Intelligent vibration measuring milling cutter with symmetrically arranged sensors

Abstract

The application discloses a sensor symmetric arrangement type intelligent vibration measuring milling cutter, which comprises a blade (1), a milling cutter disc (3), a cutter bar (5), a clamping component (8), a containing space and a signal processing unit; the application can measure the cutter vibration in milling processing in real time, and can wirelessly transmit the cutter vibration to an upper computer, so that the cutter state monitoring, cutter wear prediction and chatter monitoring and other functions can be realized.

Description

Technical Field

[0001] This invention relates to the field of intelligent vibration measurement technology in machining, specifically to an intelligent vibration measurement milling cutter with symmetrically arranged sensors. Background Technology

[0002] Milling cutters are among the most widely used cutting tools in the manufacturing industry. Many key basic components that require high precision and high surface quality are machined by milling. Therefore, improving their level of intelligence can significantly improve the overall level of industry.

[0003] In milling, improper settings of machining parameters such as cutting speed and feed rate can reduce machining efficiency or cause chatter, affecting machining quality and, in severe cases, even leading to chipping or tool breakage. Furthermore, due to the high-speed, high-frequency material removal by the cutting tool, varying degrees of wear will occur after a certain machining time. When the wear exceeds a certain value, machining accuracy will be reduced.

[0004] Intelligentizing cutting tools typically requires modifying the shape and internal structure of the inserts or tool holders. This necessitates combining technologies such as sensors, signal processing, and computers to monitor the cutting process in real time and analyze the cutting status. Vibration accompanies the entire machining process and is considered one of the most telling variables reflecting the machining state. Therefore, monitoring cutting vibration to detect abnormalities can provide insights for optimizing cutting parameters, timely tool replacement, and even prevent catastrophic failures, providing an information foundation for high-quality and safe machining.

[0005] However, most current research on vibration-measuring end mills focuses on fixing the vibration sensor to the central axis of the tool holder to ensure that the sensor's axis coincides with the tool holder's axis. This design approach usually requires machining a through hole in the tool holder to install the sensor, but this solution significantly weakens the overall rigidity of the tool; alternatively, it can directly utilize the existing central through hole in the tool holder for installation, but this solution is not conducive to installation on long end mills and affects the tool's internal cooling function, thus limiting its application scenarios. Therefore, a vibration-measuring end mill with two vibration sensors symmetrically arranged is designed, which can eliminate the influence of centrifugal acceleration and tangential acceleration when the sensor is offset through simple calculations.

[0006] Therefore, developing a smart vibration measuring milling cutter with symmetrically arranged sensors is of great significance. Summary of the Invention

[0007] The purpose of this invention is to provide a smart vibration measuring milling cutter with symmetrical sensor arrangement, including inserts, milling cutter head, cutter bar, clamping components, accommodating space and signal processing unit.

[0008] The milling cutter head is axially fixed to the head end of the cutter holder.

[0009] The milling cutter head has multiple blades evenly distributed circumferentially.

[0010] The tool holder has a step machined at its head end, and symmetrical vibration sensor mounting slots are opened around the step.

[0011] The lower end face of the vibration sensor mounting slot is provided with a signal hole along the axial direction of the tool holder, which leads to the tail end of the tool holder.

[0012] A radial hole is opened at the tail end of the tool holder, corresponding to the position of the signal hole.

[0013] The signal hole and radial hole connect the vibration sensor mounting slot to the outside.

[0014] The tail end of the tool holder is provided with a housing.

[0015] The outer shell is fixed to the tail end of the tool holder by outer shell fixing screws and encloses the accommodating space.

[0016] In the accommodating space, the heat-fitted base is connected to the tool holder by heat fitting.

[0017] The heat-fitting base is used to fix the battery bracket and the circuit board base.

[0018] The battery holder is circumferentially distributed with an array of arc-shaped lithium batteries.

[0019] The circuit board base is used to fix the signal processing circuit board.

[0020] The signal processing circuit board is arranged in the accommodating space.

[0021] The signal processing unit includes vibration sensors symmetrically arranged at the head end of the tool holder.

[0022] The vibration sensor is fixed in the vibration sensor mounting slot.

[0023] The vibration sensor is connected to the signal processing circuit board via terminal leads.

[0024] The terminals are placed inside the signal hole and the radial hole.

[0025] Furthermore, during machining, the cutting tool experiences high-frequency collisions and compression as it cuts the workpiece, leading to tool vibration. The vibration sensor collects the vibration signals during the cutting process. The terminal wire transmits the signal from the vibration sensor to the signal processing circuit board at the tail end.

[0026] The signal processing circuit board amplifies and converts the signal from analog to digital, then wirelessly transmits it to the host computer via TCP / IP protocol. The host computer analyzes the cutting conditions to obtain tool condition monitoring, prediction of tool wear, and results of remaining tool life.

[0027] Furthermore, the steps by which the host computer analyzes the cutting conditions to obtain tool condition monitoring, prediction of tool wear, and remaining tool life results are as follows:

[0028] 1) Under the maximum cutting parameters within the tool's tolerance range, cut from three directions of the square workpiece, record the collected cutting signals, and select the sum of the largest vibration values ​​in the three directions as the threshold for determining whether a tool breakage has occurred.

[0029] 2) Collect different tool wear values ​​and cutting vibration signals when chatter occurs to obtain the original dataset.

