Bolt intelligent tightening system and tightening quality online analysis method

Abstract

The application discloses a bolt intelligent tightening system and a tightening quality online analysis method, which comprises a bolt head fixing clamp for fixing a bolt head; a first connecting piece provided with a through hole for the bolt body to pass through; a tightening device for tightening and loosening a nut and an end of the bolt body away from the bolt head; a sliding guide rail connected with the tightening device in sliding mode; a shooting unit fixedly connected with the sliding guide rail; a horizontal thrust unit connected with the sliding guide rail and the tightening device; an up-down thrust unit connected with the horizontal thrust unit; and a control unit connected with the shooting unit, the tightening device, the horizontal thrust unit and the up-down thrust unit, respectively, for controlling the horizontal thrust unit and the up-down thrust unit to adjust the position of the tightening device and controlling the working state of the tightening device based on the real-time position of the nut shot by the shooting unit. The application can realize intelligent positioning of the tightening device in the bolt tightening process, has simple structure, is easy to realize and is suitable for wide application.

Description

Technical Field

[0001] This invention belongs to the field of intelligent bolt tightening, specifically relating to an intelligent bolt tightening system and an online method for analyzing tightening quality. Background Technology

[0002] Bolted connections are widely used in various engineering machinery products due to their advantages such as high load-bearing capacity and ease of assembly and disassembly. As a weak link in the system, their assembly quality directly determines the overall performance of the engineering machinery product. Bolted connections rely on manual tightening, which is labor-intensive and the tightening quality is uncontrollable. With the development of intelligent manufacturing technologies such as machine vision guidance, automatic tightening, and big data, bolt tightening has initially achieved automated tightening based on machine vision guidance. However, the judgment of the tightening process quality still relies on the single parameter of torque, lacking analysis of key tightening parameters (angle, slope, etc.). Abnormal tightening such as jamming and yielding during the tightening process cannot be effectively identified, leading to loosening and breakage of bolt connections. Based on visual intelligent guidance, online analysis of multiple parameters in the tightening process can achieve intelligent control of the tightening process, integrating automated tightening technology with big data technology. This is of great significance for improving the reliability of connection systems. Unfortunately, at present, there is no effective intelligent tightening device or online tightening quality analysis method to achieve intelligent bolt tightening and online quality judgment.

[0003] Currently, there are few publicly available reports and literature on intelligent bolt tightening systems and online tightening quality analysis methods. International research in this area is largely kept confidential. Domestically, some technical research has been conducted in the automotive, aerospace, and other fields regarding intelligent bolt tightening and quality analysis, achieving certain research results, mainly including the following:

[0004] Chinese invention patent application No. 202411229739.X discloses an intelligent identification method for abnormal assembly curves of fasteners. The method involves acquiring fastener assembly curve diagrams, preprocessing the images, preprocessing training diagrams of the fastener assembly curves, constructing a neural network model, labeling the training diagrams, and training the network. The trained neural network model is then used to acquire and identify fastener assembly curve diagrams. If an assembly abnormality is detected, an early warning notification is issued to relevant personnel. This method aims to solve the problem of effectively identifying abnormal assembly curves, improve the ability to identify abnormal assembly, further improve assembly efficiency, and reduce production costs. However, in practical applications, image processing technology requires a large number of experimental samples; otherwise, it cannot accurately identify curve anomalies.

[0005] Chinese invention patent application No. 202411562608.3 discloses a system and method for calculating and setting bolt tightening monitoring torque and angle. The system sets a first monitoring torque value based on the final tightening torque value, and a first monitoring angle value based on the effective engagement length of the bolt and the thread specification. A second monitoring torque value is set based on the final tightening torque value, and a second monitoring angle value is set based on the thread specification. Based on the preset monitoring torque and angle values, the tightening results are statistically analyzed to obtain corrected monitoring torque and angle values, and the bolt tightening condition is monitored based on these corrected values. However, in practical applications, only torque and angle are analyzed, which cannot fully describe and analyze the tightening process.

