A high-precision bolt loosening detection device based on a magnetic encoder

Abstract

The utility model relates to a high accuracy bolt loosening detection device based on magnetic encoder, including casing and detection component, the casing includes the working cabin of setting in the casing inside and sets up the positioning portion of casing bottom, the positioning portion is used to the nut, the detection component includes magnetic encoding sensor and detection magnet, the detection magnet sets up at screw rod top, and the magnetic encoding sensor sets up in the inside of working cabin. The utility model discloses through the casing and positions the magnetic encoding sensor at the nut, detects the detection magnet fixedly installed at the bolt end through the magnetic encoding sensor, and the relative rotation of detection magnet and magnetic encoding sensor will make the periodic change of magnetic field direction or intensity, and the installation cost of magnetic encoder is low and simple, and through the change of magnetic field, further identify the angle change between the nut and screw rod, and carry out the calculation of rotation angle, based on magnetic encoder can realize 0.1 degree angle detection, improves the detection precision.

Description

Technical Field

[0001] This utility model relates to the field of bolt loosening detection technology, specifically to a high-precision bolt loosening detection device based on a magnetic encoder. Background Technology

[0002] Currently, bolt loosening detection technology is of great significance in critical structures such as mechanical equipment, bridges, and wind turbines. Traditional detection methods include vibration analysis, ultrasonic guided waves, electromechanical impedance spectroscopy, and fiber optic gratings. While these methods have achieved some success in practical applications, they generally suffer from problems such as complex installation, high cost, or insufficient accuracy.

[0003] For example, vibration analysis relies on accelerometers, which need to be installed at multiple points and combined with complex signal processing, resulting in high costs and limited sensitivity to small angle changes (such as less than 1°). While ultrasonic guided wave technology can detect looseness of about 1°, the equipment is expensive and has high requirements for environmental noise, temperature, and installation conditions.

[0004] While grating technology can achieve accuracy below 1°, its high cost and complex optical installation process limit its widespread application. Furthermore, existing technologies often rely on wired connections or complex installations, making it difficult to meet the demands of low-cost, portable monitoring in dynamic scenarios (such as wind turbine blades). Therefore, there is an urgent need for a simple, low-cost, and high-precision bolt loosening detection device to meet the dual requirements of reliability and economy in industrial applications. Utility Model Content

[0005] The first aspect of this utility model aims to solve the technical problem that the detection accuracy and detection cost cannot be balanced when detecting bolt loosening in the prior art. It provides a high-precision bolt loosening detection device based on a magnetic encoder, which can measure and detect the change in magnetic field between magnets by a magnetic encoder sensor to determine whether the bolt has become loose.

[0006] To achieve the above objectives, this utility model provides a high-precision bolt loosening detection device based on a magnetic encoder, comprising a housing and a detection assembly. The housing includes a working chamber disposed inside the housing and a positioning part disposed at the bottom of the housing, the positioning part acting on the nut. The detection assembly includes a magnetic encoder sensor and a detection magnet, the detection magnet being disposed at the top of the bolt, and the magnetic encoder sensor being disposed inside the working chamber. This solution positions the magnetic encoder sensor at the nut through the housing, and detects the detection magnet fixedly installed at the end of the bolt. When the detection magnet and the magnetic encoder sensor rotate relative to each other, the direction or intensity of the magnetic field changes periodically. The magnetic encoder has low installation cost and is simple to install. By observing the change in the magnetic field, the change in angle between the nut and the bolt is further identified, and the rotation angle is calculated. Based on the magnetic encoder, an angle detection of 0.1° can be achieved, improving the detection accuracy.

[0007] Preferably, the working chamber is equipped with a mounting platform for placing the processing circuit board. A magnetic encoding sensor is mounted on the bottom of the processing circuit board, and the magnetic encoding sensor is coaxially arranged with the bolt. Based on the magnetic encoding sensor detecting changes in the magnetic field and outputting an electrical signal, the internal processing circuit board converts the electrical signal into a digital signal and uses algorithms such as functions to calculate angle information, thereby achieving accurate measurement and output of the rotation angle.

[0008] Preferably, the bottom of the working chamber has a positioning hole, which is coaxially arranged with the magnetic coding sensor and accommodates the detection magnet; and / or, the detection magnet is a radial magnet. The detection magnet is fixed at the middle position of the screw end, so that when the working chamber is pressed against the screw end, the detection magnet can be accommodated within the range of the positioning hole, ensuring alignment between the detection magnet and the magnetic coding sensor.

