model is modified, it is necessary to run the servo hydraulic station sub-model to obtain new pressure parameters, and re-solve the transient Reynolds equation based on the new pressure parameters and the second parameters to predict the bearing performance. In the case where the first parameter and the second parameter are modified at the same time, it is necessary to re-solve the transient Reynolds equation based on the new pressure parameters and the new second parameters to predict the bearing performance. In the case where only the second parameter is modified, it is necessary to re-solve the transient Reynolds equation based on the pressure parameters and the new second parameters to predict the bearing performance. The specific process is as follows. Figure 7 As shown, Figure 7 A schematic diagram of a method for analyzing performance of a liquid hydrostatic bearing provided in an embodiment of the present invention.

[0098] As mentioned above, the embodiment of the present invention provides a method for analyzing the performance of a liquid hydrostatic bearing. The embodiment of the present invention models and simulates the servo hydraulic station and the liquid hydrostatic bearing as a whole, collects the pressure parameters of the hydraulic oil simulated and output by the servo hydraulic station sub-model to obtain the pressure fluctuation, and substitutes the pressure parameters and the second parameter of the liquid hydrostatic bearing into the transient Reynolds equation and solves it to obtain the dynamic performance index of the liquid hydrostatic bearing. Finally, the bearing performance is predicted according to the dynamic performance index of the bearing to obtain the bearing performance parameter. In the process of analyzing the performance of the liquid hydrostatic bearing, the embodiment of the present invention considers the influence of the oil pressure fluctuation of the servo hydraulic station on the performance of the liquid hydrostatic bearing, realizes accurate prediction of the performance of the liquid hydrostatic bearing, improves the processing quality of ultra-precision machining, and solves the technical problem that the simulation analysis method of the liquid hydrostatic bearing in the prior art cannot accurately predict the performance of the liquid hydrostatic bearing. At the same time, the embodiment of the present invention also comprehensively designs and allocates parameters from an overall perspective, improves the matching between the servo hydraulic station and the liquid hydrostatic bearing, optimizes the performance of the electromechanical hydraulic system, and provides a reference for the matching design of the hydraulic station and the liquid hydrostatic bearing.

[0099] like Figure 8 As shown, Figure 8 A schematic diagram of the structure of a liquid hydrostatic bearing performance analysis device provided in an embodiment of the present invention. The liquid hydrostatic bearing performance analysis device provided in an embodiment of the present invention includes:

[0100] The model building module 301 is used to call the simulation model of the electromechanical hydraulic system, the simulation model includes a servo hydraulic station sub-model and a liquid hydrostatic bearing sub-model, the servo hydraulic station sub-model is used to simulate the output of hydraulic oil of a certain pressure to the liquid hydrostatic bearing sub-model;

[0101] A first parameter setting module 302, used to set a first parameter of the servo hydraulic station sub-model;

[0102] The model operation module 303 is used to operate the simulation model to obtain a first simulation result, wherein the first simulation result includes a pressure parameter of the hydraulic oil simulated and output by the servo hydraulic station sub-model;

[0103] A second parameter determination module 304, used to determine a second parameter of the hydrostatic bearing sub-model;

[0104] The performance index determination module 305 is used to determine the bearing dynamic performance index of the hydrostatic bearing sub-model according to the pressure parameter and the second parameter;

[0105] The performance prediction module 306 is used to predict the bearing performance according to the bearing dynamic performance index to obtain the bearing performance parameters;

[0106] The design compliance determination module 307 is used to determine whether the second parameter meets the design condition when the bearing performance parameter meets the preset requirement.

[0107] Based on the above embodiment, a preprocessing module is further included, which is used to preprocess the pressure parameter before determining the bearing dynamic performance index of the liquid hydrostatic bearing sub-model according to the pressure parameter and the second parameter after obtaining the first simulation result.

[0108] On the basis of the above embodiment, the preprocessing module is specifically used to remove invalid data in the pressure parameters and perform frequency domain analysis on the retained pressure parameters.

[0109] Based on the above embodiment, the performance index determination module 305 is specifically used to input the pressure parameter and the second parameter into a preset transient Reynolds equation, solve the transient Reynolds equation, and obtain the bearing dynamic performance index of the liquid hydrostatic bearing sub-model.

[0110] Based on the above embodiments, the dynamic performance indicators of the bearing include dynamic stiffness and dynamic damping.

[0111] Based on the above embodiments, the bearing performance parameters include the dynamic stability, rotation accuracy and in-position stability of the main shaft.

[0112] Based on the above embodiment, it also includes a parameter modification module, which is used to re-modify the first parameter and / or the second parameter when the bearing performance parameters do not meet the preset requirements, and determine the bearing performance parameters based on the re-modified first parameter and / or second parameter until the bearing performance parameters meet the preset requirements.