[0006] Chinese invention patent application No. 202510187902.9 discloses an online detection method and system for the external assembly process of a pipeline machine. The method involves constructing a tightening control model and initializing its parameters, adjusting the conduit and connector to their initial state and applying tightening torque, reading tightening process information in real time and plotting a tightening curve; real-time detection of the maximum tightening torque and maximum tightening angle; real-time calculation of the assembly result; and real-time reading of tightening process data. The tightening process data is input into the tightening control model, and control parameters and boundary parameters for the external assembly of the conduit machine are set simultaneously. However, in practical applications, parameters such as torque, angle, and curve are detected separately, failing to achieve intelligent tightening and control.

[0007] Chinese invention patent application No. 202411164450.4 discloses an intelligent tightening control device and method considering the stick-slip effect. This method involves calling up relevant tightening process information, process parameters, and production requirements based on a specific process. The process information analysis results are used to determine the tightening control method and its parameters, generating a control signal for the required tightening action. The tightening action begins upon execution of the control signal. Torque data generated during tightening is monitored and analyzed in real time. The average torque value is continuously calculated over short time intervals, forming a torque average value change curve. The magnitude of fluctuations in the torque average value change curve determines whether a stick-slip effect has occurred. Different tightening and feedback strategies are determined based on the presence or absence of the stick-slip effect. However, in practical applications, only the change in torque is analyzed, which does not achieve intelligent tightening and control.

[0008] Chinese invention patent application No. 202210527062.2 discloses a method for judging thread tightening quality based on curve similarity and clustering. It uses curve similarity to preprocess the displacement-tightening torque curve thread tightening quality data, and then uses a binary k-means clustering algorithm combined with the Spark distributed processing engine to extract feature points for each preprocessed category. For each category, the extracted feature points are connected to obtain the thread tightening quality feature curve for each category. Based on the well-defined category, real-time thread tightening quality data point judgment is performed. However, in practical applications, a large number of test samples are required. Curve types not included in the sample size cannot be identified, thus failing to achieve intelligent tightening and control. Summary of the Invention

[0009] To address the aforementioned problems, this invention proposes an intelligent bolt tightening system and an online method for analyzing tightening quality. This system enables intelligent positioning of the tightening device during the bolt tightening process. It features a simple structure, ease of implementation, and wide applicability.

[0010] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution:

[0011] In a first aspect, the present invention provides a smart bolt tightening system, comprising:

[0012] Bolt head retaining clamp, used to fix bolt heads;

[0013] The first connector has a through hole for the bolt body to pass through;

[0014] A tightening device used to tighten or loosen a nut on the bolt body at the end furthest from the bolt head;

[0015] The sliding guide rail is slidably connected to the tightening device;

[0016] The shooting unit is connected to the sliding guide rail;

[0017] A horizontal thrust unit is connected to the sliding guide rail and to the tightening device;

[0018] The upper and lower thrust units are connected to the horizontal thrust unit;

[0019] The control unit is connected to the shooting unit, the tightening device, the horizontal thrust unit, and the vertical thrust unit respectively. Based on the real-time position of the nut captured by the shooting unit, the control unit controls the horizontal thrust unit and the vertical thrust unit to adjust the position of the tightening device and control the working state of the tightening device.

[0020] In conjunction with the first aspect, optionally, the tightening device includes a tightening clamp and a tightening power unit;

[0021] The tightening clamp is used to hold the nut in place and tighten it.

[0022] The tightening power unit is fixedly connected to the tightening clamp and is used to drive the tightening clamp to rotate. It is also slidably connected to the sliding guide rail and can slide relative to the sliding guide rail.

[0023] In conjunction with the first aspect, optionally, the shooting unit captures the real-time position of the nut and sends it to the control unit. The control unit controls the upper and lower thrust units and the horizontal thrust units to adjust the position of the tightening clamp in the tightening device in real time based on the real-time position of the nut until the tightening clamp is stuck on the nut. At this time, the control unit controls the tightening power unit to start the tightening action.