[0030] 3) Perform feature extraction on the signal data collected in step 2), such as time domain analysis, frequency domain analysis, and time-frequency domain analysis, to obtain the model construction dataset.

[0031] 4) Construct an initial real-time monitoring model for tool wear and a chatter prediction model.

[0032] 5) Based on the model construction dataset, the initial real-time tool wear monitoring model and chatter prediction model are trained to obtain the trained real-time tool wear monitoring model and chatter prediction model.

[0033] 6) Real-time acquisition of tool vibration signals during tool cutting, inputting the processed signal feature set into the real-time tool wear monitoring model and chatter prediction model, performing decision analysis on the cutting conditions of the tool under test, and obtaining tool condition monitoring, prediction of tool wear and remaining life results.

[0034] Furthermore, the tool holder has a cylindrical strip structure and a central through hole at its center.

[0035] The milling cutter disc is axially fixed to the head end of the cutter shank by milling cutter disc axial fixing screws, and is radially fixed by two flat key screws screwed into a flat key.

[0036] Furthermore, the milling cutter disc has multiple blades evenly distributed circumferentially via blade screws.

[0037] Furthermore, the vibration sensor mounting slot is sealed by a sleeve.

[0038] The inner wall of the sleeve has grooves on the top and bottom for installing rubber sealing rings.

[0039] The sleeve has a side through hole, and the tool holder has a corresponding threaded hole at the corresponding height.

[0040] The sleeve is fixed to the tool holder by screws.

[0041] Furthermore, a groove is provided on the inner side of the upper end of the outer casing for installing a rubber sealing ring. A groove is provided at the tail end of the blade holder for installing a rubber sealing ring.

[0042] The circuit board base is provided with threaded holes corresponding to the holes on the circuit board.

[0043] The signal processing circuit board is fixed to the circuit board base by hexagonal copper pillars.

[0044] Furthermore, the signal processing circuit board integrates a control module, a signal preprocessing module, an analog-to-digital conversion module, a wireless transmission module, and a power supply module.

[0045] The power module is connected to the arc-shaped lithium battery.

[0046] The voltage signal corresponding to the three-dimensional vibration sensor is amplified by the signal preprocessing module and then enters the analog-to-digital conversion module for encoding.

[0047] The encoded digital signal is transmitted to the wireless transmission module via SPI. The wireless transmission module then transmits the encoded digital signal to the host computer.

[0048] Furthermore, the outer casing is fixed to the tool holder by outer casing fixing screws.

[0049] The outer wall of the housing has a through hole I to fix the membrane switch. The membrane switch is connected to the power module and controls the on / off of the lithium battery power supply.

[0050] Furthermore, the arc-shaped lithium battery is a rechargeable lithium battery, which is attached and fixed to the battery bracket.

[0051] The outer wall of the housing has a through hole II to fix the magnetic charging interface. The charging interface is connected to the power module.

[0052] The technical advantages of this invention are undeniable. This invention involves simple machining of existing long-handled end mills, minimizing the weakening of the overall tool rigidity due to structural modifications, and without affecting the tool's internal cooling function. By embedding sensors and signal processing circuitry through grooves, through-holes, and other structures, the overall size of the tool is essentially not increased.

[0053] Meanwhile, the present invention utilizes two three-dimensional vibration sensors arranged symmetrically at 180° circumference to measure the vibration value of the tool in real time through a certain calculation method.

[0054] In addition, the present invention features a modular design for the signal processing circuit, integrating amplification, AD conversion, and wireless transmission onto a single circuit board to reduce the overall size of the data acquisition section and enable real-time wireless transmission of vibration signals to the host computer.

[0055] This invention can transmit three-dimensional vibration information of the cutting tool during the cutting process to the host computer in real time. After processing and analysis, it can promptly determine whether the current state of the tool is abnormal, such as chipping, tool breakage, and tool wear. This provides a reference for optimizing cutting parameters, timely tool replacement, and even avoids catastrophic failures, laying an information foundation for high-quality and high-safety machining. Attached Figure Description

[0056] Figure 1 This is a schematic diagram of the overall appearance of the milling cutter;

[0057] Figure 2 This is a cross-sectional view of the tool tip;

[0058] Figure 3 This is a cross-sectional view of the tool tail end;

[0059] Figure 4 This is a schematic diagram of the vibration sensor installation.

[0060] Figure 5 This is a cross-sectional view of the sleeve installation.

[0061] Figure 6 A cross-sectional view of the signal processing circuit board being installed;

[0062] Figure 7 This is a schematic diagram of each module on the signal processing circuit board;

[0063] Figure 8 This is a strain contour plot generated by ANSYS simulation.

[0064] Figure 9 This is a schematic diagram illustrating the principle of tool vibration measurement.

[0065] Figure 10 This is a schematic diagram of a signal acquisition system.

