Control method and system for centralized chip removal machine of numerical control machine tool

Abstract

The invention relates to the technical field of automatic chip removal, in particular to a control method and system for a centralized chip removal machine of a numerical control machine tool, in the control method and system, the adjusting process of compression pressure is optimized through accurate calculation of the chip expansion rate, the cooling rate and the density change, and the influence of temperature change on the compression effect can be more accurately controlled. Through the combination of the expansion coefficient and the cooling time, the temperature fluctuation is monitored in real time, and the compression process is always kept in the optimal state under different machining conditions according to the deviation adjustment of the chip form and the compression pressure. The compression pressure is adjusted on the basis of the chip form data, so that the compression device has higher adaptability to iron chips of different shapes and types, unnecessary energy waste and machine damage are reduced, and the overall operation efficiency is improved. In addition, by dynamically calculating the chip removal flow speed, the conveying resistance and the periodic fluctuation, the chip removal path can be optimized in real time in the machining process.

Description

Technical Field

[0001] The present invention relates to the technical field of automated chip removal, and in particular to a control method and system for a centralized chip removal machine for a numerically controlled machine tool. Background Art

[0002] The field of automated chip removal technology includes methods for collecting, conveying and treating metal scraps, iron chips, aluminum chips and other waste materials generated during machine tool processing. The core content of this technical field includes the design of chip removal devices, the optimization of conveying mechanisms, and the compression and storage of chips. Automated chip removal technology has gradually developed into an integrated chip removal system, including intelligent conveying, centralized processing and waste recycling. By optimizing the conveying path, automatically adjusting the conveying speed and using efficient compression devices to improve chip removal capabilities, it is more suitable for high-intensity and high-precision processing environments.

[0003] Among them, a control method for a centralized chip conveyor for CNC machine tools refers to the method of centrally conveying the iron chips generated during the machining process of the machine tool to the chip conveyor through a conveying device, and compressing the iron chips into blocks through a specific control strategy in the chip conveyor. This control method mainly covers the operation control of the conveyor belt, the adjustment of the iron chip feed amount, and the start and stop management of the compression device. Specifically, the method controls the start and stop of the conveyor belt according to the amount of iron chips collected, and adjusts the conveying speed to maintain a stable feeding state; in the chip conveyor, the accumulation of iron chips is monitored by a pressure sensor, and the compression device is controlled to start at an appropriate time to achieve efficient compression of the iron chips into blocks; in addition, the method also includes the control of the discharge port of the chip conveyor to ensure that the compressed iron blocks are discharged in an orderly manner.

[0004] The control method of the prior art mainly realizes the chip removal process by starting and stopping the conveyor belt and simply starting and stopping the compression device. However, this method is controlled only according to the amount of iron chips collected or the accumulation situation, ignoring the complex influence of factors such as the shape of iron chips, density changes, and cooling rate on the compression efficiency. For example, the prior art cannot adjust the compression pressure in real time to cope with the influence of temperature fluctuations and cooling rates during processing, resulting in the difficulty of maintaining consistent compression effects, and even causing excessive wear of the machine or uneven accumulation of iron chips. In addition, the adjustment of the chip removal path also relies on a fixed control strategy, and fails to consider the real-time changes in resistance in the conveying channel, resulting in frequent blockages and flow deviations during the chip removal process. Due to the lack of periodic fluctuation analysis, the instability of the chip removal flow rate has not been effectively managed, affecting the efficient operation and energy efficiency of the equipment. Finally, the logic of power regulation in the prior art is relatively simple, and the power is only set by experience, and it fails to accurately match the chip removal requirements and compression state, resulting in unnecessary energy waste and unreasonable distribution of mechanical loads. These deficiencies directly affect the efficient operation and long-term stability of the chip conveyor. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings in the prior art and to propose a control method and system for a centralized chip conveyor of a CNC machine tool.

[0006] In order to achieve the above object, the present invention adopts the following technical solution: a control method for a centralized chip conveyor of a CNC machine tool, comprising the following steps: S1: Obtain the temperature data of the debris, compression chamber and environment, calculate the debris expansion rate in combination with the expansion coefficient, analyze the influence of the expansion rate and cooling rate on the density, adjust the compression pressure, and obtain the compression pressure after temperature compensation; S2: based on the temperature-compensated compression pressure, obtaining chip morphology data, calculating the optimal initial compression pressure, and adjusting the compression pressure according to the deviation to obtain the compression pressure after modal optimization; S3: Obtain the flow velocity data of the chips at the nodes of the chip removal and conveying channel, calculate the conveying resistance and analyze the resistance distribution, determine the abnormal area and adjust the chip removal flow direction to obtain the adjusted chip removal path; S4: Based on the adjusted chip removal path, obtain the machine tool processing task record, calculate the average chip removal flow rate, analyze the periodic changes, determine the change point and adjust the chip removal path activation time to obtain the periodically optimized chip removal path; S5: Based on the chip removal path after cycle optimization, the optimal power of the conveying motor is set, the matching degree is analyzed and the power is adjusted, and the compression pressure after modal optimization is integrated to obtain the chip conveyor conveying and compression operation control results.

[0007] As a further scheme of the present invention, the compression pressure after temperature compensation includes the chip expansion rate, cooling rate, and compressor pressure setting value; the compression pressure after modal optimization includes the optimal compression initial pressure, compression curve matching value, and compression pressure adjustment deviation; the adjusted chip removal path includes conveying resistance value, resistance distribution, and chip removal flow direction adjustment; the chip removal path after cycle optimization includes average chip removal flow rate, chip removal stage change point, and conveying path activation time; the chip conveyor conveying and compression operation control results include optimal power output value, chip removal load matching degree, conveying motor power setting value, and compression pressure after modal optimization.