[0024] In conjunction with the first aspect, optionally, the control unit simulates critical thresholds for torque, angle, and slope based on collected historical torque and historical angle data, wherein the slope is calculated using the following formula:

[0025] K n = (T n+1 -T n ) / (θ n+1 -θ n ),

[0026] In the formula, K n Let T be the slope at time n. n+1 Let T be the torque at time n+1. n Let θ be the torque at time n. n+1 Let θ be the angle at time n+1. n Let the angle be at time n;

[0027] During the tightening process, the tightening power unit uploads real-time torque and real-time angle to the control unit. The control unit calculates the real-time slope based on the real-time torque and real-time angle, and performs a failure judgment based on the critical thresholds of torque, angle, and slope, as well as the real-time torque, real-time angle, and real-time slope, according to preset criteria. The preset criteria include:

[0028] If the torque is acceptable but the angle is unacceptable, the slope is unacceptable because it exceeds the set threshold, which is a Class A failure.

[0029] If the torque and angle are both acceptable, but the slope is not, it is classified as a Class B failure.

[0030] If the torque is acceptable but the angle is unacceptable, the slope is unacceptable because it is less than the set threshold, which is a Class C failure.

[0031] In conjunction with the first aspect, optionally, when the control unit simultaneously identifies a Class A failure, a Class B failure, and a Class C failure, it controls the tightening device to stop tightening and loosens it in the reverse direction. After loosening, the camera unit collects the real-time position of the nut until the tightening device moves to a safe position and then controls the tightening device to stop loosening in the reverse direction.

[0032] In conjunction with the first aspect, optionally, the critical threshold range of the torque is 415±10 Nm; the critical threshold range of the angle is 17.2°-24.2°; and the critical threshold range of the slope k is 7.36-12.95 Nm / °.

[0033] In conjunction with the first aspect, optionally, the type A failure indicates jamming, the type B failure indicates yielding, and the type C failure indicates a missing gasket.

[0034] In conjunction with the first aspect, optionally, the horizontal thrust unit includes a second connector, a first fixing device, a horizontal thrust cylinder, a horizontal connecting block, and an elastic element;

[0035] The first fixing device is fixedly connected to the second connecting member;

[0036] The cylinder body of the horizontal thrust cylinder is fixedly connected to the first fixing device;

[0037] The second connector has a groove at its end near the first connector;

[0038] The horizontal connecting block and the elastic element are both disposed within the sliding groove;

[0039] The horizontal connecting block is connected to the tightening device;

[0040] The piston rod of the horizontal thrust cylinder contacts the elastic element. When the piston rod of the horizontal thrust cylinder extends or retracts, it drives the elastic element and the horizontal connecting block to move the tightening device left and right in the horizontal direction.

[0041] In conjunction with the first aspect, optionally, the upper and lower thrust unit includes a third connecting member, upper and lower thrust cylinders, a second fixing device, and upper and lower connecting blocks;

[0042] The second fixing device is fixedly connected to the third connecting member;

[0043] The cylinder body of the upper and lower thrust cylinders is fixedly connected to the second fixing device;

[0044] The piston rod of the upper and lower thrust cylinders is connected to the upper and lower connecting blocks, which are connected to the horizontal thrust unit. When the piston rod of the upper and lower thrust cylinders extends or retracts, it drives the upper and lower connecting blocks to move the horizontal thrust unit and the tightening device vertically up and down.

[0045] In a second aspect, the present invention provides an online method for analyzing the tightening quality of a bolt intelligent tightening system applicable to any one of the first aspects, comprising:

[0046] Pass the bolt body through the through hole on the first connector;

[0047] Use a bolt head fixing clamp to fix the bolt head;

[0048] The real-time position of the nut is captured by the camera unit and sent to the control unit.

