A smart drill rod for deep hole machining

Abstract

This application relates to the field of deep hole drill pipe technology and discloses an intelligent drill pipe for deep hole machining, including a drill pipe body, monitoring devices and sensors arranged on the drill pipe body, and an information transmission device. The monitoring devices and sensors include strain gauges and accelerometers, which are used to collect physical signals from the actual machining conditions, such as cutting force, torque, and high-frequency vibration, in real time during deep hole machining. The information transmission device wirelessly transmits the collected signals to an external computer system. This invention uses monitoring signal algorithms to intuitively reflect machining conditions such as tool wear and chatter, and converts the status monitoring results into control commands that are transmitted to the machine tool system. This achieves closed-loop control of deep hole machining from multi-source signal acquisition and status recognition to adaptive control of machining parameters, overcoming the problem of unobservable machining conditions and improving machining quality and intelligence.

Description

Technical Field

[0001] The present invention relates to the technical field of deep hole drill pipes, and specifically to an intelligent drill pipe for deep hole machining. Background Art

[0002] Hole machining is an extremely crucial machining task in the field of mechanical machining. With the development of modern manufacturing industry and the improvement of market demand, deep hole machining technology has become the dominant technology for hole machining, and is widely used in the manufacturing of parts such as large diesel engines, aerospace engines, gun barrels, etc., which is crucial for fields such as shipbuilding, aerospace, and weaponry. The quality of precision deep hole machining directly determines the assembly performance and service reliability of products.

[0003] Due to the special characteristics of large length-diameter ratio and closed cutting area in deep hole machining, there are many technical problems: the cutting tool penetrates deep into the workpiece, and the cutting state and the machining environment inside the hole cannot be directly observed, making it difficult to judge the rationality of machining parameters, resulting in difficult parameter adjustment and difficult to guarantee the quality of the hole wall.

[0004] Traditional production relies on manual experience to judge the machining state, which is highly subjective and has poor generality. The experience fails after changing materials or cutting tools, and it does not conform to the trend of digitization and intelligence; off-line detection can only evaluate the quality after machining, and cannot obtain the working conditions in real time and dynamically adjust the process, making it difficult to meet the requirements of high-precision and high-efficiency machining. Therefore, the online real-time monitoring technology for deep hole machining urgently needs to be broken through. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides an intelligent drill pipe for deep hole machining, which solves the problem that machining parameters cannot be optimized online by integrating a sensing and transmission module on the drill pipe structure.

[0006] To achieve the above objectives, the present invention is realized through the following technical solutions: an intelligent drill pipe for deep hole machining, including a drill pipe body, a monitoring device sensor arranged on the drill pipe body, and an information transmission device. Both ends of the drill pipe body are provided with end internal thread structures. The monitoring device sensor includes a strain gauge 1 arranged at the first position of the drill pipe body. The information transmission device includes a wireless transmission module 1 that is matched with the strain gauge 1. The wireless transmission module 1 is used to transmit the collected signals to an external computer system. The monitoring device sensor and the information transmission device are powered by a micro battery installed on the drill pipe body or obtain energy through an electromagnetic induction power supply method. An installation position is provided inside the drill pipe body, and the micro battery, the monitoring device sensor, and the information transmission device are hermetically embedded and installed in the installation position.

[0007] Preferably, the length-diameter ratio of the drill pipe body is greater than 5, and the installation position is provided with a sealing cover plate flush with the outer circumferential surface of the drill pipe body to maintain the hydrodynamic performance and structural rigidity of the drill pipe surface.

[0008] Preferably, the monitoring device sensor further includes a strain gauge two arranged at a second position on the drill pipe body.

[0009] Preferably, the information transmission device further includes a second wireless transmission module connected to the second strain gauge signal. Both the first wireless transmission module and the second wireless transmission module transmit real-time data to an external computer system via wireless communication through the gap between the drill rod and the workpiece hole wall.

[0010] Preferably, strain gauge one and strain gauge two are symmetrically distributed along the circumference of the drill rod.

[0011] Preferably, the monitoring device also includes an acceleration sensor arranged on the drill rod body near the cutting tool end.

[0012] Preferably, the information transmission device further includes a wireless transmission module three connected to the acceleration sensor signal, the wireless transmission module three transmitting the vibration signal to an external computer system via wireless communication through the gap space between the drill rod and the workpiece hole wall.

[0013] Preferably, the external computer system is equipped with adapter software, which has a built-in signal processing algorithm. The external computer system transmits control commands to the machine tool control system through its industrial bus interface to adjust the machining parameters in real time.

[0014] Preferably, the adapter software includes a real-time visualization window for acquiring signals, used to display various signal waveforms acquired by the sensor in real time.