[0009] The second aspect of this invention aims to solve the technical problem of inconsistent distances the screw extends to the outside. Furthermore, the housing is a cylindrical structure, and a compression spring is installed inside the housing. One end of the compression spring is fixed to the top of the housing, and the other end is connected to the working chamber. The compression spring can push the working chamber inside the housing to a position where it tightly engages with the screw.

[0010] Preferably, the housing further includes a guide assembly, which includes a first guide portion and a second guide portion. The housing is provided with the first guide portion, and the working chamber is provided with the second guide portion. The first guide portion and the second guide portion are slidably engaged along the axial direction. The first guide portion and the second guide portion of the working chamber not only make the sliding of the working chamber within the housing smoother, but the engagement of the guide assembly can also constrain the rotational movement of the working chamber during linear movement.

[0011] Preferably, the positioning part includes a constraint shell, the inner wall of which fits against the outer wall of the nut. By fitting the constraint shell onto the outer wall of the nut, the detection mechanism will not deflect relative to the nut, thus ensuring the accuracy of the detection structure.

[0012] The third aspect of this utility model aims to solve the technical problem of unstable installation of the detection device on the bolt. Furthermore, the positioning part also includes several limiting buckles, which are evenly arranged on the inner wall of the guide housing. The limiting buckles are used to act on the thread clearance of the screw. In this solution, the limiting buckles are set inside the constraint housing. When the constraint housing acts on the outer wall of the nut, the constraint buckles continuously engage with the thread clearance outside the bolt during the pressing process of the housing until the lower end face of the constraint buckle abuts against the surface of the nut, ensuring that the mounting part will not move axially after being installed on the bolt.

[0013] Preferably, the system further includes a wireless communication module and a remote server. The wireless communication module includes a first communication module and a second communication module, which are connected via communication. The first communication module is connected to the processing circuit board, and the second communication module is connected to the remote server; and / or, the wireless communication module uses a Bluetooth communication module. In this solution, the processing circuit board controls the magnetic encoder sensor to read the current detection angle at regular intervals. The processing circuit board sends data to the remote server via the wireless communication module. If the data received by the remote server exceeds a preset threshold compared to the initial reference value, the processor issues an alarm, prompting the operator to address the issue of the bolt loosening angle exceeding the threshold.

[0014] Preferably, it further includes a light-emitting component and a controller, the controller being electrically connected to the processing circuit board, the controller being used to control the light-emitting component to emit light; and / or, the light-emitting component is a light-emitting strip, a light-emitting bead, or a display screen.

[0015] Preferably, the device also includes a power supply module, which comprises a battery and a switch for turning the battery on and off. The battery is electrically connected to the magnetic coded sensor, the processing circuit board, and the wireless communication module. The power supply module supplies power to the various components within the working chamber, ensuring the stable operation of the detection device.

[0016] The beneficial effects of this utility model are as follows:

[0017] The magnetic coding sensor is positioned at the nut by the housing. The magnetic coding sensor detects the detection magnet fixedly installed at the end of the bolt. When the detection magnet and the magnetic coding sensor rotate relative to each other, the direction or intensity of the magnetic field changes periodically. By observing the change in the magnetic field, the change in the angle between the nut and the bolt can be further identified, and the rotation angle can be calculated. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of this utility model.

[0019] Figure 2 This is a cross-sectional view of the structure of this utility model.

[0020] Figure 3 This is a partial enlarged view of the structure of this utility model.

[0021] Figure 4 This is a flowchart illustrating the process of this utility model.

[0022] The reference numerals in the attached drawings include: 1. Housing; 11. First guide section; 2. Working chamber; 21. Second guide section; 22. Mounting platform; 23. Positioning hole; 3. Positioning section; 31. Constraint housing; 32. Limiting buckle; 4. Magnetic encoder sensor; 5. Detection magnet; 6. Processing circuit board; 7. Compression spring; 8. Battery. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0024] In this disclosure, unless otherwise stated, directional terms such as "inner" and "outer" are defined based on the contours of the corresponding components. Terms such as "first" and "second" used in this disclosure are for distinguishing one element from another and do not imply sequence or importance.

