A large stamping equipment tonnage detection device based on strain gauge deformation detection

Abstract

The utility model discloses a kind of large stamping equipment tonnage detection equipment based on strain gauge deformation detection, comprising: strain detection component, signal processing module, data calibration and transmission module, signal processing module and data calibration and transmission module communication connection, strain detection component includes strain gauge group, mounting column, shield plate and heat shield, strain gauge group is used to be fixed on the detection surface of force component, strain gauge group is electrically connected with signal processing module, shield plate is located on mounting column, heat shield covers strain gauge group, mounting column, shield plate.The utility model enhances anti-interference design, realizes the real-time, accurate, stable detection of the tonnage of large stamping equipment.

Description

Technical Field

[0001] This utility model belongs to the field of stamping equipment testing technology, and in particular relates to a tonnage testing device for large stamping equipment based on strain gauge deformation detection. Background Technology

[0002] Large stamping equipment is core equipment in manufacturing industries such as automobiles, shipbuilding, and aerospace. The precise control of its stamping tonnage directly determines the forming quality, dimensional accuracy, and operational safety of the stamped parts. Currently, the methods for detecting the tonnage of large stamping equipment are mainly divided into two categories: offline detection and online detection. Offline detection requires stopping the machine and using an external loading device to simulate stamping conditions, which results in long detection cycles and reduced production efficiency. Existing online detection equipment mostly uses external bolts for fixing; although it can achieve real-time detection, under the complex conditions of high-frequency impact and strong vibration in large stamping equipment, sensors are prone to drift, leading to insufficient detection accuracy and stability.

[0003] Strain gauge testing technology is widely used in the field of mechanical quantity testing due to its advantages of simple structure, rapid response and controllable cost. However, when it is applied to the tonnage testing of large stamping equipment, the following key problems are faced: strong electromagnetic interference and temperature fluctuations generated during the stamping process can easily lead to strain signal distortion and affect the testing accuracy. Summary of the Invention

[0004] The purpose of this invention is to solve the above-mentioned technical problems in the prior art and to provide a tonnage detection device for large stamping equipment based on strain gauge deformation detection, which enhances anti-interference design and realizes real-time, accurate and stable detection of the tonnage of large stamping equipment.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A tonnage detection device for large stamping equipment based on strain gauge deformation detection is characterized by comprising: a strain detection component, a signal processing module, and a data calibration and transmission module. The signal processing module and the data calibration and transmission module are communicatively connected. The strain detection component includes a strain gauge group, a mounting column, a shielding plate, and a protective shell. The strain gauge group is fixed to the detection surface of the stressed component and is electrically connected to the signal processing module. The shielding plate is mounted on the mounting column, and the protective shell covers the strain gauge group, the mounting column, and the shielding plate. This detection device features enhanced anti-interference design, enabling real-time, accurate, and stable detection of the tonnage of large stamping equipment.

[0006] Furthermore, the signal processing module includes a bridge excitation circuit, an instrumentation amplifier, a filter circuit, and an A / D conversion unit connected in series.

[0007] Furthermore, the bridge excitation circuit adopts a constant voltage excitation circuit, and the filter circuit adopts a second-order active low-pass filter circuit.

[0008] Furthermore, the data calibration and transmission module includes a microcontroller, a calibration storage unit, and a communication interface, with the microcontroller and the data calibration and transmission module communicating with each other.

[0009] Furthermore, the microcontroller uses an ARM Cortex-M4 core microcontroller, the calibration storage unit uses EEPROM, and the communication interface integrates an RS485 interface and a wireless module.

[0010] Furthermore, the strain gauge group adopts a full-bridge strain gauge, with the sensitive grid direction of the full-bridge strain gauge aligned with the axial direction of the stressed component. The full-bridge strain gauge has built-in temperature compensation capability, which has higher sensitivity and stability compared to the traditional detection method of four independent single strain gauges and temperature compensation gauges. At the same time, the structure of the full-bridge strain gauge makes it more sensitive to the small deformations of the stressed component.

[0011] Furthermore, a PCB board is mounted on the mounting column, housing the signal processing module and data calibration and transmission module. The structure is compact, the layout is reasonable, and it does not occupy a large amount of space.

[0012] Furthermore, the inner wall of the protective shell is equipped with a heat insulation layer, which ensures the heat insulation performance of the protective shell and reduces the temperature fluctuation interference generated during the stamping process.