[0049] The control unit uses the real-time position of the nut captured by the camera unit to control the horizontal thrust unit and the vertical thrust unit to adjust the position of the tightening device so that the tightening device is locked on the nut, and then controls the tightening device to start the tightening action.

[0050] During the tightening process, the tightening device uploads the real-time torque and real-time angle to the control unit, so that the control unit can calculate the real-time slope based on the real-time torque and real-time angle, and perform failure judgment according to the critical thresholds of torque, angle, and slope, as well as the real-time torque, real-time angle, and real-time slope, and complete the online analysis of tightening quality.

[0051] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0052] This invention proposes an intelligent bolt tightening system and an online method for analyzing tightening quality. It can realize intelligent positioning of the tightening device during the bolt tightening process. It has a simple structure, is easy to implement, and has a wide range of applications. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0054] Figure 1 This is a schematic diagram of the structure of an intelligent bolt tightening system according to an embodiment of the present invention;

[0055] Figure 2 This is a schematic diagram of the normal tightening curve analysis according to an embodiment of the present invention;

[0056] Figure 3 This is a schematic diagram of abnormal tightening curve analysis according to an embodiment of the present invention;

[0057] 1- Bolt head fixing clamp, 2- First connecting piece, 3.1- Bolt, 3.2- Nut, 4- Tightening device, 4.1- Tightening clamp, 4.2- Tightening power unit, 5- Sliding guide rail, 6- Imaging unit, 7- Horizontal thrust unit, 7.1- Horizontal connecting block, 7.2 Elastic element, 7.3- Piston rod of horizontal thrust cylinder, 7.4- Horizontal thrust cylinder, 7.5- First fixing device, 8- Upper and lower thrust unit, 8.1- Upper and lower thrust cylinder, 8.2- Second fixing device, 8.3- Piston rod of upper and lower thrust cylinder, 8.4- Upper and lower connecting block, 9- Control unit. Detailed Implementation

[0058] The technical solutions of 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. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. 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.

[0059] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may include different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0060] In the description of this invention, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0061] In the description of this invention, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0062] The application principle of the present invention will be described in detail below with reference to the accompanying drawings.

[0063] Example 1

[0064] This invention provides a smart bolt tightening system, such as... Figure 1 As shown, it includes:

[0065] Bolt head fixing clamp 1, used to fix the bolt head;

[0066] The first connecting member 2 is provided with a through hole for the bolt body to pass through; the bolt head and the bolt body together constitute the bolt 3.1;

[0067] Tightening device 4 is used to tighten and loosen the nut 3.2 to the end of the bolt body away from the bolt head;

[0068] The sliding guide rail 5 is slidably connected to the tightening device 4;

[0069] The shooting unit 6 is connected to the sliding guide rail 5. In specific implementation, the shooting unit 6 and the sliding guide rail 5 can be fixedly connected or detachably connected.

[0070] The horizontal thrust unit 7 is connected to the sliding guide rail 5 and the tightening device 4;

[0071] The vertical thrust unit 8 is connected to the horizontal thrust unit 7;

[0072] The control unit 9 is connected to the shooting unit 6, the tightening device 4, the horizontal thrust unit 7, and the vertical thrust unit 8 respectively. Based on the real-time position of the nut 3.2 captured by the shooting unit 6, the control unit 9 controls the horizontal thrust unit 7 and the vertical thrust unit 8 to adjust the position of the tightening device 4 and control the working state of the tightening device 4.

[0073] Based on the above scheme, the tightening device 4 can achieve intelligent positioning during the bolt tightening process. It has a simple structure, is easy to implement, and has a wide range of applications. In specific implementation, the structure of the bolt head fixing clamp 1 can be adaptively selected according to the cross-section of the bolt head, as long as it can fix the bolt head and ensure that the bolt head does not move relative to the bolt head fixing clamp 1. The first connecting member 2 can be an integral structure or multiple separate structures connected according to a predetermined connection relationship to form an integral structure. The number of bolt head fixing clamps 1 is determined by the number of bolts. When multiple bolts need to be tightened simultaneously, multiple bolt head fixing clamps 1 can be selected.

