A polishing device for bearing machining and a polishing method thereof

Abstract

The application relates to the technical field of bearing machining, and discloses a polishing device for bearing machining and a polishing method thereof. The device comprises a polishing table, a polishing wheel, a motor one, a moving block, a rotary clamping assembly, a guide groove, a screw rod, a motor two, and a curved cooling water pipe and a nozzle integrated on the moving block. The method comprises the following steps: calculating energy coefficients and temperature coefficients representing grinding heat generation and heat load in real time; calculating cooling supply-heat load dynamic matching degrees and direction symbols based on the energy coefficients and the temperature coefficients and cooling parameters; calculating process stability coefficients based on acoustic emission and waviness signals; and finally comprehensively calculating and adjusting target cooling liquid injection pressure through a preset model by comprehensively considering the above coefficients and basic pressure. The application realizes real-time, accurate and self-adaptive matching of cooling supply and grinding heat load, and effectively improves the machining quality, stability and efficiency of bearing polishing.

Description

Technical Field

[0001] This invention belongs to the field of bearing processing technology, and particularly relates to a grinding device and grinding method for bearing processing. Background Technology

[0002] As a core component of mechanical transmission systems, the machining accuracy of bearings directly determines the smoothness of equipment operation, noise control level, and overall service life. In the bearing manufacturing process, the grinding process is crucial for ensuring that the dimensional tolerances and surface quality of the inner and outer rings meet standards. This process removes material through the relative motion between the grinding wheel and the workpiece, but simultaneously generates a large amount of grinding heat. Traditional bearing grinding equipment generally uses a fixed cooling system or a simple mechanical reciprocating structure, with coolant sprayed at a preset constant pressure and flow rate, making it impossible to dynamically adjust cooling parameters according to the real-time grinding conditions. This static cooling method causes multiple problems in practical applications: When rough grinding or high-load grinding is performed, the grinding force increases significantly, the material removal rate increases, and the heat load rises sharply. If the cooling supply is insufficient, the temperature in the grinding zone will quickly exceed the critical value, resulting in burn marks on the workpiece surface, irreversible changes in the metallographic structure, and even micro-cracks. These defects seriously weaken the fatigue strength and long-term operational reliability of the bearing. In the fine grinding or low-load stage, the heat load is lower. Excessive coolant not only wastes resources but also interferes with the contact stability between the grinding wheel and the workpiece due to the impact of the liquid flow, inducing an abnormal increase in surface waviness, thereby reducing machining accuracy and surface integrity. In recent years, some studies have attempted to regulate the cooling system by monitoring single parameters such as grinding temperature or motor power. However, these methods have significant shortcomings: First, they rely solely on isolated data such as temperature signals, failing to comprehensively analyze the coupling relationship between grinding energy input, material removal dynamics, and thermal load evolution. Second, they lack systematic modeling of the influence of parameters such as coolant jet flow rate and nozzle position relative to the grinding point, resulting in a lack of scientific basis for regulation strategies. Third, they fail to effectively integrate real-time process status information such as acoustic emission signal characteristics and surface waviness spectrum for machining stability assessment, leading to delayed cooling regulation response or over-adjustment, making it difficult to maintain continuous stability and quality consistency in the grinding process. Therefore, existing technologies struggle to achieve precise dynamic matching between cooling supply and grinding thermal load, severely restricting the quality improvement of precision bearing grinding.

[0003] To address the aforementioned issues, existing technologies urgently need improvement. Summary of the Invention

[0004] The purpose of this invention is to provide a grinding device and grinding method for bearing processing, in order to solve the above-mentioned problems.

[0005] This invention is implemented as follows: a grinding device for bearing processing includes a grinding table and a grinding wheel rotatably connected to the grinding table via a bracket. A motor connected to the grinding wheel is mounted on the side wall of the bracket. The device also includes a movable block, on which a rotary clamping assembly for driving the bearing to rotate is mounted. The movable block has a guide groove and is slidably connected within the guide groove. A lead screw is rotatably connected to the movable block, passing through and threadedly connected to it. A second motor is mounted on the side wall of the movable block, with its rotating end connected to the lead screw. A curved cooling water pipe is fixedly mounted on the movable block. A nozzle is fixedly mounted at one end of the curved cooling water pipe, and the other end of the curved cooling water pipe is connected to a cooling water tank via a hose and a water pump.

[0006] A further technical solution includes a rotating clamping assembly comprising a support plate one and a support plate two fixedly mounted on the top of the moving block. A telescopic shaft is telescopically connected to the side of the support plate one near the support plate two. A telescopic drive component is fixedly mounted on the other side of the support plate one. The telescopic end of the telescopic drive component is connected to one end of the telescopic shaft, and a conical clamping disc is rotatably connected to the other end of the telescopic shaft. A drive boss is rotatably connected to the side of the support plate two near the support plate one. A motor three is fixedly mounted on the other end of the support plate two, and the rotating end of the motor three is connected to the drive boss. The conical clamping disc and the drive boss are used to clamp the bearing, and the motor three is used to drive the bearing to rotate.

[0007] A grinding method for bearing processing includes the following steps: calculating an energy coefficient based on grinding force, material removal rate, and specific grinding energy; calculating a temperature coefficient based on the temperature of the workpiece grinding zone; calculating the dynamic matching degree of cooling supply-heat load and the direction sign based on the nozzle outlet flow rate and the distance from the nozzle to the grinding point under the energy coefficient and temperature coefficient; calculating a stability coefficient based on the acoustic emission signal characteristic value and the ripple spectrum characteristic value; and calculating the target coolant injection pressure based on the base pressure, the dynamic matching degree of cooling supply-heat load, the direction sign, and the stability coefficient, and adjusting the current coolant injection pressure to the target coolant injection pressure.

[0008] A further technical solution involves calculating the target coolant injection pressure as follows: obtaining the base pressure, the dynamic matching degree of cooling supply-heat load, the direction sign, and the stability coefficient; and importing the base pressure, the dynamic matching degree of cooling supply-heat load, the direction sign, and the stability coefficient into the formula. , obtain, among which, Based on pressure, Adjust the gain coefficient for pressure. For direction symbols, To achieve dynamic matching of cooling supply and heat load, This is the stability coefficient.

[0009] A further technical solution involves the following steps for calculating and obtaining the stability coefficient: obtaining the current acoustic emission signal feature value and the waviness spectrum feature value; performing maximum-minimum normalization on the current acoustic emission signal feature value and the waviness spectrum feature value to obtain the acoustic emission signal feature index and the waviness spectrum feature index; and performing a negative exponential transformation on the weighted sum of the acoustic emission signal feature index and the waviness spectrum feature index to obtain the stability coefficient. The stability coefficient ranges from 0 to 1, and a larger stability coefficient indicates a more stable processing process.