[0013] Furthermore, the shielding plate is connected to the load-bearing component via a mounting and fixing assembly. This assembly includes a positioning bracket and a clamping bolt. The positioning bracket is located on the shielding plate, and the clamping bolt passes through the positioning bracket and is screwed onto the load-bearing component for secure fixing. This facilitates the assembly and disassembly of the strain detection component on the load-bearing component, ensuring reliable, flexible, and convenient fixing.

[0014] Furthermore, an insulating gasket is provided between the clamping bolt and the positioning bracket to prevent the formation of a current loop that could cause interference.

[0015] This utility model, by adopting the above-mentioned technical solution, has the following beneficial effects: 1. The strain gauge group adopts a full-bridge strain gauge, which has its own temperature compensation capability. Compared with the traditional detection method of four independent single strain gauges and temperature compensation gauges, it has higher sensitivity and stability. At the same time, the structure of the full-bridge strain gauge makes it more responsive to the small deformation of the stressed components. Combined with the 16-bit A / D conversion unit, it can accurately capture the subtle deformation of the stressed components of large stamping equipment during the stamping process, thereby realizing the accurate detection of stamping tonnage.

[0016] 2. The microcontroller has a built-in tonnage calibration algorithm based on the least squares method, which can calibrate the test data in real time and achieve high detection accuracy. The calibration storage unit stores calibration parameters under different working conditions, which can facilitate the equipment to quickly call the appropriate calibration parameters under different working conditions, ensuring the reliability of the test results and improving the detection efficiency. The communication interface can transmit the detected tonnage data to the equipment control cabinet or cloud monitoring platform in real time, which can help operators to keep abreast of the equipment's stamping tonnage and promptly identify and deal with potential problems.

[0017] 3. The protective shell serves to insulate heat and sound, reducing noise interference from the external environment and minimizing temperature fluctuations during the stamping process. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a circuit schematic diagram of the signal processing module in this utility model; Figure 3 This is a schematic diagram showing the arrangement of the protective shell on the load-bearing component in this utility model; Figure 4 This is a schematic diagram of the connection between the strain detection component and the mounting and fixing component in this utility model; Figure 5 for Figure 4 The main view; Figure 6 This is a schematic diagram of the arrangement of the strain gauge assembly on the stressed component in this utility model.

[0019] In the diagram: 1-Strain gauge assembly; 2-Mounting column; 3-Shielding plate; 4-Protective shell; 5-Force-bearing component; 6-Positioning hole; 7-Positioning bracket; 8-Pressure bolt; 9-PCB board; 10-Through hole. Detailed Implementation

[0020] like Figures 1 to 6 As shown, this utility model discloses a tonnage detection device for large stamping equipment based on strain gauge deformation detection, including: a strain detection component, a signal processing module, and a data calibration and transmission module. The strain detection component includes a strain gauge group 1, a mounting column 2, a shielding plate 3, and a protective shell 4. The detection surface of the force-bearing component 5 is provided with positioning holes 6 to facilitate the positioning and pasting of the strain gauge group 1 onto the detection surface of the force-bearing component 5. The strain gauge group 1 adopts a full-bridge strain gauge, and the sensitive grid direction of the full-bridge strain gauge is consistent with the axial direction of the force-bearing component 5.

[0021] The strain gauge group 1 is connected to the signal processing module, which includes a bridge excitation circuit, an instrumentation amplifier, a filter circuit, and an A / D conversion unit connected in series. The bridge excitation circuit uses a constant voltage excitation method, with an output voltage stability of ≤±0.01%, providing DC excitation for strain gauge group 1. The instrumentation amplifier has an adjustable gain range of 100-1000 times and a common-mode rejection ratio ≥120dB. The filter circuit uses a second-order active low-pass filter circuit with a cutoff frequency adjustable within the range of 100-500Hz to filter out high-frequency interference generated by stamping vibration. The A / D conversion unit has an adjustable detection range, a resolution ≥16 bits, and a sampling rate ≥800Hz, ensuring accurate real-time acquisition of minute strain signals.

[0022] The data calibration and transmission module includes a microcontroller, a calibration storage unit, and a communication interface. The microcontroller, employing an ARM Cortex-M4 core microcontroller, communicates with the A / D conversion unit via SPI or IIC interfaces. It incorporates a least-squares-based tonnage calibration algorithm, enabling real-time calibration of test data with high accuracy. The calibration storage unit uses EEPROM to store calibration parameters (including standard tonnage-strain value curves) under different operating conditions, allowing for quick retrieval of appropriate calibration parameters under varying conditions, ensuring reliable test results and improving efficiency. The communication interface integrates an RS485 interface and a wireless module, enabling real-time transmission of detected tonnage data to the equipment control cabinet or cloud monitoring platform. This allows operators to monitor the equipment's stamping tonnage in real time and promptly identify and address potential problems.

