A control method and system for a centralized chip conveyor of a numerically controlled machine tool

Abstract

The present invention relates to the technical field of automatic chip removal, and specifically to a control method and system for a centralized chip removal machine used in a numerical control machine tool. In the present invention, by precisely 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 is monitored in real time, but also the adjustment can be made according to the deviation of the chip shape and the compression pressure, ensuring that the compression process always maintains the best state under different processing conditions. The adjustment of the compression pressure based on the chip shape data enables the compression device to have higher adaptability to iron chips of different shapes and types, reduces unnecessary energy waste and machine damage, and improves the overall operation 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.

Description

Technical Field

[0001] The present invention relates to the technical field of automatic chip removal, and particularly to a control method and system for a centralized chip removal machine for a numerical control machine tool. Background Art

[0002] The technical field of automatic chip removal includes methods for collecting, conveying, and processing waste materials such as metal chips, iron chips, and aluminum chips generated during the machining process of machine tools. 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 chip materials. The automatic chip removal technology has gradually developed into an integrated chip removal system, including aspects such as intelligent conveying, centralized processing, and waste material recycling. By optimizing the conveying path, automatically adjusting the conveying speed, and using efficient compression devices, the chip removal capacity is improved, making it more suitable for high-intensity and high-precision machining environments.

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

[0004] The control methods of the prior art mainly achieve the chip removal process through the start-stop control of the conveyor belt and the simple start-stop management of the compression device. However, this method only controls according to the collected amount or accumulation of iron chips, ignoring the complex effects of factors such as the shape, density change, and cooling rate of iron chips on the compression efficiency. For example, the prior art cannot adjust the compression pressure in real time to cope with the influence brought by temperature fluctuations and cooling rates during the machining process, resulting in the compression effect being difficult to maintain consistent, and even causing excessive wear of the machine or uneven accumulation of iron chips. In addition, the adjustment of the chip removal path also depends on a fixed control strategy, and fails to consider the real-time change of resistance in the conveying channel, resulting in frequent problems such as blockage and flow deviation 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 ratio of the equipment. Finally, the power adjustment logic in the prior art is relatively simple, and only sets the power through experience, failing to accurately match according to the chip removal demand and compression state, resulting in unnecessary energy waste and unreasonable distribution of mechanical load. These deficiencies directly affect the efficient operation and long-term stability of the chip removal machine. Summary of the Invention

[0005] The object of the present invention is to solve the disadvantages existing in the prior art, and a control method and system for a centralized chip conveyor for a numerically controlled machine tool are proposed.

[0006] To achieve the above object, the present invention adopts the following technical solution: A control method for a centralized chip conveyor for a numerically controlled machine tool, comprising the following steps:

[0007] S1: Obtain chip, compression chamber and ambient temperature data, calculate the chip expansion rate in combination with the expansion coefficient, analyze the influence of the expansion rate and the cooling rate on the density, adjust the compression pressure, and obtain the temperature-compensated compression pressure;

[0008] S2: Based on the temperature-compensated compression pressure, obtain chip morphology data, calculate the optimal initial compression pressure, and adjust the compression pressure according to the deviation to obtain the compression pressure after modal optimization;

[0009] S3: Obtain the flow velocity data of the chips at the nodes of the chip removal conveying channel, calculate the conveying resistance and analyze the resistance distribution, judge the abnormal area and adjust the chip removal flow direction to obtain the adjusted chip removal path;

[0010] 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 change, judge the change point and adjust the chip removal path enabling time to obtain the chip removal path after cycle optimization;

[0011] 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, and integrate the compression pressure after modal optimization to obtain the control result of the chip conveyor for conveying and compression operation.

[0012] As a further solution of the present invention, the temperature-compensated compression pressure includes the chip expansion rate, the cooling rate, and the compressor pressure setting value, the compression pressure after modal optimization includes the optimal initial compression pressure, the compression curve matching value, and the compression pressure adjustment deviation, the adjusted chip removal path includes the conveying resistance value, the resistance distribution condition, and the chip removal flow direction adjustment, the chip removal path after cycle optimization includes the average chip removal flow rate, the chip removal stage change point, and the conveying path enabling time, and the control result of the chip conveyor for conveying and compression operation includes the optimal power output value, the chip removal load matching degree, the conveying motor power setting value, and the compression pressure after modal optimization.