[0015] Preferably, the data for the built-in signal processing algorithm in the adapter software of the external computer system all come from the actual cutting conditions. The external computer system calculates and reflects the current machining state (such as normal cutting, tool wear, chip blockage, or abnormal chatter) in real time based on the cutting force and torque signals collected by strain gauges and the vibration signals collected by acceleration sensors. Based on the machining state monitoring results, the external computer system generates control commands containing spindle speed or feed adjustment information and transmits them to the machine tool control system in real time through the industrial bus interface, thereby forming a closed-loop parameter control based on the actual machining state.

[0016] This invention provides an intelligent drill rod for deep hole machining. It has the following beneficial effects: 1. This invention integrates sensors and wireless information transmission devices directly onto the drill rod body with a large length-to-diameter ratio to collect multi-source physical signals such as cutting force, torque, and vibration during the deep hole machining process in real time, and transmits them to an external computer system for graphical display. This effectively overcomes the technical difficulty of the cutting state being unable to be directly observed when the tool is deep inside the workpiece during deep hole machining, transforming the invisible machining conditions into an intuitive data model, and truly realizing real-time online visualization of the deep hole machining process.

[0017] 2. This invention accurately identifies actual machining conditions such as tool wear, chip blockage, and abnormal chatter by real-time acquisition and algorithm feature analysis of multi-source signals originating from actual physical working conditions, such as cutting force, torque, and high-frequency acceleration vibration. The monitoring results are directly converted into control commands and quickly fed back to the machine tool actuator, achieving the effect of adaptive and dynamic closed-loop control of machining parameters such as spindle speed and feed rate. This not only gives the front-end monitoring data strong engineering implementation and practical value, but also fundamentally solves the technical pain point of traditional deep hole machining that relies too much on manual experience and cannot optimize parameters online.

[0018] 3. By upgrading traditional purely mechanical deep hole drill rods to intelligent equipment with status perception and data interaction capabilities, based on real-time monitoring and timely feedback control of cutting force and vibration signals, it can effectively avoid or reduce situations such as off-center loading and abnormal chatter during processing, thereby reliably ensuring the quality and precision of the machined hole surface. This not only meets the advanced deep hole processing requirements of high precision, high quality, and high efficiency, but also significantly improves the digitalization and intelligence level of deep hole processing operations. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the intelligent drill rod for deep hole machining according to the present invention; Figure 2 This is a schematic diagram of the distributed arrangement of the multi-strain gauges of the present invention; Figure 3 This is a schematic diagram of the combined arrangement of strain gauges and acceleration sensors of the present invention.

[0020] The components include: 1. Drill rod body; 2. Monitoring device sensor; 3. Information transmission device; 4. External computer system; 5. Adaptor software; 6. Real-time visualization window for acquired signals; 7. Deep hole machining status monitoring result window; 8. End internal thread structure; 9. Strain gauge one; 10. Wireless transmission module one; 11. Strain gauge two; 12. Wireless transmission module two; 13. Accelerometer; 14. Wireless transmission module three. Detailed Implementation

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example

[0022] like Figure 1 As shown, this embodiment discloses an intelligent drill rod for deep hole machining. The whole is composed of a drill rod body 1, a monitoring device sensor 2, an information transmission device 3, and an external computer system 4. The drill rod body 1 is made of high-strength alloy structural steel for deep hole machining, which has high rigidity, low vibration, and fatigue resistance. The length-to-diameter ratio of the rod body is greater than 5, which meets the requirements of deep hole machining. The drill rod body 1 has end internal thread structures 8 machined at both ends. The front internal thread is used to assemble cutting tools such as deep hole drills, reamers, or boring tools, and the rear internal thread is used to rigidly connect with the output end or intermediate rod of the machine tool spindle to ensure stable transmission torque and high coaxiality accuracy.

[0023] The monitoring device sensor 2 includes strain gauge 9, and the information transmission device 3 includes a wireless transmission module 10 that is compatible with strain gauge 9. Strain gauge 9 adopts a patch structure and is fixed to the first position of drill rod body 1 by high temperature resistant and vibration resistant adhesive, such as the stress concentration area in the middle section of drill rod body 1, for example, to collect cutting force and torque signals during the processing. The wireless transmission module 10 is installed near strain gauge 9.

[0024] To avoid the metal rod completely shielding the wireless signal, the transmitting antenna of the wireless transmission module 10 is positioned close to the sealing cover at the mounting location, allowing the signal to be transmitted to the outside through the annular gap between the drill rod and the workpiece hole wall. Specifically, an O-ring is provided between the sealing cover and the mounting location, and it is fixed with high-strength non-metallic screws or chemical adhesives. The sealing cover is made of high-strength ceramic or reinforced polyetheretherketone and other non-metallic wave-transparent materials, and its mechanical strength is sufficient to withstand the impact of high-pressure coolant and centrifugal force during deep hole machining. The curvature of the outer surface of the cover is consistent with the outer diameter curvature of the drill rod 1, ensuring that the normal backflow and chip removal of coolant in the annular gap are not interfered with.

