Automatic finishing method for surface of planetary reducer planetary carrier

Abstract

The application relates to the technical field of planet carrier processing, in particular to a surface automatic finishing processing method of a planet carrier of a planet reducer, which comprises the following steps: dividing a current planet carrier processing process into multiple monitoring periods; in any monitoring period, differences between each processing parameter and grinding pressure at all times, differences between each processing parameter and grinding pressure and preset rated values and discrete degrees of the differences are analyzed to determine a response coefficient; based on the differences between each processing parameter characteristic coefficient between any monitoring period and all monitoring periods before the any monitoring period and distribution differences of each processing parameter, and in combination with the response coefficient, a regulation coefficient is determined to regulate each processing parameter in the next monitoring period. The application improves the processing precision of the planet carrier by regulating the processing parameters in real time.

Description

Technical Field

[0001] This application relates to the field of planetary carrier processing technology, specifically to an automated surface finishing method for planetary carriers of planetary gearboxes. Background Technology

[0002] Planetary gear reducers are high-precision transmission devices composed of a sun gear, planet gears, a planet carrier, and an internal gear ring. Among them, the planet carrier is the core load-bearing component of the entire transmission system, and its machining quality directly determines the transmission accuracy and service life of the reducer. It must not only withstand the huge torque generated by the revolution of the planet gears, but also ensure extremely high coaxiality of the shaft holes of each planet gear to meet the dual stringent requirements of high strength and high precision.

[0003] Finishing is a crucial step in improving the surface quality and precision of planetary carriers. However, due to the differences in the initial state of different batches of workpieces, the pressure fluctuations during grinding are extremely significant, posing a severe challenge to the precise control of key parameters such as grinding wheel speed and feed rate. The fundamental flaw of traditional control methods lies in their failure to fully consider the dynamic impact of individual differences in workpiece surface roughness on the control response. This results in a slow response of the system to drastic changes in grinding pressure, making it difficult to effectively suppress machining errors and reducing the machining accuracy of the planetary carrier. Summary of the Invention

[0004] To address the aforementioned technical problems, this application provides an automated finishing method for the surface of the planetary carrier of a planetary gearbox, thereby resolving the existing issues.

[0005] The automated surface finishing method for the planetary carrier of the planetary gear reducer in this application adopts the following technical solution:

[0006] One embodiment of this application provides an automated surface finishing method for the planetary carrier of a planetary gear reducer, the method comprising the following steps:

[0007] Real-time acquisition of grinding pressure and all processing parameters of the processing equipment during the processing of the current planetary carrier and all previous planetary carriers in the same batch, including rotational speed and feed rate;

[0008] Based on the distribution of time intervals between all adjacent extreme values ​​of grinding pressure during the processing of each planetary carrier, the time characteristic value of each planetary carrier is determined; based on the dispersion of all grinding pressures during the processing of each planetary carrier, the characteristic weight of each planetary carrier is determined, and combined with the time characteristic value, the current planetary carrier processing is divided into multiple monitoring cycles.

[0009] Within any monitoring period, by analyzing the differences between each processing parameter and grinding pressure at all times, as well as the differences between each processing parameter and grinding pressure and their preset rated values, the characteristic coefficients of each processing parameter in any monitoring period are determined. Combined with the dispersion of the differences between each processing parameter and the preset rated values ​​at all times within any monitoring period, the response coefficients of each processing parameter in any monitoring period are determined. Based on the differences in the characteristic coefficients of each processing parameter between any monitoring period and all previous monitoring periods, as well as the distribution differences of each processing parameter, the weight parameters of each processing parameter in any monitoring period are determined. Combined with the response coefficients, the characteristic values ​​of each processing parameter in any monitoring period are determined.

[0010] Based on the characteristic values ​​of each processing parameter in the current monitoring cycle, the control coefficient of each processing parameter in the next monitoring cycle is determined so as to control each processing parameter in the next monitoring cycle.

[0011] Preferably, the time characteristic value of each planetary carrier is the average of the time intervals between all adjacent extreme values ​​of all grinding pressures during the processing of each planetary carrier.

[0012] Preferably, the characteristic weight of each planetary carrier is the result of normalizing the standard deviation of all grinding pressures during the processing of each planetary carrier.

[0013] Preferably, the process of dividing the current planetary carrier manufacturing process into multiple monitoring cycles includes:

[0014] Calculate the product of the time characteristic value and the characteristic weight of each planetary support, and take the average of the product of the time characteristic value and the characteristic weight of all planetary supports in the same batch before the current planetary support as the length of the monitoring period.

[0015] For the current planetary carrier manufacturing process, the time period from the start of the manufacturing process to the current time is divided into multiple monitoring cycles according to the length of the monitoring cycle.

[0016] Preferably, the method for determining the characteristic coefficients of each processing parameter in any monitoring cycle is as follows:

[0017] Within any monitoring period, the difference between each processing parameter and grinding pressure and its preset rated value at each time point is calculated and then divided by the preset rated value. These results are recorded as the state deviation values ​​of each processing parameter and grinding pressure at each time point. The mean, variance, and range of the state deviation values ​​of each processing parameter and grinding pressure at all times are used to form their respective state sequences.

[0018] Calculate the comprehensive difference between the state sequence of each processing parameter and grinding pressure at all times within any monitoring period, and use the result of positively fusing the difference between each processing parameter and grinding pressure at all times within any monitoring period with the corresponding comprehensive difference as the characteristic coefficient of each processing parameter in any monitoring period.

[0019] Preferably, the response coefficient of each processing parameter in any monitoring period is the product of the dispersion of each processing parameter at all times in any monitoring period and the characteristic coefficient.

[0020] Preferably, the expression for the weight parameter of each processing parameter in any monitoring period is: In the formula, The weight parameter represents the a-th processing parameter under monitoring period x; , These represent the characteristic coefficients of the a-th processing parameter under monitoring period x and under monitoring period v before monitoring period x, respectively. This represents the difference in the state sequence of the a-th processing parameter between monitoring period x and its previous monitoring period v; This indicates the number of all monitoring cycles between the start time of the current planetary carrier manufacturing process and the start time of monitoring cycle x.