[0113] The liquid hydrostatic bearing performance analysis device provided in the embodiment of the present invention is included in the liquid hydrostatic bearing performance analysis equipment, and can be used to execute the liquid hydrostatic bearing performance analysis method provided in the above embodiment, and has corresponding functions and beneficial effects.

[0114] It is worth noting that in the embodiment of the above-mentioned liquid hydrostatic bearing performance analysis device, the various units and modules included are only divided according to functional logic, but are not limited to the above-mentioned division, as long as the corresponding functions can be achieved; in addition, the specific names of the functional units are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of the present invention.

[0115] This embodiment also provides a liquid hydrostatic bearing performance analysis device, such as Fig. 9 As shown, Fig. 9 A schematic diagram of a liquid hydrostatic bearing performance analysis device provided by an embodiment of the present invention is shown in FIG. Fig. 9 As shown, the liquid hydrostatic bearing performance analysis device 40 includes a processor 400 and a memory 401;

[0116] The memory 401 is used to store the computer program 402 and transmit the computer program 402 to the processor 400;

[0117] The processor 400 is used to execute the steps in the above-mentioned embodiment of the method for analyzing performance of a hydrostatic bearing according to the instructions in the computer program 402 .

[0118] Exemplarily, the computer program 402 may be divided into one or more modules / units, one or more modules / units are stored in the memory 401, and are executed by the processor 400 to complete the present application. One or more modules / units may be a series of computer program instruction segments capable of completing specific functions, and the instruction segments are used to describe the execution process of the computer program 402 in the liquid hydrostatic bearing performance analysis device 40.

[0119] The liquid hydrostatic bearing performance analysis device 40 may be a computing device such as a desktop computer, a notebook, a PDA, or a cloud server. The liquid hydrostatic bearing performance analysis device 40 may include, but is not limited to, a processor 400 and a memory 401. Those skilled in the art will appreciate that Fig. 9 It is merely an example of the liquid hydrostatic bearing performance analysis device 40 and does not constitute a limitation of the liquid hydrostatic bearing performance analysis device 40. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the liquid hydrostatic bearing performance analysis device 40 may also include input and output devices, network access devices, buses, etc.

[0120] The processor 400 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0121] The memory 401 may be an internal storage unit of the liquid hydrostatic bearing performance analysis device 40, such as a hard disk or memory of the liquid hydrostatic bearing performance analysis device 40. The memory 401 may also be an external storage device of the liquid hydrostatic bearing performance analysis device 40, such as a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), etc. equipped on the liquid hydrostatic bearing performance analysis device 40. Further, the memory 401 may also include both an internal storage unit and an external storage device of the liquid hydrostatic bearing performance analysis device 40. The memory 401 is used to store computer programs and other programs and data required by the liquid hydrostatic bearing performance analysis device 40. The memory 401 may also be used to temporarily store data that has been output or is to be output.

[0122] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0123] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0124] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0125] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0126] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store computer programs.

[0127] An embodiment of the present invention further provides a storage medium containing computer executable instructions, which are used to perform a method for analyzing the performance of a hydrostatic bearing when executed by a computer processor. The method includes the following steps:

[0128] Obtain resource information of the physical resources of each cloud platform connected, and synchronize the physical resources of each cloud platform based on the resource information;

[0129] The simulation model of the electromechanical hydraulic system is called. The simulation model includes a servo hydraulic station sub-model and a liquid hydrostatic bearing sub-model. The servo hydraulic station sub-model is used to simulate the output of hydraulic oil of a certain pressure to the liquid hydrostatic bearing sub-model.

[0130] Set the first parameter of the servo hydraulic station sub-model;

[0131] Running the simulation model to obtain a first simulation result, the first simulation result including a pressure parameter of the hydraulic oil simulated and output by the servo hydraulic station sub-model;

[0132] determining a second parameter of a hydrostatic bearing submodel;

[0133] Determining the bearing dynamic performance index of the liquid hydrostatic bearing sub-model according to the pressure parameter and the second parameter;

[0134] Predict bearing performance based on bearing dynamic performance indicators to obtain bearing performance parameters;

[0135] When the bearing performance parameter meets the preset requirements, it is determined that the second parameter meets the design conditions.

[0136] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the embodiments of the present invention are not limited to the specific embodiments herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the embodiments of the present invention. Therefore, although the embodiments of the present invention are described in more detail through the above embodiments, the embodiments of the present invention are not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the embodiments of the present invention, and the scope of the embodiments of the present invention is determined by the scope of the appended claims.