[0010] A further technical solution involves calculating the dynamic matching degree and directional sign of the cooling supply-heat load: obtaining the energy coefficient, temperature coefficient, nozzle outlet flow rate, and nozzle-to-grinding point distance; performing maximum-minimum normalization on both the current nozzle outlet flow rate and nozzle-to-grinding point distance to obtain the flow rate index and distance index; weighted summing of the energy coefficient and temperature coefficient to obtain the comprehensive heat load index, wherein both the energy coefficient and temperature coefficient are proportional to the comprehensive heat load index; and importing the comprehensive heat load index, flow rate index, and distance index into the formula. Obtain the dynamic matching degree of cooling supply and heat load. , , The larger the value, the more balanced the cooling supply and heat load demand are. The comprehensive heat load index, For traffic index, The distance index is used as the directional sign calculation function. The directional sign is obtained by substituting the comprehensive heat load index, flow rate index, and distance index into the directional sign calculation function. The directional sign calculation function is as follows: the sign is determined by the difference between the comprehensive heat load index and the combination of the flow rate index and the distance index. When the difference is positive, a positive sign is taken; when it is negative, a negative sign is taken; and when it is zero, a zero sign is taken.

[0011] A further technical solution involves the following steps for calculating the energy coefficient: obtaining the current grinding force, material removal rate, and specific grinding energy; performing maximum-minimum normalization on the current grinding force, material removal rate, and specific grinding energy to obtain the grinding force index, material removal rate index, and specific grinding energy index; substituting the grinding force index, material removal rate index, and specific grinding energy index into the energy coefficient calculation function to obtain the energy coefficient. The energy coefficient calculation function is a weighted sum of the grinding force index, material removal rate index, and specific grinding energy index, wherein the specific grinding energy index participates in the calculation in a complementary manner. The energy coefficient ranges from 0 to 1, and a larger energy coefficient indicates a higher energy state in the grinding process and a greater cooling requirement.

[0012] A further technical solution is to obtain the material removal rate and specific grinding energy by: obtaining the current grinding force, feed rate and grinding power; multiplying the current grinding force and feed rate to obtain the material removal rate; and comparing the current grinding power with the material removal rate to obtain the specific grinding energy.

[0013] A further technical solution involves the following steps for calculating the temperature coefficient: obtaining the temperature of the workpiece grinding zone; substituting the workpiece grinding zone temperature into a temperature coefficient calculation function to obtain the temperature coefficient. The temperature coefficient calculation function is based on the relationship between the workpiece grinding zone temperature and the preset optimal processing temperature and maximum safe temperature, calculating the temperature coefficient in segments. When the temperature does not exceed the optimal processing temperature, the temperature coefficient is 0. When the temperature exceeds the optimal processing temperature but does not exceed the maximum safe temperature, the temperature coefficient is calculated using an exponential function, where the exponent is the square of the standardized deviation of the temperature relative to the optimal processing temperature. When the temperature exceeds the maximum safe temperature, the temperature coefficient is 1. The temperature coefficient ranges from 0 to 1; a larger temperature coefficient indicates a higher heat load and a greater cooling demand.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] 1. Achieved dynamic and precise matching between cooling supply and grinding heat load: By integrating multiple sources of signals such as grinding force, temperature, cooling flow rate and distance, a dynamic matching degree model is established, which overcomes the problem of insufficient or excessive supply in the traditional fixed cooling mode, effectively preventing workpiece burn and deformation, and reducing coolant waste.

[0016] 2. Enhanced intelligence and stability of the grinding process: The system innovatively incorporates acoustic emission and surface waviness signals to calculate the stability coefficient and integrates it into the pressure control logic. When signs of instability appear in the process, the system prioritizes adjusting cooling parameters to restore stability, avoiding the negative impact of cooling shocks on machining quality and significantly improving the adaptability and consistency of the machining process.

[0017] 3. Improved machining quality and tool life: Through intelligent adjustment of multiple parameters, the grinding zone is always kept in good thermal management and process conditions, which not only improves the dimensional accuracy and surface integrity of the bearing, but also extends the service life of the grinding wheel by avoiding overheating and abnormal wear. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a grinding device for bearing processing provided by the present invention;

[0019] Figure 2 Provided by the present invention Figure 1 Schematic diagram of the rotating clamping assembly;

[0020] Figure 3 The flowchart illustrates a grinding method for bearing processing provided by this invention.

[0021] In the attached diagram: 1. Grinding table; 2. Support; 3. Motor 1; 4. Grinding wheel; 5. Moving block; 6. Guide groove; 7. Lead screw; 8. Motor 2; 9. Curved cooling water pipe; 10. Nozzle; 11. Support plate 1; 12. Support plate 2; 13. Telescopic shaft; 14. Telescopic drive component; 15. Conical clamping plate; 16. Drive boss; 17. Motor 3. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0024] like Figure 1 and Figure 2 As shown, a bearing processing grinding device according to an embodiment of the present invention includes a grinding table 1 and a grinding wheel 4 rotatably connected to the grinding table 1 via a bracket 2. A motor 3 connected to the grinding wheel 4 is installed on the side wall of the bracket 2. The device also includes a movable block 5, on which a rotary clamping assembly for driving the bearing to rotate is installed. A guide groove 6 is provided on the movable block 5, and the movable block 5 is slidably connected in the guide groove 6. A lead screw 7 is rotatably connected to the movable block 5, and the lead screw 7 passes through and is threadedly connected to the movable block 5. A second motor 8 is installed on the side wall of the movable block 5, and the rotating end of the second motor 8 is connected to the lead screw 7. A curved cooling water pipe 9 is fixedly provided on the movable block 5. A nozzle 10 is fixedly provided at one end of the curved cooling water pipe 9, and the other end of the curved cooling water pipe 9 is connected to a cooling water tank via a hose and a water pump. The cooling water tank is a container for storing coolant. The coolant is drawn from the cooling water tank by the water pump and transported to the nozzle 10 via the hose and the curved cooling water pipe 9.

[0025] In this embodiment of the invention, during operation, the rotating clamping assembly clamps and fixes the bearing and drives the bearing to rotate along its own axis. The output end of motor 3 is connected to the grinding wheel 4. Motor 3 drives the grinding wheel 4 to rotate, and motor 8 drives the lead screw 7 to rotate. Under the guidance of the guide groove 6, the lead screw 7 drives the moving block 5 to move through the threaded transmission. The moving block 5 drives the rotating clamping assembly and the bearing to move towards the grinding wheel 4, thereby realizing the supply of bearing grinding until the bearing contacts the grinding wheel 4. The grinding wheel 4 grinds the rotating bearing. The water pump draws coolant from the cooling water tank and delivers it to the nozzle 10 through the hose and the curved cooling water pipe 9. The nozzle 10 then sprays the coolant onto the bearing and the grinding wheel 4, thereby preventing surface burns, metallographic changes and the generation of microcracks, and significantly improving the processing quality and service life of the bearing.

[0026] like Figure 1 and Figure 2 As shown, in a preferred embodiment of the present invention, the rotating clamping assembly includes a support plate 11 and a support plate 12 fixedly mounted on the top of the movable block 5. A telescopic shaft 13 is telescopically connected to one side of the support plate 11 near the support plate 12, and a telescopic drive member 14 is fixedly mounted on the other side of the support plate 11. The telescopic end of the telescopic drive member 14 is connected to one end of the telescopic shaft 13, and a conical clamping disc 15 is rotatably connected to the other end of the telescopic shaft 13. A drive boss 16 is rotatably connected to one side of the support plate 12 near the support plate 11, and a motor 17 is fixedly mounted on the other end of the support plate 12. The rotating end of the motor 17 is connected to the drive boss 16. The conical clamping disc 15 and the drive boss 16 are used to clamp the bearing, and the motor 17 is used to drive the bearing to rotate.