[0074] In one specific embodiment of the present invention, the tightening device 4 includes a tightening clamp 4.1 and a tightening power unit 4.2;

[0075] The tightening clamp 4.1 is used to hold the nut 3.2 in place and tighten the nut 3.2.

[0076] The tightening power unit 4.2 is fixedly connected to the tightening clamp 4.1 and is used to drive the tightening clamp 4.1 to rotate. It is also slidably connected to the sliding guide rail 5 and can slide relative to the sliding guide rail 5.

[0077] In the above scheme, when the tightening device 4 moves to the predetermined position and the tightening clamp 4.1 is engaged with the nut 3.2, the tightening power unit 4.2 drives the tightening clamp 4.1 to rotate, thereby rotating the nut 3.2 on the bolt body to complete the tightening or loosening action. In specific implementation, the structure of the tightening clamp 4.1 can be adapted according to the cross-section of the nut 3.2, as long as it can fix the nut 3.2 and ensure that the nut 3.2 does not move relative to the tightening clamp 4.1. The tightening power unit 4.2 includes a housing and a power source disposed within the housing. The housing is slidably connected to the sliding guide rail 5, and the power source is connected to the tightening clamp 4.1, thereby enabling the tightening power unit 4.2 to drive the tightening clamp 4.1 to rotate and to slide relative to the sliding guide rail 5. In specific implementation, the sliding guide rail 5 can be implemented using a pipe or track with a smooth inner wall.

[0078] In one specific embodiment of the present invention, the shooting unit 6 captures the real-time position of the nut 3.2 and sends it to the control unit 9. The control unit 9 controls the upper and lower thrust units 8 and the horizontal thrust units 7 to adjust the position of the tightening clamp 4.1 in the tightening device 4 in real time based on the real-time position of the nut 3.2 until the tightening clamp 4.1 is stuck on the nut 3.2. At this time, the control unit 9 controls the tightening power unit 4.2 to start the tightening action.

[0079] The above solution enables intelligent positioning and guidance of the tightening device 4. In specific implementation, the shooting unit 6 can be a 3D camera or other devices capable of image capture.

[0080] In one specific embodiment of the present invention, the control unit 9 simulates critical thresholds for torque, angle, and slope based on collected historical torque and historical angle, wherein the slope is calculated using the following formula:

[0081] K n = (T n+1 -T n ) / (θ n+1 -θ n ),

[0082] In the formula, K n Let T be the slope at time n. n+1 Let T be the torque at time n+1. n Let θ be the torque at time n. n+1 Let θ be the angle at time n+1. n Let n be the angle at time n. In the specific implementation process, the starting point of the tightening data (including torque and angle) is calculated from 30%-50% of the final torque (in this example, the data is processed at 50%) to obtain the critical thresholds of torque, angle and slope.

[0083] During the tightening process, the tightening power unit 4.2 uploads the real-time torque and real-time angle to the control unit 9. The control unit 9 calculates the real-time slope based on the real-time torque and real-time angle, and performs a failure judgment according to preset criteria based on the critical thresholds of torque (T), angle (θ), and slope (K), as well as the real-time torque, real-time angle, and real-time slope. Figure 3 As shown, the preset criteria include:

[0084] If the torque is acceptable but the angle is unacceptable, the slope is unacceptable because it exceeds the set threshold (i.e., the slope is too high and therefore unacceptable), which is a Class A failure.

[0085] If the torque and angle are both acceptable, but the slope is not, it is classified as a Class B failure.

[0086] If the torque is acceptable but the angle is unacceptable, the slope is unacceptable because it is less than the set threshold (i.e., the slope is too low and therefore unacceptable), which is a Class C failure.

[0087] The above solution enables online intelligent monitoring of key tightening parameters (torque, angle, slope, etc.) during the automatic tightening process, and completes online analysis of tightening quality.