[0021] Preferably, the characteristic value of each processing parameter in any monitoring period is the result of positive fusion of the response coefficient and weight parameter of each processing parameter in any monitoring period.

[0022] Preferably, the expression for the control coefficient of each processing parameter in the next monitoring cycle is: In the formula, This represents the control coefficient for the a-th processing parameter in the next monitoring cycle following the current monitoring cycle; This represents the reference value of the proportional gain obtained by the attenuation curve method; This represents the normalized value of the characteristic value of the a-th processing parameter in the next monitoring cycle after the current monitoring cycle.

[0023] Preferably, the adjustment of each processing parameter in the next monitoring cycle includes:

[0024] In the next monitoring cycle after the current monitoring cycle, the difference between each processing parameter and the preset rated value at each time point is used as the input of the PID controller. The control coefficient of each processing parameter in the next monitoring cycle is used as the value of the proportional gain in the PID controller, and the control signal of each processing parameter is output to regulate each processing parameter.

[0025] This application has at least the following beneficial effects:

[0026] This application quantifies the fluctuation period and intensity of grinding pressure to dynamically determine a personalized monitoring cycle for each planetary carrier. This method effectively solves the problem of lag in traditional control response caused by workpiece surface unevenness. By shortening the monitoring interval for workpieces with drastic changes in state and extending the monitoring cycle for workpieces with stable state, the precise allocation of control resources is improved. Furthermore, within each monitoring cycle, this application calculates characteristic values ​​to determine the priority intervention level of the controller by integrating the current control performance, fluctuation risk, and historical deviation of the machining parameters. This enables the controller to accurately identify and prioritize the handling of the most critical parameter deviations, thereby effectively suppressing dynamic disturbances caused by workpiece surface unevenness and ensuring high stability and high precision in the planetary carrier machining process. This application analyzes multidimensional data in real time during the machining process to dynamically generate characteristic values ​​to quantify the necessity and weight of regulation. Based on this, the core gain parameters of the PID controller are adaptively adjusted. This method transforms traditional fixed parameter control into intelligent regulation based on real-time state feedback, enabling the controller to actively and accurately respond to dynamic disturbances caused by changes in workpiece surface roughness, thereby improving the machining accuracy of the planetary carrier. Attached Figure Description

[0027] To more clearly illustrate the technical solutions and advantages in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a flowchart illustrating the steps of an automated surface finishing parameter adjustment method for a planetary gearbox planetary carrier provided in one embodiment of this application.

[0029] Figure 2 This is a schematic diagram of a feature value extraction process provided in one embodiment of this application. Detailed Implementation

[0030] To further illustrate the technical means and effects adopted by this application to achieve the intended purpose of the invention, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of the automated surface finishing method for the planetary carrier of a planetary gear reducer proposed in this application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0032] The following description, in conjunction with the accompanying drawings, details the specific scheme of the automated surface finishing method for the planetary gearbox planetary carrier provided in this application.

[0033] One embodiment of this application provides an automated surface finishing method for the planetary carrier of a planetary gear reducer, the method comprising the following steps:

[0034] The boring method for the planetary carrier of the planetary reducer proposed in this embodiment achieves precise control over the boring process of the planetary carrier, improves the accuracy of the boring process, and thus improves the manufacturing accuracy of the planetary reducer. The specific machining control process is as follows:

[0035] S1: Raw material preparation and rough machining.

[0036] (1) Raw material pretreatment

[0037] 40Cr forged steel is selected as the blank. The blank is forged into a disc shape by die forging or free forging. The initial temperature during forging is controlled at 1100℃ and the final forging temperature is ≥800℃ to avoid coarse grains and forging cracks during forging. After forging, normalizing treatment is performed at 850℃ for 2 hours. After normalizing treatment, air cooling is performed to homogenize the material structure and control the hardness at HB180.

[0038] (2) Rough machining and forming

[0039] The end faces of the pre-treated blank material are machined using a CNC machine tool to ensure a 5mm machining allowance in the thickness direction. After the end faces are machined, the outer diameter is machined to remove the oxide scale and make the outer diameter 8mm larger than the finished product. After the outer diameter is machined, a center bottom hole is drilled to make the center bottom hole 10mm smaller than the center shaft hole of the finished product.

[0040] (3) Stress relief treatment and datum positioning

[0041] After rough machining, the material is placed in a 200℃ environment for 4 hours to release the internal stress generated during cutting and prevent workpiece deformation during finish machining. After the heat treatment, a dial indicator is used to check the coaxiality of the outer circle and the center bottom hole of the material. The coaxiality after rough machining must be controlled within 0.1mm.

[0042] S2: Semi-finish turning and boring.

[0043] (1) Semi-finishing

[0044] The workpiece is semi-finished using a CNC machine tool (e.g., a CK6150 CNC machine tool). Specifically, the outer diameter and cross-section of the rough-turned structure are used as positioning references. The workpiece is clamped using a combination of a three-jaw chuck and an end face center to ensure that the radial runout of the workpiece is ≤0.1mm. The cutting process is carried out using a carbide-coated guide, with a boring speed of 80m / min, a feed rate of 0.2mm / r, and a depth of cut of 1mm. During the machining process, the machining parameters are monitored and controlled in real time by a PLC control system to achieve stable control of the machining process.

