Thermal deformation suppression system and method

Abstract

The invention provides a thermal deformation suppression system and method, and relates to the technical field of precision machining equipment, the system comprises a frequency conversion oil cooling module with a double-circulation cooling module, and a thermal compensation module; the thermal deformation suppression method comprises the following steps: acquiring temperature data of different parts of a to-be-cooled component in real time; based on the obtained temperature data, the cooling output capacity of the variable frequency oil cooling module is dynamically adjusted; the thermal compensation module obtains the thermal elongation of the to-be-cooled component in real time; and based on the obtained thermal elongation, the cooling output capacity of the variable frequency oil cooling module is adjusted, meanwhile, based on the thermal elongation, a compensation value is calculated and written into a servo instruction, and the machining coordinates of the to-be-cooled component are dynamically compensated. The temperature control precision is + / -0.1 DEG C, the thermal deformation compensation precision is + / -1mu m, and the yield is improved to 99.5%.

Description

Technical Field

[0001] This invention relates to the field of precision machining equipment technology, and in particular to a spindle thermal deformation suppression system based on variable frequency oil cooling and thermal compensation, and a method for thermal compensation using the suppression system. Background Technology

[0002] In high-speed, high-precision machine tool machining, spindle thermal deformation is a core factor affecting machining accuracy and stability. Traditional cooling systems generally use fixed-frequency oil coolers, which cannot respond to temperature fluctuations, resulting in low temperature control accuracy (±1.5℃), local overheating exceeding the limit by more than 5℃, and accelerated component aging and failure. Thermal compensation technology relies on static thermal models, with compensation response delays exceeding 200ms and cumulative errors reaching ±5μm. Furthermore, the cooling system and compensation mechanism operate independently, lacking data coordination and dynamic linkage, and cannot suppress deformation from the heat source input end, only passively correcting the results. This leads to large fluctuations in machining accuracy, high equipment maintenance costs, and a yield rate that has remained around 92% for a long time.

[0003] Therefore, there is an urgent need for a system that can achieve source suppression and real-time dynamic compensation to meet the stringent requirements of modern high-precision machining for stability and reliability. Summary of the Invention

[0004] The purpose of this invention is to provide a spindle thermal deformation synergistic suppression system based on variable frequency oil cooling dual-cycle cooling and dynamic thermal compensation, and a method for thermal compensation using this suppression system, so as to solve the above-mentioned technical problems existing in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: The present invention provides a method for suppressing thermal deformation, comprising the following steps: Real-time acquisition of temperature data from different parts of the component to be cooled; Based on the acquired temperature data, the cooling output capacity of the variable frequency oil cooling module is dynamically adjusted; The thermal compensation module acquires the thermal elongation of the component to be cooled in real time. Based on the acquired thermal expansion, the cooling output capacity of the variable frequency oil cooling module is adjusted. At the same time, based on the thermal expansion, the compensation value is calculated and written into the servo command to dynamically compensate the machining coordinates of the component to be cooled.

[0006] This invention collects temperature data from different parts of the component to be cooled in real time, achieving full-area temperature sensing and avoiding the limitations of single-point temperature measurement. It accurately grasps the heat distribution state, providing a true and reliable data foundation for subsequent cooling adjustments, reducing cooling control deviations caused by inaccurate temperature measurements at the source. Through temperature data, the cooling output capacity of the variable frequency oil cooling module is dynamically adjusted, abandoning the traditional constant cooling mode. Cooling intensity is adaptively adjusted in real time according to temperature, avoiding energy waste from overcooling and thermal deformation caused by overheating. This balances cooling efficiency and temperature control accuracy, reducing energy consumption. The thermal compensation module obtains the thermal elongation of the component to be cooled in real time, directly monitoring key indicators of thermal deformation. This overcomes the error of indirectly estimating deformation based solely on temperature, obtaining the true deformation amount. This provides a precise basis for coordinate compensation and cooling control, improving the reliability of deformation control. It forms a dual suppression mechanism of cooling temperature control and coordinate compensation, reducing thermal deformation at the source and correcting machining coordinates in real time for existing deformation, thus doubly ensuring machining accuracy and significantly reducing the impact of thermal deformation on machining precision.

[0007] As a further improvement of the present invention, the variable frequency oil cooling module includes a first cooling module for cooling a first position of the component to be cooled and a second cooling module for cooling a second position of the component to be cooled; the dynamic adjustment of the cooling output capability of the variable frequency oil cooling module based on the acquired temperature data includes: Obtain the maximum temperature value inside the component to be cooled; Determine the range containing the maximum temperature value; Adjust the opening degree of the regulating valve in the first cooling module based on different ranges; Based on the obtained maximum temperature value, the variable frequency oil pump of the second cooling module is controlled to run at the preset corresponding output speed.

[0008] Through the above controls, independent cooling is achieved in different zones, allowing for precise regulation based on the varying heat loads of different parts of the component. This avoids localized insufficient or excessive cooling caused by uniform cooling across the entire area, improving temperature control uniformity. Using the highest temperature as the core control basis, it identifies key overheating points of the component and adjusts in stages according to temperature ranges. The logic is simple and the response is highly efficient, quickly matching the corresponding cooling intensity and avoiding adjustment lag.