[0023] The full-bridge strain gauge has built-in temperature compensation capability, which has higher sensitivity and stability compared to the traditional detection method of four independent single strain gauges and temperature compensation gauges. At the same time, the structure of the full-bridge strain gauge makes it more responsive to the minute deformation of the stressed component 5. Combined with the 16-bit A / D conversion unit, it can accurately capture the minute deformation of the stressed component 5 of the large stamping equipment during the stamping process, thereby achieving accurate detection of the stamping tonnage.

[0024] It has both wired and wireless communication interfaces, which can be flexibly adapted to different communication scenarios in the workshop, realize the real-time display and remote traceability of tonnage data, and make it easy for equipment maintenance personnel to keep abreast of the equipment operating status and reduce equipment downtime due to failure.

[0025] The shielding plate 3 is mounted on the mounting posts 2 which are distributed on opposite sides. The shielding plate 3 is made of iron plate and is used to shield interference signals.

[0026] The shielding plate 3 is connected to the force-bearing component 5 through a mounting and fixing assembly. The mounting and fixing assembly includes a positioning bracket 7 and a clamping bolt 8. The positioning bracket 7 is fixed on the shielding plate 3 and fits against the surface of the force-bearing component 5. The clamping bolt 8 passes through the positioning bracket 7 and is screwed to the force-bearing component 5 for fixation.

[0027] By optimizing the installation structure, the strain detection component is conveniently installed and removed from the load-bearing component 5. It is fixed reliably, flexibly and conveniently, without the need for drilling, welding or other modifications to the load-bearing component 5 of the large stamping equipment. The installation time is ≤2 hours. It is compatible with large stamping equipment of different models (pull rod diameter is 50-300mm) and has strong adaptability.

[0028] An insulating gasket is provided between the clamping bolt 8 and the positioning bracket 7. The insulating gasket is made of polytetrafluoroethylene to avoid forming a current loop and causing interference.

[0029] The protective shell 4 is fixedly connected to the load-bearing component 5 by screws, which is reliable, easy to disassemble and assemble, and flexible.

[0030] The protective shell 4 covers the strain gauge assembly 1, the mounting column 2, and the shielding plate 3. The protective shell 4 can reduce noise interference from the external environment. The protective shell 4 is made of stainless steel and has reliable strength. The inner wall of the protective shell 4 is equipped with a heat insulation layer. The heat insulation layer is made of ceramic fiber and has a thickness of 2-3mm, which ensures the heat insulation performance of the protective shell 4, thereby reducing temperature fluctuation interference generated during the stamping process.

[0031] The mounting post 2 is equipped with a PCB board 9, which is located above the shielding plate 3. Both the PCB board 9 and the shielding plate 3 have through holes 10 for the wires of the transformer assembly 1 to pass through. The signal processing module and the data calibration and transmission module are mounted on the PCB board 9. The structure is compact and the layout is reasonable, without occupying a large space.

[0032] In specific implementation, the steps of this utility model are as follows: S1. Equipment Assembly: First, the surface of the load-bearing component 5 (such as the tie rod) of the large stamping equipment is ground and rust-removed. The full-bridge strain gauge is then attached to the detection surface of the tie rod, with the sensitive grid direction of the full-bridge strain gauge aligned with the tie rod's axial direction. After attachment, it is sealed with epoxy resin. Next, the protective shell 4 is placed over the outside of the strain gauge assembly 1. The heat insulation layer of the inner wall of the protective shell 4 is tightly attached to the tie rod surface. The wires of the full-bridge strain gauge pass through the through-hole 10 and connect to the signal processing module. The signal processing module and data calibration and transmission module are mounted on the PCB board 9. The positioning bracket 7 is fixed to the tie rod surface by clamping bolts 8, with an insulating gasket installed between the clamping bolts 8 and the positioning bracket 7.

[0033] S2. Parameter Calibration: After starting the equipment, the standard tonnage loading device is connected through the calibration interface of the microcontroller. Multiple sets of different standard tonnage are applied to the large stamping equipment. The digital value of the output signal of strain gauge group 1 corresponding to each set of standard tonnage is recorded after A / D conversion. The microcontroller generates the corresponding curve of "standard tonnage - strain digital value" by fitting with the least squares method. The calibration parameters are stored in EEPROM. After the calibration is completed, the standard tonnage loading device is disconnected.