[0088] In one specific embodiment of the present invention, when the control unit 9 simultaneously identifies a Class A failure, a Class B failure, and a Class C failure, it controls the tightening device 4 to stop tightening and loosens it in the reverse direction. After loosening, the imaging unit 6 collects the real-time position of the nut 3.2 until the tightening device 4 moves to a safe position and the control unit 4 stops loosening in the reverse direction.

[0089] Based on the above scheme, when an anomaly occurs during online analysis, the tightening device 4 can be controlled to stop tightening and be reversed to loosen (i.e., disassembled). The tightening device 4 can also be controlled to move to a safe position based on the real-time position of the nut 3.2 collected by the imaging unit 6.

[0090] In one specific embodiment of the present invention, such as Figure 2 As shown, the critical threshold range of the torque is 415±10 Nm; the critical threshold range of the angle is 17.2°-24.2°; and the critical threshold range of the slope k is 7.36-12.95 Nm / °.

[0091] In one specific embodiment of the present invention, the Type A failure indicates jamming, the Type B failure indicates yielding, and the Type C failure indicates missing gasket.

[0092] In one specific embodiment of the present invention, such as Figure 1 As shown, the horizontal thrust unit 7 includes a second connector, a first fixing device 7.5, a horizontal thrust cylinder 7.4, a horizontal connecting block 7.1, and an elastic element 7.2;

[0093] The first fixing device 7.5 is fixedly connected to the second connecting member;

[0094] The cylinder body of the horizontal thrust cylinder 7.4 is fixedly connected to the first fixing device 7.5;

[0095] The second connector has a groove at its end near the first connector 2;

[0096] Both the horizontal connecting block 7.1 and the elastic element 7.2 are located within the slide groove; in specific implementation, the elastic element 7.2 can be a spring or other elastic components.

[0097] The horizontal connecting block 7.1 is connected to the tightening device 4;

[0098] The piston rod 7.3 of the horizontal thrust cylinder contacts the elastic element 7.2. When the piston rod 7.3 of the horizontal thrust cylinder extends or retracts, it drives the elastic element 7.2 and the horizontal connecting block 7.1 to move the tightening device 4 left and right in the horizontal direction.

[0099] In the above scheme, when the horizontal position of the tightening device 4 needs to be adjusted, the control unit 9 can control the piston rod 7.3 of the horizontal thrust cylinder to extend or retract as needed. When the tightening device 4 needs to be adjusted to the left, the control unit 9 controls the piston rod 7.3 of the horizontal thrust cylinder to extend, compressing the elastic element 7.2, thereby enabling the tightening device 4 to move to the left using the horizontal connecting block 7.1. When the tightening device 4 needs to be adjusted to the right, the control unit 9 controls the piston rod 7.3 of the horizontal thrust cylinder to retract, and the elastic element 7.2 slowly resets, thereby enabling the tightening device 4 to move to the right using the horizontal connecting block 7.1. In specific applications, the number of horizontal thrust units 7 can be set multiple times according to actual needs, with each horizontal thrust unit 7 spaced apart to achieve intelligent tightening of multiple bolts.

[0100] In one specific embodiment of the present invention, such as Figure 1 As shown, the upper and lower thrust unit 8 includes a third connecting member, an upper and lower thrust cylinder 8.1, a second fixing device 8.2, and an upper and lower connecting block 8.4;

[0101] The second fixing device 8.2 is fixedly connected to the third connecting member;

[0102] The cylinder body of the upper and lower thrust cylinder 8.1 is fixedly connected to the second fixing device 8.2;

[0103] The piston rod 8.3 of the upper and lower thrust cylinders is connected to the upper and lower connecting blocks 8.4, which are connected to the horizontal thrust unit 7. When the piston rod 8.3 of the upper and lower thrust cylinders extends or retracts, it drives the upper and lower connecting blocks 8.4 to move the horizontal thrust unit 7 and the tightening device 4 vertically up and down.