[0066] In the diagram: 1. Blade; 2. Blade screw; 3. Milling cutter head; 4. Sleeve; 5. Tool holder; 6. Magnetic charging interface; 7. Membrane switch; 8. Clamping component; 9. Housing fixing screw; 10. Housing; 11. Sleeve side through hole; 12. Milling cutter head axial fixing screw; 13. Flat key; 14. Flat key screw; 15. Sleeve rubber sealing ring; 16. Axial signal hole; 17. Vibration sensor; 18. Machining through hole; 19. Through hole screw; 20. Tool holder center through hole; 21. Housing rubber sealing ring; 22. Signal processing circuit board. 23 Circuit board base and battery compartment fixing screws, 24 Circuit board base, 25 Arc-shaped lithium battery, 26 Battery bracket, 27 Rubber sealing ring at the tail end of the tool bar, 28 Heat-fit base, 29 Radial hole, 30 Circuit board fixing screws, 31 Hexagonal copper pillars, 32 Sleeve fixing screws, 33 Vibration sensor fixing screws, 34 Vibration sensor mounting slot, 35 Terminal block, 36 Analog-to-digital conversion module, 37 Signal preprocessing module, 38 Power supply module, 39 Wireless transmission module, 40 Control module. Detailed Implementation

[0067] The present invention will be further described below with reference to embodiments, but it should not be construed that the scope of the present invention is limited to the following embodiments. Various substitutions and modifications made based on ordinary technical knowledge and common practices in the art without departing from the above-described technical concept of the present invention should be included within the scope of protection of the present invention.

[0068] Example 1:

[0069] See Figures 1 to 10 A smart vibration measuring milling cutter with symmetrically arranged sensors includes a cutting tool 1, a milling cutter head 3, a cutter bar 5, a clamping component 8, a accommodating space, and a signal processing unit.

[0070] The milling cutter disc 3 is axially fixed to the head end of the cutter shank 5.

[0071] The milling cutter head 3 has multiple blades 1 evenly distributed circumferentially.

[0072] The tool holder 5 has a step machined at its head end, and a symmetrical vibration sensor mounting groove 34 is opened on the circumference of the step.

[0073] The lower end face of the vibration sensor mounting groove 34 is provided with a signal hole 16 along the axial direction of the tool bar, and the signal hole 16 leads to the tail end of the tool bar.

[0074] A radial hole 29 is opened at the tail end of the tool bar 5 at the position corresponding to the signal hole 16.

[0075] The signal hole 16 and the radial hole 29 connect the vibration sensor mounting slot 34 to the outside.

[0076] The tail end of the cutter bar 5 is provided with a housing 10.

[0077] The outer shell 10 is fixed to the tail end of the tool bar 5 by the outer shell fixing screws 9 and encloses the accommodating space.

[0078] In the accommodating space, the heat-fitted base 28 is connected to the tool holder 5 by heat fitting.

[0079] The heat-fitting base 28 is used to fix the battery bracket 26 and the circuit board base 24.

[0080] The battery holder 26 is circumferentially distributed with an array of arc-shaped lithium batteries 25.

[0081] The circuit board base 24 is used to fix the signal processing circuit board 22.

[0082] The signal processing circuit board 22 is arranged in the accommodating space.

[0083] The signal processing unit includes vibration sensors 17 symmetrically arranged at the head end of the tool holder 5.

[0084] The vibration sensor 17 is fixed in the vibration sensor mounting slot 34.

[0085] The vibration sensor 17 is connected to the signal processing circuit board 22 via a terminal lead from the terminal 35.

[0086] The terminal block 35 is placed inside the signal hole 16 and the radial hole 29.

[0087] During machining, the cutting tool 1 experiences high-frequency collisions and compression while cutting the workpiece, leading to tool vibration. The vibration sensor 17 collects the vibration signals during the cutting process. The terminal wire transmits the signal from the vibration sensor 17 to the signal processing circuit board 22 at the tail end.

[0088] The signal processing circuit board 22 amplifies and converts the signal from analog to digital, then wirelessly transmits it to the host computer via TCP / IP protocol. The host computer analyzes the cutting conditions to obtain tool condition monitoring, prediction of tool wear, and results of remaining tool life.

[0089] The steps by which the host computer analyzes the cutting conditions and obtains tool condition monitoring, tool wear prediction, and remaining life results are as follows:

[0090] 1) Under the maximum cutting parameters within the tool's tolerance range, cut from three directions of the square workpiece, record the collected cutting signals, and select the sum of the largest vibration values ​​in the three directions as the threshold for determining whether a tool breakage has occurred.

[0091] 2) Collect different tool wear values ​​and cutting vibration signals when chatter occurs to obtain the original dataset.

[0092] 3. Perform feature extraction on the signal data collected in step 2), such as time domain analysis, frequency domain analysis, and time-frequency domain analysis, to obtain the model construction dataset.

[0093] 4) Construct an initial real-time monitoring model for tool wear and a chatter prediction model.

[0094] 5) Based on the model construction dataset, the initial real-time tool wear monitoring model and chatter prediction model are trained to obtain the trained real-time tool wear monitoring model and chatter prediction model.

[0095] 6) Real-time acquisition of tool vibration signals during tool cutting, inputting the processed signal feature set into the real-time tool wear monitoring model and chatter prediction model, performing decision analysis on the cutting conditions of the tool under test, and obtaining tool condition monitoring, prediction of tool wear and remaining life results.

[0096] The tool holder 5 is a cylindrical strip structure, and a central through hole 20 is provided at the center.

[0097] The milling cutter disc 3 is axially fixed to the head end of the cutter bar 5 by the milling cutter disc axial fixing screw 12, and is radially fixed by two flat key screws 14 screwed into the flat key 13.

[0098] Multiple blades 1 are evenly distributed circumferentially on the milling cutter disc 3 via blade screws 2.