[0034] S3. Tonnage Detection: When large stamping equipment is running, axial deformation is generated under the action of stamping force. The resistance value of strain gauge group 1 changes with the deformation. The full-bridge circuit converts the resistance change into a voltage signal. The bridge excitation circuit provides stable DC excitation. After the voltage signal is amplified by the instrumentation amplifier, high-frequency vibration interference is filtered out by the second-order active low-pass filter circuit. Then, it is converted into a digital signal by the 16-bit A / D conversion unit and transmitted to the microcontroller. The microcontroller calls the calibration parameters stored in the EEPROM and calculates the real-time stamping tonnage value through the calibration algorithm. On the one hand, the data is transmitted to the display screen of the workshop control cabinet for real-time display through the communication interface. On the other hand, it is uploaded to the cloud platform for data storage and traceability through the wireless module.

[0035] S4. Adaptation and Adjustment: When testing different models of large stamping equipment, remove the positioning bracket 7, replace it with a positioning bracket 7 model that matches the diameter of the tie rod, repeat the pasting and fixing process in step S1, and import the pre-stored corresponding equipment calibration parameters through the USB interface of the data calibration and transmission module to quickly complete the equipment adaptation without recalibrating.

[0036] The above are merely specific embodiments of this utility model, but the technical features of this utility model are not limited thereto. Any simple changes, equivalent substitutions, or modifications made based on this utility model to solve essentially the same technical problems and achieve essentially the same technical effects are all covered within the protection scope of this utility model.

Claims

1. A tonnage detection device for large stamping equipment based on strain gauge deformation detection, characterized in that, include: The system includes a strain gauge assembly, a signal processing module, and a data calibration and transmission module. The signal processing module and the data calibration and transmission module are communicatively connected. The strain gauge assembly includes a strain gauge group, a mounting column, a shielding plate, and a protective shell. The strain gauge group is used to fix the strain gauge group on the detection surface of the stressed component. The strain gauge group is electrically connected to the signal processing module. The shielding plate is disposed on the mounting column. The protective shell covers the strain gauge group, the mounting column, and the shielding plate.

2. The tonnage detection device for large stamping equipment based on strain gauge deformation detection according to claim 1, characterized in that: The signal processing module includes a bridge excitation circuit, an instrumentation amplifier, a filter circuit, and an A / D conversion unit connected in series.

3. The tonnage detection device for large stamping equipment based on strain gauge deformation detection according to claim 2, characterized in that: The bridge excitation circuit adopts a constant voltage excitation circuit, and the filter circuit adopts a second-order active low-pass filter circuit.

4. The tonnage detection device for large stamping equipment based on strain gauge deformation detection according to claim 1, characterized in that: The data calibration and transmission module includes a microcontroller, a calibration storage unit, and a communication interface, and the microcontroller and the data calibration and transmission module are communicatively connected.

5. The tonnage detection device for large stamping equipment based on strain gauge deformation detection according to claim 4, characterized in that: The microcontroller uses an ARM Cortex-M4 core microcontroller, the calibration storage unit uses an EEPROM, and the communication interface integrates an RS485 interface and a wireless module.

6. The tonnage detection device for large stamping equipment based on strain gauge deformation detection according to claim 1, characterized in that: The strain gauge group adopts a full-bridge strain gauge, and the sensitive grid direction of the full-bridge strain gauge is consistent with the axial direction of the stressed component.

7. The tonnage detection device for large stamping equipment based on strain gauge deformation detection according to claim 1, characterized in that: A PCB board is provided on the mounting column, and the signal processing module and the data calibration and transmission module are located on the PCB board.

8. The tonnage detection device for large stamping equipment based on strain gauge deformation detection according to claim 1, characterized in that: The inner wall of the protective shell is provided with a heat insulation layer.

9. The tonnage detection device for large stamping equipment based on strain gauge deformation detection according to claim 1, characterized in that: The shielding plate is connected to the force-bearing component through a mounting and fixing assembly. The mounting and fixing assembly includes a positioning bracket and a clamping bolt. The positioning bracket is disposed on the shielding plate, and the clamping bolt passes through the positioning bracket and is screwed and fixed to the force-bearing component.

10. A tonnage detection device for large stamping equipment based on strain gauge deformation detection according to claim 9, characterized in that: An insulating gasket is provided between the clamping bolt and the positioning bracket.

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