[0027] In this embodiment of the invention, the telescopic drive member 14 can be a cylinder or a hydraulic cylinder. In the initial state, the telescopic drive member 14 is in a retracted state, the conical clamping plate 15 is away from the drive boss 16, the bearing is placed on the drive boss 16, the telescopic drive member 14 extends, the telescopic drive member 14 drives the telescopic shaft 13 to move, the telescopic shaft 13 drives the conical clamping plate 15 to move towards the drive boss 16, the conical surface on the conical clamping plate 15 plays a positioning role, the conical clamping plate 15 cooperates with the drive boss 16 to clamp the bearing, the motor 17 drives the drive boss 16 to rotate, the drive boss 16 drives the bearing and the conical clamping plate 15 to rotate, thereby realizing the positioning, clamping and rotation of the bearing.

[0028] like Figure 3As shown, in some other embodiments, this application proposes a grinding method for bearing processing, including the following steps: calculating an energy coefficient based on grinding force, material removal rate, and specific grinding energy; calculating a temperature coefficient based on the temperature of the workpiece grinding zone; calculating a dynamic matching degree of cooling supply-heat load and a direction sign based on the nozzle 10 outlet flow rate and the distance from the nozzle 10 to the grinding point under the energy coefficient and temperature coefficient; calculating a stability coefficient based on acoustic emission signal characteristic values ​​and ripple spectrum characteristic values; and calculating a target coolant injection pressure based on the base pressure, dynamic matching degree of cooling supply-heat load, direction sign, and stability coefficient, and adjusting the current coolant injection pressure to the target coolant injection pressure.

[0029] The core innovation of this embodiment lies in combining grinding force, material removal rate, specific grinding energy, and workpiece grinding zone temperature in a comprehensive index manner, and introducing acoustic emission signal characteristic values ​​and waviness spectrum characteristic values ​​for stability judgment, thereby achieving real-time dynamic matching between cooling supply and grinding heat load. Specifically, this method overcomes the limitation of traditional cooling systems relying solely on a single signal (such as temperature), establishes a coupling relationship model between energy coefficient and temperature coefficient, and incorporates acoustic emission signal characteristic values ​​and waviness spectrum characteristic values ​​into the stability coefficient calculation, effectively solving the problems of workpiece surface burns, metallographic structure changes, and decreased processing stability caused by insufficient or excessive cooling supply during grinding.

[0030] The solution proposed in this application can dynamically respond to changes in grinding conditions through the aforementioned technical means. For example, under heavy-load conditions with high grinding force and high material removal rate, the energy coefficient increases significantly. The system automatically improves the dynamic matching degree of cooling supply and heat load, and increases the target coolant injection pressure by adjusting the positive direction sign, ensuring timely heat dissipation in the grinding area. In the light-load or fine grinding stage, the stability coefficient increases due to the optimization of acoustic emission signal characteristic values ​​and waviness spectrum characteristic values. The system reduces the cooling pressure by adjusting the negative direction sign, avoiding an increase in surface waviness caused by liquid flow impact. This adjustment mechanism based on multi-source signal fusion not only comprehensively considers the dynamic coupling relationship between grinding energy, heat load, and process stability, but also achieves precise positioning and quantitative control of cooling supply through the normalization of nozzle 10 outlet flow rate and nozzle 10 to grinding point distance.

[0031] Through the above technical solution, this application significantly improves the adaptability and consistency of the bearing grinding process. When the temperature in the grinding zone is too high, the system responds quickly to suppress the risk of surface burn; when the process condition is stable, the cooling intensity is reasonably reduced to minimize resource waste. Overall, this method effectively bridges the gap between cooling supply and actual heat load demand, providing reliable technical support for the precision machining of bearings, and ultimately achieving the goal of improving machining quality and extending workpiece service life.

[0032] This application further proposes the following steps for calculating and obtaining the target coolant injection pressure:

[0033] The steps involve acquiring the base pressure, dynamic matching degree of cooling supply to heat load, direction sign, and stability coefficient. This step aims to provide the necessary input parameters for subsequent calculations of the target coolant injection pressure. These parameters can be obtained in various ways. For example, the base pressure can be preset to a process experience value or determined through preliminary experiments; the dynamic matching degree of cooling supply to heat load, direction sign, and stability coefficient can be calculated by real-time data acquisition from sensors using a preset algorithm, or retrieved from stored historical data.

[0034] Import the base pressure, cooling supply-heat load dynamic matching degree, direction sign, and stability coefficient into the formula. , obtain, among which, The base pressure represents the coolant injection pressure required under standard or ideal grinding conditions. This base pressure can be a fixed value, such as an empirical value preset based on bearing material, grinding wheel type, etc., or it can be a reference value that is dynamically adjusted according to the current machining task. This is the pressure adjustment gain coefficient, used to regulate the sensitivity and magnitude of coolant injection pressure adjustment. This gain coefficient can be set experimentally, through expert experience, or optimized online using an adaptive control algorithm to ensure the stability and accuracy of the system response. For example, an adaptive gain strategy can be employed, such as adjusting the gain coefficient when the matching degree... or stability coefficient If the gain remains consistently low (indicating an unstable transition process), temporarily reduce the gain. To prevent oscillations; during the stable phase, a higher gain is restored to improve the response speed; The direction symbol indicates the direction in which the coolant injection pressure needs to be adjusted. This direction symbol is usually a discrete value, such as +1 indicating that the pressure needs to be increased, -1 indicating that the pressure needs to be decreased, and 0 indicating that no adjustment is needed. Its specific value can be determined based on the matching between the cooling supply and the heat load. The dynamic matching degree of cooling supply and heat load quantifies the degree of matching between the current coolant supply and the heat load demand of the grinding zone. This matching degree can be a value between 0 and 1. The larger the value, the higher the matching degree and the more ideal the cooling effect. The stability coefficient reflects the stability of the grinding process. This coefficient can be a value between 0 and 1; a higher value indicates a more stable grinding process, such as less vibration and smaller fluctuations in grinding force. This step is the core calculation process, used to dynamically determine the coolant injection pressure based on real-time or estimated grinding conditions. The calculation of this formula can be implemented through programming by dedicated digital signal processors (DSPs), microcontrollers (MCUs), or industrial control computers (IPCs), or it can be performed rapidly through hardware logic circuits.