[0099] The vibration sensor mounting slot 34 is sealed by the sleeve 4.

[0100] The inner wall of the sleeve 4 has grooves on the upper and lower surfaces for installing the sleeve rubber sealing ring 15.

[0101] The sleeve 4 has a sleeve side through hole 11, and the tool holder 5 has a corresponding threaded hole at the corresponding height at the head end.

[0102] The sleeve 4 is fixed to the tool holder 5 by the sleeve fixing screw 32.

[0103] The upper inner side of the outer casing 10 is provided with a groove for installing the outer casing rubber sealing ring 21. The tail end of the tool bar 5 is provided with a groove for installing the tool bar tail end rubber sealing ring 27.

[0104] The circuit board base 24 is provided with threaded holes corresponding to the holes on the circuit board.

[0105] The signal processing circuit board 22 is fixed to the circuit board base 24 by hexagonal copper pillars 31.

[0106] The signal processing circuit board 22 integrates a control module 40, a signal preprocessing module 37, an analog-to-digital conversion module 36, a wireless transmission module 39, and a power supply module 38.

[0107] The power module 38 is connected to the arc-shaped lithium battery 25.

[0108] The voltage signal corresponding to the vibration sensor 17 is amplified by the signal preprocessing module 37 and then entered into the analog-to-digital conversion module 36 for encoding. The vibration sensor 17 is a three-dimensional vibration sensor.

[0109] The encoded digital signal is transmitted to the wireless transmission module 39 via SPI. The wireless transmission module 39 then transmits the encoded digital signal to the host computer.

[0110] The outer casing 10 is fixed to the tool holder 5 by the outer casing fixing screws 9.

[0111] The outer wall of the housing 10 is provided with a through hole I to fix the membrane switch 7. The membrane switch 7 is connected to the power module 38 and controls the on / off of the power supply from the lithium battery 25.

[0112] The arc-shaped lithium battery 25 is a rechargeable lithium battery, which is attached and fixed to the battery bracket 26.

[0113] The outer wall of the housing 10 is provided with a through hole II to fix the magnetic charging interface 6. The magnetic charging interface 6 is connected to the power module 38.

[0114] Example 2:

[0115] A smart vibration measuring milling cutter with symmetrically arranged sensors includes a cutting tool 1, a milling cutter head 3, a tool holder 5, a clamping component 8, a accommodating space, and a signal processing unit.

[0116] The milling cutter disc 3 is axially fixed to the head end of the cutter shank 5.

[0117] The milling cutter head 3 has multiple blades 1 evenly distributed circumferentially.

[0118] The tool holder 5 has a step machined at its head end, and a symmetrical vibration sensor mounting groove 34 is opened on the circumference of the step.

[0119] The lower end face of the vibration sensor mounting groove 34 is provided with a signal hole 16 along the axial direction of the tool bar, and the signal hole 16 leads to the tail end of the tool bar.

[0120] A radial hole 29 is opened at the tail end of the tool bar 5 at the position corresponding to the signal hole 16.

[0121] The signal hole 16 and the radial hole 29 connect the vibration sensor mounting slot 34 to the outside.

[0122] The tail end of the cutter bar 5 is provided with a housing 10.

[0123] The outer shell 10 is fixed to the tail end of the tool bar 5 by the outer shell fixing screws 9 and encloses the accommodating space.

[0124] In the accommodating space, the heat-fitted base 28 is connected to the tool holder 5 by heat fitting.

[0125] The heat-fitting base 28 is used to fix the battery bracket 26 and the circuit board base 24.

[0126] The battery holder 26 is circumferentially distributed with an array of arc-shaped lithium batteries 25.

[0127] The circuit board base 24 is used to fix the signal processing circuit board 22.

[0128] The signal processing circuit board 22 is arranged in the accommodating space.

[0129] The signal processing unit includes vibration sensors 17 symmetrically arranged at the head end of the tool holder 5.

[0130] The vibration sensor 17 is fixed in the vibration sensor mounting slot 34.

[0131] The vibration sensor 17 is connected to the signal processing circuit board 22 via a terminal lead from the terminal 35.

[0132] The terminal block 35 is placed inside the signal hole 16 and the radial hole 29.

[0133] Example 3:

[0134] A smart vibration-measuring milling cutter with symmetrically arranged sensors, with the same technical content as Embodiment 2, further describes a feature where, during machining, the cutting tool 1 experiences high-frequency collisions and compression while cutting the workpiece, leading to tool vibration. The vibration sensor 17 collects vibration signals during the cutting process. The terminal wire transmits the signal from the vibration sensor 17 to the signal processing circuit board 22 at the tail end.

[0135] The signal processing circuit board 22 amplifies and converts the signal from analog to digital, then wirelessly transmits it to the host computer via TCP / IP protocol. The host computer analyzes the cutting conditions to obtain tool condition monitoring, prediction of tool wear, and results of remaining tool life.

[0136] Example 4:

[0137] A smart vibration-measuring milling cutter with symmetrically arranged sensors, the technical content of which is the same as any one of Embodiments 2-3, further wherein the host computer analyzes the cutting conditions to obtain the results of tool condition monitoring, tool wear prediction, and remaining life as follows:

[0138] 1) Under the maximum cutting parameters within the tool's tolerance range, cut from three directions of the square workpiece, record the collected cutting signals, and select the sum of the largest vibration values ​​in the three directions as the threshold for determining whether a tool breakage has occurred.