[0008] As a further solution of the present invention, the step of obtaining the temperature-compensated compression pressure is specifically as follows: S111: obtaining temperature sensor data in the compression chamber, including chip temperature, compression chamber temperature and ambient temperature, obtaining chip expansion test data of each material during machine tool processing, extracting a reference value of the expansion coefficient of the corresponding material, calculating the product of the chip temperature and the reference value of the expansion coefficient, and obtaining the current chip expansion rate; S112: Get the cooling time of the chips under each temperature condition using the formula: ; Calculate the cooling rate under the current environment ; in, represents the initial temperature of the debris, represents the ambient temperature, represents the final temperature reached, represents the cooling time of the debris, represents the cooling constant; S113: Analyze the influence of the current chip expansion rate and cooling rate on the change of chip density, determine whether the compression pressure needs to be adjusted, set the pressure value of the compressor on the chip conveyor according to the adjustment requirements, and obtain the compression pressure after temperature compensation.

[0009] As a further solution of the present invention, the step of obtaining the compression pressure after the modal optimization is specifically as follows: S211: Based on the compression pressure after temperature compensation, the chip morphology data of the laser sensor is obtained, and the distribution of long chips, short chips, and powder chips in the chip removal process is detected respectively, and the flow sensor installed in the chip removal machine is called to monitor the chip removal speed, and the pressure change rate inside the compression chamber is obtained. According to the data, the corresponding database of chip morphology and compression pressure is queried, and the compression curve corresponding to each chip morphology in the chip removal process is mapped to obtain the chip morphology compression curve information; S212: Based on the chip morphology compression curve information, the formula is used: ; Calculate the optimal initial compression pressure ; in, The chip shape The corresponding specific compression pressure, The chip shape The distribution ratio in the current chip removal process, is the number of types of chip morphology; S213: Matching the optimal initial compression pressure with the compression curve, analyzing the deviation between the optimal initial compression pressure and the compression pressure setting value after temperature compensation, adjusting the current compression pressure setting based on the deviation, and obtaining the compression pressure after modal optimization.

[0010] As a further solution of the present invention, the step of obtaining the adjusted chip removal path is specifically as follows: S311: Obtain the flow velocity data of the chips at the node of the chip conveying channel using the formula: ; Calculate the conveying channel node corresponding to the current chip removal path The conveying resistance , obtain the transport resistance distribution information; in, is the friction coefficient of the conveying channel, is the total length of the conveying channel, is the chip packing density, is the diameter of the delivery channel pipe; S312: Based on the transport resistance distribution information, the formula is used: ; Calculate the resistance gradient at the transport channel node , if the resistance gradient If the set abnormal threshold is exceeded, it is judged that there is abnormal resistance in the target area, and the adjusted chip removal path is obtained by adjusting the abnormal area; in, It is a transport channel node The pipeline location at Represents the next monitoring node along the conveying path.

[0011] As a further solution of the present invention, the step of obtaining the chip removal path after the cycle optimization is specifically as follows: S411: Based on the adjusted chip removal path, obtain the machine tool processing task record, including the task time interval and the cutting material type, using the formula: ; Calculate the average chip flow rate for each task ; in, represents the sampling time interval, For the task The total duration of Representative Tasks in time Instantaneous chip removal flow rate; S412: Average chip removal flow rate based on each task , using the formula: ; Computational tasks The periodic fluctuation coefficient , the periodic fluctuation coefficient Compare with the preset fluctuation threshold, optimize and adjust according to the comparison result, and obtain the chip removal path after cycle optimization; in, , It's a task The maximum and minimum instantaneous chip removal flow rate.

[0012] As a further solution of the present invention, the steps for obtaining the control results of the conveying and compression operation of the chip conveyor are specifically as follows: S511: Based on the cycle-optimized chip removal path, according to the real-time resistance of each path, the optimal power output value of the conveyor belt conveying motor is set to obtain the optimal power analysis result of the motor; S512: Based on the optimal power analysis result of the motor, determine the matching degree between the optimal power output value and the current chip removal load, adjust the conveying motor power according to the matching degree, integrate the compression pressure after modal optimization, and obtain the chip conveyor conveying and compression operation control results.

[0013] A control system for a centralized chip conveyor of a numerically controlled machine tool, the control system for a centralized chip conveyor of a numerically controlled machine tool is used to execute the control method for the centralized chip conveyor of a numerically controlled machine tool, the system comprising: The chip expansion control module obtains the chip, compression chamber and ambient temperature data, calculates the chip expansion rate in combination with the expansion coefficient, analyzes the influence of the expansion rate and cooling rate on the density, adjusts the compression pressure, and generates the compression pressure after temperature compensation; The compression pressure optimization module obtains chip morphology data based on the temperature-compensated compression pressure, calculates the optimal initial compression pressure, adjusts the compression pressure according to the deviation, and generates a compression pressure after modal optimization; The chip removal path adjustment module obtains the flow velocity data of the chips at the chip removal channel node based on the compression pressure after the modal optimization, calculates the conveying resistance and analyzes the resistance distribution, determines the abnormal area and adjusts the chip removal flow direction to obtain the adjusted chip removal path; The periodic change analysis module obtains the machine tool processing task record based on the adjusted chip removal path, calculates the average chip removal flow rate, analyzes the periodic change, determines the change point and adjusts the chip removal path activation time to obtain the periodically optimized chip removal path; The conveying power adjustment module sets the optimal power of the conveying motor based on the chip removal path after the cycle optimization, analyzes the matching degree and adjusts the power, integrates the compression pressure after the modal optimization, and obtains the conveying and compression operation control results of the chip conveyor.