[0025] Furthermore, considering that the presence of cutting fluid and chips inside the hole during deep hole machining may cause high-frequency wireless signal attenuation, the wireless transmission module 10 supports multi-band adaptive switching. Under normal hole depths, Bluetooth or Wi-Fi bands can be used; when machining extremely deep holes, the module can switch to low-frequency radio bands (such as the Sub-1GHz band) to enhance the penetration and diffraction transmission capability of cutting fluid inside the hole; or, the information transmission device 3 integrates a micro storage chip, which caches real-time data locally when the wireless signal is temporarily interrupted, and performs intermittent retransmission when the machine stops and the tool is retracted or the signal is restored to ensure that the data is not lost.

[0026] The monitoring device sensor 2 and the information transmission device 3 are powered by a micro battery installed on the drill rod body 1. The micro battery and the sensor assembly are encapsulated together in a waterproof and shockproof cavity and embedded in the mounting position of the drill rod body 1. This mounting position avoids the coolant channel inside the drill rod. When the drill rod rotates, the assembly rotates synchronously with the drill rod body 1. It can also obtain energy through electromagnetic induction power supply to meet the energy demand under the following rotation condition.

[0027] When electromagnetic induction power is used, a receiving coil is wound on the outer circumference of the tail of the drill rod 1 before it enters the hole. A corresponding transmitting coil is provided on the stationary parts of the machine tool, such as the drill rod support or guide sleeve. The transmitting coil is connected to an external high-frequency AC power supply to generate an alternating magnetic field. When the drill rod rotates, the receiving coil on it cuts the magnetic field lines or generates an induced electromotive force through magnetic field coupling. After rectification and voltage reduction, it charges the micro battery or directly powers the sensor and wireless transmission module.

[0028] The external computer system 4 includes an industrial computer and pre-installed adapter software 5. The adapter software 5 has a real-time visualization window 6 for acquired signals and a deep hole machining status monitoring result window 7, which can display the time-domain curves and values ​​of cutting force and torque in real time. It also has built-in neural networks and deep learning algorithms for signal feature extraction, working condition identification, and anomaly judgment. The specific processing process of the neural network and deep learning algorithm built into the adapter software 5 is as follows: the time-domain signals collected by the strain gauge and accelerometer 13 are used as input, and they are subjected to fast Fourier transform or wavelet transform to extract the frequency domain features and time-frequency features of cutting force, torque, and vibration signals, such as the energy ratio of specific frequency bands and peak factor, as feature vectors. The feature vectors are then input into a convolutional neural network or long short-term memory network classification model that has been trained using a large amount of historical data of deep hole machining (labeled with normal cutting, tool wear, chip blockage, abnormal chatter, etc.). The model outputs the current deep hole machining status identification result in real time and compares it with the preset safety threshold.

[0029] During processing, strain gauge 9 collects signals in real time and sends them to wireless transmission module 10. Wireless transmission module 10 transmits the real-time data to external computer system 4. External computer system 4 processes and identifies the status through adapter software 5. When the system detects an abnormality, it automatically generates control commands and transmits them to the machine tool control system through the industrial bus interface of external computer system 4 to adjust the spindle speed or feed rate in real time, thereby achieving closed-loop control.

[0030] The specific control logic is as follows: When the system identification result is "chatter warning", the external computer system 4 issues an instruction to make the machine tool spindle speed fluctuate in a step manner within the range of ±5%-10% according to the preset vibration-speed mapping model, so as to destroy the resonance condition; when the identification result is "severe tool wear", the system automatically reduces the feed rate and prompts tool change in the real-time visualization window 6 of the acquired signal; when the identification result is "poor chip removal leading to torque surge", the system instantly increases the coolant pressure and reduces the feed rate until the torque recovers to the safe threshold. Example

[0031] like Figure 2 As shown, the difference between this embodiment and embodiment 1 is that: the monitoring device sensor 2 adds a strain gauge 2 11 arranged at the second position of the drill rod body 1, and the information transmission device 3 adds a wireless transmission module 2 12 accordingly. The strain gauge 1 9 and strain gauge 2 11 are symmetrically distributed circumferentially along the drill rod body 1, that is, the first position and the second position are circumferentially symmetrically distributed, and respectively collect the cutting force and axial force in different directions to form multi-dimensional force sensing. The wireless transmission module 1 10 and the wireless transmission module 2 12 are independently connected to the corresponding strain gauges, supporting the synchronous acquisition and parallel transmission of multiple signals and avoiding signal crosstalk.