[0009] As a further improvement of the present invention, adjusting the opening degree of the regulating valve in the first cooling module based on different intervals includes: When the maximum temperature value is in the low temperature range, adjust the regulating valve in the first cooling module to operate at a small opening. When the maximum temperature value is in the medium temperature range, adjust the regulating valve in the first cooling module to open to the medium degree of operation. When the maximum temperature value is in the high temperature range, adjust the regulating valve in the first cooling module to open to the maximum degree of operation.

[0010] This invention achieves stepped, precise temperature control, low-temperature, low-consumption cooling, and high-temperature enhanced cooling, reducing energy waste while ensuring effective temperature control and adapting to different heat load conditions.

[0011] As a further improvement of the present invention, after adjusting the opening degree of the regulating valve in the first cooling module based on different intervals, the method further includes: Obtain the real-time maximum temperature value inside the component to be cooled again; Determine whether the real-time maximum temperature value has reached the preset temperature value; When the determination is yes, the opening of the regulating valve in the first cooling module is gradually reduced.

[0012] After the temperature reaches the target, the opening of the regulating valve is gradually reduced to avoid a sudden valve closure that could cause a temperature rebound. This achieves a smooth cooling transition, maintains stable component temperature, and prevents secondary thermal deformation caused by sudden temperature changes.

[0013] As a further improvement of the present invention, after determining that the opening of the regulating valve in the first cooling module is gradually reduced, the method further includes: Obtain the real-time maximum temperature value inside the component to be cooled again; The real-time maximum temperature value is compared with the preset reference temperature value to obtain the average rate of temperature change over a set time period. Based on the obtained average temperature change rate, the opening degree of the regulating valve in the first cooling module is set to adjust the amplitude.

[0014] This invention calculates the average rate of temperature change to set the opening of the amplitude adjustment valve, upgrading from step adjustment to closed-loop fine adjustment. It dynamically corrects the cooling intensity according to the rate of temperature change, achieving precise and stable temperature control, reducing the temperature fluctuation range, and further suppressing thermal deformation.

[0015] As a further improvement of the present invention, after controlling the second cooling module to operate at a preset corresponding output frequency based on the maximum temperature value, the method further includes: Obtain the second circuit oil pressure within the second cooling module; When the second return oil pressure is lower than the second preset threshold, an alarm is triggered and the output speed of the variable frequency oil pump of the second cooling module is increased.

[0016] This invention controls the speed of the variable frequency oil pump of the second cooling module according to the maximum temperature value. The second cooling module adopts direct speed control, which results in faster response and more linear cooling output.

[0017] As a further improvement of the present invention, after obtaining the maximum temperature value inside the component to be cooled, the method further includes: Obtain the first circuit oil pressure within the first cooling module; When the first return oil pressure is lower than the first preset threshold, the output speed of the variable frequency oil pump of the first cooling module is increased.

[0018] This invention monitors the oil pressure in the first circuit, alarms when the oil pressure is too low and increases the oil pump speed, monitors the operating status of the cooling circuit in real time, promptly detects faults such as oil circuit blockage and leakage, avoids cooling failure due to insufficient oil pressure, and automatically adjusts the speed to ensure cooling continuity, improves system stability and safety, and complements the valve opening adjustment of the first cooling module to improve the overall cooling system control flexibility.

[0019] This invention provides a thermal deformation suppression system for performing the thermal compensation method, the thermal deformation suppression system comprising: The variable frequency oil cooling module can dynamically adjust the cooling output capacity based on the real-time temperature data of the component to be cooled. A thermal compensation module is network-connected to the variable frequency oil cooling module to dynamically correct the processing coordinates based on the real-time temperature data obtained by the variable frequency oil cooling module, and to dynamically adjust the cooling output capacity of the variable frequency oil cooling module based on the thermal elongation of the component to be cooled.

[0020] The thermal deformation suppression system of this invention includes a variable frequency oil cooling module and a thermal compensation module, which are connected in a network for coordinated control. This enables data exchange and linkage control between temperature control and deformation compensation, breaking the limitations of a single module working independently and forming an integrated thermal deformation suppression system. The control accuracy and response speed are significantly improved.

[0021] As a further improvement of the present invention, the variable frequency oil cooling module is a dual-cycle cooling module, including a first cooling module and a second cooling module independently set at different positions of the component to be cooled.

[0022] This invention features dual-loop independent operation without interference, allowing for individual adjustment based on the heat dissipation needs of different areas of the component, resulting in more comprehensive cooling coverage. Furthermore, a failure in one loop does not affect the other loop, enhancing system redundancy.

[0023] As a further improvement of the present invention, the first cooling module includes a first variable frequency oil cooling pump, a first temperature sensor, a first pressure sensor, a first cooling circuit, and a regulating valve. The first cooling circuit includes a spiral cooling channel embedded in the component to be cooled. The regulating valve is disposed between the first variable frequency oil cooling pump and the first cooling circuit.

[0024] The present invention features a spiral embedded channel that increases the cooling contact area, resulting in uniform and efficient cooling; a regulating valve precisely controls the flow rate, and multiple sensors enable full monitoring of temperature and pressure, achieving closed-loop and precise cooling control.