[0014] Compared with the prior art, the advantages and positive effects of the present invention are: In the present invention, by accurately calculating the chip expansion rate, cooling rate and density change, the adjustment process of the compression pressure is optimized, and the influence of temperature change on the compression effect can be controlled more accurately. By combining the expansion coefficient with the cooling time, not only the temperature fluctuation can be monitored in real time, but also the deviation adjustment can be made according to the chip morphology and the compression pressure to ensure that the compression process always maintains the best state under different processing conditions. The adjustment of the compression pressure based on the chip morphology data makes the compression device more adaptable to iron chips of different shapes and types, reduces unnecessary energy waste and machine damage, and improves the overall operating efficiency. In addition, by dynamically calculating the chip removal flow rate, conveying resistance and periodic fluctuations, the chip removal path can be optimized in real time during the processing process, and the chip removal activation time and flow direction can be automatically judged and adjusted, reducing blockages and abnormal phenomena in the chip removal process, and improving the stability and work efficiency of the equipment. Finally, through power regulation, the load matching degree of the conveying motor and the compressor is guaranteed, so that the overall power consumption of the chip conveyor is more reasonably controlled and energy consumption is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the workflow of the present invention; Figure 2 A flow chart of obtaining the compression pressure after temperature compensation according to the present invention; Figure 3 A flow chart for obtaining the compression pressure after modal optimization in the present invention; Figure 4 A flow chart for obtaining an adjusted chip removal path for the present invention; Figure 5 A flow chart of the chip removal path after obtaining cycle optimization for the present invention; Figure 6 The present invention is a flow chart for obtaining the conveying and compression operation control results of the chip conveyor. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0017] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, in the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0018] See also Figure 1 The present invention provides a technical solution: a control method for a centralized chip conveyor of a CNC machine tool, comprising the following steps: S1: Obtain the temperature data of the debris, compression chamber and environment, calculate the debris expansion rate in combination with the expansion coefficient, analyze the influence of the expansion rate and cooling rate on the density, adjust the compression pressure, and obtain the compression pressure after temperature compensation; S2: Based on the compression pressure after temperature compensation, the chip morphology data is obtained, the optimal initial compression pressure is calculated, and the compression pressure is adjusted according to the deviation to obtain the compression pressure after modal optimization; S3: Obtain the flow velocity data of the chips at the nodes of the chip removal and conveying channel, calculate the conveying resistance and analyze the resistance distribution, determine the abnormal area and adjust the chip removal flow direction to obtain the adjusted chip removal path; S4: Based on the adjusted chip removal path, obtain the machine tool processing task record, calculate the average chip removal flow rate, analyze the periodic changes, determine the change point and adjust the chip removal path activation time to obtain the periodically optimized chip removal path; S5: Based on the chip removal path after cycle optimization, set the optimal power of the conveying motor, analyze the matching degree and adjust the power, integrate the compression pressure after modal optimization, and obtain the control results of the chip conveyor conveying and compression operation; The compression pressure after temperature compensation includes the chip expansion rate, cooling rate, and compressor pressure setting value. The compression pressure after modal optimization includes the optimal compression initial pressure, compression curve matching value, and compression pressure adjustment deviation. The adjusted chip removal path includes the conveying resistance value, resistance distribution, and chip removal flow direction adjustment. The chip removal path after cycle optimization includes the average chip removal flow rate, chip removal stage change point, and conveying path activation time. The chip conveyor conveying and compression operation control results include the optimal power output value, chip removal load matching degree, conveying motor power setting value, and compression pressure after modal optimization.

[0019] See also Figure 2 , the steps for obtaining the compression pressure after temperature compensation are as follows: S111: obtaining temperature sensor data in the compression chamber, including chip temperature, compression chamber temperature and ambient temperature, obtaining chip expansion test data of each material during machine tool processing, extracting a reference value of the expansion coefficient of the corresponding material, calculating the product of the chip temperature and the reference value of the expansion coefficient, and obtaining the current chip expansion rate; Obtain temperature sensor data in the compression chamber, including chip temperature, compression chamber temperature and ambient temperature, and measure the chip temperature at different time points during the machine tool processing The compression chamber temperature is 700K. The ambient temperature is 320K. The data is stored in the data recording module and used for subsequent calculations to obtain the chip expansion test data of each material during machine tool processing. For example, for the chips of 45# steel, the experimentally measured expansion coefficient benchmark value for K , this value comes from high temperature experimental measurement, the data is recorded in the material expansion coefficient database, after calling this value, the product of the chip temperature and the expansion coefficient reference value is calculated, the calculation process is as follows: , represents the current debris expansion rate, dimensionless; Represents the base value of the material expansion coefficient, in K ; represents the temperature of the debris in K; Represents the ambient temperature in K. Substitute the value: , the current debris expansion rate is calculated to be 0.0048.

[0020] S112: Get the cooling time of the chips under each temperature condition using the formula: ; Calculate the cooling rate under the current environment ; in, Represents the natural logarithm function and is used to calculate the logarithm of the temperature ratio, which helps to linearize the exponential cooling process and make the calculated results more suitable for linear analysis. Represents the initial temperature of the debris, in units of (Kelvin). This temperature is measured using a thermal imager immediately after the debris is generated. Represents the ambient temperature, also in units of This temperature is continuously monitored by temperature sensors installed in the workshop. Represents the final temperature reached, and the unit is This temperature is obtained by measuring the chip temperature again using a thermal imager after a set cooling time. Represents the cooling time of the debris, in units of (seconds), which is the time interval set before the experiment, such as the time from the generation of debris to the next temperature measurement. stands for cooling constant, which is a dimensionless parameter that takes into account the heat transfer properties of the material and the efficiency of the cooling medium. This constant was determined through previous thermodynamic experiments, in which the cooling efficiency of different material and cooling medium combinations was compared to obtain an average value.

