Screwdriver with torque wrench and torque control method based on tightening characteristics

Abstract

The invention relates to the technical field of intelligent tools, and particularly provides a screwdriver with a torque wrench and a torque control method based on tightening characteristics, and the method comprises the steps: generating a tightening characteristic library of a target screw in response to a resistance change, collecting angle data and torque data of a screw head when the target screw is tightened, constructing a torque-angle curve in the tightening feature library; key features in the torque-angle curve are extracted, and corresponding screw states are matched in a screw state library; and preset pre-tightening parameters corresponding to the screw state are inquired, the pre-tightening parameters are integrated, and a self-adaptive final torque adjusting strategy is output. And dynamically generating and outputting a final torque adjustment strategy according to real-time data collected in the actual tightening process and in combination with a preset screw state library. The screw state can be adapted, the final torque adjusting strategy is adjusted in real time, and it is ensured that the optimal and safe fastening effect is achieved.

Description

Technical Field

[0001] The present application relates to the technical field of intelligent tools, and in particular to a screwdriver with a torque wrench and a torque control method based on tightening characteristics. Background Art

[0002] An electric screwdriver is a tool used to tighten screws. It is used in the fields of household tools and industrial robots. After pre-tightening with an electric screwdriver, the screws need to be tightened with a torque wrench to measure whether the screws are over-tightened or under-tightened. In related technologies, the torque wrench and the electric screwdriver are integrated on the same device to improve the efficiency of the pre-tightening and final tightening operations of the screws.

[0003] However, when using an existing screwdriver with a torque wrench, the two tools are independent of each other, and data cannot be communicated between the screwdriver and the torque wrench. Tightening relies on the worker's experience, and the degree of automation is low. Summary of the Invention

[0004] The primary purpose of the present application is to solve at least one of the above problems and provide an electric screwdriver with a torque wrench, comprising:

[0005] Equipment housing;

[0006] A tightening assembly, the tightening assembly being disposed in the device housing, the electric screw head comprising a first drive unit, a ratchet driver, and a screw head connected in sequence;

[0007] A torque assembly, the torque assembly comprising a second drive unit, a planetary gear reducer, and a torque output shaft connected in sequence;

[0008] A sensing assembly, the sensing assembly being sleeved on the screw head and the torque output shaft, the sensing assembly comprising a torque sensor and an angle sensor;

[0009] A control component is disposed in the device housing and is electrically connected to the first drive unit, the second drive unit, and the sensor component.

[0010] Optionally, the device housing includes a tightening part and a torque part perpendicular to each other, and the interiors of the tightening part and the torque part respectively form inner cavities for accommodating the tightening assembly and the torque assembly, and the tightening assembly and the torque assembly are respectively arranged in the tightening part and the torque part.

[0011] Optionally, an ultrasonic transducer and a receiver are also included, and the ultrasonic transducer and the receiver are both arranged in the device housing and located on the rear side of the tightening assembly.

[0012] Optionally, the control component includes a main control circuit board and a wireless transmission unit, and the wireless transmission unit is electrically connected to the main control circuit board.

[0013] In another aspect, a torque wrench control method based on tightening characteristics is provided to meet one of the objectives of the present application. The torque wrench control method comprises the following steps:

[0014] In response to the resistance change, a tightening feature library of the target screw is generated, angle data and torque data of the screw head when tightening the target screw are collected, and a torque-angle curve is constructed in the tightening feature library;

[0015] Extracting key features from the torque-angle curve and matching corresponding screw states in a screw state library;

[0016] The preset pre-tightening parameters corresponding to the screw state are queried, the pre-tightening parameters are integrated and an adaptive final torque adjustment strategy is output.

[0017] Optionally, extracting key features from the torque-angle curve comprises the following steps:

[0018] Traversing the slopes of the torque-angle curve, calculating an average value of the slopes and determining whether the average value is greater than a preset gentle slope, if so, outputting a rough state, otherwise outputting a standard state;

[0019] Obtaining the number of times the slope is greater than a preset fluctuation slope, and outputting the screw state as a defective state if the number is greater than a preset fluctuation value, otherwise outputting the screw state as a standard state;

[0020] Determine whether the slope ratio before and after the slope change point is greater than the preset value. If so, output the screw state as a sudden change state, otherwise output the standard state.