[0013] As a further solution of the present invention, the specific steps for obtaining the temperature-compensated compression pressure are as follows:

[0014] S111: Obtain the temperature sensor data in the compression cavity, including the chip temperature, the compression cavity temperature, and the ambient temperature. Obtain the chip expansion test data for each material during the machining process of the machine tool, extract the reference value of the expansion coefficient for the corresponding material, calculate the product of the chip temperature and the reference value of the expansion coefficient, and obtain the current chip expansion rate;

[0015] S112: Obtain the cooling time of the chips under each temperature condition, and use the formula:

[0016] ;

[0017] Calculate the cooling rate in the current environment ;

[0018] Wherein, represents the initial temperature of the chips, represents the ambient temperature, represents the finally reached temperature, represents the cooling time of the chips, represents the cooling constant;

[0019] S113: Analyze the influence of the current chip expansion rate and the cooling rate on the change of chip density, judge whether it is necessary to adjust the compression pressure, set the pressure value of the compressor on the chip conveyor according to the adjustment requirement, and obtain the compression pressure after temperature compensation.

[0020] As a further solution of the present invention, the step of obtaining the compression pressure after modal optimization is specifically as follows:

[0021] S211: Based on the compression pressure after temperature compensation, obtain the chip morphology data of the laser sensor, respectively detect the distribution of long chips, short chips, and powder chips during the chip removal process, call the flow sensor installed in the chip conveyor to monitor the chip removal speed, and obtain the internal pressure change rate of the compression cavity. Query the corresponding database of chip morphology and compression pressure according to the data, and map the compression curve corresponding to each chip morphology during the chip removal process to obtain the chip morphology compression curve information;

[0022] S212: Based on the chip morphology compression curve information, use the formula:

[0023] ;

[0024] Calculate the optimal initial compression pressure ;

[0025] Wherein, is the specific compression pressure corresponding to the chip morphology is the distribution ratio of the chip morphology ​​is the number of chip morphology types;

[0026] S213: Match the optimal initial compression pressure with the compression curve, analyze the deviation between the optimal initial compression pressure and the compression pressure set value after temperature compensation, and adjust the current compression pressure setting based on the deviation to obtain the compression pressure after modal optimization.

[0027] As a further solution of the present invention, the steps for obtaining the adjusted chip removal path are specifically as follows:

[0028] S311: Obtain the flow velocity data of the chips at the nodes of the chip removal conveying channel, and use the formula:

[0029] ;

[0030] Calculate the conveying resistance at the corresponding conveying channel node of the current chip removal path to obtain the conveying resistance distribution information;

[0031] Among them, is the friction coefficient of the conveying channel, is the total length of the conveying channel, is the chip bulk density, is the pipeline diameter of the conveying channel;

[0032] S312: Based on the conveying resistance distribution information, use the formula:

[0033] ;

[0034] Calculate the resistance change gradient of the conveying channel node. If the resistance change gradient exceeds the set abnormal threshold, it is determined that there is a resistance abnormality in the target area, and the chip removal path is adjusted by adjusting the abnormal area to obtain the adjusted chip removal path;

[0035] Among them, is the pipeline position at the conveying channel node and represents the next monitoring node along the conveying path direction.

[0036] As a further solution of the present invention, the steps for obtaining the chip removal path after cycle optimization are specifically as follows:

[0037] S411: Based on the adjusted chip removal path, obtain the machine tool processing task records, including the task time interval and the cutting material type, and use the formula:

[0038] ;

[0039] Calculate the average chip removal flow rate of each task ;

[0040] Wherein, represents the sampling time interval, is the total duration of the task , represents the instantaneous chip removal flow rate of the th task at time ;

[0041] S412: Based on the average chip removal flow rate of each type of task , use the formula:

[0042] ;

[0043] Calculate the periodic fluctuation coefficient of the task , compare the periodic fluctuation coefficient with the preset fluctuation threshold, and optimize and adjust according to the comparison result to obtain the chip removal path with optimized period;

[0044] Wherein, , are the maximum and minimum instantaneous chip removal flow rates of the task .

[0045] As a further solution of the present invention, the step of obtaining the control result of the chip conveyor's transportation and compression operation is specifically as follows:

[0046] S511: Based on the chip removal path with optimized period, set the optimal power output value of the conveyor motor according to the real-time resistance of each path to obtain the analysis result of the optimal motor power;

[0047] S512: Based on the analysis result of the optimal motor power, judge the matching degree between the optimal power output value and the current chip removal load, adjust the power of the conveyor motor according to the matching degree, and integrate the optimized compression pressure in the mode to obtain the control result of the chip conveyor's transportation and compression operation.