[0139] 2) Collect different tool wear values ​​and cutting vibration signals when chatter occurs to obtain the original dataset.

[0140] 3) Perform feature extraction on the signal data collected in step 2), such as time domain analysis, frequency domain analysis, and time-frequency domain analysis, to obtain the model construction dataset.

[0141] 4) Construct an initial real-time monitoring model for tool wear and a chatter prediction model.

[0142] 5) Based on the model construction dataset, the initial real-time tool wear monitoring model and chatter prediction model are trained to obtain the trained real-time tool wear monitoring model and chatter prediction model.

[0143] 6) Real-time acquisition of tool vibration signals during tool cutting, inputting the processed signal feature set into the real-time tool wear monitoring model and chatter prediction model, performing decision analysis on the cutting conditions of the tool under test, and obtaining tool condition monitoring, prediction of tool wear and remaining life results.

[0144] Example 5:

[0145] A smart vibration measuring milling cutter with symmetrical sensor arrangement, the technical content of which is the same as any one of embodiments 2-4, further wherein the cutter bar 5 is a cylindrical strip structure and has a central through hole 20 at the center.

[0146] The milling cutter disc 3 is axially fixed to the head end of the cutter bar 5 by the milling cutter disc axial fixing screw 12, and is radially fixed by two flat key screws 14 screwed into the flat key 13.

[0147] Example 6:

[0148] A smart vibration measuring milling cutter with symmetrical sensor arrangement, the technical content of which is the same as any one of embodiments 2-5, further wherein multiple blades 1 are evenly distributed circumferentially on the milling cutter disc 3 by blade screws 2.

[0149] Example 7:

[0150] A smart vibration measuring milling cutter with symmetrical sensor arrangement, the technical content of which is the same as any one of embodiments 2-6, further wherein the vibration sensor mounting groove 34 is sealed by the sleeve 4.

[0151] The inner wall of the sleeve 4 has grooves on the upper and lower surfaces for installing the sleeve rubber sealing ring 15.

[0152] The sleeve 4 has a sleeve side through hole 11, and the tool holder 5 has a corresponding threaded hole at the corresponding height at the head end.

[0153] The sleeve 4 is fixed to the tool holder 5 by the sleeve fixing screw 32.

[0154] Example 8:

[0155] A symmetrically arranged sensor intelligent vibration measuring milling cutter, with the same technical content as any one of embodiments 2-7, further comprising a groove on the inner side of the upper end of the outer shell 10 for mounting the outer shell rubber sealing ring 21. A groove is provided at the tail end of the cutter shank 5 for mounting the cutter shank tail end rubber sealing ring 27.

[0156] The circuit board base 24 is provided with threaded holes corresponding to the holes on the circuit board.

[0157] The signal processing circuit board 22 is fixed to the circuit board base 24 by hexagonal copper pillars 31.

[0158] Example 9:

[0159] A smart vibration measuring milling cutter with symmetrical sensor arrangement, the technical content of which is the same as any one of embodiments 2-8, further wherein the signal processing circuit board 22 integrates a control module 40, a signal preprocessing module 37, an analog-to-digital conversion module 36, a wireless transmission module 39, and a power supply module 38.

[0160] The power module 38 is connected to the arc-shaped lithium battery 25.

[0161] The voltage signal corresponding to the vibration sensor 17 is amplified by the signal preprocessing module 37 and then enters the analog-to-digital conversion module 36 for encoding.

[0162] The encoded digital signal is transmitted to the wireless transmission module 39 via SPI. The wireless transmission module 39 then transmits the encoded digital signal to the host computer.

[0163] Example 10:

[0164] A smart vibration measuring milling cutter with symmetrical sensor arrangement, the technical content of which is the same as any one of embodiments 2-9, further wherein the outer shell 10 is fixed to the cutter bar 5 by the outer shell fixing screw 9.

[0165] The outer wall of the housing 10 is provided with a through hole I to fix the membrane switch 7. The membrane switch 7 is connected to the power module 38 and controls the on / off of the power supply from the lithium battery 25.

[0166] Example 11:

[0167] A smart vibration measuring milling cutter with symmetrical sensor arrangement, the technical content of which is the same as any one of embodiments 2-10, further wherein the arc-shaped lithium battery 25 is a rechargeable lithium battery and is attached and fixed on the battery bracket 26.

[0168] The outer wall of the housing 10 is provided with a through hole II to fix the magnetic charging interface 6. The magnetic charging interface 6 is connected to the power module 38.