[0035] Direction symbols This determines the direction of pressure adjustment, that is, whether to increase or decrease the coolant injection pressure. This quantifies the magnitude of the adjustment: when the dynamic matching degree of cooling supply and heat load... and stability coefficient When both are relatively high, it indicates that the cooling effect is good and the process is stable. When the value is small, the adjustment range of the basic pressure is also small; conversely, when or A lower temperature indicates insufficient cooling or an unstable process. A larger value will result in a larger pressure adjustment range. Pressure adjustment gain coefficient. This is used to precisely control the sensitivity of such adjustments. In this way, the scheme can adaptively calculate the most suitable target coolant injection pressure based on the real-time status of the grinding process, thereby ensuring that the coolant supply is precisely matched with the actual needs of the grinding zone, effectively avoiding thermal damage caused by insufficient cooling or resource waste caused by excessive cooling.

[0036] As a specific implementation method, during the bearing grinding process, the control system can continuously monitor and acquire various parameters. For example, setting the base pressure. The pressure is 0.6 MPa. At a certain moment, the system calculates the dynamic matching degree of cooling supply and heat load. It is 0.65, direction sign. +1 (indicating insufficient cooling), stable It is 0.75. Meanwhile, the pressure adjustment gain coefficient... It is configured to 0.15. At this point, the control system substitutes these values ​​into the formula for calculation: The calculated pressure is 0.646 MPa. The control system then instructs the coolant supply unit to adjust the injection pressure to approximately 0.646 MPa. Through this dynamic calculation and adjustment, the coolant supply can precisely respond to the real-time demands of the grinding process, ensuring machining stability and quality.

[0037] Through the above technical solution, this application provides a method for accurately and dynamically calculating the target coolant injection pressure. Based on the aforementioned grinding method, this solution goes beyond simply evaluating individual influencing factors. Instead, it organically integrates key parameters such as base pressure, dynamic matching degree of cooling supply and heat load, direction sign, and stability coefficient through a unified mathematical model. This integration allows the adjustment of coolant injection pressure to fully consider the energy state, heat load demand, and process stability of the grinding process, thereby achieving refined control of coolant supply. Specifically, this method can intelligently adjust the coolant injection pressure according to the changing trend of heat load in the grinding zone and the stability of the process, avoiding the problem of mismatch between coolant supply and actual demand in traditional methods. This not only effectively suppresses grinding burns, reduces workpiece thermal deformation, and improves bearing machining accuracy and surface quality, but also optimizes coolant utilization efficiency, reduces production costs, and extends the service life of the grinding wheel.

[0038] This application further proposes the following steps for calculating the stability coefficient:

[0039] Acoustic emission signal characteristic values ​​and waviness spectrum characteristic values ​​are obtained. Acoustic emission signal refers to the phenomenon that internal stress waves release energy in the form of elastic waves during the deformation or fracture of a material. In grinding, acoustic emission signal can sensitively reflect the contact state between the grinding wheel and the workpiece, abrasive wear, crack initiation, and other microscopic dynamic processes. Its characteristic values ​​can be the root mean square (RMS) value, peak value, count rate, energy, etc., which can characterize the intensity and abnormalities of the grinding process. Acquisition can be achieved by real-time signal acquisition using an acoustic emission sensor installed near the grinding area, followed by extraction of corresponding characteristic values ​​by a signal processing unit. Another method is to indirectly capture vibration information related to acoustic emission using a high-frequency vibration sensor and perform spectral analysis to extract features. Waviness refers to the microscopic undulations on the workpiece surface beyond macroscopic flatness, and is an important indicator for measuring the quality of the machined surface. During grinding, the formation of waviness is closely related to grinding vibration, grinding force fluctuations, and grinding wheel wear. Waviness spectral characteristics are typically obtained through spectral analysis, such as Fourier transform, of workpiece surface topography data, including energy, amplitude, or dominant frequency components within a specific frequency range. These characteristics reflect the dynamic stability of the grinding process and the potential trend in surface quality. One method is to acquire workpiece surface topography data using online or offline optical measurement equipment (such as white light interferometers or laser scanners), followed by digital signal processing to obtain spectral characteristics. Another method is to use contact or non-contact sensors (such as eddy current sensors or laser displacement sensors) to measure the vibration of the workpiece or grinding wheel in real time, and indirectly evaluate waviness characteristics by analyzing its spectrum.

[0040] The current acoustic emission signal eigenvalues ​​and ripple spectrum eigenvalues ​​are normalized to their maximum and minimum values ​​to obtain the acoustic emission signal characteristic index and ripple spectrum characteristic index. This aims to transform data with different dimensions or value ranges into a unified interval, facilitating comparison and fusion between different features. Its function is to eliminate the influence of dimensions, preventing certain features from dominating subsequent calculations due to their large values, thus ensuring that all features contribute relatively fairly to the final result. The processing method typically involves subtracting the minimum value of the feature from each data point and then dividing by the difference between the maximum and minimum values ​​of that feature.

[0041] The stability coefficient is obtained by performing a negative exponential transformation on the weighted sum of the acoustic emission signal characteristic index and the waviness spectrum characteristic index. The stability coefficient ranges from 0 to 1, and a larger stability coefficient indicates a more stable processing process. Specifically, the acoustic emission signal characteristic index and the waviness spectrum characteristic index are imported into the formula... To obtain the stability coefficient , Stability coefficient A larger value indicates a more stable machining process. When the grinding process is very stable... and Approaching 0, at this point When the value approaches 1, significant instability occurs in the grinding process. and Increasing the value of the exponent term leads to an increase in the absolute value of its negative value, thereby increasing the absolute value of the exponent term. It decreases rapidly and approaches 0. Therefore, A higher value directly reflects a higher stability in the grinding process, while a lower value indicates lower stability. Among these, The acoustic emission signal weight is a parameter between 0 and 1 used to adjust the relative importance of the acoustic emission signal characteristic index in the stability coefficient calculation. The value can be determined based on the specific processing material, grinding method, or experience, focusing on the impact of acoustic emission signal or ripple spectrum signal on stability. The determination of the weight can be achieved by introducing an online adaptive rule based on the processing stage or material removal rate. For example, in the rough grinding stage (high material removal rate), the acoustic emission signal can be given a higher weight, while in the fine grinding stage, the waviness signal can be given a higher weight. The characteristic index of acoustic emission signal. The two indices are the acoustic emission signal characteristic values ​​and the waviness spectrum characteristic values ​​after max-min normalization. They represent the relative instability of the grinding process in terms of acoustic emission and surface quality. This formula uses an exponential function to express the normalized acoustic emission signal characteristic indices. and ripple spectral characteristic index Weighted fusion is performed and mapped to a specific interval. The use of an exponential function makes the grinding process more unstable (i.e., and The larger the value, the more significant the abnormal signal and surface defects. The value will decrease rapidly, and conversely, it will approach 1.