[0025] As a further improvement of the present invention, the second cooling module includes a second variable frequency oil cooling pump, a second temperature sensor, a second cooling circuit and a second pressure sensor; the second cooling circuit includes a plurality of spray elements spaced apart along the circumferential direction of the component to be cooled.

[0026] The spray-type cooling system of this invention covers the outer periphery of the component, providing fast and wide-ranging cooling. It works in conjunction with the embedded cooling in the first cooling module to form a synergistic cooling effect, further improving the overall cooling efficiency and uniformity.

[0027] As a further improvement of the present invention, the thermal compensation module includes a laser interferometer and a numerical control compensation system; the laser interferometer is signal-connected to the numerical control compensation system.

[0028] This invention provides a laser interferometer for high-precision measurement of thermal elongation with minimal measurement error; the CNC compensation system directly incorporates servo commands, ensuring real-time and accurate compensation response, perfectly suited for high-precision machining scenarios. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a partial control flowchart of the variable frequency oil cooling module in the thermal deformation suppression method of the present invention; Figure 2 This is another part of the control flowchart regarding the variable frequency oil cooling module in the thermal deformation suppression method of this invention; Figure 3 This is a control flowchart of the thermal compensation module in the thermal deformation suppression method of the present invention; Figure 4 This is a flowchart of the collaborative control logic of the thermal deformation suppression system of the present invention; Figure 5 This is a schematic diagram of the thermal deformation suppression system of the present invention; Figure 6 This is a layout diagram of the dual-circulation cooling loop in the thermal deformation suppression system of the present invention; Figure 7 yes Figure 6 Enlarged view of part A in the middle; Figure 8 This is a schematic diagram of the spray coverage of the bearing cooling circuit in the thermal deformation suppression system of the present invention.

[0031] In the picture: 1. Spindle; 2. CNC machine tools; 3. Bearing temperature sensor; 4. Spindle temperature sensor; 5. Variable frequency oil cooling module; 6. Spiral cooling channel; 7. Bearing housing; 8. Multi-hole spray head. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this invention. Example 1:

[0033] like Figures 1-3 As shown, the present invention provides a method for suppressing thermal deformation. It should be noted that this embodiment takes the machining axis of the CNC machine tool 2 as an example to illustrate the specific characteristics of the component to be cooled. That is, the present invention provides a method for suppressing thermal deformation of the machining axis of the CNC machine tool 2. Of course, it can also be applied to other processing equipment, as long as thermal deformation can be generated during processing. This article only uses one embodiment as an example for illustration. Other embodiments are the same and will not be described in detail.

[0034] The following descriptions of the components to be cooled use the machining shaft as an example; different parts refer to the spindle 1 and bearing housing 7 of the machining shaft. Specifically, this method for suppressing thermal deformation includes the following steps: Step S1: The CNC machine tool 2 starts, and the machining axis receives the signal to cut the workpiece; the temperature sensor collects the temperature data of different parts of the machining axis in real time; specifically, the spindle temperature sensor 4 collects the temperature Ta of the spindle 1 of the machining axis, and the bearing temperature sensor 3 collects the bearing temperature Tb of the bearing housing 7. Step S2: Based on the acquired temperature data, dynamically adjust the cooling output capacity of the variable frequency oil cooling module 5; It should be noted that the variable frequency oil cooling module 5 includes a first cooling module for cooling the first position of the machining axis and a second cooling module for cooling the second position of the machining axis. In this embodiment, the first position is the main shaft 1, and the second position is the bearing seat 7; Specifically, this step includes: Step S21: Obtain the maximum temperature value inside the machining axis; that is, determine the magnitude of the spindle temperature Ta and the bearing temperature Tb, and obtain the maximum temperature value Tmax based on the maximum value of the two. Step S22: Determine the range of the maximum temperature value; In this embodiment, the temperature range is divided into three ranges: a low temperature range below 30°C, a medium temperature range between 30°C and 50°C, and a high temperature range above 50°C; For example, when Tmax < 30°C, it is determined to be in the low temperature range; when 30°C < Tmax < 50°C, it is determined to be in the medium temperature range; when Tmax > 50°C, it is determined to be in the high temperature range. Step S23: Adjust the opening of the regulating valve in the first cooling module based on different ranges; Specifically, in step S231, when the maximum temperature value is in the low temperature range, the regulating valve in the first cooling module is adjusted to operate at a small opening. Step S232: When the maximum temperature value is in the medium temperature range, adjust the regulating valve in the first cooling module to operate at a medium opening degree; Step S233: When the maximum temperature value is in the high temperature range, adjust the regulating valve in the first cooling module to open to the maximum degree of operation.

[0035] This invention achieves stepped, precise temperature control, low-temperature, low-consumption cooling, and high-temperature enhanced cooling, reducing energy waste while ensuring effective temperature control and adapting to different heat load conditions.

[0036] It should be noted that in this embodiment, "small opening" refers to adjusting the regulating valve (shut-off valve) opening to 50%, "medium opening" refers to adjusting the regulating valve opening to 75%, and "large opening" refers to adjusting the regulating valve opening to 100%. That is, when Tmax < 30℃, it is determined to be in the low-temperature range, and the opening of the regulating valve (shut-off valve) in the first cooling module is adjusted to 50% to maintain the basic system circulation, avoid overcooling, and ensure the stability of the oil circulation. When 30℃ < Tmax < 50℃, it is determined to be in the medium-temperature range, and the opening of the regulating valve (shut-off valve) in the first cooling module is adjusted to 75% to achieve a balance between energy efficiency and cooling capacity. When Tmax > 50℃, it is determined to be in the high-temperature range, and the opening of the regulating valve (shut-off valve) in the first cooling module is adjusted to 100% to output maximum cooling capacity and quickly suppress temperature rise. The system enters emergency cooling mode, continuously monitoring the temperature until it drops below 50℃, and then gradually reduces the frequency.