[0169] Example 12:

[0170] A smart vibration measuring milling cutter with symmetrical sensor arrangement includes a cutting tool 1, a milling cutter head 3, a tool holder 5, a clamping component 8, a accommodating space, and a signal processing part;

[0171] The tool holder 5 is a cylindrical strip structure with a central through hole 20 at its center. The two ends of the tool holder 5 are marked as the head end and tail end, respectively. The milling cutter disc 3 is axially fixed to the head end of the tool holder 5 by milling cutter disc axial fixing screws 12, and radially fixed by two flat key screws 14 screwed into flat keys 13. Four blades 1 are evenly distributed circumferentially on the milling cutter disc 3 by blade screws 2. A step is machined at the head end of the tool holder 5, and two vibration sensor mounting slots 34, symmetrically arranged at 180°, are opened on its circumference. The vibration sensor mounting slots 34 are sealed by a sleeve 4, with two grooves on the inner wall of the sleeve 4 for installing sleeve rubber sealing rings 15. A sleeve side through hole 11 is opened on the side of the sleeve 4, and a corresponding threaded hole is opened at the corresponding height of the head end of the tool holder 5. During installation, the sleeve fixing screw 32 is screwed in first, and after the sleeve 4 is fitted, the sleeve fixing screw is tightened. 32 is screwed outward to fix the sleeve 4; the lower end face of the vibration sensor mounting groove 34 is provided with a signal hole 16 extending along the axial direction of the tool bar to the tail end of the tool bar, and a radial hole 29 is opened at the corresponding position at the tail end of the tool bar 5; the signal hole 16 needs to be machined from the end face of the head end of the tool bar 5 during machining, so the upper end face of the vibration sensor mounting groove 34 also has a through hole 18 of the same size, which is sealed by screws 19; the signal hole 16 and the radial hole 29 connect the vibration sensor mounting groove 34 and the outside; the tail end of the tool bar 5 is machined to a size that can be matched with the heat-fitting base 28; the tail end of the tool bar 5 is provided with a housing 10; the housing 10 is fixed to the tail end of the tool bar 5 by housing fixing screws 9 and encloses the accommodating space; the inner side of the upper end of the housing 10 is provided with a groove to install the housing rubber sealing ring 21; the tail end of the tool bar 5 is provided with a groove to install the tool bar tail end rubber sealing ring 27.

[0172] In the accommodating space, the heat-fitting base 28 is connected to the tool bar 5 by heat-fitting, and then the battery bracket 26 and the circuit board base 24 are fitted into it, and the two are fixed to the heat-fitting base 28 by screws 23; the battery bracket 26 is a 3D printed structure with 4 groups of 8 arc-shaped lithium batteries 25 evenly distributed around its circumference; the circuit board base 24 is provided with threaded holes corresponding to the holes of the circuit board, and after the hexagonal copper post 31 is screwed into it, the circuit board fixing screw 30 can be screwed into the hexagonal copper post 31 to fix the signal processing circuit board 22;

[0173] The signal processing unit includes two vibration sensors 17 symmetrically arranged at the head end of the tool holder 5; the vibration sensors 17 are fixed in the vibration sensor mounting slot 34 by screws 33; the signal processing circuit board 22 is arranged in the accommodating space; the vibration sensors 17 are connected to the signal processing circuit board 22 by leading out terminal wires through the wiring terminal 35; the axial signal hole 16 and radial hole 29 of the tool holder are used to accommodate the terminal wires;

[0174] The clamping component 8 is a standard BT50;

[0175] During machining, the tool rotates at high speed, and the insert 1 experiences high-frequency collisions and compression when cutting the workpiece, resulting in tool vibration. The vibration sensor 17 collects vibration signals during the cutting process. The terminal line transmits the signal from the vibration sensor 17 at the beginning to the signal acquisition and processing section at the end. The signal processing circuit board 22 amplifies and converts the signal from analog to digital, and then wirelessly transmits it to the host computer via TCP / IP protocol. The host computer analyzes the cutting conditions and obtains results such as tool condition monitoring, prediction of tool wear, and remaining life.

[0176] This embodiment provides a symmetrically arranged intelligent vibration-measuring milling cutter with sensors, capable of measuring three-dimensional vibration signals during machining in real time and uploading them to a host computer for subsequent analysis. Simultaneously, after processing and analyzing the collected signals, the machine tool can determine the machining condition of the milling cutter based on a trained artificial intelligence model, such as chipping, tool breakage, chatter, and tool wear. This embodiment achieves this by simply modifying the existing milling cutter structure, machining mounting slots and through holes, and symmetrically installing vibration sensors 17 around the circumference of the cutter shank near the machining area. This improves vibration signal acquisition while minimizing the reduction of the overall rigidity of the tool. Furthermore, the sensors, signal lines, processing circuitry, and power battery are compactly integrated onto the milling cutter, resulting in a smaller change in size and volume compared to the prototype milling cutter, thus achieving a compact structure. Moreover, by integrating wireless transmission technology, the problem of inconvenient wired transmission during high-speed rotation of the milling cutter during machining is solved, realizing the wireless capability of the intelligent milling cutter. Finally, sleeves, housings, and rubber sealing rings protect the circuit components from damage caused by chips, cutting fluid, or other interference.

[0177] The signal processing circuit board 22 integrates a control module 40, a signal preprocessing module 37, an analog-to-digital conversion module 36, a wireless transmission module 39, and a power module 38. The power module 38 is connected to the arc-shaped lithium battery 25. The two sets of voltage signals corresponding to the two vibration sensors 17 are amplified by the signal preprocessing module 37 and then enter the analog-to-digital conversion module 36 for encoding. The encoded digital signal is transmitted to the wireless transmission module 39 via SPI. The wireless transmission module 39 transmits the encoded digital signal to the host computer.

[0178] The outer wall of the housing 10 is provided with a through hole I to fix the membrane switch 7; the membrane switch 7 is connected to the power module 38 and controls the on / off of the power supply from the lithium battery 25.