[0048] A control system for a centralized chip conveyor for a numerically controlled machine tool, the control system for the centralized chip conveyor for a numerically controlled machine tool is used to execute the above control method for the centralized chip conveyor for a numerically controlled machine tool, and the system includes:

[0049] The chip expansion control module obtains the data of chips, the compression chamber and the ambient temperature, calculates the chip expansion rate in combination with the expansion coefficient, analyzes the influence of the expansion rate and the cooling rate on the density, and adjusts the compression pressure to generate the temperature-compensated compression pressure;

[0050] Based on the compression pressure after temperature compensation, the compression pressure optimization module obtains chip morphology data, calculates the optimal initial compression pressure, adjusts the compression pressure according to the deviation, and generates the compression pressure after modal optimization;

[0051] Based on the compression pressure after modal optimization, the chip removal path adjustment module obtains the flow velocity data of the chips at the nodes of the chip removal and conveying channel, calculates the conveying resistance and analyzes the resistance distribution, judges the abnormal area and adjusts the chip removal flow direction to obtain the adjusted chip removal path;

[0052] Based on the adjusted chip removal path, the periodic change analysis module obtains the machine tool processing task record, calculates the average chip removal flow rate, analyzes the periodic change, judges the change point and adjusts the chip removal path enabling time to obtain the chip removal path after cycle optimization;

[0053] Based on the chip removal path after cycle optimization, the conveying power adjustment module sets the optimal power of the conveying motor, analyzes the matching degree and adjusts the power, and integrates the compression pressure after modal optimization to obtain the control result of the chip removal machine for conveying and compression operation.

[0054] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0055] 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 precisely. By combining the expansion coefficient and the cooling time, not only the temperature fluctuation is monitored in real time, but also the adjustment can be made according to the deviation of the chip morphology and the compression pressure, ensuring 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 operation efficiency. In addition, by dynamically calculating the chip removal flow velocity, conveying resistance and periodic fluctuation, the chip removal path can be optimized in real time during the processing, automatically judge and adjust the chip removal enabling time and flow direction, reduce the blockage and abnormal phenomena during the chip removal process, and improve the stability and working efficiency of the equipment. Finally, through power adjustment, the load matching degree of the conveying motor and the compressor is ensured, the overall power consumption of the chip removal machine is more reasonably controlled, and the energy consumption is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 is a schematic diagram of the working process of the present invention;

[0057] Figure 2 is a flowchart of obtaining the compression pressure after temperature compensation of the present invention;

[0058] Figure 3 is a flowchart of obtaining the compression pressure after modal optimization of the present invention;

[0059] Figure 4 Flow chart for obtaining the adjusted chip removal path in the present invention;

[0060] Figure 5 Flow chart for obtaining the chip removal path with optimized cycle in the present invention;

[0061] Figure 6 Flow chart for obtaining the control result of the conveying and compressing operation of the chip conveyor in the present invention. Detailed implementation manners

[0062] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0063] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the accompanying 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 thus should not be construed as limiting the present invention. In addition, in the description of the present invention, "a plurality of" means two or more unless otherwise specifically defined.

[0064] Please refer to Figure 1 , the present invention provides a technical solution: a control method for a centralized chip conveyor for a numerically controlled machine tool, including the following steps:

[0065] S1: Obtain data on chips, compression chambers and ambient temperature, calculate the chip expansion rate in combination with the expansion coefficient, analyze the influence of the expansion rate and the cooling rate on the density, and adjust the compression pressure to obtain the temperature-compensated compression pressure;

[0066] S2: Based on the temperature-compensated compression pressure, obtain chip morphology data, calculate the optimal initial compression pressure, and adjust the compression pressure according to the deviation to obtain the compression pressure with optimized mode;

[0067] S3: Obtain the flow velocity data of the chips at the nodes of the chip removal conveying channel, calculate the conveying resistance and analyze the resistance distribution, judge the abnormal area and adjust the chip removal flow direction to obtain the adjusted chip removal path;

[0068] 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 change, judge the change point and adjust the chip removal path activation time to obtain the chip removal path with optimized cycle;