[0021] Set initial temperature , ambient temperature , final temperature , Cooling time , the experimentally measured cooling constant , enter the formula to calculate: The cooling rate of the debris is calculated to be 0.1733s .

[0022] S113: analyzing the influence of the current chip expansion rate and cooling rate on the change of chip density, determining whether the compression pressure needs to be adjusted, setting the pressure value of the compressor on the chip conveyor according to the adjustment requirements, and obtaining the compression pressure after temperature compensation; Based on the calculated current debris expansion rate and the calculated cooling rate of the debris , analyze the influence of these two parameters on the change of debris density, and use the following steps to compare and calculate: Calculate the density of debris after cooling: According to the formula of thermal expansion affecting density: ,in, is the density of the debris after cooling, is the initial density of the debris, is the expansion rate of the debris. It indicates the density decrease caused by the volume expansion of the debris under temperature change. The correlation between cooling rate and density change: Since the cooling rate affects the duration of the thermal expansion effect, a density change influencing factor is set , calculate its corrected density: ,in, is the cooling rate corrected debris density, is the experimentally determined cooling influence coefficient (used to adjust the effect of cooling rate on density). Determine the density drop and adjust the compression pressure: ,like kg / m , adjust the compression pressure, otherwise keep the current setting.

[0023] Set initial density kg / m , the calculated debris expansion rate , cooling rate s , the cooling rate influence factor is experimentally measured , then: Calculate the density of the debris after cooling: . Calculate the density corrected for cooling rate: . Calculate the density drop: .because kg / m , the compression pressure needs to be adjusted according to If the density decreases significantly (for example, more than 50kg / m ), which means that the chips expand greatly, which has a greater impact on the chip density in the compression chamber, resulting in reduced chip removal efficiency. Too much chips may have a negative impact on the cooling effect, so the compression pressure needs to be increased to counteract the impact of expansion and restore the appropriate density. The adjustment range of the compression pressure is usually based on the chip expansion rate. Density corrected for cooling rate According to the known experimental data and formula, set the The density decrease requires a certain amount of compression pressure. Assuming that every decrease of 1kg / m If the compression pressure adjustment amount needs to be increased by 0.5 bar, the adjusted compression pressure can be calculated by the following formula : ,in, is the current compression pressure of the compressor, is an experimentally obtained coefficient (e.g., 0.5 bar / kg / m ),and is the calculated density drop. In actual operation, the operator adjusts the pressure setting on the compressor based on the density change and the calculated results. During operation, the increase in compressor pressure should be kept steady to avoid over-adjustment that causes over-compression or uneven compression of the chips. By making gradual adjustments, it is possible to ensure that the density of the chips remains within a reasonable range while maintaining stability and chip removal efficiency during the process. For example, assuming the current compression pressure is bar, the calculated density drop kg / m , then according to the above adjustment formula, the adjustment amount of compression pressure is: Through this method, the operator can adjust the compression pressure of the compressor to 159 bar to ensure the compression effect after the expansion of the debris and obtain the compression pressure after temperature compensation.

[0024] See also Figure 3 , the steps for obtaining the compression pressure after modal optimization are as follows: S211: Based on the compression pressure after temperature compensation, the chip morphology data of the laser sensor is obtained, and the distribution of long chips, short chips, and powder chips in the chip removal process is detected respectively. The flow sensor installed in the chip removal machine is called to monitor the chip removal speed, and the pressure change rate inside the compression chamber is obtained. According to the data, the corresponding database of chip morphology and compression pressure is queried, and the compression curve corresponding to each chip morphology in the chip removal process is mapped to obtain the chip morphology compression curve information; The chip morphology data, including long chips, short chips, and powder chips, are obtained from the optical / laser sensor, and the proportion information of each type of chips is recorded. Long chips are long and easy to bend and entangle, short chips are broken particles, and powder chips are in a state of accumulation of tiny particles. These forms affect the filling density and force distribution during the compression process. The flow sensor data on the chip conveyor belt is obtained to detect the chip flow rate per unit time. Assuming that the current chip removal speed is 0.015 m³ / s, the pressure change rate of the compression chamber is obtained, and the pressure change rate in the current detection cycle is set to 1000 Pa / s. These data are used as input parameters to find the corresponding data in the chip morphology and compression curve database. In the database, different chip types correspond to different compression characteristic curves. For example, long chips have strong elastic recovery characteristics, and their compression curves usually show a high initial pressure requirement, while short chips can be effectively compressed at a lower pressure due to their broken particle shape. Powder chips are easy to fill at low pressure due to their large stacking density, but easy to form a hardened structure at high pressure. By querying the database, the system matches the compression curve corresponding to the current chip mixing ratio to obtain the chip morphology compression curve data.

[0025] S212: Based on the chip morphology compression curve information, the formula is used: ; Calculate the optimal initial compression pressure ; in, The chip shape The corresponding specific compression pressure, in Pa, is found in the database for experimental compression pressure data of different chip types, for example, 500,000Pa for long chips, 300,000Pa for short chips, and 100,000Pa for powder chips. These values ​​are determined experimentally, and the density change curves of each chip morphology are measured under different pressure conditions, and key point data are extracted. The chip shape The distribution ratio in the current chip removal process is dimensionless and is calculated by optical / laser sensors after detecting the chip morphology. For example, long chips are 60%, short chips are 30%, and powder chips are 10%. These ratios are monitored in real time and calculated based on the volume of chips entering the compression chamber per unit time. It is the number of chip types, usually 3, corresponding to long chips, short chips, and powder chips, and can be expanded according to actual conditions.

[0026] Substitute the above values: , the optimal initial compression pressure is calculated to be 400,000Pa.