[0179] The arc-shaped lithium battery 25 is a rechargeable lithium battery, which is attached and fixed to the battery bracket 26; the outer wall of the housing 10 is provided with a through hole II to fix the magnetic charging interface 6; the magnetic charging interface 6 is connected to the power module 38.

[0180] The wireless transmission module 39 communicates with the host computer via Bluetooth or WiFi.

[0181] The outer casing 10 is fixed to the tool holder 5 by the outer casing fixing screws 9.

[0182] Strain simulations of the main structure shank 5 of the prototype milling cutter and the intelligent milling cutter were performed using ANSYS. Clamping component 8 was set as a fixed support, and a pair of orthogonal radial forces and an axial force along the tool axis were applied to the tips of the two shanks. After meshing, the equivalent elastic strain of the two structures was obtained. The maximum strain of the prototype milling cutter was 0.00019139 μm, and the maximum strain of the main structure shank 5 of the intelligent milling cutter was 0.00020217 μm. As shown in Equation 1, under the same stress conditions, the maximum strain of the intelligent milling cutter increased by only 5.6% compared to the prototype milling cutter.

[0183] (1)

[0184] Two vibration sensors 17 are symmetrically arranged around the circumference of the tool holder 5, and it is assumed that the centrifugal acceleration at the sensor is... angular acceleration is In the diagram, sensor 1 is on the left and sensor 2 is on the right. These represent the tools in Vibration in three directions These represent sensor 1 in Vibrations measured in three directions Similarly, the acceleration values ​​measured by the two sensors are:

[0185] (2)

[0186] Meanwhile, since the two sensors are arranged symmetrically around the 5th circumference of the tool holder, their centrifugal acceleration and angular acceleration values ​​are the same, that is:

[0187] (3)

[0188] Therefore, from equations (2) and (3), we can obtain:

[0189] (4)

[0190] Example 13:

[0191] See Figure 10 A method for real-time monitoring of tool status and chatter identification of a smart vibration-measuring milling cutter with symmetrically arranged sensors as described in any one of Embodiments 1-12, comprising the following steps:

[0192] 1) Under the maximum cutting parameters within the tool's tolerance range, cut from three directions of the square workpiece, record the collected cutting signals, and select the sum of the largest vibration values ​​in the three directions as the threshold for determining whether a tool breakage occurs. Then, when a tool breakage occurs in actual machining, it can be judged and fed back in real time.

[0193] 2) Collect cutting vibration signals at different tool wear values ​​and when chatter occurs to obtain the raw dataset;

[0194] 3) Perform feature extraction on the signal data collected in step 2), such as time domain analysis, frequency domain analysis, and time-frequency domain analysis, to obtain the model construction dataset;

[0195] 4) Construct an initial real-time monitoring model for tool wear and a chatter prediction model;

[0196] 5) Based on the model construction dataset, the initial real-time tool wear monitoring model and chatter prediction model are trained to obtain the trained real-time tool wear monitoring model and chatter prediction model;

[0197] 6) Real-time acquisition of tool vibration signals during tool cutting, inputting the processed signal feature set into the real-time tool wear monitoring model and chatter prediction model, and performing decision analysis on the cutting conditions of the tool to be tested, so as to make accurate and real-time judgments on the amount of tool wear and whether chatter has occurred.

[0198] This embodiment, under the premise of simply machining the original milling cutter and minimally weakening its rigidity, compactly combines a vibration sensor and a signal processing circuit with an integrated wireless transmission module. It measures the three-dimensional vibration signal of the milling cutter in real time during machining and transmits it to the host computer for subsequent analysis to obtain the status of the tool, such as chipping, tool breakage, chatter, and tool wear, thereby guiding the actual machining to make corresponding improvements.