[0069] S5: Based on the chip evacuation path optimized by cycle, set the optimal power of the conveying motor, analyze the matching degree and adjust the power, integrate the compression pressure optimized by mode, and obtain the control results of the conveying and compression operation of the chip evacuator;

[0070] The compression pressure after temperature compensation includes the chip expansion rate, the cooling rate, and the compressor pressure set value. The compression pressure optimized by mode includes the optimal initial compression pressure, the compression curve matching value, and the compression pressure adjustment deviation. The adjusted chip evacuation path includes the conveying resistance value, the resistance distribution, and the chip evacuation flow direction adjustment. The chip evacuation path optimized by cycle includes the average chip evacuation flow rate, the change point of the chip evacuation stage, and the conveying path activation time. The control results of the conveying and compression operation of the chip evacuator include the optimal power output value, the chip evacuation load matching degree, the conveying motor power set value, and the compression pressure optimized by mode.

[0071] Please refer to Figure 2 , and the specific steps for obtaining the compression pressure after temperature compensation are as follows:

[0072] S111: Obtain the temperature sensor data in the compression chamber, including the chip temperature, the compression chamber temperature, and the ambient temperature. Obtain the chip expansion test data of each material during the machine tool processing, extract the reference value of the expansion coefficient of the corresponding material, and calculate the product of the chip temperature and the reference value of the expansion coefficient to obtain the current chip expansion rate;

[0073] Obtain the temperature sensor data in the compression chamber, including the chip temperature, the compression chamber temperature, and the ambient temperature. Measure the chip temperature at different time points during the machine tool processing respectively is 700K, the compression chamber temperature is 320K, and the ambient temperature is 300K. These data are stored through the data recording module and used for subsequent calculations. Obtain the chip expansion test data of each material during the machine tool processing. For example, for the chips of 45# steel, the reference value of the expansion coefficient measured in the experiment is K , this value is obtained from high-temperature experiment measurements and recorded in the material expansion coefficient database. After calling this value, calculate the product of the chip temperature and the reference value of the expansion coefficient. The calculation process is as follows: , represents the current chip expansion rate, dimensionless; represents the reference value of the material expansion coefficient, with the unit of K ; represents the temperature of the chips, with the unit of K; represents the ambient temperature, with the unit of K. Substitute the values: , and calculate that the current chip expansion rate is 0.0048.

[0074] S112: Obtain the cooling time of the debris under each temperature condition using the formula:

[0075] ;

[0076] Calculate the cooling rate under the current environment ;

[0077] where, represents the natural logarithm function, which is used to calculate the logarithm of the temperature ratio. This helps to linearize the exponential cooling process and make the calculation results more applicable to linear analysis. represents the initial temperature of the debris, in the unit of (Kelvin). This temperature is obtained by measuring immediately after the debris is generated using an infrared thermal imager. represents the ambient temperature, also in the unit of . This temperature is continuously monitored by the temperature sensors installed in the workshop. represents the finally reached temperature, also in the unit of . This temperature is obtained by measuring the debris temperature again using an infrared thermal imager after the set cooling time. represents the cooling time of the debris, in the unit of (seconds), which is the time interval set before the experiment, for example, the time from the generation of the debris until the temperature is measured again. represents the cooling constant, which is a dimensionless parameter that comprehensively considers the heat transfer properties of the material and the efficiency of the cooling medium. This constant is determined through previous thermodynamics experiments, in which the cooling efficiencies under different combinations of materials and cooling media were compared to obtain an average value.

[0078] Set the initial temperature , the ambient temperature , the final temperature , the cooling time , the experimentally measured cooling constant , substitute into the formula for calculation: , the calculated cooling rate of the debris is 0.1733 s .

[0079] S113: Analyze the influence of the current debris expansion rate and the cooling rate on the change in debris density, determine whether it is necessary to adjust the compression pressure, and set the pressure value of the compressor on the chip discharger according to the adjustment requirement to obtain the compression pressure after temperature compensation;

[0080] 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 compare and calculate according to the following steps: Calculate the debris density after cooling: According to the formula for the influence of thermal expansion on density: , where, is the debris density after cooling, is the initial density of the debris, is the expansion rate of the debris. It represents the density decrease caused by the volume expansion of the debris under temperature change. Correlation between cooling rate and density change: Since the cooling rate affects the duration of the thermal expansion effect, set a density change influence factor , and calculate its corrected density: , where, is the debris density corrected by the cooling rate, is the experimentally determined cooling influence coefficient (used to adjust the influence of the cooling rate on density). Judge the density decrease amount and adjust the compression pressure: , if kg / m , then adjust the compression pressure, otherwise keep the current setting.