[0042] This application's solution achieves precise quantification of grinding process stability by comprehensively considering acoustic emission signals and workpiece surface waviness information during the grinding process. First, the characteristic values ​​of the acoustic emission signals generated during grinding and the spectral characteristic values ​​of the workpiece surface waviness are acquired in real time. The acoustic emission signals reflect the dynamics of microscopic contact and energy release in the grinding zone, while the waviness spectral characteristic values ​​characterize the fluctuations in macroscopic machining quality. To eliminate the influence of different physical dimensions and numerical ranges on stability assessment, these original characteristic values ​​are subjected to max-min normalization to obtain dimensionless acoustic emission signal characteristic indices and waviness spectral characteristic indices. These indices can uniformly reflect the degree of instability of the grinding process in different dimensions. Subsequently, these two normalized indices are imported into an exponential function formula, and weighting coefficients are introduced. This is used to balance the contributions of the acoustic emission signal and the ripple spectrum signal to stability. The stability coefficient is calculated using this formula. Its value ranges between (0,1], and a larger value indicates a more stable grinding process. This calculation method allows for the calculation of the grinding process when slight instability occurs. The value will decrease moderately; however, when severe instability occurs, The value will decrease significantly, thus enabling sensitive detection of changes in the grinding state.

[0043] This stability coefficient Obtaining the target coolant injection pressure provides a crucial input parameter for the aforementioned method of calculating the target coolant injection pressure. In the above method, the target coolant injection pressure... The calculation formula is By precisely quantizing the stability coefficient Substituting this formula allows the adjustment of coolant injection pressure to consider not only the matching degree between heat load and cooling supply, but also the stability of the grinding process itself. When the grinding process is unstable ( When the value is small, the formula in The value will increase relatively, thus causing the target coolant injection pressure to adjust more significantly according to the direction sign, all other things being equal, in order to quickly restore process stability or optimize cooling performance. For example, if the direction sign indicates that increased cooling is needed, the lower value will be adjusted accordingly. This will cause the pressure to increase further; if the directional sign indicates that cooling needs to be reduced, then lower... This will further reduce pressure to avoid the negative effects of overcooling. This pressure regulation mechanism, based on real-time stability assessment, enables the cooling strategy to be more intelligent and adaptive, thus effectively coping with various complex working conditions that may occur during the grinding process.

[0044] As a specific implementation method, the stability coefficient can be obtained during the bearing grinding process using the following steps. First, a broadband acoustic emission sensor is installed near the grinding table 1 to collect acoustic emission signals from the grinding area in real time, and the root mean square (RMS) value is extracted as the acoustic emission signal feature value using a digital signal processor. Simultaneously, after grinding or via an online detection device, a laser displacement sensor scans the bearing surface to obtain its surface morphology data, and this data is processed by Fast Fourier Transform (FFT) to extract the spectral energy in the wavelength range of 0.1 mm to 1 mm as the waviness spectral feature value. Next, the acquired acoustic emission signal feature value and waviness spectral feature value are subjected to max-min normalization. Finally, the calculated acoustic emission signal feature index and waviness spectral feature index, along with preset acoustic emission signal weights (e.g., determined empirically or experimentally), are used to... A value of 0.6 indicates that acoustic emission signals account for a significant proportion in stability assessment. (Imported into the formula) This calculation allows for the real-time acquisition of the stability coefficient of the current grinding process. For example, if the current grinding process is stable, and If they are all close to 0, then It will approach 1; if vibration or surface quality deterioration occurs during the grinding process, leading to and Increase, then This will be reduced accordingly, thus providing accurate stability feedback for subsequent coolant injection pressure adjustment.

[0045] Through the above technical solution, this application can quantify the stability of the bearing grinding process in real time and accurately. By comprehensively considering the acoustic emission signal and the ripple spectrum characteristic value, and performing normalization and weighted fusion, the obtained stability coefficient... It can comprehensively reflect the microscopic dynamics and macroscopic surface quality of the grinding process. This precise stability assessment makes the method for calculating the target coolant injection pressure more intelligent and adaptive. When signs of instability appear in the grinding process, the stability coefficient... The decrease in coolant pressure can be promptly fed back to the pressure regulation system, prompting more precise adjustments to the coolant injection pressure based on actual working conditions. This effectively suppresses grinding vibration, reduces surface defects, and prevents decreased machining quality or increased energy consumption due to insufficient or excessive cooling. Ultimately, this helps improve the machining accuracy, surface quality, and production efficiency of bearing grinding, while extending the service life of the grinding wheel and workpiece.

[0046] This application further proposes the following steps for calculating and obtaining the dynamic matching degree and direction sign of cooling supply-heat load:

[0047] The grinding process involves acquiring the energy coefficient, temperature coefficient, nozzle outlet flow rate, and nozzle-to-grinding point distance. The energy coefficient is a quantitative indicator of the energy state during grinding, reflecting the influence of factors such as grinding force, material removal rate, and specific grinding energy on heat generation. It can be obtained by real-time monitoring of grinding force, feed rate, and grinding power using sensors, calculating the material removal rate and specific grinding energy, normalizing these parameters, and then substituting them into a preset weighted formula for calculation; or by training grinding parameters using a machine learning model based on historical data or expert experience to predict the current energy coefficient. The temperature coefficient represents the contribution of the workpiece grinding zone temperature to the heat load. It can be obtained by real-time measurement of the workpiece grinding zone temperature using non-contact or contact sensors such as infrared thermometers or thermocouples, then substituting the measured values ​​into a preset temperature function model for calculation; or by predicting the grinding zone temperature based on finite element analysis or heat conduction models combined with grinding parameters, and calculating the temperature coefficient accordingly. The nozzle outlet flow rate refers to the volume or mass of coolant ejected from the nozzle per unit time. The coolant flow rate can be obtained by real-time monitoring of the coolant flow rate using a flow sensor (such as a turbine flow meter, electromagnetic flow meter, or ultrasonic flow meter) and calculating it in conjunction with the nozzle cross-sectional area; or by estimation based on the pump's set pressure and the nozzle's characteristic curve. The nozzle-to-grinding point distance refers to the spatial distance between the coolant nozzle outlet and the workpiece's grinding area. This distance can be obtained through real-time measurement or preset using a laser rangefinder, vision recognition system, or mechanical ruler; or by fixed setting or manual adjustment based on the grinding device's structural design and the nozzle's installation position.

[0048] The current nozzle outlet flow rate and the distance from the nozzle to the grinding point are both subjected to maximum-min normalization to obtain the flow rate index and distance index. Maximum-min normalization is a data preprocessing method that linearly transforms the original data to the [0,1] interval to eliminate the influence of dimensions and make data with different dimensions comparable. It is typically implemented by subtracting the minimum value of the dataset from each data point and then dividing by the difference between the maximum and minimum values ​​of the dataset. The flow rate index and distance index are the nozzle outlet flow rate and nozzle-to-grinding point distance values ​​after maximum-min normalization, respectively, reflecting the relative magnitude of the current flow rate and distance within the set range.