[0027] By combining the distribution ratio of various types of chips and their corresponding compression characteristics, the optimal initial compression pressure suitable for the current chip type is calculated. Compared with the traditional single pressure setting method, this method can dynamically adapt to different working conditions and improve the adaptability of the chip removal system.

[0028] S213: matching the optimal initial compression pressure with the compression curve, analyzing the deviation between the optimal initial compression pressure and the compression pressure setting value after temperature compensation, adjusting the current compression pressure setting based on the deviation, and obtaining the compression pressure after modal optimization; According to the optimal initial compression pressure matching chip morphology compression curve data, analyze the deviation between the optimal initial compression pressure and the compression pressure after temperature compensation, and judge whether the deviation exceeds the set threshold. The set threshold is usually a 5% error range, that is, if , you need to adjust the current compression pressure. For example, if the compression pressure after temperature compensation is 380,000Pa, calculate: , .in, It is the compression pressure after temperature compensation, in Pa, calculated by the temperature compensation module, for example 380,000Pa. is the compression pressure deviation, in Pa, calculated as , which indicates the difference between the current compression pressure and the optimal compression initial pressure. It is the adjustment coefficient, dimensionless, experimentally measured, used to determine the amplitude of deviation compensation, and must meet the following specific demarcation standards: Response speed of chip removal system: High response speed (>2MPa / s): When the pressure adjustment ability of the chip removal system is strong and the response is fast, adjust the proportional coefficient It should be small to prevent the pressure from fluctuating due to too fast pressure adjustment. It is usually set between 0.5-0.6. Low response speed (<1MPa / s): If the system pressure response is slow, a larger The value is set to increase the adjustment range and make the system reach the desired pressure as soon as possible. It is usually set between 0.8-0.9. Compression characteristics of chip types: High resilience chips (such as long chips, ductile metals): These chips have high elastic recovery ability during compression. Too small pressure adjustment will cause chip rebound and affect the stability of the chip conveyor. The setting is relatively high, usually between 0.75-0.9. Low resilience chips (such as short chips, powder chips): The shape of these chips is relatively stable, and there will be no obvious rebound phenomenon during the compression process, so The setting is relatively low, usually between 0.5-0.7, to prevent unnecessary energy consumption caused by excessive pressure adjustment. System stability requirements: High stability requirements (high-precision processing environment): If the system has high requirements for the stability of chip removal pressure, such as CNC machine tools used for high-precision processing, it is necessary to prevent the impact caused by excessive pressure adjustment. Set it between 0.5-0.7 to ensure the smooth operation of the system. Low stability requirements (normal processing or rough processing environment): If the processing environment allows a certain range of pressure fluctuations, it can be appropriately increased. , so that the system can quickly adjust the pressure, usually set between 0.75-0.9, to accelerate the optimization process of chip removal pressure. In summary, adjust the proportional coefficient The setting of needs to comprehensively consider the response speed of the chip removal system, the compression characteristics of the chip type and the system stability requirements, determine the reasonable range through experimental testing, and adjust it according to the processing requirements. For example, if the pressure response speed of the system is 1.5MPa / s, it mainly processes short chips, and the processing environment requires high stability, then Set it around 0.6; if the system response speed is slow (<1MPa / s), mainly processing long chips and the processing environment allows pressure fluctuations, then Set it around 0.85 to increase the pressure adjustment range. is the adjusted compression pressure, in Pa, used to control the final pressure setting of the compressor. Since the error exceeds the threshold, the system performs compressor pressure adjustment and sets the adjustment proportional coefficient is 0.8, then the adjusted compression pressure is: ; The adjusted compression pressure is set to 396,000Pa, and the compression pressure after modal optimization is obtained.

[0029] See also Figure 4 , the specific steps for obtaining the adjusted chip removal path are: S311: Obtain the flow velocity data of the chips at the node of the chip conveying channel using the formula: ; Calculate the conveying channel node corresponding to the current chip removal path The conveying resistance , obtain the transport resistance distribution information; in, is the conveying channel friction coefficient (dimensionless), determined experimentally and derived from measured pressure drop data at known flow rates. is the total length of the conveying channel (m), which is provided by the design parameters of the conveying channel. is the chip packing density (kg / m³), which is determined experimentally and calculated by measuring the mass of a certain volume of chips. For example, if the mass of 5L (0.005m³) chips is 4kg, then kg / m³. It is a transport channel node The chip flow rate (m / s) at the position is measured by a flow rate sensor. is the conveying channel pipe diameter (m), which is provided by the physical design of the conveying system.

[0030] Bring in the flow rate data of the three nodes respectively m / s, m / s, m / s Calculate the conveying resistance: ; ; ; The calculated conveying resistance represents the pressure loss caused by flow friction at different monitoring nodes. The conveying resistance at the first node is the highest, reaching 1152Pa, the resistance at the second node drops to 512Pa, and the resistance at the third node further drops to 128Pa. This indicates that the energy loss in the chip removal process varies significantly along the conveying path, and the conveying resistance distribution data is obtained.

[0031] S312: Based on the transport resistance distribution information, the formula is used: ; Calculate the resistance gradient at the transport channel node , if the resistance gradient If the set abnormal threshold is exceeded, it is judged that there is abnormal resistance in the target area, and the adjusted chip removal path is obtained by adjusting the abnormal area; in, It is a transport channel node The pipeline position (m) at the location is provided by the design parameters of the transport channel. Represents the next monitoring node along the conveying path.