[0032] By using multi-point measurements distributed around the circumference, eccentric interference during drill rod rotation can be effectively compensated. When an off-center load or abnormal vibration is detected, the system generates instructions and feeds them back to the machine tool control system through the industrial bus interface, ensuring machining stability and improving the roundness and straightness of the hole. Example

[0033] like Figure 3 As shown, this embodiment is a further optimization based on embodiment 2, integrating multi-source sensing components and configuring strain gauge 1 9, strain gauge 2 11 and acceleration sensor 13, and respectively matching independent wireless transmission module 1 10, wireless transmission module 2 12 and wireless transmission module 3 14.

[0034] Strain gauge 9 and strain gauge 11 are responsible for acquiring load signals; accelerometer 13 is fixed to the drill rod body 1 near the tool end and is used to acquire high-frequency vibration and impact signals.

[0035] During the processing, all sensors upload signals in parallel through their respective connected wireless transmission modules. The external computer system 4 uses the adapter software 5 to fuse the multi-source signals and combine force and vibration characteristics to make accurate judgments. For example, the high-frequency signal collected by the acceleration sensor 13 can identify chatter initiation or chip blockage earlier. After identifying the abnormality, the system immediately generates optimization instructions and sends them back through the industrial bus interface to quickly adjust the processing parameters, achieving high-precision and high-reliability closed-loop intelligent control of deep hole processing throughout the process.

[0036] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A smart drill rod for deep hole machining, characterized in that, The system includes a drill rod body (1), a monitoring device sensor (2) arranged on the drill rod body (1), and an information transmission device (3). Both ends of the drill rod body (1) are provided with end internal thread structures (8). The monitoring device sensor (2) includes a strain gauge (9) arranged at a first position on the drill rod body (1). The information transmission device (3) includes a wireless transmission module (10) that is matched with the strain gauge (9). The wireless transmission module (10) is used to transmit the collected signal to an external computer system (4). The monitoring device sensor (2) and the information transmission device (3) are powered by a micro battery installed on the drill rod body (1) or obtain energy through electromagnetic induction power supply. The drill rod body (1) is provided with an installation position. The micro battery, the monitoring device sensor (2), and the information transmission device (3) are sealed and embedded in the installation position.

2. The intelligent drill rod for deep hole machining according to claim 1, characterized in that, The length-to-diameter ratio of the drill rod body (1) is greater than 5, and the mounting position is provided with a sealing cover plate that is flush with the outer circumferential surface of the drill rod body (1) to maintain the hydrodynamic performance and structural rigidity of the drill rod surface.

3. The intelligent drill rod for deep hole machining according to claim 1, characterized in that, The monitoring device sensor (2) also includes a strain gauge two (11) arranged at the second position of the drill rod body (1).

4. The intelligent drill rod for deep hole machining according to claim 3, characterized in that, The information transmission device (3) also includes a wireless transmission module (12) that is connected to the strain gauge (11) via signal. Both the wireless transmission module (10) and the wireless transmission module (12) transmit real-time data to an external computer system (4) via wireless communication using the gap between the drill rod and the workpiece hole wall.

5. The intelligent drill rod for deep hole machining according to claim 4, characterized in that, The strain gauge 1 (9) and strain gauge 2 (11) are symmetrically distributed along the circumference of the drill rod body (1).

6. The intelligent drill rod for deep hole machining according to claim 1, characterized in that, The monitoring device sensor (2) also includes an acceleration sensor (13) arranged on the drill rod body (1) near the cutting tool end.

7. The intelligent drill rod for deep hole machining according to claim 6, characterized in that, The information transmission device (3) also includes a wireless transmission module three (14) connected to the acceleration sensor (13) signal. The wireless transmission module three (14) transmits the vibration signal to the external computer system (4) through the gap space between the drill rod and the workpiece hole wall in a wireless communication manner.

8. The intelligent drill rod for deep hole machining according to claim 1, characterized in that, The external computer system (4) is equipped with adapter software (5), which has a built-in signal processing algorithm. The external computer system (4) transmits control commands to the machine tool control system through its industrial bus interface to adjust the processing parameters in real time.

9. A smart drill rod for deep hole machining according to claim 8, characterized in that, The adapter software (5) includes a real-time visualization window (6) for acquiring signals, which is used to display various signal waveforms acquired by the sensor in real time.

10. A smart drill rod for deep hole machining according to claim 8, characterized in that, The adapter software (5) also includes a deep hole machining status monitoring result window (7) for outputting status identification and early warning information.

Images