[0049] The comprehensive heat load index is obtained by weighted summation of the energy coefficient and temperature coefficient, where both the energy coefficient and temperature coefficient are proportional to the comprehensive heat load index. The specific calculation method is as follows: Input the energy coefficient and temperature coefficient into the formula... Obtain the comprehensive heat load index ,in, The energy-temperature balance weights are used to adjust the relative importance of energy and temperature factors in the total heat load. They can be adjusted according to different processing materials, grinding methods, or process requirements, or assigned values ​​through preset strategies or dynamic algorithms. Energy coefficient Temperature coefficient;

[0050] Import the comprehensive heat load index, flow rate index, and distance index into the formula. Obtain the dynamic matching degree of cooling supply and heat load. , , The larger the value, the more balanced the cooling supply and heat load demand are. The comprehensive heat load index, For traffic index, The distance index, To match tolerance, It is a positive real number used to adjust the cooling supply-heat load matching degree. For deviation The degree of sensitivity, The larger the value, the higher the system's tolerance for deviations between heat load and cooling capacity, and the better the matching degree. The rate of decrease slows down as the deviation increases; The smaller the value, the higher the system's requirement for matching accuracy; even a slight deviation will lead to... Significantly reduced, The value can be calibrated through process experiments: it is recommended to set the initial value to 0.1~0.3, and fine-tune it according to whether frequent pressure oscillations or sluggish response occur during the actual grinding process. This matching degree is quantified by a Gaussian function, the core idea of ​​which is to evaluate the actual heat load. Cooling supply capacity determined by coolant flow rate and spray distance The deviation between them. When the two are close, the matching degree A value close to 1 indicates a high degree of balance between cooling supply and heat load demand; conversely, a value close to 1 indicates a low degree of balance. The smaller the value, the greater the deviation.

[0051] The comprehensive heat load index, flow rate index, and distance index are substituted into the direction sign calculation function to obtain the direction sign. The direction sign calculation function determines the sign based on the difference between the comprehensive heat load index and the combination of the flow rate index and distance index; a positive sign is taken when the difference is positive, a negative sign when it is negative, and zero when it is zero. Specifically, the calculation method involves importing the comprehensive heat load index, flow rate index, and distance index into the formula... Obtain the direction symbol ,when hour, Take +1, when hour, Take -1, when hour, Take 0, where, The comprehensive heat load index, For traffic index, This is the distance index.

[0052] As a specific implementation method, the dynamic matching degree of cooling supply and heat load can be calculated during the bearing grinding process using the following method. and direction symbols First, the temperature of the workpiece grinding zone is acquired in real time using an infrared thermometer installed in the grinding area. Combined with data from the grinding force sensor, feed rate sensor, and grinding power sensor, the energy coefficient is calculated. and temperature coefficient Simultaneously, a flow sensor installed on the curved cooling water pipe 9 monitors the nozzle outlet flow rate in real time, and a laser rangefinder measures the distance from the nozzle 10 to the grinding point. This raw data is then fed into a data processing module for max-min normalization to generate a flow index. and distance index Next, the calculated energy coefficient will be processed in a controller or computing unit. and temperature coefficient Substitute into the formula Calculate the comprehensive heat load index Among them, the energy-temperature balance weight The thermal conductivity of the bearing material and the sensitivity of the grinding process can be preset to 0.6. Then, the comprehensive thermal load index is... Traffic Index and distance index Substitute into the formula The dynamic matching degree of cooling supply and heat load was calculated. Among them, parameters This can be set based on actual process experience, for example, 0.2. Finally, the comprehensive heat load index... Traffic Index and distance index Substitute into the formula The direction sign is calculated. These calculations, namely the dynamic matching degree of cooling supply and heat load, and direction symbols This will serve as a key input for subsequent calculations of the target coolant injection pressure.

[0053] The above technical solution precisely quantifies the dynamic matching relationship between heat load and cooling supply during the grinding process and clearly indicates the adjustment direction of coolant injection pressure. This solution comprehensively considers the energy state of the grinding process, workpiece temperature, and actual coolant supply parameters, transforming these complex factors into operable matching degrees and directional signs through a scientific mathematical model. This makes adaptive control of coolant injection pressure possible, avoiding the problems of insufficient cooling leading to workpiece burning and decreased surface quality, or excessive cooling causing resource waste and reduced processing efficiency, which are common in traditional cooling methods. Therefore, it effectively improves the processing quality and production efficiency of bearing grinding, and extends the service life of grinding tools and workpieces.

[0054] This application further proposes the following steps for calculating and obtaining the energy coefficient:

[0055] The system acquires the current grinding force, feed rate, and grinding power. Grinding force is the force exerted by the grinding wheel on the workpiece during grinding, reflecting the intensity of grinding and energy consumption. It can be obtained in real-time by force sensors installed on the grinding equipment, such as piezoelectric force sensors or strain gauge force sensors, converting the force signal into an electrical signal for acquisition and processing. Feed rate refers to the relative speed of the grinding wheel or workpiece during grinding, directly affecting the material removal rate. It can be obtained by real-time monitoring of the machine tool's feed axis speed using displacement sensors such as encoders and linear encoders. Grinding power refers to the rate of energy consumption during grinding, reflecting the energy input of the grinding process. It can be obtained by monitoring the current and voltage of the grinding spindle motor and calculating it in conjunction with motor efficiency, or by direct measurement using a power sensor.

[0056] The material removal rate is obtained by multiplying the current grinding force and feed rate. The material removal rate refers to the volume or mass of material removed from the workpiece surface per unit time and is a key indicator of grinding efficiency. This method is based on the principle that grinding force and feed rate are correlated with the amount of material removed under certain conditions. For example, in some grinding models, the material removal rate can be approximated as a function of grinding force and feed rate.

[0057] The specific grinding energy is obtained by comparing the current grinding power with the material removal rate. Specific grinding energy refers to the energy required to remove a unit volume of material, reflecting the energy efficiency of the grinding process. This ratio is the definition of specific grinding energy, i.e., the energy required to remove a unit volume of material. Through this calculation, the energy efficiency of the grinding process can be quantified.

[0058] The current grinding force, material removal rate, and specific grinding energy are all subjected to maximum-min normalization to obtain the grinding force index, material removal rate index, and specific grinding energy index. Maximum-min normalization transforms data with different dimensions or numerical ranges into a unified interval (e.g., 0 to 1 or -1 to 1) to facilitate comparison and integration between different characteristics. Maximum-min normalization is typically achieved by subtracting the minimum value from the data and then dividing by the difference between the maximum and minimum values. This method eliminates the influence of dimensions, ensuring that all indicators have equal weight or comparability in subsequent calculations.

[0059] The grinding force index, material removal rate index, and specific grinding energy index are substituted into the energy coefficient calculation function to obtain the energy coefficient. The energy coefficient calculation function is a weighted sum of the grinding force index, material removal rate index, and specific grinding energy index, where the specific grinding energy index participates in the calculation in a complementary manner. The energy coefficient ranges from 0 to 1; a higher energy coefficient indicates a higher energy state in the grinding process and a greater cooling requirement. Specifically, the grinding force index, material removal rate index, and specific grinding energy index are imported into the formula... Obtain the energy coefficient Energy coefficient Value range 0-1, energy coefficient A larger value indicates a higher energy state during the grinding process, resulting in more heat generation and greater cooling requirements. , and All are weighting coefficients with values ​​ranging from 0 to 1, and , , and This is used to adjust the relative importance of different indicators in the calculation of energy coefficient. By setting different weights, the sensitivity of the energy coefficient to various influencing factors can be flexibly adjusted according to the actual grinding process and material properties. For example, these weight coefficients can be determined through expert experience, experimental data analysis or optimization algorithms. The grinding force index, The material removal rate index. The grinding energy index is a weighted average that combines the grinding force index, material removal rate index, and grinding energy index. The grinding force index and material removal rate index are typically positively correlated with energy consumption, while the grinding energy index (after subtraction from 1) also reflects energy efficiency. Together, these three factors characterize the energy properties of the grinding process.