[0045] (2) Boring

[0046] The workpiece after semi-finish turning is processed using a CNC boring machine (e.g., TK6513). Specifically, the end face and outer diameter of the semi-finish turned workpiece are used as references, and positioning is achieved through a "one face, two pins" method. A pressure plate is used to evenly clamp the workpiece, ensuring the coaxiality between the workpiece and the machine spindle is ≤0.05mm. High-speed boring is then used for boring. In this embodiment, the boring speed is 60m / min, the feed rate is 0.15mm / r, and the depth of cut is 2mm. Multi-hole machining is performed in the order of center hole – pin hole. After each boring operation, chips are blown away with an air gun. This ensures that the roundness error of the hole after rough boring is within 0.03mm, and the hole diameter is 3mm larger than the target size for finish boring, leaving sufficient machining allowance for finish boring. Rough boring initially corrects the positional deviation of the hole, making the hole distribution accuracy controllable during subsequent finish boring.

[0047] After rough boring, the workpiece is precision boring using a high-precision CNC boring machine. Specifically, the support point of the planetary carrier is used as the clamping point, and an end face with an area ≥100cm² is selected as the positioning reference surface. The workpiece is clamped with a hydraulic clamping device at a pressure of 300N. Precision boring tools are used for precision boring. In this embodiment, the boring speed is 50m / min, the feed rate is 0.08mm / r, and the depth of cut is 0.1mm. Two finishing processes are performed. During the machining process, water-soluble cutting fluid with a concentration of 8% is sprayed at a pressure of 0.5MPa for cooling to avoid excessive temperature during machining. After precision boring, the cylindricity of the pin hole is ≤0.005mm, the coaxiality with the center hole is ≤0.01mm, and the hole diameter tolerance is controlled at IT7 grade to ensure that the hole system accuracy meets the assembly requirements of the subsequent planetary gear shaft and bearing, providing a stable reference for the precision turning process.

[0048] S3: Precision machining.

[0049] Precision turning is performed using a CNC machine tool with a positioning accuracy of ±0.003mm. In this application, an HTC3250n CNC machine tool can be used for this process. A TiAlN coated carbide tool is used for turning, with a cutting speed of 120m / min, a feed rate of 0.1mm / r, and a depth of cut of 0.2mm, to ensure a flatness of ≤0.1mm and leave a 0.3mm grinding allowance. After the end face is machined, a precision-ground internal turning tool is used to cut the center bottom hole, with a cutting speed of 80m / min and a feed rate of 0.08mm / r, in two cuts until the tolerance reaches IT7 grade. After the center bottom hole is machined, a CNMG120408 external turning tool is used to process the outer circle, with a turning speed of 150m / min, to ensure that the coaxiality between the outer circle and the center shaft hole is ≤0.01mm. During the precision turning process, multiple sensors are used to monitor the machining parameters and temperature in real time. Based on the monitoring results, a PLC control system is used for real-time control to avoid dimensional deviations due to heat accumulation during machining.

[0050] S4: Drilling process.

[0051] After finish turning, drilling was performed using a Fanucα-D21MiB CNC machining center and a precision indexing head. A high-speed steel twist drill, 2mm smaller than the finished hole diameter, was used for rough drilling at a speed of 800 rpm and a feed rate of 0.15 mm / r. After rough drilling, the bottom hole was machined in one pass using the indexing head to a depth 2mm deeper than the finished hole. Chips were then removed using 0.6 MPa high-pressure gas. Following this, a 3-flute reamer was used for enlarging the hole at a speed of 1200 rpm and a feed rate of... The feed rate is 0.12 mm / r, and the roundness of the bottom hole is corrected to ≤0.01 mm, with a 0.2 mm allowance for reaming. After the hole is enlarged, a CNC reamer with IT6 precision is used for reaming, and a floating reamer chuck is used to counteract spindle runout. The spindle speed is set to 300 r / min and the feed rate is 0.08 mm / r. During the machining process, the PLC control system is used for monitoring and control, and the temperature and machining parameters during the machining process are monitored and analyzed to accurately control the temperature and machining parameters during the drilling process.

[0052] S5: Finishing process.

[0053] Before finishing the workpiece after drilling, pretreatment is required, including deburring, precision cleaning, residual material inspection, and local correction. First, the workpiece is deburred using an ultrasonic cleaning machine with a 5% concentration of deburring solution, a cleaning temperature of 50℃, and a cleaning time of 10 minutes. After treatment, the workpiece is sprayed with an 8% alkaline degreasing agent at a pressure of 1.0MPa in an environment of 60℃ to remove oil stains. After spraying, it is rinsed in ultrapure water with a resistivity ≥15MΩ·cm to remove residues. After rinsing, the workpiece is dried with hot air at 80℃ until the moisture content is ≤0.1%.

[0054] After the above pretreatment, the bushing hole is honed using a CNC internal honing machine. The central shaft hole is honed using diamond honing strips with a grit size of #400. The spindle speed is set to 800 r / min, the honing head reciprocating speed is 100 mm / min, and the feed rate is 0.005 mm / r. At the same time, a 6% water-soluble honing fluid is sprayed for cooling and chip removal. The hole diameter is monitored online using a laser diameter gauge until the bushing hole reaches IT6 grade and the surface roughness Ra is 0.4 μm.

[0055] The end faces are ground using a CNC double-end face grinder. Positioning is based on the central shaft hole. A resin-bonded grinding wheel with a grit size of #600 is used for grinding. The grinding wheel linear speed is set to 30 m / s, the feed rate to 0.001 mm / r, and the grinding depth to 0.3 mm. Simultaneous grinding with two grinding wheels ensures that the parallelism of both end faces is ≤0.005 mm. Automated control is implemented during the finishing stage to ensure that the finished planetary carrier meets high-precision assembly and force transmission requirements. However, initial roughness deviations in the workpiece significantly affect the stability of the grinding pressure, leading to inaccurate control response of the machining parameters and consequently compromising the final machining accuracy. Therefore, this embodiment integrates data acquisition for real-time monitoring and analysis of the finishing process, dynamically optimizing the control strategy to effectively suppress machining disturbances caused by roughness fluctuations, thereby improving the finishing accuracy. The flowchart of the automated finishing parameter adjustment method for the planetary carrier surface of the planetary reducer provided in this embodiment is shown below. Figure 1 As shown, the specific process is as follows:

[0056] S5.1: Real-time acquisition of grinding pressure and all processing parameters of the processing equipment during the processing of the current planetary carrier and all previous planetary carriers in the same batch. Among them, all processing parameters include rotational speed and feed rate.