[0037] To achieve more precise control, in this embodiment, after adjusting the opening of the regulating valve in the first cooling module based on different ranges, the following steps are also included: Step S234: Obtain the real-time maximum temperature value inside the machining axis again; similarly, the spindle temperature Ta of the machining axis is collected by the spindle temperature sensor 4, and the bearing temperature Tb of the bearing housing 7 is collected by the bearing temperature sensor 3; determine the magnitude of the spindle temperature Ta and the bearing temperature Tb, and obtain the real-time maximum temperature value Tmax based on the maximum value of the two. Step S235: Determine whether the real-time maximum temperature value has reached the preset temperature value; In this embodiment, the preset temperature value is 40℃. Of course, other temperature values ​​can also be used, and the specific setting value depends on the actual situation of the equipment. This invention does not limit it; This step is to determine whether the real-time maximum temperature value Tmax has reached 40℃ after the previous opening adjustment. Step S236: When the determination is yes, gradually reduce the opening of the regulating valve in the first cooling module.

[0038] After the temperature reaches the target, the opening of the regulating valve is gradually reduced to avoid a sudden valve closure that could cause a temperature rebound. This achieves a smooth cooling transition, maintains stable component temperature, and prevents secondary thermal deformation caused by sudden temperature changes.

[0039] When the real-time maximum temperature value reaches 40℃, and the opening of the regulating valve is also reduced, it is necessary to determine the rate of temperature change to avoid large temperature fluctuations after the valve is reduced. In this embodiment, when the determination is correct, that is, when the real-time maximum temperature value Tmax = 40℃ or close to 40℃, after gradually reducing the opening of the regulating valve in the first cooling module, the following steps are also taken: Step S237: Obtain the real-time maximum temperature value inside the machining axis again; similarly, the spindle temperature Ta of the machining axis is collected by the spindle temperature sensor 4, and the bearing temperature Tb of the bearing housing 7 is collected by the bearing temperature sensor 3; determine the magnitude of the spindle temperature Ta and the bearing temperature Tb, and obtain the real-time maximum temperature value Tmax based on the maximum value of the two. Step S238: Compare the obtained real-time maximum temperature value with the preset reference temperature value to obtain the average temperature change rate within a set time. In this embodiment, the preset reference temperature value can be 40℃, which is equal to the previous preset temperature value. The set time can be 10s, that is, compare the obtained real-time maximum temperature value Tmax with the preset reference temperature value 40℃ to obtain the average temperature change rate within 10s. Step S239: Based on the obtained average temperature change rate ΔT, set the amplitude adjustment of the regulating valve in the first cooling module. In this embodiment, the amplitude adjustment is set to 2% of the opening.

[0040] Specifically, when the average rate of change ΔT > 0.2℃ / s, the opening of the regulating valve in the first cooling module is increased by 2%, and the current opening is maintained. When the average rate of change ΔT < 0.2℃ / s, the opening of the regulating valve in the first cooling module is reduced by 2%, and the current opening is maintained.

[0041] This invention calculates the average rate of temperature change to set the opening of the amplitude adjustment valve, upgrading from step adjustment to closed-loop fine adjustment. It dynamically corrects the cooling intensity according to the rate of temperature change, achieving precise and stable temperature control, reducing the temperature fluctuation range, and further suppressing thermal deformation.

[0042] In this embodiment, after step S21, obtaining the maximum temperature value inside the machining axis, the method further includes: Step S211: Obtain the first circuit oil pressure in the first cooling module; In this embodiment, the first return oil pressure refers to the oil pressure in the spiral cooling channel of the spindle 1 or the oil pressure of the pipeline connected to the spiral cooling channel of the spindle 1. Step S212: When the first return oil pressure is lower than the first preset threshold, increase the output speed of the variable frequency oil pump in the first cooling module. In this embodiment, the first preset threshold can be 1.0 MPa, but other pressure values ​​can also be selected according to actual conditions. That is, when the oil pressure in the spiral cooling channel of the spindle 1 is lower than 1.0 MPa, the variable frequency oil pump in the first cooling module is controlled to increase its frequency, thereby increasing the output speed.

[0043] This invention monitors the oil pressure in the first circuit, alarms when the oil pressure is too low and increases the oil pump speed, monitors the operating status of the cooling circuit in real time, promptly detects faults such as oil circuit blockage and leakage, avoids cooling failure due to insufficient oil pressure, and automatically adjusts the speed to ensure cooling continuity, improves system stability and safety, and complements the valve opening adjustment of the first cooling module to improve the overall cooling system control flexibility.