Claims

1. A method for analyzing the performance of a liquid hydrostatic bearing, characterized in that: include: Calling a simulation model of the electromechanical-hydraulic system, the simulation model comprising a servo hydraulic station sub-model and a liquid hydrostatic bearing sub-model, the servo hydraulic station sub-model being used to simulate outputting hydraulic oil of a certain pressure to the liquid hydrostatic bearing sub-model; Setting the first parameters of the servo hydraulic station sub-model; the first parameters include the displacement of the hydraulic pump, the volumetric efficiency and mechanical efficiency of the hydraulic pump, the volume and charging pressure of the accumulator, the valve core mass and spring stiffness of the overflow valve, and the electrical parameters of the servo motor; Running the simulation model to obtain a first simulation result, wherein the first simulation result includes a pressure parameter of the hydraulic oil simulated and output by the servo hydraulic station sub-model, wherein the pressure parameter includes a pressure fluctuation; Performing Fourier transform and inverse Fourier transform on the pressure parameter to obtain a preprocessed pressure parameter; Determining second parameters of the hydrostatic bearing sub-model; the second parameters include bearing geometry, orifice diameter, and oil film thickness of the hydrostatic bearing; Determining a bearing dynamic performance index of a liquid hydrostatic bearing sub-model according to the preprocessed pressure parameter and the second parameter; Predict bearing performance according to the bearing dynamic performance index to obtain bearing performance parameters; When the bearing performance parameter meets the preset requirement, determining that the second parameter meets the design condition; Wherein, determining the bearing dynamic performance index of the liquid hydrostatic bearing sub-model according to the preprocessed pressure parameter and the second parameter includes: Inputting the preprocessed pressure parameter and the second parameter into a preset transient Reynolds equation, solving the transient Reynolds equation, and obtaining the bearing dynamic performance index of the liquid hydrostatic bearing sub-model, wherein the bearing dynamic performance index includes dynamic stiffness and dynamic damping, and the bearing performance parameters include dynamic stability, rotation accuracy, and in-situ stability of the main shaft; In the case that the bearing performance parameters do not meet the preset requirements, the first parameters and / or the second parameters are modified again, and the bearing performance parameters are determined based on the modified first parameters and / or the second parameters until the bearing performance parameters meet the preset requirements.

2. A method for analyzing the performance of a liquid hydrostatic bearing according to claim 1, characterized in that: Before performing Fourier transform and inverse Fourier transform on the pressure parameter, the method further includes: Invalid data in the pressure parameters are eliminated.

3. A liquid hydrostatic bearing performance analysis device, characterized in that: include: A model building module, used to call a simulation model of the electromechanical hydraulic system, wherein the simulation model includes a servo hydraulic station sub-model and a liquid hydrostatic bearing sub-model, wherein the servo hydraulic station sub-model is used to simulate the output of hydraulic oil of a certain pressure to the liquid hydrostatic bearing sub-model; A first parameter setting module, used to set the first parameters of the servo hydraulic station sub-model; the first parameters include the displacement of the hydraulic pump, the volumetric efficiency and mechanical efficiency of the hydraulic pump, the volume and charging pressure of the accumulator, the valve core mass and spring stiffness of the overflow valve, and the electrical parameters of the servo motor; A model running module, used for running the simulation model to obtain a first simulation result, wherein the first simulation result includes a pressure parameter of the hydraulic oil simulated and output by the servo hydraulic station sub-model, wherein the pressure parameter includes a pressure fluctuation; A preprocessing module, used for performing Fourier transform and inverse Fourier transform on the pressure parameter to obtain a preprocessed pressure parameter; A second parameter determination module, used to determine the second parameters of the hydrostatic bearing sub-model; the second parameters include the bearing geometry, throttle hole diameter and oil film thickness of the hydrostatic bearing; A performance index determination module, used to determine the bearing dynamic performance index of the liquid hydrostatic bearing sub-model according to the preprocessed pressure parameter and the second parameter; A performance prediction module, used to predict bearing performance according to the bearing dynamic performance index to obtain bearing performance parameters; A design compliance determination module, used for determining that the second parameter meets the design condition when the bearing performance parameter meets the preset requirement; The performance index determination module is specifically used to input the preprocessed pressure parameter and the second parameter into a preset transient Reynolds equation, solve the transient Reynolds equation, and obtain the bearing dynamic performance index of the liquid hydrostatic bearing sub-model, wherein the bearing dynamic performance index includes dynamic stiffness and dynamic damping, and the bearing performance parameters include dynamic stability, rotation accuracy and in-situ stability of the main shaft; A parameter modification module is used to re-modify the first parameter and / or the second parameter when the bearing performance parameter does not meet the preset requirement, and determine the bearing performance parameter based on the re-modified first parameter and / or second parameter until the bearing performance parameter meets the preset requirement.

4. A liquid hydrostatic bearing performance analysis device, characterized in that: The liquid hydrostatic bearing performance analysis device includes a processor and a memory; The memory is used to store a computer program and transmit the computer program to the processor; The processor is used to execute a liquid hydrostatic bearing performance analysis method as described in any one of claims 1-2 according to instructions in the computer program.

5. A storage medium storing computer executable instructions, characterized in that: The computer executable instructions are used to execute a liquid hydrostatic bearing performance analysis method as described in any one of claims 1-2 when executed by a computer processor.

Images