[0057] During the finishing process after the planetary carrier pretreatment, a multi-sensor device is used to collect all kinds of processing parameters and grinding pressure. All kinds of processing parameters include rotational speed and feed rate. In this embodiment, a rotational speed sensor is used to collect the rotational speed of the processing equipment during the planetary carrier processing, a displacement sensor is used to collect the feed rate of the processing equipment during the planetary carrier processing, and a force sensor is used to collect the grinding pressure during the planetary carrier processing. The above data collection is synchronous and real-time, and the collection frequency is f. The value of f is set manually. In this embodiment, the value of f is 500Hz. In actual application, as other implementation methods, the implementer can also set it according to the specific situation. This embodiment does not impose any special restrictions.

[0058] Furthermore, in order to eliminate the influence of noise, the collected data are filtered. In this embodiment, a Kalman filter is used to filter and reduce noise in the collected data. In practical applications, as other implementation methods, implementers may also use other filtering methods such as Gaussian filtering algorithm according to specific circumstances. This embodiment does not impose any special restrictions on the selection of filtering methods.

[0059] The process of using the Kalman filter algorithm to filter and reduce noise in the data is a well-known technique and will not be described in detail here.

[0060] Furthermore, in order to eliminate the influence of dimensions between data, this embodiment performs normalization processing on the collected data according to categories. In this embodiment, the maximum-minimum value normalization method is used to normalize the data. In actual application, as other implementation methods, implementers may also use other normalization methods such as z-score standardization according to specific circumstances. This embodiment does not impose any special restrictions.

[0061] The maximum-minimum normalization algorithm is a well-known technique, and the specific process of using it to normalize data will not be elaborated here.

[0062] S5.2: Based on the distribution of time intervals between all adjacent extreme values ​​of grinding pressure during the processing of each planetary carrier, determine the time characteristic value of each planetary carrier; based on the dispersion of all grinding pressures during the processing of each planetary carrier, determine the characteristic weight of each planetary carrier, and combine the time characteristic value to divide the current planetary carrier processing into multiple monitoring cycles.

[0063] During the surface finishing stage of the planetary carrier, although it has undergone pretreatment such as precision turning and drilling, local variations in surface condition due to previous processes are still unavoidable. These variations cause drastic fluctuations in grinding pressure during grinding, which in turn severely interferes with the precise control of grinding parameters (such as rotational speed and feed rate). Because traditional automated control is difficult to effectively respond to these dynamic disturbances caused by uneven workpiece surfaces, the grinding process ultimately deviates from the ideal trajectory, resulting in significant machining errors and ultimately compromising the final surface finish and quality of the planetary carrier.

[0064] Therefore, based on the above analysis, this embodiment determines the time characteristic value of each planetary carrier based on the distribution of the time interval between all adjacent extreme values ​​of grinding pressure during the processing of each planetary carrier; it determines the characteristic weight of each planetary carrier based on the dispersion of all grinding pressures during the processing of each planetary carrier, and combines the time characteristic value to divide the current planetary carrier processing into multiple monitoring cycles. The specific process is as follows:

[0065] First, this embodiment determines the time characteristic value of each planetary carrier based on the distribution of the time intervals between all adjacent extreme values ​​of grinding pressure during the machining process of each planetary carrier, specifically:

[0066] In this embodiment, the average of the time intervals between all adjacent extreme values ​​of grinding pressure during the processing of each planetary carrier is taken as the time characteristic value of each planetary carrier.

[0067] The method for obtaining the extreme values ​​is a well-known technique, and will not be described in detail in this embodiment.

[0068] Based on the time characteristic values ​​of each planetary carrier, it can be understood that the time characteristic value reflects the cycle of grinding state changes caused by uneven surface roughness of the planetary carrier. It is used to characterize the time scale of grinding state changes. If the time characteristic value of the planetary carrier is larger, it indicates that the wear state change cycle of the planetary carrier is longer, that is, the grinding pressure will only fluctuate significantly once in a long period of time. This indicates that the surface state of the planetary carrier is relatively uniform. Therefore, a longer monitoring period can be used without missing key state changes. Conversely, if the time characteristic value is smaller, it indicates that the grinding state change cycle is shorter, and the grinding pressure exhibits frequent and violent fluctuations. This directly reflects that the surface roughness of the planetary carrier is significantly different, with many local high points or depressions. In this case, the monitoring period must be shortened to capture and respond to these rapid changes in time. Otherwise, the machining quality will decrease or even the planetary carrier will be damaged due to control lag.

[0069] Furthermore, this embodiment determines the characteristic weights of each planetary carrier based on the dispersion of all grinding pressures during the machining process of each planetary carrier, specifically as follows:

[0070] In this embodiment, the result of normalizing the standard deviation of all grinding pressures during the processing of each planetary carrier is used as the feature weight of each planetary carrier.

[0071] Based on the characteristic weights of each planetary carrier, it can be understood that the characteristic weights reflect the importance of the planetary carrier in determining the monitoring cycle division during the entire batch of planetary carrier processing. They are used to characterize the degree of influence of the instability of the planetary carrier grinding process on the overall control strategy. If the characteristic weight is larger, it indicates that the standard deviation of the grinding pressure of the planetary carrier accounts for a high proportion in the entire batch, that is, the grinding process fluctuates the most violently, which reflects that there may be abnormal surface defects on the surface of the planetary carrier. Conversely, if the characteristic weight is smaller, it indicates that the standard deviation of the grinding pressure of the planetary carrier accounts for a low proportion in the entire batch, and its grinding process is relatively stable with little fluctuation. This reflects that the surface condition of the planetary carrier is uniform and its processing performance is good. Therefore, its influence is small when formulating the overall control strategy, and the same more universal monitoring cycle as most other workpieces can be adopted, thereby simplifying the control logic and improving the overall processing efficiency.