[0021] The querying of the preset pre-tightening parameters corresponding to the screw state includes the following steps:

[0022] When the screw state is a standard state, the pre-tightening parameters are set to a high initial speed and a high torque threshold, and the operation is continued until the torque meets the torque threshold;

[0023] When the screw state is rough, the pre-tightening parameters are set to a low initial speed and a low torque threshold, and the screw is continuously operated until it is linearly decelerated when approaching the torque threshold.

[0024] When the screw state is a defective state; the pre-tightening parameters are set to a low initial speed and a low torque threshold, and the operation is intermittent;

[0025] When the screw state is a sudden change state, the pre-tightening parameters are set to a low initial speed and a low torque threshold, and the screw is continuously operated until the change point, at which time the speed is temporarily reduced.

[0026] Optionally, after constructing the torque-angle curve in the tightening feature library, the following steps are included:

[0027] Identify the linear region of the torque-angle curve, calculate the slope of this region and calculate the material hardness;

[0028] The yield point where the slope changes from linear to nonlinear is identified, the torque value and angle value corresponding to the yield point are recorded, and the hardness of the material is determined based on the position of the yield point in the torque-angle curve.

[0029] Optionally, generating a tightening feature library of a target screw comprises the following steps:

[0030] A tightening strategy is output based on the tightening feature library of the first target screw, a feature set including multiple tightening feature libraries of the same type is constructed, key features in the feature set are comprehensively analyzed, and a torque adjustment strategy is output.

[0031] Optionally, the output adaptive final torque adjustment strategy includes the following steps:

[0032] Acquire the reflected echo signal of the ultrasonic wave;

[0033] Extract the callback features in the reflected echo signal and compare them with the preset defect feature library to identify the defect information;

[0034] The final torque adjustment strategy is adjusted according to the defect information and a prompt signal is output.

[0035] The technical solution of this application has many advantages, including but not limited to the following:

[0036] This application first integrates an electric screwdriver and a torque wrench into a single tool. When performing screw tightening operations, torque can be applied directly through the torque wrench after the screw is tightened. There is no need to look for the torque wrench, and the torque wrench is not easy to lose, thereby achieving convenient pre-tightening of screws and application of precise torque.

[0037] Secondly, based on real-time data collected during the actual tightening process and combined with a pre-set screw status library, a final torque adjustment strategy is dynamically generated and output. This system adapts to the screw's state and adjusts the final torque adjustment strategy in real time to ensure an optimal and safe tightening result. This avoids problems such as slippage and breakage caused by excessive preset torque, or loosening caused by too low a preset torque, significantly improving tightening accuracy and consistency when tightening multiple screws. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a three-dimensional structural diagram of the electric screwdriver with torque wrench of the present application;

[0039] Figure 2 This is a diagram of the internal structure of the electric screwdriver with torque wrench of the present application;

[0040] Figure 3 is a flow chart of an embodiment of a torque wrench control method based on tightening features of the present application;

[0041] Description of reference numerals:

[0042] 10. Equipment housing; 20. Tightening assembly; 21. First drive unit; 22. Ratchet transmission; 23. Screw head; 30. Torque assembly; 31. Second drive unit; 32. Planetary gear reducer; 33. Torque output shaft; 40. Sensor assembly; 50. Control assembly; 60. Ultrasonic transducer; 61. Receiver. DETAILED DESCRIPTION

[0043] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0044] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "multiple" means two or more.

[0045] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0046] The technical solution of the present application is applicable to the field of automated control, and is particularly applicable to screwdriver tools for household and industrial robots. In this context, the technical solution of the present application can be applied to an electric screwdriver with a torque wrench, such as Figure 1 and Figure 2 As shown, Figure 1 An electric screwdriver with a torque wrench is proposed, comprising a device housing 10, a tightening assembly 20, a torque assembly 30, a sensing assembly 40 and a control assembly 50; the tightening assembly 20 is arranged in the device housing 10, and the electric screw head 23 includes a first drive unit 21, a ratchet transmission 22 and a screw head 23 connected in sequence; the torque assembly 30 includes a second drive unit 31, a planetary gear reducer 32 and a torque output shaft 33 connected in sequence; the sensing assembly 40 is sleeved on the screw head 23 and the torque output shaft, and the sensing assembly 40 includes a torque sensor and an angle sensor; the control assembly 50 is arranged in the device housing 10 and is electrically connected to the first drive unit 21, the second drive unit 31 and the sensing assembly 40.