Claims

1. A smart vibration measuring milling cutter with symmetrically arranged sensors, characterized in that: Includes insert (1), milling cutter head (3), tool holder (5), clamping components (8), accommodating space and signal processing unit; The milling cutter disc (3) is axially fixed to the head end of the cutter bar (5); The milling cutter disc (3) has multiple blades (1) evenly distributed in the circumferential direction. The tool holder (5) has a step machined at its head end, and a symmetrical vibration sensor mounting groove (34) is opened on the circumference of the step. The lower end face of the vibration sensor mounting groove (34) is provided with a signal hole (16) along the axial direction of the tool bar, and the signal hole (16) leads to the tail end of the tool bar; A radial hole (29) is opened at the tail end of the tool bar (5) at the position corresponding to the signal hole (16); The signal hole (16) and the radial hole (29) connect the vibration sensor mounting slot (34) to the outside. The tail end of the cutter bar (5) is provided with a housing (10); The outer shell (10) is fixed to the tail end of the knife bar (5) by the outer shell fixing screw (9) and encloses the accommodating space; In the accommodating space, the heat-fitted base (28) is connected to the tool holder (5) by heat fitting; The heat-fitting base (28) is used to fix the battery bracket (26) and the circuit board base (24). The battery holder (26) is circumferentially distributed with an array of arc-shaped lithium batteries (25). The circuit board base (24) is used to fix the signal processing circuit board (22); The signal processing circuit board (22) is arranged in the accommodating space; The signal processing unit includes vibration sensors (17) symmetrically arranged at the head end of the tool holder (5); the vibration sensors (17) are three-dimensional vibration sensors; The vibration sensor (17) is fixed in the vibration sensor mounting slot (34); The vibration sensor (17) is connected to the signal processing circuit board (22) via a terminal lead (35); The terminal block (35) is placed inside the signal hole (16) and the radial hole (29); During machining, the cutting tool (1) experiences high-frequency collisions and compressions while cutting the workpiece, which in turn causes the tool to vibrate; the vibration sensor (17) collects the vibration signals during the cutting process; the terminal wire transmits the signal from the vibration sensor (17) to the signal processing circuit board (22) at the tail end. The signal processing circuit board (22) amplifies and converts the signal from analog to digital, and then wirelessly transmits it to the host computer via TCP / IP protocol; the host computer analyzes the cutting conditions and obtains the results of tool condition monitoring, prediction of tool wear and remaining life. The tool holder (5) is a cylindrical strip structure, and a central through hole (20) is provided at the center of the tool holder. The steps by which the host computer analyzes the cutting conditions and obtains tool condition monitoring, tool wear prediction, and remaining life results are as follows: Step 1) Cut the square workpiece from three directions at the maximum cutting parameters within the tool's tolerance range, record the collected cutting signals, and select the sum of the largest vibration values ​​in the three directions as the threshold for determining whether a tool breakage has occurred. Step 2) Collect cutting vibration signals at different tool wear values ​​and when chatter occurs to obtain the raw dataset; Step 3) Extract features from the signal data collected in Step 2) to obtain the model construction dataset; Step 4) Construct an initial real-time tool wear monitoring model and chatter prediction model; Step 5) Based on the model construction dataset, train the initial real-time tool wear monitoring model and chatter prediction model to obtain the trained real-time tool wear monitoring model and chatter prediction model; Step 6) Collect the vibration signal of the tool during the cutting process in real time, input the processed signal feature set into the real-time tool wear monitoring model and chatter prediction model, perform decision analysis on the cutting condition of the tool to be tested, and obtain the results of tool condition monitoring, prediction of tool wear and remaining life. Two vibration sensors (17) are symmetrically arranged around the circumference of the tool holder (5); Let the centrifugal acceleration at the sensor be... angular acceleration is , These represent the tools in Vibration in three directions These represent sensor I in Vibrations measured in three directions These represent sensor II in Vibrations measured in three directions; The acceleration values ​​measured by the two vibration sensors are as follows: （1） The centrifugal acceleration and angular acceleration values ​​of the two vibration sensors are the same, that is: （2） From equations (1) and (2), we get: （3）。 2. The intelligent vibration measuring milling cutter with symmetrical sensor arrangement according to claim 1, characterized in that: The milling cutter disc (3) is axially fixed to the head end of the cutter bar (5) by the milling cutter disc axial fixing screw (12), and is radially fixed by two flat key screws (14) screwed into the flat key (13).

3. The intelligent vibration measuring milling cutter with symmetrical sensor arrangement according to claim 1, characterized in that: Multiple blades (1) are evenly distributed circumferentially on the milling cutter disc (3) by blade screws (2).

4. The intelligent vibration measuring milling cutter with symmetrical sensor arrangement according to claim 1, characterized in that: The vibration sensor mounting slot (34) is sealed by a sleeve (4); The inner wall of the sleeve (4) is provided with grooves on the upper and lower surfaces for installing the sleeve rubber sealing ring (15); The sleeve (4) has a sleeve side through hole (11) on its side, and the tool bar (5) has a corresponding threaded hole at the corresponding height at its head end; The sleeve (4) is fixed to the tool holder (5) by the sleeve fixing screw (32).

5. The intelligent vibration measuring milling cutter with symmetrical sensor arrangement according to claim 1, characterized in that: The upper inner side of the outer shell (10) is provided with a groove for installing the outer shell rubber sealing ring (21); the tail end of the blade (5) is provided with a groove for installing the tail end rubber sealing ring (27). The circuit board base (24) is provided with threaded holes corresponding to the circuit board holes; The signal processing circuit board (22) is fixed to the circuit board base (24) by a hexagonal copper pillar (31).

6. The intelligent vibration measuring milling cutter with symmetrical sensor arrangement according to claim 1, characterized in that: The signal processing circuit board (22) integrates a control module (40), a signal preprocessing module (37), an analog-to-digital conversion module (36), a wireless transmission module (39), and a power supply module (38). The power module (38) is connected to the arc-shaped lithium battery (25); The voltage signal corresponding to the vibration sensor (17) is amplified by the signal preprocessing module (37), and then enters the analog-to-digital conversion module (36) for encoding; The encoded digital signal is transmitted to the wireless transmission module (39) via SPI; the wireless transmission module (39) transmits the encoded digital signal to the host computer.

7. The intelligent vibration measuring milling cutter with symmetrical sensor arrangement according to claim 1, characterized in that: The outer casing (10) is fixed to the tool bar (5) by outer casing fixing screws (9); The outer wall of the housing (10) is provided with a through hole I to fix the membrane switch (7); the membrane switch (7) is connected to the power module (38) and controls the on / off power supply of the arc lithium battery (25).

8. The intelligent vibration measuring milling cutter with symmetrical sensor arrangement according to claim 7, characterized in that: The arc-shaped lithium battery (25) is a rechargeable lithium battery, which is attached and fixed to the battery bracket (26); The outer wall of the housing (10) is provided with a through hole II to fix the magnetic charging interface (6); the magnetic charging interface (6) is connected to the power module (38).

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