[0044] The above is the control flow for the spindle 1 cooling circuit; the following is the control flow for the bearing cooling circuit. Specifically: Step S24: Based on the acquired maximum temperature value, control the variable frequency oil pump of the second cooling module to operate at a preset corresponding output speed. Specifically, according to the acquired maximum temperature value Tmax, retrieve the preset output frequency f of the corresponding variable frequency oil pump in the system to control the variable frequency oil pump to start operation at the corresponding output speed.

[0045] Through the above controls, independent cooling is achieved in different zones, allowing for precise regulation based on the varying heat loads of different parts of the component. This avoids localized insufficient or excessive cooling caused by uniform cooling across the entire area, improving temperature control uniformity. Using the highest temperature as the core control basis, it identifies key overheating points of the component and adjusts in stages according to temperature ranges. The logic is simple and the response is highly efficient, quickly matching the corresponding cooling intensity and avoiding adjustment lag.

[0046] As an optional embodiment of the present invention, after step S24, controlling the second cooling module to operate at a preset corresponding output frequency based on the maximum temperature value, the method further includes: Step S241: Obtain the second circuit oil pressure in the second cooling module; specifically, obtain the bearing cooling circuit oil pressure P in the multi-hole spray on the 7th side of the bearing housing. Step S242: When the second return oil pressure is lower than the second preset threshold, an alarm is triggered and the output speed of the variable frequency oil pump of the second cooling module is increased.

[0047] This invention controls the speed of the variable frequency oil pump of the second cooling module according to the maximum temperature value. The second cooling module adopts direct speed control, which results in faster response and more linear cooling output.

[0048] Step S3: The thermal compensation module acquires the thermal elongation of the machining axis in real time; specifically, it uses a laser interferometer to acquire the thermal elongation ΔLa of the main spindle 1 of the machining axis; when the thermal elongation ΔLa > 0 is detected for the first time, the next step S4 is performed.

[0049] Step S4: Based on the acquired thermal expansion, adjust the cooling output capacity of the variable frequency oil cooling module 5. At the same time, based on the thermal expansion, calculate the compensation value and write it into the servo command to dynamically compensate the machining coordinates of the machining axis.

[0050] Specifically, in step S41, based on the thermal elongation ΔLa, the heat load is determined, and the output frequency of the variable frequency oil pump in the variable frequency oil cooling module 5 is actively increased to improve the pump speed. Step S42: Calculate the compensation value based on the thermal elongation △La, and write the servo instruction insertion position instruction. Adjust the machining coordinates of the spindle 1 tool head through the servo motor to perform the operation.

[0051] This invention collects temperature data from different parts of the machining axis in real time, achieving full-area temperature sensing of the component. This avoids the limitations of single-point temperature measurement, accurately grasps the heat distribution state, and provides a real and reliable data foundation for subsequent cooling adjustment, reducing cooling control deviations caused by inaccurate temperature measurement from the source. Through temperature data, the cooling output capacity of the variable frequency oil cooling module 5 is dynamically adjusted, abandoning the traditional constant cooling mode and achieving real-time adaptive adjustment of cooling intensity with temperature. This avoids energy waste due to overcooling and thermal deformation caused by overheating, balancing cooling efficiency and temperature control accuracy, and reducing energy consumption. The thermal compensation module obtains the thermal elongation of the machining axis in real time, directly monitoring the core indicators of thermal deformation. This overcomes the error of indirectly estimating deformation based solely on temperature, obtaining the true deformation amount, providing accurate basis for coordinate compensation and cooling control, improving the reliability of deformation control, and forming a dual suppression mechanism of cooling temperature control + coordinate compensation. This reduces thermal deformation from the source and corrects the machining coordinates in real time for existing deformation, doubly ensuring machining accuracy and significantly reducing the impact of thermal deformation on machining accuracy. Example 2:

[0052] like Figures 4-8As shown, the present invention provides a thermal deformation suppression system for performing the thermal compensation method in Embodiment 1. Specifically, the thermal deformation suppression system includes: The variable frequency oil cooling module 5 can dynamically adjust the cooling output capacity based on the real-time temperature data acquired within the machining axis. The thermal compensation module is network-connected to the variable frequency oil cooling module 5 to dynamically correct the machining coordinates based on the real-time temperature data obtained by the variable frequency oil cooling module 5, and to dynamically adjust the cooling output capacity of the variable frequency oil cooling module 5 based on the obtained thermal elongation of the machining axis.

[0053] The thermal deformation suppression system of this invention includes a variable frequency oil cooling module 5 + a thermal compensation module, which are connected in a network for coordinated control. This enables data exchange and linkage control between temperature control and deformation compensation, breaking the limitations of a single module working independently and forming an integrated thermal deformation suppression system. The control accuracy and response speed are significantly improved.

[0054] This invention addresses the shortcomings of traditional cooling systems, which cannot dynamically respond to temperature gradient changes, resulting in low temperature control accuracy (±1.5℃) and inability to match fluctuating heat loads. It also resolves the issue of unbalanced heat distribution between the spindle and bearings caused by a single cooling path, leading to local hotspot temperatures exceeding limits by more than 5℃ and accelerating component aging. Furthermore, it addresses the problem of thermal compensation relying on static models, which cannot correct thermal elongation in real time, causing compensation lag (>200ms) and error accumulation. Finally, it addresses the issue of independent operation of cooling and compensation technologies, lacking a data collaboration mechanism, which weakens the effect of suppressing thermal deformation.