[0072] Furthermore, this embodiment divides the current planetary carrier processing into multiple monitoring cycles based on the feature weights of each planetary carrier and in conjunction with the time feature values. Specifically:

[0073] In this embodiment, the result of multiplying the time feature value and feature weight of each planetary support is calculated, and the average of the multiplication results of all planetary supports in the same batch before the current planetary support is used as the length of the monitoring period.

[0074] For the current planetary carrier manufacturing process, the time period from the start of the manufacturing process to the current time is divided into multiple monitoring cycles according to the length of the monitoring cycle.

[0075] Based on the length of the monitoring cycle, it can be understood that the monitoring cycle reflects the comprehensive practical characteristics of the grinding state changes of the same batch of workpieces. If the time characteristic value of the planetary carrier is larger, it indicates that the state of the processing equipment changes slowly during the planetary carrier processing, that is, the grinding state changes relatively smoothly, and the monitoring cycle tends to be increased. In addition, if the characteristic weight is smaller, it indicates that the grinding process fluctuates smoothly, indicating that the surface of the planetary carrier is relatively fine. Therefore, the monitoring cycle can be increased to improve the overall processing efficiency of the planetary carrier.

[0076] Conversely, the smaller the time characteristic value of the planetary carrier, the shorter the grinding state change cycle and the more frequent the process. This requires shortening the monitoring cycle in order to closely track its dynamic changes. At the same time, the larger the characteristic weight, the more drastic the fluctuation of the grinding process of the planetary carrier, and the more abnormal defects may exist on the surface. Therefore, it is even more necessary to shorten the monitoring cycle and increase the monitoring frequency to ensure that the controller can respond in time and effectively suppress such drastic fluctuations, thereby ensuring the final processing quality.

[0077] Thus, this embodiment quantifies the fluctuation period and intensity of grinding pressure to dynamically determine a personalized monitoring cycle for each planetary carrier. This method effectively solves the problem of traditional control response lag caused by uneven workpiece surface. By shortening the monitoring interval for workpieces with drastic changes in state and extending the monitoring cycle for workpieces with stable state, the precise allocation of control resources is improved.

[0078] S5.3: Within any monitoring period, by analyzing the differences between each processing parameter and grinding pressure at all times, and the differences between each processing parameter and grinding pressure and their preset rated values, the characteristic coefficient of each processing parameter in any monitoring period is determined. Combined with the dispersion of the differences between each processing parameter and the preset rated values ​​at all times within any monitoring period, the response coefficient of each processing parameter in any monitoring period is determined. Based on the differences in the characteristic coefficients of each processing parameter between any monitoring period and all previous monitoring periods, and the distribution differences of each processing parameter, the weight parameter of each processing parameter in any monitoring period is determined. Combined with the response coefficient, the characteristic value of each processing parameter in any monitoring period is determined.

[0079] Based on the monitoring cycle division results in step S5.2, the processing parameters and grinding pressure within the monitoring cycle are further analyzed. First, within any monitoring cycle, by analyzing the differences between each processing parameter and grinding pressure at all times, and the differences between each processing parameter and grinding pressure and their preset rated values, the characteristic coefficients of each processing parameter in any monitoring cycle are determined, specifically:

[0080] Within any monitoring period, the difference between each processing parameter and grinding pressure and its preset rated value at each time point is calculated and then divided by the preset rated value. These results are recorded as the state deviation values ​​of each processing parameter and grinding pressure at each time point. The mean, variance, and range of the state deviation values ​​of each processing parameter and grinding pressure at all times are used to form their respective state sequences.

[0081] Calculate the comprehensive difference between the state sequence of each processing parameter and grinding pressure at all times within any monitoring period, and use the result of positively fusing the difference between each processing parameter and grinding pressure at all times within any monitoring period with the corresponding comprehensive difference as the characteristic coefficient of each processing parameter in any monitoring period.

[0082] It should be noted that the preset rated values ​​depend on the type of processing parameters and the type of processing equipment. In this embodiment, the processing parameters include rotational speed and feed rate. The preset rated value of rotational speed is 800 r / min. When the processing equipment is a honing head, the preset rated value of feed rate is 0.005 mm / r. When the processing equipment is a grinding wheel, the preset rated value of feed rate is 0.001 mm / r. The preset rated value of grinding pressure is 0.15 MPa.

[0083] It should be noted that there are many commonly used methods for measuring the differences between data sets. In this embodiment, the Euclidean distance between the state sequences of each processing parameter and grinding pressure at all times within any monitoring period is taken as the comprehensive difference between the state sequences of each processing parameter and grinding pressure at all times within any monitoring period. The DTW distance between each processing parameter and grinding pressure at all times within any monitoring period is taken as the difference between each processing parameter and grinding pressure at all times within any monitoring period. In practical applications, as other implementation methods, implementers may also use other methods such as Mahalanobis distance to measure the differences between data sets in combination with specific circumstances. This embodiment does not impose any special restrictions.

[0084] It should be understood that positive fusion refers to combining two or more indicators through addition or multiplication to obtain a comprehensive indicator, thereby more comprehensively and accurately assessing a phenomenon or problem. This fusion method is not limited to simple arithmetic operations, but can also include more complex statistical models and analytical methods. Implementers can choose according to specific circumstances, and this embodiment does not impose any special restrictions.

[0085] Preferably, as one implementation method, in this embodiment, the product of the difference between each processing parameter and grinding pressure and the corresponding comprehensive difference at all times within any monitoring period is used as the characteristic coefficient of each processing parameter in any monitoring period. In actual application, as another implementation method, the implementer may also adopt other positive fusion methods such as sum values ​​according to the specific situation. This embodiment does not impose any special restrictions.

[0086] The calculation methods for Euclidean distance and DTW distance are well-known techniques, and their specific calculation processes will not be elaborated further.