[0032] Setting anomaly thresholds Pa / m, calculated as: ; ; The calculation results show that the resistance gradient of the first monitoring section is -128Pa / m, which is greater than the set abnormal threshold. Pa / m, indicating that there is an abnormal resistance distribution in this area, which may be caused by chip accumulation, local narrowing of the conveying channel, or uneven chip flow rate. The resistance gradient of the second monitoring section is -76.8Pa / m, which is less than the abnormal threshold, indicating that the conveying condition in this area is relatively normal. Therefore, it is necessary to adjust the chip flow direction, optimize the chip conveying path, use an auxiliary chip removal path for dredging, and calculate the adjusted flow distribution: .in, is the adjusted transport channel node The volume flow rate (m³ / s) at is calculated and represents the chip conveying flow rate after adjusting the chip removal path. It is the original transport channel node Volume flow rate at (m³ / s), is the flow distribution coefficient (dimensionless), which is used to describe the redistribution ratio of the chip removal flow. The larger the value, the larger the adjusted flow rate ratio is, and the more chips are diverted to other paths. The setting principle is as follows: when the conveying resistance gradient When the chip removal pressure loss in a certain section is too high, the risk of blockage increases. Should be increased to reduce the flow rate of this path, usually set in the range of 0.2 ≤ ≤0.5. When the auxiliary path has a strong conveying capacity (large pipe diameter and low friction coefficient), For example, in actual measurement, if the resistance of a certain area reaches 130Pa / m, which is higher than the threshold, , you can set To enhance diversion capabilities.

[0033] Bring in data: ; ; The calculation results show that after flow adjustment, the chip removal flow of the first conveying path decreased from 0.036m³ / s to 0.0252m³ / s, and the chip removal flow of the second conveying path increased from 0.024m³ / s to 0.0348m³ / s. That is, part of the chip flow was diverted to the conveying path with less resistance, which optimized the overall chip removal path, alleviated the pressure loss in the high resistance area, and obtained the adjusted chip removal path.

[0034] See also Figure 5 , the specific steps for obtaining the chip removal path after cycle optimization are: S411: Based on the adjusted chip removal path, obtain the machine tool processing task record, including the task time interval and the cutting material type, using the formula: ; Calculate the average chip flow rate for each task ; in, Represents the sampling time interval in seconds, which is used for numerical integration of discrete time steps. For the task The total duration of Representative Tasks in time Instantaneous chip removal flow.

[0035] The instantaneous flow data for different tasks are set as follows: Task 1: m³ / s, duration Hour; Task 2: m³ / s, duration Hour; Task 3: m³ / s, duration Hour.

[0036] Calculate the average chip flow rate for each task: ; ; ; The calculated average chip removal flow rate represents the stable chip removal trend under different machining tasks. The average flow rate of task 1 is the largest, and that of task 3 is the smallest. The average chip removal flow rate of each task is obtained.

[0037] S412: Average chip flow rate based on each task , using the formula: ; Computational tasks The periodic fluctuation coefficient ; in, , It's a task The maximum and minimum instantaneous chip removal flow rates, in m³ / s, are directly recorded by the data acquisition system.

[0038] Combined with the parameter calculation of S411: ; ; ; like , it is considered that the task cycle fluctuates greatly, and the chip removal path needs to be adjusted. Set the fluctuation threshold , it is determined that the transportation path activation time of Task 1 and Task 3 needs to be optimized. Adjust the transportation path switching time of Task 1 and Task 3, and adopt the optimization adjustment strategy: ,in, Represents the time adjustment coefficient of the task, which is set as follows: When the task cycle fluctuates greatly ( ), the adjustment coefficient Take a larger value (510min) to make the path adjustment more obvious; when the task cycle fluctuation is small ( ), the adjustment coefficient Take (35min), moderately optimize the path; when the task cycle fluctuation is low ( ), keep the path unchanged and do not make adjustments.

[0039] Set up tasks 1 and 3 min, min, calculate: ; ; in, It's a task The original transport path activation time, in minutes, is obtained from the task scheduling plan; It's a task The optimized conveying path activation time is in minutes. The calculation results show that the conveying path activation time of task 1 needs to be adjusted by 0.86 minutes, and that of task 3 by 0.85 minutes, to obtain the chip removal path after cycle optimization.

[0040] See also Figure 6 , the specific steps for obtaining the control results of the chip conveyor conveying and compression operation are as follows: S511: Based on the chip removal path after cycle optimization and according to the real-time resistance of each path, the optimal power output value of the conveyor belt conveying motor is set to obtain the optimal power analysis result of the motor; First, the current resistance data of each path is obtained through the pressure sensors installed along the conveying channel. The acquisition of resistance data should take into account parameters such as channel length, flow rate, and fluid dynamics, and be compared with historical data to confirm the stability of the resistance. The judgment of resistance needs to refer to the channel cross-sectional area and the pressure change rate per unit time, and set the benchmark resistance range. For example, in a specific channel, when the resistance change rate is less than 0.05 kPa / s, the resistance is considered stable. If it is greater than 0.05 kPa / s but less than 0.2 kPa / s, it is judged to be a resistance fluctuation state. If it is greater than 0.2 kPa / s, it is considered to be an abnormal resistance and power adjustment is required. When setting the optimal power output value of the conveying motor, it is necessary to establish a power mapping table based on different types of chips. The establishment of the mapping table needs to be based on the density, particle diameter, flow characteristics and conveying volume per unit time of the chips. If the chip density is between 500-700 kg / m³ and the conveying volume per unit time is within the range of 2-3 kg / s, the basic power setting value of the motor is 1.5 kW. When the density exceeds 700 kg / m³ or the conveying volume exceeds 3 kg / s, the power setting value needs to be increased by 10%-20% to ensure conveying stability. If the density is lower than 500 kg / m³ and the conveying volume is less than 2 kg / s, the power setting value can be reduced by 5%-10%. On this basis, dynamic adjustments are made according to real-time resistance data. If the resistance is within a stable range, the current power output is maintained. If the resistance fluctuates, the adjustment range is set based on the resistance change rate. For example, for every 0.05 kPa / s increase in the resistance fluctuation rate, the power increases by 5%, and the maximum does not exceed 30% of the rated power. Finally, the optimal power output value of each path is set in the conveying control system and stored in the system as an operating parameter.