[0055] Specifically, the variable frequency oil cooling module 5 is a dual-circulation cooling module, including a first cooling module and a second cooling module independently set at different positions on the machining axis. The different positions here refer to the spindle 1 and the bearing housing 7. That is, the first cooling module is connected to the spindle 1 to cool the spindle 1 and suppress thermal deformation of the spindle 1, and the second cooling module is connected to the bearing housing 7 to cool the bearing housing 7.

[0056] This invention features dual-loop independent operation without interference, allowing for individual adjustment based on the heat dissipation needs of different areas of the component, resulting in more comprehensive cooling coverage. Furthermore, a failure in one loop does not affect the other loop, enhancing system redundancy.

[0057] In this embodiment, the first cooling module includes a first variable frequency oil cooling pump, a first temperature sensor, a first pressure sensor, a first cooling circuit, and a regulating valve. The first cooling circuit includes a spiral cooling channel 6 (flow rate 10 L / min) embedded in the spindle 1 and a pipeline connecting the first variable frequency oil cooling pump and the spiral cooling channel 6. The regulating valve is located between the first variable frequency oil cooling pump and the first cooling circuit. The first temperature sensor is also the spindle temperature sensor 4; the spindle temperature sensor 4 is located in the cutting area of ​​the spindle 1; the first pressure sensor is also the spindle 1 pressure sensor, located in the spiral cooling channel 6 or the pipeline. The spiral cooling channel 6 is provided in the spindle 1 body, integrally formed by CNC milling, and the inner wall of the channel is nickel-plated to enhance corrosion resistance. The present invention features a spiral embedded channel that increases the cooling contact area, resulting in uniform and efficient cooling; a regulating valve precisely controls the flow rate, and multiple sensors enable full monitoring of temperature and pressure, achieving closed-loop and precise cooling control.

[0058] As a further improvement of the present invention, the second cooling module includes a second variable frequency oil cooling pump, a second temperature sensor, a second cooling circuit, and a second pressure sensor; the second cooling circuit includes a plurality of spray elements spaced apart along the circumference of the bearing housing 7. Specifically, the spray elements are multi-hole spray heads 8 (flow rate 5L / min). The second temperature sensor is the bearing temperature sensor 3. The spray angle range of each multi-hole spray head 8 is 120°, and six multi-hole spray heads 8 are arranged along the circumference to achieve full coverage of the bearing housing 7, and to ensure that even if some of the multi-hole spray heads 8 fail, the multi-hole spray heads 8 on the left and right sides can still cover the damaged area. In this embodiment, the multi-hole spray heads 8 are arranged at an angle of 30° with the vertical direction, and the spray direction is tilted at 30° towards the bearing raceway area, ensuring that the oil mist accurately covers the bearing outer raceway and cage, solving the problem of local overheating.

[0059] In this invention, the first temperature sensor and the second temperature sensor are connected to the analog input port of the PLC via shielded twisted pair cables, with a sampling period of 1 second; the PLC has a built-in multi-level frequency conversion control program.

[0060] It should be noted that the first cooling module also includes an oil-cooled radiator. The first variable frequency oil-cooled pump is connected to the cooling medium oil in the oil-cooled radiator. The oil-cooled radiator uses a plate heat exchanger, and the cooling medium is ambient air. The regulating valve can be an electric ball valve, and its opening is controlled by the PLC through analog signals. In use, the cooling oil is output from the first variable frequency oil-cooled pump, flows through the spiral cooling channel 6, absorbs heat from the cutting area of ​​the spindle 1, enters the spindle 1 oil-cooled radiator for heat dissipation, and then circulates back to the first variable frequency oil-cooled pump. The first variable frequency oil-cooled pump is a variable frequency pump, and its speed is controlled by the PLC through analog output signals. Under normal operating conditions, the PLC sets its output frequency, corresponding to the rated flow rate.

[0061] It should be noted that the second cooling module also includes an oil-water heat exchanger, which is a shell-and-tube heat exchanger with cooling oil on the tube side and cooling water on the shell side. The second cooling module also includes a bearing oil circuit solenoid valve: a two-position three-way solenoid valve, controlled by a PLC via a 24V DC digital signal. The bearing cooling pipeline consists of multi-hole spray heads distributed in multiple directions on the bearing housing 7, forming an all-around oil mist spray system. Cooling oil is output from the second variable frequency oil cooling pump, and after being regulated by the solenoid valve, it is sprayed onto the bearing raceway and cage through the multi-hole spray heads, achieving both lubrication and cooling of the bearing.

[0062] The second variable frequency oil cooling pump is a variable frequency pump, and its speed is controlled by a PLC through digital output signals. Under normal operating conditions, the PLC sets its output frequency to correspond to the rated flow rate. The cooling water inlet of the oil-water heat exchanger is connected to an external cooling water system.

[0063] The spray-type cooling system of this invention covers the outer periphery of the component, providing fast and wide-ranging cooling. It works in conjunction with the embedded cooling in the first cooling module to form a synergistic cooling effect, further improving the overall cooling efficiency and uniformity.