[0025] Example 1

[0026] like Figures 1-3As shown, this embodiment provides a high-precision bolt loosening detection device based on a magnetic encoder, including a housing 1 and a detection assembly. The housing 1 includes a working chamber 2 disposed inside the housing 1 and a positioning part 3 disposed at the bottom of the housing 1. The positioning part 3 acts on the nut. The detection assembly includes a magnetic encoder sensor 4 and a detection magnet 5. The detection magnet 5 is disposed at the top of the bolt, and the magnetic encoder sensor 4 is disposed inside the working chamber 2. In this solution, the magnetic encoder sensor 4 is positioned at the nut by the housing 1. The magnetic encoder sensor 4 detects the detection magnet 5 fixedly installed at the end of the bolt. When the detection magnet 5 and the magnetic encoder sensor 4 rotate relative to each other, the direction or intensity of the magnetic field changes periodically. The magnetic encoder has low installation cost and is simple to install. By observing the change in the magnetic field, the change in angle between the nut and the bolt can be further identified, and the rotation angle can be calculated. Based on the magnetic encoder, an angle detection of 0.1° can be achieved, thus improving the detection accuracy.

[0027] The working chamber 2 is equipped with a mounting platform 22 for placing the processing circuit board 6. A magnetic encoder sensor 4 is mounted on the bottom of the processing circuit board 6, and the magnetic encoder sensor 4 is coaxially arranged with the bolt. Based on the magnetic encoder sensor 4 detecting changes in the magnetic field and outputting an electrical signal, the internal processing circuit board 6 converts the electrical signal into a digital signal and uses algorithms such as functions to calculate angle information, thereby realizing the accurate measurement and output of the rotation angle.

[0028] The bottom of the working chamber 2 has a positioning hole 23, which is coaxially arranged with the magnetic coding sensor 4. The positioning hole 23 accommodates the detection magnet 5, which is a radial magnet. The detection magnet 5 is fixed at the middle position of the end of the screw, so that when the working chamber 2 is pressed against the end of the screw, the detection magnet 5 can be accommodated within the range of the positioning hole 23, ensuring that the detection magnet 5 and the magnetic coding sensor 4 are aligned.

[0029] The detection magnet 5 and the magnetic encoder sensor 4 together form a magnetic encoder. The magnetic encoder can be replaced with different models and principles, such as AS5600 (Hall effect), SD2315 (GMR), MT6825 (AMR), TAD2141 (TMR), or other angle encoders based on magnetic fields, which can be selected according to different accuracy requirements.

[0030] Furthermore, in this embodiment, the housing 1 has a cylindrical structure, and a compression spring 7 is installed inside the housing 1. One end of the compression spring 7 is fixed to the top of the housing 1, and the other end of the compression spring 7 is connected to the working chamber 2. The compression spring 7 can push the working chamber 2 inside the housing 1 to a position that is tightly engaged with the screw, which can solve the technical problem of inconsistent distances of the screw extending to the outside.

[0031] The housing 1 further includes a guide assembly, which comprises a first guide portion 11 and a second guide portion 21. The housing 1 is provided with the first guide portion 11, and the working chamber 2 is provided with the second guide portion 21. The first guide portion 11 and the second guide portion 21 are slidably engaged along the axial direction. The first guide portion 11 and the second guide portion 21 of the working chamber 2 not only make the sliding of the working chamber 2 within the housing 1 smoother, but also the engagement of the guide assembly can constrain the rotational movement of the working chamber 2 during linear movement.

[0032] In this embodiment, the outer wall of the working chamber 2 is provided with an arc-shaped guide groove along the axial direction as a second guide part 21, and the inner wall of the shell 1 is provided with a strip-shaped protrusion along the axial direction. The guide groove accommodates the strip-shaped protrusion, and the guide groove and the strip-shaped protrusion cooperate with each other, so that the first guide part 11 and the second guide part 21 are in sliding engagement. In addition, the first guide part 11 can also be a guide rod, and the second guide part 21 of the working chamber 2 has a guide hole inside it, and the guide rod is inserted into the guide hole for sliding engagement.

[0033] Example 2

[0034] Based on Example 1, such as Figures 1-3 As shown, the positioning part 3 in this embodiment includes a constraint shell 31, the inner wall of which fits against the outer wall of the nut. By fitting the constraint shell 31 onto the outer wall of the nut, the detection mechanism will not deflect relative to the nut, thus ensuring the accuracy of the detection structure.

[0035] like Figures 2-3 As shown, the positioning part 3 also includes a plurality of limiting buckles 32, which are evenly arranged on the inner wall of the guide housing. The limiting buckles 32 are used to act on the thread clearance of the screw.