[0081] Set the initial density kg / m , the calculated debris expansion rate , the cooling rate s , the experimentally measured cooling rate influence factor , then: Calculate the debris density after cooling: . Calculate the density corrected by the cooling rate: . Calculate the density decrease amount: . Since kg / m , it is necessary to adjust the compression pressure. According to 's change trend, if the density decrease is significant (for example, more than 50 kg / m ), it means that the debris expansion is large, which has a great impact on the debris density in the compression chamber, resulting in a decrease in chip removal efficiency. Excessive debris may have a negative impact on the cooling effect. Therefore, it is necessary to increase the compression pressure to counteract the influence of expansion and restore an appropriate density. The adjustment range of the compression pressure is usually estimated according to the debris expansion rate and the density corrected by the cooling rate. According to the known experimental data and formula, set that a certain value of compression pressure needs to be increased for every 1 kg / m of density decrease. Assume that 0.5 bar of compression pressure adjustment amount needs to be increased for every 1 kg / m of decrease, then the adjusted compression pressure can be calculated by the following formula: , where, is the compression pressure of the current compressor, is the coefficient obtained from experiments (e.g., 0.5 bar / kg / m ), and is the calculated density decrease. In actual operation, the operator adjusts the pressure setting on the compressor according to the density change and the calculation result. During operation, the increase in the compressor pressure should be kept stable to avoid over-adjustment resulting in excessive compression of the chips or uneven compression. By gradually adjusting, it can be ensured that the density of the chips is maintained within a reasonable range while maintaining the stability and chip removal efficiency during the processing. For example, assume the current compression pressure bar, and the calculated density decrease kg / m . Then, according to the above adjustment formula, the adjustment amount of the compression pressure is: . By this method, the operator can adjust the compression pressure of the compressor to 159 bar to ensure the compression effect after the chips expand and obtain the compression pressure after temperature compensation.

[0082] Please refer to Figure 3 for the specific steps to obtain the compression pressure after modal optimization:

[0083] S211: Based on the compression pressure after temperature compensation, obtain the chip morphology data of the laser sensor, respectively detect the distribution of long chips, short chips, and powder chips during the chip removal process, call the flow sensor installed in the chip removal machine to monitor the chip removal speed, and obtain the internal pressure change rate of the compression chamber. According to the data, query the corresponding database of chip morphology and compression pressure, map the compression curve corresponding to each chip morphology during the chip removal process, and obtain the chip morphology compression curve information;

[0084] Obtain chip morphology data from optical / laser sensors, including long chips, short chips, and powder chips, and record the proportion information of various types of chips. Long chips are long and curved and prone to entanglement. Short chips are in the form of broken particles, and powder chips are in a state of accumulation of tiny particles. These morphologies affect the filling density and force distribution during the compression process. Obtain the data of the flow sensor on the chip discharge conveyor to detect the chip discharge flow rate per unit time. Assume the current chip discharge speed is 0.015 m³ / s, and obtain the pressure change rate in the compression chamber. Set the pressure change rate within the current detection period 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, due to their strong elastic recovery characteristics, usually show a relatively high initial pressure requirement in their compression curves. Short chips, due to their broken particle morphology, can be effectively compressed at lower pressures. Powder chips, due to their relatively large packing density, are easy to fill at low pressures but tend to form a hardened structure at high pressures. 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.

[0085] S212: Based on the chip morphology compression curve information, use the formula:

[0086] ;

[0087] Calculate the optimal initial compression pressure ;

[0088] where, is the specific compression pressure corresponding to the chip morphology , with the unit of Pa. Look up the experimental compression pressure data of different chip types in the database. For example, long chips are 500,000 Pa, short chips are 300,000 Pa, and powder chips are 100,000 Pa. These values are determined through experiments. Measure the density change curves of each chip morphology under different pressure conditions and extract the key point data. is the distribution ratio of the chip morphology during the current chip discharge process, dimensionless. It is calculated by the optical / laser sensor detecting the chip morphology and calculating its proportion. For example, long chips are 60%, short chips are 30%, and powder chips are 10%. These proportions are obtained through real-time monitoring and calculated based on the chip volume entering the compression chamber per unit time. is the number of types of chip morphologies, usually 3, corresponding to long chips, short chips, and powder chips, and can be extended according to the actual situation.