[0064] As a further improvement of the present invention, the thermal compensation module includes a laser interferometer and a CNC compensation system; the laser interferometer and the CNC compensation system are signal-connected. The laser interferometer is mounted at a fixed reference point at the tail of spindle 1. The transmitting end of the interferometer is fixed to the machine tool, and the receiving end is fixed to the tail of spindle 1. Its measuring optical path is strictly parallel to the axis of spindle 1. The signal output end of the interferometer is directly connected to the CNC system via a high-speed interface to monitor the thermal elongation (ΔL) of spindle 1 in real time.

[0065] Compensation algorithm and execution: ① Data acquisition: The CNC system reads the real-time data of the laser interferometer once per second to obtain the thermal elongation (ΔL) of spindle 1.

[0066] ② Compensation Calculation: The linear expansion coefficient of the spindle 1 material is pre-stored within the CNC system. When the thermal expansion of spindle 1 is detected, the compensation value is calculated.

[0067] ③ Dynamic compensation: The CNC system writes the calculated compensation value into the position command in real time, and drives the servo motor through the servo driver to move the machining coordinate in the corresponding direction, thereby offsetting thermal expansion.

[0068] ④ Coordinated Adjustment: The CNC system and PLC exchange data in real time via industrial Ethernet. When the PLC detects that the cooling system has successfully reduced the temperature of spindle 1, resulting in a decrease in thermal expansion, the CNC system will automatically reduce or cancel the compensation value to avoid overcompensation.

[0069] System integration and collaborative control logic The core of this invention lies in the synergy of a dual mechanism of "active cooling + dynamic compensation". Its specific integration method is as follows: Data sharing: The PLC and CNC system establish a high-speed communication link via industrial Ethernet. The PLC sends the real-time temperature of spindle 1 and the operating status of the cooling system to the CNC system.

[0070] Collaborative control process: ① The laser interferometer detects thermal elongation, and the CNC system initiates compensation.

[0071] ② At the same time, the CNC system sends the thermal elongation value to the PLC.

[0072] ③ The PLC determines the heat load based on the thermal expansion value and actively increases the output frequency of the variable frequency oil cooler to increase the cooling capacity.

[0073] ④ As the cooling capacity increases, the temperature of spindle 1 decreases, and the thermal elongation decreases.

[0074] ⑤ The CNC system detects a decrease in thermal elongation and automatically reduces the compensation value to achieve dynamic adjustment of the compensation.

[0075] ⑥ This process forms a closed loop of "monitoring-compensation-cooling-remonitoring", which suppresses the heat source at the source and corrects the deformation in real time.

[0076] Practical application verification: Test scenario: Install this system on horizontal CNC machine tool 2 to process precision parts with a diameter of 50mm, with ambient temperature fluctuation of ±5℃.

[0077] Performance metrics: Temperature control accuracy: During continuous machining, the temperature of the cutting zone of spindle 1 remains stable within ±0.1℃ of the set value.

[0078] Heat deformation compensation accuracy: The compensation error for thermal elongation is less than ±1μm (±5μm for traditional systems).

[0079] Processing consistency: When processing multiple parts continuously, the dimensional tolerance of the parts is improved from ±20μm to ±5μm.

[0080] Economic benefits: Equipment maintenance cycle is extended by 30%, and the yield rate of processed products is increased to 99.5%.

[0081] Through the above embodiments, the present invention achieves active suppression and dynamic compensation of thermal deformation of spindle 1, significantly improving the stability and reliability of high-precision machining equipment.

[0082] This invention provides a laser interferometer for high-precision measurement of thermal elongation with minimal measurement error; the CNC compensation system directly incorporates servo commands, ensuring real-time and accurate compensation response, perfectly suited for high-precision machining scenarios.

[0083] Furthermore, in this embodiment, the variable frequency oil cooling module 5 in the thermal deformation suppression system adopts a programmable logic controller (PLC) control system with four analog input modules, while the thermal compensation module adopts a CNC control system. The millisecond-level data exchange between the PLC and CNC is achieved via the EtherCAT industrial Ethernet protocol. This invention uses a laser interferometer to monitor the thermal elongation of the spindle 1 in real time, and combines this with the EtherCAT industrial Ethernet between the PLC and CNC to achieve millisecond-level data interaction (control cycle of 1 second, adjustment step ±2Hz), forming a closed loop of "monitoring-compensation-cooling-re-monitoring." This shortens the compensation response time to the millisecond level, truly achieving dynamic adjustment based on real-time sensor data, and suppressing thermal deformation from the source.

[0084] This invention achieves proactive suppression of spindle 1 thermal deformation by integrating a variable frequency oil cooling system, a dual-circulation cooling structure, and a dynamic thermal compensation mechanism. Specifically, the first cooling circuit, i.e., the spindle 1 cooling circuit, employs an embedded spiral cooling channel 6 (flow rate 10L / min), and the second cooling circuit, i.e., the bearing cooling circuit, employs a multi-hole spray head structure 8 (flow rate 5L / min). Both circuits are driven by independent variable frequency oil pumps. A laser interferometer monitors the thermal elongation of spindle 1 in real time. The CNC system calculates the compensation value every second and writes it into servo commands. When the PLC detects a temperature drop, it automatically reduces the compensation value. The PLC and CNC achieve millisecond-level data interaction via EtherCAT industrial Ethernet, forming a closed-loop control process of "monitoring-compensation-cooling-re-monitoring," suppressing thermal deformation at its source and correcting errors in real time. This invention achieves a spindle 1 temperature control accuracy of ±0.1℃ and a thermal deformation compensation accuracy of ±1μm. All components are connected via industrial Ethernet, enabling data sharing. Equipment maintenance cycles are extended by 30%, and the processing yield is increased to 99.5%.