[0087] Based on the characteristic coefficients of each machining parameter under any monitoring period, it can be understood that the characteristic coefficients reflect the degree of deviation of the machining parameters from the ideal state in both dynamic response mode and macroscopic statistics, and are used to characterize the overall failure risk of the control strategy when dealing with roughness changes. If the difference between each machining parameter and the grinding pressure is greater at all times in the current monitoring period, it indicates that the synchronization between the machining parameters and the grinding pressure is worse, indicating that the machining parameters have not followed the changes in the grinding state well, and there may be problems of response lag or overcompensation. Therefore, it is necessary to adjust the machining parameters to optimize the machining accuracy of the planetary carrier. At the same time, if the comprehensive difference of the state sequence between each machining parameter and the grinding pressure at all times in the current monitoring period indicates that the statistical distribution difference between the machining parameters and the grinding pressure is large, it indicates that the machining parameters have not accurately controlled the fluctuation of the grinding pressure within the expected range, and the control strategy in the planetary carrier machining process has a failure risk. The corresponding characteristic coefficients are also large, and it is necessary to adjust the machining parameters in a timely manner to optimize the machining accuracy.

[0088] Conversely, if the difference between the processing parameters and the grinding pressure is small within the current monitoring period, it indicates that the two are highly synchronized and the processing parameters can follow the changes in the grinding state in real time and accurately. At the same time, if the comprehensive statistical difference between the two state sequences is also small, it indicates that the processing parameters have stably controlled the fluctuation of the grinding pressure within the ideal range. Both of these situations mean that the corresponding characteristic coefficients are small, reflecting that the current control strategy is operating well and has low risk, and can effectively ensure the processing accuracy and surface quality of the planetary carrier.

[0089] Furthermore, this embodiment determines the response coefficient of each processing parameter in any monitoring period based on the characteristic coefficient of each processing parameter under any monitoring period, and in combination with the degree of dispersion of the difference between each processing parameter and the preset rated value at all times within any monitoring period. Specifically:

[0090] In this embodiment, the product of the dispersion of each processing parameter and its characteristic coefficient at all times within any monitoring period is used as the response coefficient of each processing parameter in any monitoring period.

[0091] It should be noted that there are many methods to measure the degree of data dispersion. In this embodiment, the coefficient of variation of each processing parameter at all times within any monitoring period is taken as the degree of dispersion of each processing parameter at all times within any monitoring period. In practical applications, as other implementation methods, implementers may also use other methods such as variance or standard deviation to measure the degree of data dispersion in combination with specific circumstances. This embodiment does not impose any special restrictions on the selection of methods for measuring the degree of data dispersion.

[0092] The method for calculating the coefficient of variation is a well-known technique, and its specific calculation process will not be elaborated here.

[0093] Based on the response coefficient of each processing parameter in any monitoring period, it can be understood that the response coefficient reflects the instability and potential risk of the processing parameter deviation, and is used to characterize the urgency of the controller response. If the dispersion of the processing parameters in the current monitoring period is greater, it indicates that the difference in the processing parameters from the rated value within the current monitoring period is greater, and the corresponding response coefficient is also larger. This means that the stability of the processing parameters is worse, indicating that the controller has a dangerous state of large deviation and fluctuation during the planetary carrier processing. If not intervened in time, it will lead to the failure of planetary carrier processing. Therefore, it is necessary to adjust the processing parameters in time. At the same time, if the characteristic coefficient of each processing parameter is larger at all times in the current monitoring period, it indicates that the dynamic performance of the control process of the processing parameters during the planetary carrier processing is poor. Therefore, the response coefficient is also larger, and it is more necessary to adjust the processing parameters in time to optimize the planetary carrier processing.

[0094] Conversely, if the dispersion of the processing parameters is very small during the current monitoring period, it indicates that the parameter fluctuations are gentle, the operation is stable, and the deviation from the rated value is small. At the same time, if the characteristic coefficient of the parameter is also very small during the current monitoring period, it indicates that its synchronization with the grinding pressure is high and the dynamic control performance is good. Both of these situations will result in a small response coefficient, indicating that the current control process is stable and the risk is low, and the processing parameters do not need to be adjusted urgently.

[0095] Furthermore, this embodiment determines the weighting parameter for each processing parameter in any monitoring period based on the differences in the characteristic coefficients of each processing parameter between any monitoring period and all previous monitoring periods, as well as the differences in the distribution of each processing parameter. Specifically:

[0096] As one implementation method, in this embodiment, the weight parameter of the a-th processing parameter under the monitoring period x is... The expression is: In the formula, , These represent the characteristic coefficients of the a-th processing parameter under monitoring period x and under monitoring period v before monitoring period x, respectively. This represents the difference in the state sequence of the a-th processing parameter between monitoring period x and its previous monitoring period v; This indicates the number of all monitoring cycles between the start time of the current planetary carrier manufacturing process and the start time of monitoring cycle x.

[0097] It should be noted that in this embodiment, the Euclidean distance between the state sequence of the a-th processing parameter between the monitoring period x and its previous monitoring period v is taken as the difference between the state sequence of the a-th processing parameter between the monitoring period x and its previous monitoring period v. In actual application, as other implementation methods, implementers may also use other methods such as DTW distance to measure the difference between sequences in combination with specific circumstances. This embodiment does not impose any special restrictions on the selection of methods for measuring the difference between sequences.

[0098] Based on the weight parameters of each processing parameter in any monitoring period, it can be understood that the weight parameters reflect the deviation trend and severity relative to the historical average level. If the characteristic coefficient of the a-th processing parameter in monitoring period x is larger than the characteristic coefficient of the a-th processing parameter in the previous monitoring period v, it indicates that the control effect of the processing parameter in monitoring period x is worse than that in monitoring period v. Therefore, the corresponding weight parameter should be larger, and timely intervention is required. At the same time, if the difference in the state sequence of the a-th processing parameter between monitoring period x and its previous monitoring period v is larger, it indicates that the difference between the processing state in monitoring period x and the processing state in the historical monitoring period v is larger, increasing the uncertainty of processing parameter regulation. Therefore, special attention is required, and the corresponding weight parameter should be larger.