[0047] Among them, the tightening assembly 20 and the torque assembly 30 can be independently arranged in the device housing 10, and the specific structures of the ratchet transmission 22 and the planetary gear reducer 32 can adopt the electric screwdriver tool and electric torque wrench tool in the prior art. In this embodiment, the first drive unit 21 and the second drive unit 31 are both driven by motors. The tightening assembly 20 and the torque assembly 30 are both arranged in the L-shaped device housing 10 and extend from the two ends of the device housing 10. When using the tightening assembly 20 or the torque assembly 30, the other end can be used as a gripping handle.

[0048] Among them, the screw head 23 and the torque output shaft 33 are both equipped with torque sensors and angle sensors, which can obtain the torque parameters and angle parameters of the screw head 23 and the torque output shaft 33 in real time, so that the control component 50 can accurately adjust the torque component 30 according to the parameters, realize dynamic control, and effectively improve the intelligence of the equipment.

[0049] Among them, such as Figure 2As shown, the device housing 10 includes a tightening portion and a torque portion perpendicular to each other, and the interiors of the tightening portion and the torque portion respectively form inner cavities for accommodating the tightening assembly 20 and the torque assembly 30, and the tightening assembly 20 and the torque assembly 30 are respectively arranged in the tightening portion and the torque portion.

[0050] In some embodiments, an ultrasonic transducer 60 and a receiver 61 are further included, both of which are disposed in the device housing 10 and located on the rear side of the tightening assembly 20. The ultrasonic transducer 60 is used to transmit ultrasonic waves in a specified direction, and the receiver 61 receives the reflected echo of the ultrasonic waves on the target screw, performing feature analysis to identify screw defects.

[0051] Among them, such as Figure 1 As shown, a detection cylinder is provided on the rear side of the L-shaped device housing 10 in the coaxial direction with the tightening component 20 or the torque component 30. The ultrasonic transducer 60 and the receiver 61 are provided in the detection cylinder. When performing detection, the detection cylinder is put on the screw head 23 to excite the ultrasonic transducer 60 to detect the target screw, and the ultrasonic echo signal is received by the receiver 61, and the signal is fed back to the control component 50 for analysis.

[0052] In some embodiments, the control component 50 includes a main control circuit board and a wireless transmission unit. The wireless transmission unit is electrically connected to the main control circuit board. Various parameters obtained during the use of the device are uploaded to a computing device or the cloud for analysis through the wireless transmission unit, thereby realizing a distributed architecture and avoiding the problem of low analysis efficiency caused by insufficient computing power of the main control circuit board.

[0053] The wireless transmission unit may be mounted on the main control circuit board by welding, or may be connected to the main control circuit board by wire.

[0054] Among them, computing devices can be computers, mobile phones, servers and other intelligent terminals.

[0055] This application first integrates an electric screwdriver and a torque wrench into a single tool. When performing screw tightening operations, torque can be applied directly through the torque wrench after the screw is tightened. There is no need to look for the torque wrench, and the torque wrench is not easy to lose, thereby achieving convenient pre-tightening of screws and application of precise torque.

[0056] The following describes in detail the technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems with specific embodiments.

[0057] The following specific embodiments can be combined with each other, and the same or similar concepts or processes in some embodiments will not be described in detail. The following will describe the embodiments of the present application in conjunction with the accompanying drawings.

[0058] like Figure 3 As shown, the present application also discloses a torque wrench control method based on tightening characteristics, the torque wrench control method comprising the following steps:

[0059] 101. In response to the resistance change, generate a tightening feature library of the target screw, collect angle data and torque data of the screw head 23 when tightening the target screw, and construct a torque-angle curve in the tightening feature library;

[0060] The angle data and torque data can be collected by the angle sensor and torque sensor provided in the screwdriver with torque wrench, and the main target device for collection is the screw head 23 in the tightening component 20, or the torque output shaft 33 in the torque component 30.