[0089] Substitute the above values: , and the calculated optimal initial compression pressure is 400,000 Pa.

[0090] 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.

[0091] 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;

[0092] 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 Set relatively low, usually between 0.5 - 0.7, to prevent excessive energy consumption caused by over - adjustment of pressure. System stability requirements: High - stability requirements (high - precision machining environment): If the system has high requirements for the stability of chip - removal pressure, such as in a numerically controlled machine tool for high - precision machining, it is necessary to prevent the impact caused by too - fast pressure adjustment, Set between 0.5 - 0.7 to ensure the stable operation of the system. Low - stability requirements (ordinary machining or rough - machining environment): If the machining environment allows a certain range of pressure fluctuations, then it is possible to appropriately increase , 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, the adjustment ratio coefficient needs to be determined by comprehensively considering the response speed of the chip - removal system, the compression characteristics of chip types, and the system stability requirements. Determine a reasonable range through experimental tests and adjust according to machining requirements. For example, if the pressure response speed of the system is 1.5 MPa / s, mainly dealing with short chips, and the machining environment requires high stability, then is set near 0.6; if the system response speed is slow (<1 MPa / s), mainly dealing with long chips and the machining environment allows pressure fluctuations, then is set around 0.85 to enhance the amplitude of pressure adjustment. is the adjusted compression pressure, with the unit of Pa, used to control the final pressure setting of the compressor. Since the error exceeds the threshold, the system executes the compressor pressure adjustment. Assuming the adjustment ratio coefficient is 0.8, then the adjusted compression pressure: ; The adjusted compression pressure is set to 396,000 Pa to obtain the optimized compression pressure after modal optimization.

[0093] Please refer to Figure 4 , the specific steps for obtaining the adjusted chip - removal path are as follows:

[0094] S311: Obtain the flow velocity data of the chips at the nodes of the chip - removal conveying channel, using the formula:

[0095] ;

[0096] Calculate the conveying resistance at the corresponding conveying - channel node of the current chip - removal path to obtain the conveying - resistance distribution information;

[0097] Among them, is the friction coefficient of the conveying channel (dimensionless), determined by experiments, and derived by measuring the pressure - drop data under known flow rates. is the total length (m) of the conveying channel, provided by the design parameters of the conveying channel. is the chip packing density (kg / m³), which is determined experimentally and obtained by calculating the mass of a certain volume of chips. For example, if the mass of 5L (0.005m³) of chips is measured to be 4kg, then kg / m³. is the chip flow velocity (m / s) at the node of the conveying channel, which is measured by a flow velocity sensor. is the pipe diameter (m) of the conveying channel, which is provided by the physical design of the conveying system.

[0098] Substitute the flow velocity data of the three nodes respectively m / s, m / s, m / s to calculate the conveying resistance:

[0099] ;

[0100] ;

[0101] ;

[0102] The calculated conveying resistance represents the pressure loss caused by flow friction at different monitoring nodes. Among them, the conveying resistance of the first node is the highest, reaching 1152Pa, the resistance of the second node drops to 512Pa, and the resistance of the third node further decreases to 128Pa. This indicates that there are significant changes in the energy loss during the chip removal process on the conveying path, and the conveying resistance distribution data is obtained.

[0103] S312: Based on the conveying resistance distribution information, use the formula:

[0104] ;

[0105] Calculate the resistance change gradient of the conveying channel node , if the resistance change gradient exceeds the set abnormal threshold, it is determined that there is a resistance abnormality in the target area, and the chip removal path after adjustment is obtained by adjusting the abnormal area;

[0106] Among them, is the pipe position (m) at the node of the conveying channel, which is provided by the design parameters of the conveying channel, represents the next monitoring node along the conveying path direction.