[0099] Conversely, if the characteristic coefficient of the a-th processing parameter under monitoring period x is comparable to or even better than that under historical monitoring period v, it indicates that the control effect of the current period is at a normal or good level in history. Therefore, its corresponding weight parameter is small and no priority intervention is required. At the same time, if the state sequence of the a-th processing parameter is very different between monitoring period x and historical monitoring period v, it indicates that the current processing state is highly consistent with the historical normal state, and the process is stable and predictable. Therefore, its corresponding weight parameter is also small, indicating that the parameter is running smoothly and the risk is low.

[0100] Furthermore, in this embodiment, based on the weight parameters of each processing parameter under any monitoring period and in combination with the response coefficient, the characteristic value of each processing parameter under any monitoring period is determined, specifically:

[0101] In this embodiment, the result of positively fusing the response coefficient and weight parameter of each processing parameter in any monitoring period is used as the feature value of each processing parameter in any monitoring period.

[0102] Preferably, the feature value extraction process provided in this embodiment is illustrated in the following diagram: Figure 2 As shown.

[0103] Preferably, as one implementation method, in this embodiment, the product of the response coefficient and the weight parameter of each processing parameter in any monitoring period is used as the feature value of each processing parameter in any monitoring period. In actual application, as another implementation method, the implementer may also adopt other positive fusion methods such as sum value according to the specific situation. This embodiment does not impose any special restrictions.

[0104] Based on the characteristic values ​​of each processing parameter in any monitoring period, it can be understood that the characteristic values ​​reflect the urgency of the current processing parameter adjustment and its relative severity in the past. They are used to characterize the final decision weight of the controller intervention during the planetary carrier processing. If the response coefficient of the processing parameter in the current monitoring period is larger, it indicates that the processing state in the current monitoring period is significantly different from the processing state in the historical monitoring period, and the corresponding characteristic value is larger. This means that the processing parameter must be adjusted immediately to correct the deviation. At the same time, if the weight parameter of the processing parameter in the current monitoring period is larger, it indicates that the uncertainty of the processing parameter adjustment in the current monitoring period is greater than that in the historical monitoring period, and therefore requires special attention. The corresponding characteristic value also increases accordingly.

[0105] Conversely, if the response coefficient of the processing parameter is smaller in the current monitoring period, it indicates that the current processing state is stable and the operation is stable, with no immediate risk. At the same time, if the weight parameter of the processing parameter is also smaller in the current monitoring period, it indicates that the current state is consistent with the historical norm, the process is predictable, and the uncertainty of regulation is low. Both of these situations together result in a smaller corresponding feature value, indicating that the parameter is operating well and does not require priority intervention. The controller can maintain the current strategy.

[0106] Thus, in each monitoring cycle, this embodiment calculates the characteristic value used to determine the priority intervention level of the controller by integrating the current control performance, fluctuation risk and historical deviation of the processing parameters. This enables the controller to accurately identify and prioritize the handling of the most critical parameter deviations, thereby effectively suppressing dynamic disturbances caused by uneven workpiece surfaces, and ensuring high stability and high precision in the planetary carrier processing.

[0107] S5.4: Based on the characteristic value of each processing parameter in the current monitoring cycle, determine the control coefficient of each processing parameter in the next monitoring cycle, so as to control each processing parameter in the next monitoring cycle.

[0108] In this embodiment, a PID controller is used to achieve automated control of the finishing process. First, the proportional gain and integral gain in the PID controller are determined using the attenuation curve method. The proportional gain obtained by the attenuation curve method is used as the reference value of the proportional gain. Furthermore, by periodically monitoring the machining parameters during the planetary carrier machining process and analyzing the staged grinding state changes caused by surface roughness differences in the same batch of workpieces, the gain parameters of the PID controller are optimized to adaptively respond to fluctuations in machining parameters, thereby improving the accuracy and automation level of the planetary carrier finishing process. The specific process is as follows:

[0109] In this embodiment, based on the characteristic values ​​of each processing parameter in the current monitoring cycle, the control coefficient of each processing parameter in the next monitoring cycle is determined, so as to control each processing parameter in the next monitoring cycle. Specifically:

[0110] As one implementation method, in this embodiment, the expression for the control coefficient of the a-th processing parameter in the next monitoring cycle after the current monitoring cycle is: In the formula, This represents the reference value of the proportional gain obtained by the attenuation curve method; This represents the normalized value of the characteristic value of the a-th processing parameter in the next monitoring cycle after the current monitoring cycle.

[0111] The process of determining the proportional gain and integral gain in a PID controller using the attenuation curve method is a well-known technique and will not be elaborated further.

[0112] Based on the control coefficients for each processing parameter, it can be understood that if the characteristic value under the current monitoring period is larger, it indicates that the current control deviation is larger. Therefore, the control coefficient should be increased to improve the response speed. Conversely, if the characteristic value under the current monitoring period is smaller, it indicates that the current control process is stable and the deviation is within an acceptable range. Therefore, the control coefficient should be reduced to avoid unnecessary oscillations or overshoots in the system, thereby enhancing the stability of the control.

[0113] Furthermore, in the next monitoring cycle after the current monitoring cycle, the difference between each processing parameter and the preset rated value at each time point is used as the input of the PID controller. The control coefficient of each processing parameter in the next monitoring cycle is used as the value of the proportional gain in the PID controller, and the control signal of each processing parameter is output to regulate each processing parameter.

[0114] The process of using a PID controller to control the processing parameters is a well-known technique and will not be described in detail here.

[0115] Thus, this embodiment quantifies the necessity and weight of control by dynamically generating feature values ​​through real-time analysis of multi-dimensional data during the processing. Based on this, the core gain parameters of the PID controller are adaptively adjusted. This method transforms traditional fixed parameter control into intelligent control based on real-time state feedback, enabling the controller to actively and accurately respond to dynamic disturbances caused by changes in workpiece surface roughness, thereby improving the processing accuracy of the planetary carrier.