[0104] In the above scheme, when the vertical position of the tightening device 4 needs to be adjusted, the control unit 9 can control the piston rod 8.3 of the upper and lower thrust cylinders to extend or retract as needed. When the tightening device 4 needs to be adjusted downwards, the control unit 9 controls the piston rod 8.3 of the upper and lower thrust cylinders to extend, thereby enabling the tightening device 4 to move downwards using the upper and lower connecting blocks 8.4. When the tightening device 4 needs to be adjusted upwards, the control unit 9 controls the piston rod 8.3 of the upper and lower thrust cylinders to retract, thereby enabling the tightening device 4 to move upwards using the upper and lower connecting blocks 8.4. In specific applications, the number of upper and lower thrust units 8 can be set multiple times according to actual needs, with each upper and lower thrust unit 8 spaced apart to achieve intelligent tightening of multiple bolts.

[0105] Example 2

[0106] This invention provides an online method for analyzing the tightening quality of a bolt intelligent tightening system applicable to any one of Embodiment 1, comprising:

[0107] Pass the bolt body through the through hole on the first connector 2;

[0108] Use bolt head fixing clamp 1 to fix the bolt head;

[0109] The real-time position of nut 3.2 is captured by the imaging unit 6 and sent to the control unit 9.

[0110] Using the real-time position of nut 3.2 captured by the shooting unit 6, the control unit 9 controls the horizontal thrust unit 7 and the vertical thrust unit 8 to adjust the position of the tightening device 4 so that the tightening device 4 is locked on nut 3.2, and then controls the tightening device 4 to start the tightening action.

[0111] During the tightening process, the tightening device 4 uploads the real-time torque and real-time angle to the control unit 9, so that the control unit 9 can calculate the real-time slope based on the real-time torque and real-time angle, and perform failure judgment according to the preset criteria based on the critical thresholds of torque, angle, and slope, thereby completing the online analysis of tightening quality.

[0112] This invention enables intelligent positioning of the tightening device 4 during the bolt tightening process. Simultaneously, it allows for the setting and analysis of quality thresholds based on multiple parameters (torque, angle, and slope) during the tightening process, thereby achieving online evaluation of tightening quality and providing better guidance for improving bolt connection processes and enhancing quality.

[0113] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only used to facilitate the description of the present invention and to simplify the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of the present invention.

[0114] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A smart bolt tightening system, characterized in that, include: Bolt head retaining clamp, used to fix bolt heads; The first connector has a through hole for the bolt body to pass through; A tightening device used to tighten or loosen a nut on the bolt body at the end furthest from the bolt head; The sliding guide rail is slidably connected to the tightening device; The shooting unit is connected to the sliding guide rail; A horizontal thrust unit is connected to the sliding guide rail and to the tightening device; The upper and lower thrust units are connected to the horizontal thrust unit; The control unit is connected to the shooting unit, the tightening device, the horizontal thrust unit and the vertical thrust unit respectively. Based on the real-time position of the nut captured by the shooting unit, the control unit controls the horizontal thrust unit and the vertical thrust unit to adjust the position of the tightening device and control the working state of the tightening device. The tightening device includes a tightening clamp and a tightening power unit; The tightening clamp is used to hold the nut in place and tighten it. The tightening power unit is fixedly connected to the tightening fixture and is used to drive the tightening fixture to rotate. It is also slidably connected to the sliding guide rail and can slide relative to the sliding guide rail. Based on collected historical torque and angle data, the control unit simulates critical thresholds for torque, angle, and slope. The slope is calculated using the following formula: K n =(T n+1 -T n ) / (θ n+1 -θ n ) In the formula, K n Let T be the slope at time n. n+1 Let T be the torque at time n+1. n Let θ be the torque at time n. n+1 Let θ be the angle at time n+1. n Let the angle be at time n; During the tightening process, the tightening power unit uploads real-time torque and real-time angle to the control unit. The control unit calculates the real-time slope based on the real-time torque and real-time angle, and performs a failure judgment based on the critical thresholds of torque, angle, and slope, as well as the real-time torque, real-time angle, and real-time slope, according to preset criteria. The preset criteria include: If the torque is acceptable but the angle is unacceptable, the slope is unacceptable because it exceeds the set threshold, which is a Class A failure. If the torque and angle are both acceptable, but the slope is not, it is classified as a Class B failure. If the torque is acceptable but the angle is unacceptable, the slope is unacceptable because it is less than the set threshold, which is a Class C failure.