[0060] As a specific implementation method, the energy coefficient can be calculated through the following steps during the bearing grinding process. First, sensors are installed on the grinding device. For example, a force sensor is installed on bracket 2 to obtain the current grinding force in real time, an encoder is installed on the feed mechanism to obtain the feed speed, and the grinding power is estimated by monitoring the current and voltage of motor 3. Assume that at a certain moment, the current grinding force is measured to be F, the feed speed is v, and the grinding power is P. The material removal rate (MRR) can be calculated by multiplying the grinding force F by the feed speed v, F*v. Specific grinding energy... The grinding power P is then calculated using the ratio P / MRR of the material removal rate MRR. Next, the obtained grinding force F, material removal rate MRR, and specific grinding energy are analyzed. Perform max-min normalization. Finally, import these exponents into the formula. For example, the weighting coefficient can be set based on experience or experimental data. 0.4, for =0.3, The value is 0.3. This calculation yields the energy coefficient under the current grinding condition. .

[0061] Through the above technical solution, this application can accurately calculate the energy coefficient by comprehensively considering multiple key parameters such as grinding force, material removal rate, and specific grinding energy. This multi-dimensional and refined energy assessment method overcomes the limitations of relying on a single parameter or rough estimation of the energy coefficient, enabling the energy coefficient to more accurately reflect the actual heat load and cooling requirements during the grinding process. When this accurate energy coefficient is combined with the temperature coefficient for subsequent calculation of the dynamic matching degree of cooling supply and heat load, it can significantly improve the accuracy of coolant injection pressure adjustment, ensuring a high degree of matching between the coolant supply and injection method and the actual heat generation in the grinding zone. This not only effectively avoids problems such as workpiece burning and surface quality degradation caused by insufficient cooling, but also prevents resource waste caused by over-cooling, thereby significantly improving the processing quality, efficiency, and stability of bearing grinding, and helping to extend the service life of grinding tools and workpieces.

[0062] This application further proposes the following steps for calculating and obtaining the temperature coefficient:

[0063] Obtaining the temperature of the workpiece's grinding zone is crucial; this temperature is one of the most direct indicators of the grinding heat load, and its accuracy directly affects the precision of subsequent temperature coefficient calculations. One approach is to use non-contact infrared thermometry, scanning or measuring the grinding area with an infrared sensor or thermal imager to obtain the surface temperature distribution or temperature values ​​at specific points. Another approach is to use contact thermometry, such as embedding miniature thermocouples or resistance temperature sensors at specific locations on the workpiece or fixture to directly measure the temperature near the grinding zone. Furthermore, the temperature of the workpiece's grinding zone can be indirectly estimated by establishing a thermodynamic model of the grinding process and combining parameters such as grinding power, feed rate, and coolant flow rate.

[0064] The temperature of the workpiece grinding zone is substituted into the temperature coefficient calculation function to obtain the temperature coefficient. The temperature coefficient calculation function is as follows: based on the relationship between the workpiece grinding zone temperature and the preset optimal processing temperature and maximum safe temperature, the temperature coefficient is calculated piecewise. When the temperature does not exceed the optimal processing temperature, the temperature coefficient is 0; when the temperature exceeds the optimal processing temperature but does not exceed the maximum safe temperature, the temperature coefficient is calculated using an exponential function, where the exponent is the square of the standardized deviation of the temperature relative to the optimal processing temperature; when the temperature exceeds the maximum safe temperature, the temperature coefficient is 1. The temperature coefficient ranges from 0 to 1. A larger temperature coefficient indicates a higher heat load and a greater cooling demand. Specifically, the workpiece grinding zone temperature is imported into the formula... Obtain the temperature coefficient , Temperature coefficient A larger value indicates a higher heat load and a greater cooling requirement. Temperature sensitivity coefficient The steepness of the temperature coefficient's growth curve within the "temperature rise range" is determined, and can be assigned values ​​through preset strategies or dynamic algorithms; Temperature in the workpiece grinding zone. To achieve the optimal processing temperature, This is the highest safe temperature allowed by the process.

[0065] This application's solution significantly improves the accuracy and responsiveness of dynamic adjustment of coolant injection pressure by introducing precise quantification of the workpiece grinding zone temperature. Its operating mechanism involves firstly, directly capturing the heat information generated during the grinding process by real-time monitoring or estimation of the workpiece grinding zone temperature. Subsequently, this temperature data is input into a carefully designed nonlinear piecewise function to calculate the temperature coefficient. This function cleverly divides the temperature state into three intervals: when the temperature is at its optimal or lower level, the temperature coefficient... A value set to zero indicates a low current heat load and minimal cooling demand; as the temperature gradually increases and enters the medium heat load range, the temperature coefficient... The temperature sensitivity coefficient accurately reflects the cumulative heat load and the growth trend of cooling demand through a smooth and gradual increase via an exponential function. The system allows adjustments to its response sensitivity to temperature changes based on specific process requirements; once the temperature exceeds the maximum safety threshold allowed by the process, the temperature coefficient... This is then set to the maximum value of 1, indicating that the heat load has reached a critical state and maximum cooling intensity is required. This method of calculating the temperature coefficient based on actual temperature measurement and nonlinear mapping makes the temperature coefficient... It can accurately and sensitively quantify the thermal load in the workpiece's grinding zone and standardize it to a value between 0 and 1. This standardized temperature coefficient... It was then effectively integrated into the aforementioned calculation of the comprehensive heat load index. In the formula, with energy coefficient Together, these constitute a comprehensive assessment of the grinding heat load. In this way, the proposed solution overcomes the problems of insufficient or delayed heat load assessment in traditional cooling control, ensuring a dynamic match between cooling supply and heat load. The calculations are more accurate, thereby increasing the target coolant injection pressure. The adjustments enable a more timely and effective response to changes in thermal load during the grinding process. This not only helps prevent workpiece burns, surface quality degradation, or increased residual stress caused by overheating, but also avoids unnecessary resource waste by optimizing the use of coolant, thereby comprehensively improving the processing quality, efficiency, and stability of bearing grinding.