[0116] It should be noted that the order of the embodiments described above is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, specific embodiments of this specification have been described above. Additionally, the processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired results. In some implementations, multitasking and parallel processing are possible or may be advantageous.

[0117] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0118] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them; modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions of some of the technical features, do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. An automated surface finishing method for the planetary carrier of a planetary gear reducer, characterized in that, The method includes the following steps: Real-time acquisition of grinding pressure and all processing parameters of the processing equipment during the processing of the current planetary carrier and all previous planetary carriers in the same batch, including rotational speed and feed rate; Based on the distribution of time intervals between all adjacent extreme values ​​of grinding pressure during the processing of each planetary carrier, the time characteristic value of each planetary carrier is determined; based on the dispersion of all grinding pressures during the processing of each planetary carrier, the characteristic weight of each planetary carrier is determined, and combined with the time characteristic value, the current planetary carrier processing is divided into multiple monitoring cycles. Within any monitoring period, by analyzing the differences between each processing parameter and grinding pressure at all times, as well as the differences between each processing parameter and grinding pressure and their preset rated values, the characteristic coefficients of each processing parameter in any monitoring period are determined. Combined with the dispersion of the differences between each processing parameter and the preset rated values ​​at all times within any monitoring period, the response coefficients of each processing parameter in any monitoring period are determined. Based on the differences in the characteristic coefficients of each processing parameter between any monitoring period and all previous monitoring periods, as well as the distribution differences of each processing parameter, the weight parameters of each processing parameter in any monitoring period are determined. Combined with the response coefficients, the characteristic values ​​of each processing parameter in any monitoring period are determined. Based on the characteristic values ​​of each processing parameter in the current monitoring cycle, the control coefficient of each processing parameter in the next monitoring cycle is determined so as to control each processing parameter in the next monitoring cycle.

2. The automated surface finishing method for the planetary carrier of a planetary reducer as described in claim 1, characterized in that, The time characteristic value of each planetary carrier is the average of the time intervals between all adjacent extreme values ​​of all grinding pressures during the processing of each planetary carrier.

3. The automated surface finishing method for the planetary carrier of a planetary gear reducer as described in claim 1, characterized in that, The characteristic weights of each planetary carrier are the result of normalizing the standard deviation of all grinding pressures during the machining process of each planetary carrier.

4. The automated surface finishing method for the planetary carrier of a planetary reducer as described in claim 1, characterized in that, The current planetary carrier manufacturing process is divided into multiple monitoring cycles, including: Calculate the product of the time characteristic value and the characteristic weight of each planetary support, and take the average of the product of the time characteristic value and the characteristic weight of all planetary supports in the same batch before the current planetary support as the length of the monitoring period. For the current planetary carrier manufacturing process, the time period from the start of the manufacturing process to the current time is divided into multiple monitoring cycles according to the length of the monitoring cycle.

5. The automated surface finishing method for the planetary carrier of a planetary gear reducer as described in claim 1, characterized in that, The method for determining the characteristic coefficients of each processing parameter in any monitoring period is as follows: Within any monitoring period, the difference between each processing parameter and grinding pressure and its preset rated value at each time point is calculated and then divided by the preset rated value. These results are recorded as the state deviation values ​​of each processing parameter and grinding pressure at each time point. The mean, variance, and range of the state deviation values ​​of each processing parameter and grinding pressure at all times are used to form their respective state sequences. Calculate the comprehensive difference between the state sequence of each processing parameter and grinding pressure at all times within any monitoring period, and use the result of positively fusing the difference between each processing parameter and grinding pressure at all times within any monitoring period with the corresponding comprehensive difference as the characteristic coefficient of each processing parameter in any monitoring period.

6. The automated surface finishing method for the planetary carrier of a planetary reducer as described in claim 5, characterized in that, The response coefficient of each processing parameter in any monitoring period is the product of the dispersion of each processing parameter at all times in any monitoring period and the characteristic coefficient.

7. The automated surface finishing method for the planetary carrier of a planetary gear reducer as described in claim 5, characterized in that, The expression for the weight parameter of each processing parameter in any monitoring period is: In the formula, The weight parameter represents the a-th processing parameter under monitoring period x; , These represent the characteristic coefficients of the a-th processing parameter under monitoring period x and under monitoring period v before monitoring period x, respectively. This represents the difference in the state sequence of the a-th processing parameter between monitoring period x and its previous monitoring period v; This indicates the number of all monitoring cycles between the start time of the current planetary carrier manufacturing process and the start time of monitoring cycle x.

8. The automated surface finishing method for the planetary carrier of a planetary gear reducer as described in claim 1, characterized in that, The characteristic value of each processing parameter in any monitoring period is the result of the positive fusion of the response coefficient and weight parameter of each processing parameter in any monitoring period.

9. The automated surface finishing method for the planetary carrier of a planetary reducer as described in claim 1, characterized in that, The expression for the control coefficient of each processing parameter in the next monitoring cycle is: In the formula, This represents the control coefficient for the a-th processing parameter in the next monitoring cycle following the current monitoring cycle; This represents the reference value of the proportional gain obtained by the attenuation curve method; This represents the normalized value of the characteristic value of the a-th processing parameter in the next monitoring cycle after the current monitoring cycle.

10. The automated surface finishing method for the planetary carrier of a planetary gear reducer as described in claim 1, characterized in that, The adjustment of each processing parameter in the next monitoring cycle includes: In the next monitoring cycle after the current monitoring cycle, the difference between each processing parameter and the preset rated value at each time point is used as the input of the PID controller. The control coefficient of each processing parameter in the next monitoring cycle is used as the value of the proportional gain in the PID controller, and the control signal of each processing parameter is output to regulate each processing parameter.

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