[0107] Set the abnormal threshold Pa / m, and calculate to obtain:

[0108] ;

[0109] ;

[0110] The calculation results show that the resistance gradient of the first monitoring section is -128 Pa / 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 discharge flow velocity. The resistance gradient of the second monitoring section is -76.8 Pa / 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 discharge flow direction, optimize the chip conveying path, use an auxiliary chip discharge path for dredging, and calculate the adjusted flow distribution: . Among them, is the volume flow rate (m³ / s) at the adjusted conveying channel node , which is calculated and represents the chip conveying flow rate after adjusting the chip discharge path. is the volume flow rate (m³ / s) at the original conveying channel node , is the diversion coefficient (dimensionless), which is used to describe the reallocation ratio of the chip discharge flow rate. The larger is, the greater the adjusted flow rate ratio is, and the more chip discharge is diverted to other paths. The setting principle is as follows: when the conveying resistance gradient is too large, that is, the chip discharge pressure loss in a certain section is relatively high, resulting in an increased risk of blockage, should be increased to reduce the flow rate of this path. Usually, the setting range is 0.2 ≤ ≤ 0.5. When the conveying capacity of the auxiliary path is strong (large pipe diameter, low friction coefficient), can take a higher value, otherwise take a lower value. For example, in actual measurement, if the resistance in a certain area reaches 130 Pa / m, which is higher than the threshold , then can be set to enhance the diversion ability.

[0111] Substitute the data:

[0112] ;

[0113] ;

[0114] The calculation results show that after the flow rate adjustment, the chip discharge flow rate of the first conveying path decreases from 0.036 m³ / s to 0.0252 m³ / s, and the chip discharge flow rate of the second conveying path increases from 0.024 m³ / s to 0.0348 m³ / s. That is, part of the chip flow rate is diverted to the conveying path with less resistance, optimizing the overall chip discharge path, alleviating the pressure loss in the high-resistance area, and obtaining the adjusted chip discharge path.

[0115] Please refer to Figure 5, the steps for obtaining the chip removal path after cycle optimization are specifically as follows:

[0116] 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, and use the formula:

[0117] ;

[0118] Calculate the average chip removal flow rate for each task ;

[0119] Among them, represents the sampling time interval, with the unit of s, and is used for numerical integration with discrete time steps. is the total duration of task . represents the th task's instantaneous chip removal flow rate at time .

[0120] Set the instantaneous flow rate data for different tasks as follows:

[0121] Task 1: m³ / s, with a duration of hours;

[0122] Task 2: m³ / s, with a duration of hours;

[0123] Task 3: m³ / s, with a duration of hours.

[0124] Calculate the average chip removal flow rate for each task:

[0125] ;

[0126] ;

[0127] ;

[0128] 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, obtaining the average chip removal flow rate for each task.

[0129] S412: Based on the average chip removal flow rate for each task, use the formula:

[0130] ;

[0131] Calculate the periodic fluctuation coefficient of task ​ ;

[0132] Among them, 、 are the maximum and minimum instantaneous chip removal flow rates of the task, in m³ / s, and are directly recorded by the data acquisition system.

[0133] Calculated in combination with the parameters of S411:

[0134] ;

[0135] ;

[0136] ;

[0137] If , it is considered that the task cycle fluctuates greatly, and the chip removal path needs to be adjusted. Set the fluctuation threshold . It is judged that tasks 1 and 3 need to optimize the enabling time of the conveying path. Adjust the switching time of the conveying paths of tasks 1 and 3, and adopt the optimization adjustment strategy: , among which, represents the time adjustment coefficient of the task, and the setting method is as follows: when the task cycle fluctuates greatly ( ), the adjustment coefficient takes a larger value (510 min) to make the path adjustment more obvious; when the task cycle fluctuates slightly ( ), the adjustment coefficient takes (35 min) to moderately optimize the path; when the task cycle fluctuates low ( ), keep the path unchanged without adjustment.

[0138] Set min for tasks 1 and 3, min, and calculate:

[0139] ;

[0140] ;

[0141] Among them, is the original conveying path enabling time of task , in min, and is obtained from the task scheduling plan; is the optimized conveying path enabling time of task , in min. The calculation results show that the conveying path enabling time of task 1 needs to be adjusted by 0.86 min, and that of task 3 by 0.85 min, to obtain the chip removal path with optimized cycle.