2. The intelligent bolt tightening system according to claim 1, characterized in that: The camera unit captures the real-time position of the nut and sends it to the control unit. Based on the real-time position of the nut, the control unit controls the upper and lower thrust units and the horizontal thrust units to adjust the position of the tightening clamp in the tightening device in real time until the tightening clamp is stuck on the nut. At this time, the control unit controls the tightening power unit to start the tightening action.

3. The intelligent bolt tightening system according to claim 1, characterized in that: When the control unit simultaneously detects Class A, Class B, and Class C failures, it controls the tightening device to stop tightening and loosens it in the reverse direction. After loosening, the camera unit collects the real-time position of the nut until the tightening device moves to a safe position, at which point the control unit stops the reverse loosening.

4. The intelligent bolt tightening system according to claim 1, characterized in that: The critical threshold range of the torque is 415±10 Nm; the critical threshold range of the angle is 17.2°-24.2°; and the critical threshold range of the slope k is 7.36-12.95 Nm / °.

5. The intelligent bolt tightening system according to claim 1, characterized in that: Type A failures indicate jamming, Type B failures indicate yielding, and Type C failures indicate missing gaskets.

6. The intelligent bolt tightening system according to claim 1, characterized in that: The horizontal thrust unit includes a second connector, a first fixing device, a horizontal thrust cylinder, a horizontal connecting block, and an elastic element; The first fixing device is fixedly connected to the second connecting member; The cylinder body of the horizontal thrust cylinder is fixedly connected to the first fixing device; The second connector has a groove at its end near the first connector; The horizontal connecting block and the elastic element are both disposed within the sliding groove; The horizontal connecting block is connected to the tightening device; The piston rod of the horizontal thrust cylinder contacts the elastic element. When the piston rod of the horizontal thrust cylinder extends or retracts, it drives the elastic element and the horizontal connecting block to move the tightening device left and right in the horizontal direction.

7. The intelligent bolt tightening system according to claim 1, characterized in that: The upper and lower thrust units include a third connector, upper and lower thrust cylinders, a second fixing device, and upper and lower connecting blocks; The second fixing device is fixedly connected to the third connecting member; The cylinder body of the upper and lower thrust cylinders is fixedly connected to the second fixing device; The piston rod of the upper and lower thrust cylinders is connected to the upper and lower connecting blocks, which are connected to the horizontal thrust unit. When the piston rod of the upper and lower thrust cylinders extends or retracts, it drives the upper and lower connecting blocks to move the horizontal thrust unit and the tightening device vertically up and down.

8. A method for online analysis of tightening quality of a bolt intelligent tightening system applicable to any one of claims 1-7, characterized in that, include: Pass the bolt body through the through hole on the first connector; Use a bolt head fixing clamp to fix the bolt head; The real-time position of the nut is captured by the camera unit and sent to the control unit. The control unit uses the real-time position of the nut captured by the camera unit to control the horizontal thrust unit and the vertical thrust unit to adjust the position of the tightening device so that the tightening device is locked on the nut, and then controls the tightening device to start the tightening action. During the tightening process, the tightening device uploads the real-time torque and real-time angle to the control unit, so that the control unit can calculate the real-time slope based on the real-time torque and real-time angle, and perform failure judgment according to the critical thresholds of torque, angle, and slope, as well as the real-time torque, real-time angle, and real-time slope, and complete the online analysis of tightening quality.

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