[0085] First, it should be noted that "inward" refers to the direction towards the center of the storage space, while "outward" refers to the direction away from the center of the storage space.

[0086] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the appendix. Figure 1 The orientations or positional relationships shown are for the purpose of facilitating and simplifying the description of the present invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

[0087] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0088] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0089] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0090] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0091] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for suppressing thermal deformation, characterized in that, Includes the following steps: Real-time acquisition of temperature data from different parts of the component to be cooled; Based on the acquired temperature data, the cooling output capacity of the variable frequency oil cooling module is dynamically adjusted; The thermal compensation module acquires the thermal elongation of the component to be cooled in real time. Based on the acquired thermal expansion, the cooling output capacity of the variable frequency oil cooling module is adjusted. At the same time, based on the thermal expansion, the compensation value is calculated and written into the servo command to dynamically compensate the machining coordinates of the component to be cooled.

2. The method according to claim 1, characterized in that, The variable frequency oil cooling module includes a first cooling module for cooling a first location of the component to be cooled and a second cooling module for cooling a second location of the component to be cooled; the dynamic adjustment of the cooling output capability of the variable frequency oil cooling module based on the acquired temperature data includes: Obtain the maximum temperature value inside the component to be cooled; Determine the range containing the maximum temperature value; Adjust the opening degree of the regulating valve in the first cooling module based on different ranges; Based on the obtained maximum temperature value, the variable frequency oil pump of the second cooling module is controlled to run at the preset corresponding output speed.

3. The method according to claim 2, characterized in that, The adjustment of the opening degree of the regulating valve in the first cooling module based on different intervals includes: When the maximum temperature value is in the low temperature range, adjust the regulating valve in the first cooling module to operate at a small opening. When the maximum temperature value is in the medium temperature range, adjust the regulating valve in the first cooling module to open to the medium degree of operation. When the maximum temperature value is in the high temperature range, adjust the regulating valve in the first cooling module to open to the maximum degree of operation.

4. The method according to claim 2, characterized in that, After adjusting the opening of the regulating valve in the first cooling module based on different intervals, the method further includes: Obtain the real-time maximum temperature value inside the component to be cooled again; Determine whether the real-time maximum temperature value has reached the preset temperature value; When the determination is yes, the opening of the regulating valve in the first cooling module is gradually reduced.

5. The method according to claim 4, characterized in that, When the determination is yes, after gradually reducing the opening of the regulating valve in the first cooling module, the process further includes: Obtain the real-time maximum temperature value inside the component to be cooled again; The real-time maximum temperature value is compared with the preset reference temperature value to obtain the average rate of temperature change over a set time period. Based on the obtained average temperature change rate, the opening degree of the regulating valve in the first cooling module is set to adjust the amplitude.

6. The method according to claim 2, characterized in that, After controlling the second cooling module to operate at a preset corresponding output frequency based on the maximum temperature value, the method further includes: Obtain the second circuit oil pressure within the second cooling module; When the second return oil pressure is lower than the second preset threshold, an alarm is triggered and the output speed of the variable frequency oil pump of the second cooling module is increased.

7. The method according to claim 2, characterized in that, After obtaining the maximum temperature value inside the component to be cooled, the process further includes: Obtain the first circuit oil pressure within the first cooling module; When the first return oil pressure is lower than the first preset threshold, the output speed of the variable frequency oil pump of the first cooling module is increased.

8. A heat distortion suppression system, characterized in that, For performing the method as described in any one of claims 1-7, the thermal deformation suppression system comprises: The variable frequency oil cooling module can dynamically adjust the cooling output capacity based on the real-time temperature data of the component to be cooled. A thermal compensation module is network-connected to the variable frequency oil cooling module to dynamically correct the processing coordinates based on the real-time temperature data obtained by the variable frequency oil cooling module, and to dynamically adjust the cooling output capacity of the variable frequency oil cooling module based on the thermal elongation of the component to be cooled.

9. The heat distortion suppression system according to claim 8, characterized in that, The variable frequency oil cooling module is a dual-cycle cooling module, including a first cooling module and a second cooling module independently set at different positions of the component to be cooled.

10. The heat distortion suppression system according to claim 9, characterized in that, The first cooling module includes a first variable frequency oil cooling pump, a first temperature sensor, a first pressure sensor, a first cooling circuit, and a regulating valve. The first cooling circuit includes a spiral cooling channel embedded in the component to be cooled. The regulating valve is disposed between the first variable frequency oil cooling pump and the first cooling circuit.

11. The heat distortion suppression system according to claim 9, characterized in that, The second cooling module includes a second variable frequency oil cooling pump, a second temperature sensor, a second cooling circuit, and a second pressure sensor; the second cooling circuit includes a plurality of spray elements spaced apart along the circumferential direction of the component to be cooled.

12. The heat distortion suppression system according to claim 8, characterized in that, The thermal compensation module includes a laser interferometer and a numerical control compensation system; the laser interferometer and the numerical control compensation system are connected by signals.

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