[0041] S512: Based on the optimal power analysis result of the motor, determine the matching degree between the optimal power output value and the current chip removal load, adjust the conveying motor power according to the matching degree, integrate the compression pressure after modal optimization, and obtain the conveying and compression operation control results of the chip conveyor; First, call the current operating data of the conveying motor, including real-time power consumption, speed and load curve, and calculate the power matching degree under the current load. The matching degree is judged based on the ratio of the theoretical optimal power to the current operating power. Set the matching degree judgment interval. If the matching degree is in the range of 95%-105%, it is considered that the current power output meets the load requirements. If the matching degree is lower than 95%, it indicates that the current power is insufficient and the output needs to be increased. The increase is set according to the gap ratio. For example, if the matching degree is 90%, the power is increased by 5%. If the matching degree is higher than 105%, it indicates that there is excess power. The reduction is set according to the excess ratio. For example, if the matching degree is 110%, the power is reduced by 5%. The adjustment process needs to be combined with the modal optimization pressure of the compression system. If the compression system pressure is higher than 10MPa, when adjusting the conveying motor power, appropriately reduce the adjustment range and control it within the range of **3%-8%** to prevent power fluctuations from causing unstable transmission. In addition, during the power adjustment process, it is necessary to synchronously calculate the adjusted conveying efficiency and set the efficiency threshold. If the adjusted conveying efficiency is lower than 85%, the matching degree is recalculated and the adjustment range is reset until the matching degree and conveying efficiency are within a reasonable range. Finally, by adjusting the conveying motor power and integrating the compression pressure, the operation control results of the chip conveyor conveying and compression are obtained.

[0042] A control system for a centralized chip conveyor of a numerically controlled machine tool, the control system for a centralized chip conveyor of a numerically controlled machine tool is used to execute the control method for the centralized chip conveyor of a numerically controlled machine tool, and the system comprises: The chip expansion control module obtains the chip, compression chamber and ambient temperature data, calculates the chip expansion rate in combination with the expansion coefficient, analyzes the influence of the expansion rate and cooling rate on the density, adjusts the compression pressure, and generates the compression pressure after temperature compensation; The compression pressure optimization module obtains chip morphology data based on the temperature-compensated compression pressure, calculates the optimal initial compression pressure, adjusts the compression pressure according to the deviation, and generates the compression pressure after modal optimization; The chip removal path adjustment module obtains the flow velocity data of the chips at the chip removal channel nodes based on the compression pressure after modal optimization, calculates the conveying resistance and analyzes the resistance distribution, determines the abnormal area and adjusts the chip removal flow direction to obtain the adjusted chip removal path; The periodic change analysis module obtains the machine tool processing task records based on the adjusted chip removal path, calculates the average chip removal flow rate, analyzes the periodic changes, determines the change point and adjusts the chip removal path activation time to obtain the periodically optimized chip removal path; The conveying power adjustment module sets the optimal power of the conveying motor based on the chip removal path after cycle optimization, analyzes the matching degree and adjusts the power, integrates the compression pressure after modal optimization, and obtains the conveying and compression operation control results of the chip conveyor.

[0043] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in other forms. Any technician familiar with the profession may use the technical contents disclosed above to change or modify them into equivalent embodiments with equivalent changes and apply them to other fields. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A control method for a centralized chip conveyor of a CNC machine tool, characterized in that: The following steps are involved: S1: Obtain the temperature data of the debris, compression chamber and environment, calculate the debris expansion rate in combination with the expansion coefficient, analyze the influence of the expansion rate and cooling rate on the density, adjust the compression pressure, and obtain the compression pressure after temperature compensation; S2: based on the temperature-compensated compression pressure, obtaining chip morphology data, calculating the optimal initial compression pressure, and adjusting the compression pressure according to the deviation to obtain the compression pressure after modal optimization; S3: Obtain the flow velocity data of the chips at the nodes of the chip removal and conveying channel, calculate the conveying resistance and analyze the resistance distribution, determine the abnormal area and adjust the chip removal flow direction to obtain the adjusted chip removal path; S4: Based on the adjusted chip removal path, obtain the machine tool processing task record, calculate the average chip removal flow rate, analyze the periodic changes, determine the change point and adjust the chip removal path activation time to obtain the periodically optimized chip removal path; S5: Based on the chip removal path after cycle optimization, the optimal power of the conveying motor is set, the matching degree is analyzed and the power is adjusted, and the compression pressure after modal optimization is integrated to obtain the chip conveyor conveying and compression operation control results.

2. The control method for a centralized chip conveyor for a CNC machine tool according to claim 1, characterized in that: The compression pressure after temperature compensation includes the chip expansion rate, cooling rate, and compressor pressure setting value; the compression pressure after modal optimization includes the optimal compression initial pressure, compression curve matching value, and compression pressure adjustment deviation; the adjusted chip removal path includes the conveying resistance value, resistance distribution, and chip removal flow direction adjustment; the chip removal path after cycle optimization includes the average chip removal flow rate, chip removal stage change point, and conveying path activation time; the chip conveyor conveying and compression operation control results include the optimal power output value, chip removal load matching degree, conveying motor power setting value, and compression pressure after modal optimization.