[0036] The limiting buckle 32 is set inside the constraint housing 31. When the constraint housing 31 acts on the outer wall of the nut, the constraint buckle continuously engages with the thread gap outside the bolt during the pressing process of the housing 1 until the lower end face of the constraint buckle abuts against the surface of the nut, so that the mounting part will not move axially after it is installed on the bolt.

[0037] Example 3

[0038] Based on Example 1, such as Figure 4As shown, this embodiment also includes a wireless communication module and a remote server. The wireless communication module includes a first communication module and a second communication module, which are connected via communication. The first communication module is connected to the processing circuit board 6, and the second communication module is connected to the remote server. The wireless communication module uses Bluetooth communication. In this embodiment, the processing circuit board 6 controls the magnetic encoder sensor 4 to read the current detection angle at regular intervals. The processing circuit board 6 sends the collected data to the remote server via the wireless communication module. If the data received by the remote server exceeds a preset threshold compared to the initial reference value, the processor issues an alarm, prompting the operator to address the issue of the bolt loosening angle exceeding the threshold.

[0039] The remote server can connect to a monitor and display alarm information when an alarm signal is triggered. In addition, the remote server can also connect to speakers, alarm lights, or voice prompts to provide alarm information.

[0040] In addition, the wireless communication module can also be an RS-485 module, a CAN bus module, an Ethernet module, a 4G communication module, a 5G communication module, a Zigbee module, a Wi-Fi module, an NB-IoT module, or a LoRa module.

[0041] like Figure 4 As shown, this embodiment also includes a light-emitting component and a controller. The controller is electrically connected to the processing circuit board and is used to control the light-emitting component to emit light. The controller receives data collected by the processing circuit board 6 and also has the same rotation determination and recognition function as the remote processor. When the data information received by the controller exceeds a preset threshold compared with the initial reference value, the controller controls the light-emitting component to provide a light prompt. In this embodiment, the light-emitting component is installed on the side wall of the working chamber 2 of the detection device. The light emitted by the light-emitting component facilitates manual inspection and allows for quick on-site location based on the alarm signal from the remote server.

[0042] The light-emitting component can be a light strip, a light bead, or a display screen. The light-emitting component can alert inspection personnel by turning on the light or changing the light color. If the light is changed, the light can be set to green when no rotational looseness is detected, and the light can be set to green when rotational looseness is detected. The specific color can be adapted to the specific scenario.

[0043] It also includes a power supply module, which comprises a battery 8 and a switch for turning the battery 8 on and off. The battery 8 is electrically connected to the magnetic code sensor 4, the processing circuit board 6, and the wireless communication module. The power supply module supplies power to various components inside the working chamber 2, ensuring the stable operation of the detection device.

[0044] The battery 8 can be equipped with a charging interface, which is located on the side wall of the work compartment for easy charging or wiring. When the detection device is used for outdoor mechanical equipment, the battery 8 can also be powered by solar energy.

[0045] The processing circuit board 6 employs components such as an AD converter and arithmetic circuits. When the detection magnet 5 and the magnetic encoding sensor 4 rotate relative to each other, a change in the magnetic field is generated. The magnetic encoding sensor 4 detects this change and converts it into an electrical signal, which is then converted into a digital signal by the processing circuit board 6. Finally, the arithmetic circuit uses a function to calculate and output angle information. Furthermore, the processing circuit board 6 can control the activation and deactivation of the magnetic encoding sensor 4, activating it at preset time intervals for detection. This results in greater power saving, lower power consumption, and extended operating time of the detection device.

[0046] Furthermore, this embodiment also includes a reference identification module. This module detects the measurement result between the magnet 5 and the magnetic code sensor 4 when the bolt is tightened to the correct position. The measurement result from the reference identification module serves as the reference value. The reference identification module can be activated by an external trigger switch. On one hand, after the bolt is tightened and the detection device is installed, the reference identification module is activated by the trigger switch to identify the reference value. On the other hand, if the bolt becomes loose, and the inspection personnel arrive and retighten the bolt, the reference value needs to be re-identified by activating the trigger switch. In addition, the reference identification module can also be connected to the first communication module, enabling it to receive information from a remote server to re-identify the reference value and re-identify it as the reference value.

[0047] In addition, the detection device integrates a temperature sensor to monitor the ambient temperature in real time and corrects minute angular errors caused by temperature changes through a temperature compensation algorithm.

[0048] The top of the working chamber 2 in this embodiment is provided with a removable cover, and the top of the housing 1 is provided with a removable cover. When the battery 8 of the power supply equipment is low or the internal components of the testing equipment are damaged, the battery 8 or the damaged components can be replaced without changing the installation state of the testing equipment on the bolts by removing the cover and taking out the compression spring 7 and the cover in sequence, or by taking out the compression spring 7 and the working chamber 2 in sequence. This can meet the long-term use of a single testing equipment.