[0142] Please refer to​Figure 6 The steps for obtaining the control results of the chip conveyor's transportation and compression operations are specifically as follows:

[0143] S511: Based on the chip evacuation path optimized by the cycle, according to the real-time resistance of each path, set the optimal power output value of the conveyor belt motor to obtain the analysis result of the motor's optimal power;

[0144] First, obtain the current resistance data of each path through the pressure sensors installed along the transportation channel. When obtaining the resistance data, parameters such as channel length, flow rate, and hydrodynamic effects should be considered, and historical data should be combined for comparison to confirm the stability of the resistance. The basis for judging the resistance needs to refer to the cross-sectional area of the channel and the pressure change rate per unit time. Set a reference 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 determined to be in a resistance fluctuation state; if it is greater than 0.2 kPa / s, it is regarded as an abnormal resistance and power adjustment is required. When setting the optimal power output value of the conveyor motor, a power mapping table needs to be established based on different types of chip types. The establishment of the mapping table needs to be based on the density, particle diameter, flow characteristics of the chips, and the transportation volume per unit time. If the chip density is in the range of 500 - 700 kg / m³ and the transportation volume per unit time is in 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 transportation volume exceeds 3 kg / s, the power setting value needs to be increased by 10% - 20% to ensure transportation stability. If the density is below 500 kg / m³ and the transportation volume is less than 2 kg / s, the power setting value can be reduced by 5% - 10%. On this basis, dynamic adjustment is performed according to the real-time resistance data. If the resistance is within the stable range, the current power output is maintained. If the resistance fluctuates, the adjustment amplitude is set based on the resistance change rate. For example, for every 0.05 kPa / s increase in the resistance volatility rate, the power is increased by 5%, with a maximum increase not exceeding 30% of the rated power. Finally, set the optimal power output value for each path in the transportation control system and store it as an operating parameter in the system.

[0145] S512: Based on the analysis result of the motor's optimal power, judge the matching degree between the optimal power output value and the current chip evacuation load, adjust the power of the conveyor motor according to the matching degree, and integrate the compression pressure optimized by the mode to obtain the control results of the chip conveyor's transportation and compression operations;

[0146] First, call the current operating data of the conveyor motor, including real-time power consumption, rotational speed, and load curve, calculate the power matching degree under the current load. The judgment of the matching degree is 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 within the range of 95% - 105%, it is considered that the current power output meets the load demand. 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 amount 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 means that the power is excessive, and the reduction amount is set according to the excess ratio. For example, if the matching degree is 110%, the power is reduced by 5%. During the adjustment process, the modal optimization pressure of the compression system needs to be combined. If the compression system pressure is higher than 10 MPa, when adjusting the power of the conveyor motor, the adjustment range is appropriately reduced and controlled within the range of **3% - 8%** to prevent unstable conveying caused by power fluctuations. In addition, during the power adjustment process, the adjusted conveying efficiency needs to be calculated synchronously. Set the efficiency threshold. If the adjusted conveying efficiency is lower than 85%, recalculate the matching degree and reset the adjustment range until both the matching degree and the conveying efficiency are within a reasonable range. Finally, by adjusting the power of the conveyor motor and integrating the compression pressure, the operation control results of the chip conveyor and compression are obtained.

[0147] A control system for a centralized chip conveyor used in a numerical control machine tool. The control system for the centralized chip conveyor used in a numerical control machine tool is used to execute the above control method for the centralized chip conveyor used in a numerical control machine tool. The system includes:

[0148] 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 the cooling rate on the density, and adjusts the compression pressure to generate the compression pressure after temperature compensation.

[0149] The compression pressure optimization module obtains the chip morphology data based on the compression pressure after temperature compensation, calculates the optimal initial compression pressure, and adjusts the compression pressure according to the deviation to generate the compression pressure after modal optimization.

[0150] The chip discharge path adjustment module obtains the flow velocity data of the chips at the nodes of the chip discharge conveying channel based on the compression pressure after modal optimization, calculates the conveying resistance, analyzes the resistance distribution, judges the abnormal area, and adjusts the chip discharge flow direction to obtain the adjusted chip discharge path.

[0151] The periodic change analysis module obtains the machine tool processing task record based on the adjusted chip discharge path, calculates the average chip discharge flow rate, analyzes the periodic change, judges the change point, and adjusts the chip discharge path activation time to obtain the chip discharge path after cycle optimization.

[0152] Based on the chip removal path optimized by the cycle, the conveying power adjustment module sets the optimal power of the conveying motor, analyzes the matching degree and adjusts the power, integrates the compression pressure optimized by the mode, and obtains the control results of the conveying and compression operation of the chip conveyor.

[0153] The above are only the preferred embodiments of the present invention, and there are no other forms of limitations on the present invention. Any person skilled in the art may use the technical content disclosed above to make changes or modifications into equivalent embodiments with equivalent changes and apply them to other fields. However, as long as the technical solution content of the present invention is not departed from, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall 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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