3. The control method for a centralized chip conveyor for a CNC machine tool according to claim 2, characterized in that: The steps for obtaining the compression pressure after temperature compensation are specifically as follows: S111: obtaining temperature sensor data in the compression chamber, including chip temperature, compression chamber temperature and ambient temperature, obtaining chip expansion test data of each material during machine tool processing, extracting a reference value of the expansion coefficient of the corresponding material, calculating the product of the chip temperature and the reference value of the expansion coefficient, and obtaining the current chip expansion rate; S112: Get the cooling time of the chips under each temperature condition using the formula: ； Calculate the cooling rate under the current environment ; in, represents the initial temperature of the debris, represents the ambient temperature, represents the final temperature reached, represents the cooling time of the debris, represents the cooling constant; S113: Analyze the influence of the current chip expansion rate and cooling rate on the change of chip density, determine whether the compression pressure needs to be adjusted, set the pressure value of the compressor on the chip conveyor according to the adjustment requirements, and obtain the compression pressure after temperature compensation.

4. The control method for a centralized chip conveyor for a CNC machine tool according to claim 3, characterized in that: The steps for obtaining the compression pressure after the modal optimization are specifically as follows: S211: Based on the compression pressure after temperature compensation, the chip morphology data of the laser sensor is obtained, and the distribution of long chips, short chips, and powder chips in the chip removal process is detected respectively, and the flow sensor installed in the chip removal machine is called to monitor the chip removal speed, and the pressure change rate inside the compression chamber is obtained. According to the data, the corresponding database of chip morphology and compression pressure is queried, and the compression curve corresponding to each chip morphology in the chip removal process is mapped to obtain the chip morphology compression curve information; S212: Based on the chip morphology compression curve information, the formula is used: ； Calculate the optimal initial compression pressure ; in, The chip shape The corresponding specific compression pressure, The chip shape The distribution ratio in the current chip removal process, is the number of types of chip morphology; S213: Matching the optimal initial compression pressure with the compression curve, analyzing the deviation between the optimal initial compression pressure and the compression pressure setting value after temperature compensation, adjusting the current compression pressure setting based on the deviation, and obtaining the compression pressure after modal optimization.

5. The control method for a centralized chip conveyor for a CNC machine tool according to claim 4, characterized in that: The steps for obtaining the adjusted chip removal path are specifically as follows: S311: Obtain the flow velocity data of the chips at the node of the chip conveying channel using the formula: ； Calculate the conveying channel node corresponding to the current chip removal path The conveying resistance , obtain the transport resistance distribution information; in, is the friction coefficient of the conveying channel, is the total length of the conveying channel, is the chip packing density, is the diameter of the delivery channel pipe; S312: Based on the transport resistance distribution information, the formula is used: ； Calculate the resistance gradient at the transport channel node , if the resistance gradient If the set abnormal threshold is exceeded, it is judged that there is abnormal resistance in the target area, and the adjusted chip removal path is obtained by adjusting the abnormal area; in, It is a transport channel node The pipeline location at Represents the next monitoring node along the conveying path.

6. The control method for a centralized chip conveyor for a CNC machine tool according to claim 5, characterized in that: The steps for obtaining the chip removal path after cycle optimization are specifically as follows: S411: Based on the adjusted chip removal path, obtain the machine tool processing task record, including the task time interval and the cutting material type, using the formula: ； Calculate the average chip flow rate for each task ; in, represents the sampling time interval, For the task The total duration of Representative Tasks in time Instantaneous chip removal flow rate; S412: Average chip removal flow rate based on each task , using the formula: ； Computational tasks The periodic fluctuation coefficient , the periodic fluctuation coefficient Compare with the preset fluctuation threshold, optimize and adjust according to the comparison result, and obtain the chip removal path after cycle optimization; in, , It's a task The maximum and minimum instantaneous chip removal flow rate.

7. The control method for a centralized chip conveyor for a CNC machine tool according to claim 6, characterized in that: The steps for obtaining the control results of the conveying and compression operation of the chip conveyor are specifically as follows: S511: Based on the cycle-optimized chip removal path, according to the real-time resistance of each path, the optimal power output value of the conveyor belt conveying motor is set to obtain the optimal power analysis result of the motor; S512: Based on the optimal power analysis result of the motor, determine the matching degree between the optimal power output value and the current chip removal load, adjust the conveying motor power according to the matching degree, integrate the compression pressure after modal optimization, and obtain the chip conveyor conveying and compression operation control results.

8. A control system for a centralized chip conveyor of a CNC machine tool, characterized in that: According to the control method of a centralized chip conveyor for a CNC machine tool according to any one of claims 1 to 7, the system comprises: The chip expansion control module obtains the chip, compression chamber and ambient temperature data, calculates the chip expansion rate in combination with the expansion coefficient, analyzes the influence of the expansion rate and cooling rate on the density, adjusts the compression pressure, and generates the compression pressure after temperature compensation; The compression pressure optimization module obtains chip morphology data based on the temperature-compensated compression pressure, calculates the optimal initial compression pressure, adjusts the compression pressure according to the deviation, and generates a compression pressure after modal optimization; The chip removal path adjustment module obtains the flow velocity data of the chips at the chip removal channel node based on the compression pressure after the modal optimization, calculates the conveying resistance and analyzes the resistance distribution, determines the abnormal area and adjusts the chip removal flow direction to obtain the adjusted chip removal path; The periodic change analysis module obtains the machine tool processing task record based on the adjusted chip removal path, calculates the average chip removal flow rate, analyzes the periodic change, determines the change point and adjusts the chip removal path activation time to obtain the periodically optimized chip removal path; The conveying power adjustment module sets the optimal power of the conveying motor based on the chip removal path after the cycle optimization, analyzes the matching degree and adjusts the power, integrates the compression pressure after the modal optimization, and obtains the conveying and compression operation control results of the chip conveyor.

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