[0066] The following is a specific example to illustrate this. In bearing grinding operations, an infrared thermal imager installed near the grinding table 1 can be used to continuously monitor the surface temperature of the contact area between the bearing and the grinding wheel 4, i.e., the temperature of the workpiece grinding zone. Assuming the optimal machining temperature is set based on the bearing material and grinding process requirements. The maximum safe temperature allowed by the process is 35℃. The temperature is 75℃, and the temperature sensitivity coefficient is... It is configured to 2.5. When the infrared thermal imager detects the temperature of the workpiece grinding zone... At 30℃, because this temperature is lower than or equal to The system will use the temperature coefficient The calculation result is 0. This means that the current heat load is ideal, and no additional cooling intervention is required. As the grinding process continues, the temperature in the workpiece grinding zone... As the temperature gradually rises to 60℃, the temperature is between and Between. The system will Substituting into the formula yields a temperature coefficient between 0 and 1. A value, for example, 0.7. This value reflects a significant increase in the current heat load, requiring corresponding cooling support. Under certain extreme grinding conditions, the temperature in the workpiece grinding zone... It surged further to 85°C, at which point the temperature had exceeded [a certain threshold]. The system will use the temperature coefficient. Set directly to 1. This indicates that the heat load has reached its maximum level, requiring immediate and intensive cooling measures. These are the temperature coefficients calculated in real time. It is then transmitted to the control unit, along with the energy coefficient. Together with other parameters, it is used to accurately calculate the comprehensive heat load index. This, in turn, affects the dynamic matching degree of cooling supply and heat load. and direction symbols The determination of this factor ultimately guides the precise adjustment of the coolant injection pressure, ensuring the stability of the grinding process and the quality of the workpiece.

[0067] The above technical solution provides a precise, dynamic, and adaptive method for calculating the temperature coefficient, effectively solving the problem of accurately quantifying the grinding heat load during bearing grinding. This method can standardize the heat load level into a temperature coefficient using a nonlinear function based on the actual temperature of the workpiece's grinding zone. This allows for more accurate calculations of the dynamic matching degree between cooling supply and heat load, enabling precise and adaptive adjustment of coolant injection pressure. Compared to traditional cooling strategies that rely on experience or fixed parameters, this solution can respond more sensitively to heat changes during grinding, effectively avoiding workpiece burning, surface quality degradation, or increased residual stress due to insufficient cooling, while also avoiding resource waste caused by over-cooling. This is achieved by introducing an optimal processing temperature. and maximum safe temperature The concept, combined with the temperature sensitivity coefficient By employing nonlinear mapping, this solution ensures that the cooling system provides appropriate cooling intensity under different thermal load conditions, thereby significantly improving the processing quality and efficiency of bearing grinding and extending the service life of the grinding wheel and workpiece.

[0068] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A grinding method for bearing processing, characterized in that, Includes the following steps: The energy coefficient is calculated based on grinding force, material removal rate, and specific grinding energy. The temperature coefficient is calculated based on the temperature of the workpiece grinding zone. Based on the nozzle outlet flow rate and nozzle-to-grinding point distance under energy and temperature coefficients, the dynamic matching degree and direction sign of cooling supply-heat load are calculated and obtained. The stability coefficient is calculated based on the acoustic emission signal characteristic value and the ripple spectrum characteristic value. Based on the base pressure, the dynamic matching degree of cooling supply and heat load, the direction sign and the stability coefficient, the target coolant injection pressure is calculated and obtained, and the current coolant injection pressure is adjusted to the target coolant injection pressure; The steps for calculating and obtaining the dynamic matching degree and direction sign of cooling supply-heat load are as follows: Obtain the energy coefficient, temperature coefficient, nozzle outlet flow rate, and nozzle-to-grinding point distance; The current nozzle outlet flow rate and the distance from the nozzle to the grinding point are both subjected to maximum-min normalization to obtain the flow rate index and the distance index. The energy coefficient and temperature coefficient are weighted and summed to obtain the comprehensive heat load index, where both the energy coefficient and temperature coefficient are proportional to the comprehensive heat load index. Import the comprehensive heat load index, flow rate index, and distance index into the formula. Obtain the dynamic matching degree of cooling supply and heat load. , , The larger the value, the more balanced the cooling supply and heat load demand are. The comprehensive heat load index, For traffic index, The distance index; The heat load composite index, flow rate index, and distance index are substituted into the direction sign calculation function to obtain the direction sign. The direction sign calculation function is as follows: the sign is determined based on the difference between the heat load composite index and the combination of the flow rate index and the distance index. When the difference is positive, a positive sign is taken; when it is negative, a negative sign is taken; and when it is zero, a zero sign is taken. The steps for calculating and obtaining the stability coefficient are as follows: Acquire the acoustic emission signal characteristic values ​​and workpiece surface waviness spectrum characteristic values ​​during the grinding process; The current acoustic emission signal feature value and waviness spectrum feature value are processed by maximum-minimum normalization to obtain the acoustic emission signal feature index and waviness spectrum feature index. The stability coefficient is obtained by performing a negative exponential transformation on the weighted sum of the acoustic emission signal characteristic index and the ripple spectrum characteristic index; the stability coefficient ranges from 0 to 1, and the larger the stability coefficient, the more stable the processing. The step of calculating and obtaining the target coolant injection pressure is as follows: Obtain the base pressure, cooling supply-heat load dynamic matching degree, direction sign, and stability coefficient; Import the base pressure, cooling supply-heat load dynamic matching degree, direction sign, and stability coefficient into the formula. Obtain the target coolant injection pressure ,in, Based on pressure, Adjust the gain coefficient for pressure. For direction symbols, To achieve dynamic matching of cooling supply and heat load, This is the stability coefficient.

2. The grinding method for bearing processing according to claim 1, characterized in that, The steps for calculating and obtaining the energy coefficient are as follows: Obtain the current grinding force, material removal rate, and specific grinding energy; The current grinding force, material removal rate, and specific grinding energy are all subjected to maximum-min normalization to obtain the grinding force index, material removal rate index, and specific grinding energy index. The grinding force index, material removal rate index, and specific grinding energy index are substituted into the energy coefficient calculation function to obtain the energy coefficient. The energy coefficient calculation function is a weighted sum of the grinding force index, material removal rate index, and specific grinding energy index, wherein the specific grinding energy index participates in the calculation in a complementary manner. The energy coefficient ranges from 0 to 1. The larger the energy coefficient, the higher the energy state of the grinding process and the greater the cooling requirement.

3. The grinding method for bearing processing according to claim 2, characterized in that, The material removal rate and specific grinding energy are obtained as follows: Obtain the current grinding force, feed rate, and grinding power; The material removal rate is obtained by multiplying the current grinding force and feed rate. The specific grinding energy is obtained by processing the ratio of the current grinding power to the material removal rate.

4. The grinding method for bearing processing according to claim 1, characterized in that, The steps for calculating and obtaining the temperature coefficient are as follows: Obtain the temperature of the workpiece grinding zone; The temperature of the workpiece grinding zone is substituted into the temperature coefficient calculation function to obtain the temperature coefficient. The temperature coefficient calculation function is: based on the relationship between the workpiece grinding zone temperature and the preset optimal processing temperature and the maximum safe temperature, the temperature coefficient is calculated in segments. When the temperature does not exceed the optimal processing temperature, the temperature coefficient is 0. When the temperature exceeds the optimal processing temperature but does not exceed the maximum safe temperature, the temperature coefficient is calculated using an exponential function, the exponent of which is the square of the standardized deviation of the temperature relative to the optimal processing temperature. When the temperature exceeds the maximum safe temperature, the temperature coefficient is 1. The temperature coefficient ranges from 0 to 1. The larger the temperature coefficient, the higher the heat load and the greater the cooling demand.

Images