[0049] In one embodiment, the detection device is installed on a wind turbine blade bolt (M20 specification). A detection magnet 5 is fixed to the tail of the bolt. After installation, the initial angle is recorded as 0° by a magnetic coding sensor 4. The sampling interval is set to 4 hours. A temperature compensation algorithm calibrates the angle based on the real-time ambient temperature. During the test, the bolt is manually loosened by 0.1°. The detection device detects the angle change during the next sampling and sends the monitored data to a remote server via Bluetooth. The remote server identifies the rotation angle and determines whether the change triggers an alarm. In another embodiment, the test is conducted on a bridge connection bolt (M30 specification). The sampling interval is set to 6 hours, and the data is sent to a remote server via 5G signal to dynamically monitor the angle loosening of all bolts.

[0050] The above descriptions are merely embodiments of this utility model, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of this utility model, and these should also be considered within the scope of protection of this utility model. These modifications will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application shall be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A high-precision bolt loosening detection device based on a magnetic encoder, characterized in that: The device includes a housing (1) and a detection assembly. The housing (1) includes a working chamber (2) disposed inside the housing (1) and a positioning part (3) disposed at the bottom of the housing (1). The positioning part (3) acts on the nut. The detection assembly includes a magnetic coding sensor (4) and a detection magnet (5). The detection magnet (5) is disposed at the top of the screw, and the magnetic coding sensor (4) is disposed inside the working chamber (2).

2. The high-precision bolt loosening detection device based on a magnetic encoder according to claim 1, characterized in that: The working chamber (2) is equipped with a mounting platform (22) for placing the processing circuit board (6). A magnetic coding sensor (4) is installed on the bottom of the processing circuit board (6), and the magnetic coding sensor (4) is coaxially arranged with the bolt.

3. The high-precision bolt loosening detection device based on a magnetic encoder according to claim 2, characterized in that: The bottom of the working chamber (2) is provided with a positioning hole (23), which is coaxially arranged with the magnetic coding sensor (4) and accommodates the detection magnet (5); and / or, the detection magnet (5) is a radial magnet.

4. The high-precision bolt loosening detection device based on a magnetic encoder according to claim 1, characterized in that: The shell (1) is a cylindrical structure. A compression spring (7) is installed inside the shell (1). One end of the compression spring (7) is fixed to the top of the shell (1), and the other end of the compression spring (7) is connected to the working chamber (2).

5. A high-precision bolt loosening detection device based on a magnetic encoder according to claim 4, characterized in that: The housing (1) further includes a guide assembly, which includes a first guide portion (11) and a second guide portion (21). The housing (1) is provided with the first guide portion (11), and the working chamber (2) is provided with the second guide portion (21). The first guide portion (11) and the second guide portion (21) slide together along the axial direction.

6. The high-precision bolt loosening detection device based on a magnetic encoder according to claim 1, characterized in that: The positioning part (3) includes a constraint shell (31), the inner wall of which is fitted with the outer wall of the nut.

7. A high-precision bolt loosening detection device based on a magnetic encoder according to claim 6, characterized in that: The positioning part (3) also includes a number of limiting buckles (32), which are evenly arranged on the inner wall of the guide shell. The limiting buckles (32) are used to act on the thread clearance of the screw.

8. A high-precision bolt loosening detection device based on a magnetic encoder according to claim 1, characterized in that: It also includes a wireless communication module and a remote server. The wireless communication module includes a first communication module and a second communication module, which are connected by communication. The first communication module is connected to the processing circuit board (6), and the second communication module is connected to the remote server; and / or, the wireless communication module adopts a Bluetooth communication module.

9. A high-precision bolt loosening detection device based on a magnetic encoder according to claim 1, characterized in that: It also includes a light-emitting component and a controller, the controller being electrically connected to the processing circuit board (6), the controller being used to control the light-emitting component to emit light; and / or, the light-emitting component is a light-emitting strip, a light-emitting bead, or a display screen.

10. A high-precision bolt loosening detection device based on a magnetic encoder according to claim 1, characterized in that: It also includes a power supply module, which includes a battery (8) and a switch for turning the battery (8) on and off. The battery (8) is electrically connected to the magnetic encoder sensor (4), the processing circuit board (6) and the wireless communication module.

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