[0061] Specifically, when the tool is inserted into the screw and started, since the rotation of the screw head 23 is blocked, it is judged that it has entered the tightening working state, a tightening feature library of the target screw is generated and relevant data is collected. When the equipment stops running for a preset time, it is judged that the working state is terminated, and the angle data and torque data are saved in the tightening feature library.

[0062] The torque-angle curve plots the tightening torque versus rotation angle, with the horizontal axis representing the rotation angle and the vertical axis representing the applied torque. By analyzing the morphological characteristics of the torque-angle curve, the tightening quality of screw connections can be accurately assessed and improved.

[0063] Specifically in this embodiment, after constructing the torque-angle curve in the tightening feature library, the screw material is also analyzed. First, the linear region of the torque-angle curve is identified, the slope of the region is calculated, and the material hardness is calculated; secondly, the yield point where the slope changes from linear to nonlinear is identified, the torque value and angle value corresponding to the yield point are recorded, and the material hardness is determined based on the position of the yield point in the torque-angle curve.

[0064] The linear region refers to the area where the torque-angle curve exhibits a linear development trend. This region corresponds to the elastic deformation phase of the bolt material. At this stage, the bolt's elongation is proportional to the applied torque. The mechanical behavior in this phase is predictable and reversible, making it an ideal range for analyzing preload forces. Selecting the linear region improves material analysis accuracy and avoids nonlinear interference during the preload phase. A higher slope in this region indicates a harder screw, requiring a higher torque to achieve the same rotation angle.

[0065] Among them, the yield point is a key feature, which marks the critical state where the screw material enters plastic deformation from elastic deformation. High-hardness materials usually have high yield strength. Screws with high hardness require greater torque to reach the yield point, so the yield point position of the torque-angle curve is further to the right.

[0066] The hardness of the target screw can be roughly estimated based on the slope and yield point, providing data reference for the strategy of applying torque by the torque component 30. Specifically, when the screw is harder, the initial rotation speed can be increased and the target torque can be further increased.

[0067] It can be understood that the relationship between the hardness of the screw and the initial speed can be obtained through a preset calculation formula, or several stepped initial speeds can be pre-set to correspond to different hardness ranges. When the hardness of the screw falls into the corresponding range, the corresponding initial speed is output. Among them, the initial speed can be roughly divided into high speed, medium speed and low speed, and can be further divided into high speed, medium-high speed, medium speed and low speed. The hardness range interval corresponding to each initial speed can be the same or different settings. Those skilled in the art can further set it in layers according to actual needs.

[0068] In some embodiments, the analysis accuracy can also be improved by constructing a data set containing tightening feature libraries of multiple screws in the same position. When constructing the tightening feature library of a single target screw, the tightening strategy is first output based on the tightening feature library of the first target screw, and a feature set containing multiple tightening feature libraries of the same type is constructed. The key features in the feature set are comprehensively analyzed and the torque adjustment strategy is output.

[0069] Among them, the device can enter the multi-screw tightening mode by pressing the button on the tightening tool or receiving the control signal of the smart terminal, and then the first target screw is pre-tightened and a tightening feature library is constructed. The tightening feature library also includes multiple key features. In the comprehensive analysis, the key features of multiple tightening feature libraries can be compared, and the key features with large differences can be regarded as abnormal features. When the ratio of the number of abnormal features to the total number of key features is less than a preset value, the abnormal feature is eliminated from the analysis process to avoid errors. When the ratio of the number of abnormal features to the total number of key features is greater than or equal to the preset value, the average value of the key features is taken for analysis.

[0070] Among them, multiple screws at the same position refer to multiple corresponding screws set on the parts to be connected. Usually, the connection structure and reinforcement structure of this type of screws are the same, and the same torque needs to be applied.

[0071] In some embodiments, ultrasonic defect detection can also be performed on the screws using an ultrasonic transducer installed on the device. When outputting the final torque adjustment strategy, if a large sudden change in the torque-angle curve of the target screw is detected during the detection, an alarm message is issued, prompting the use of the ultrasonic transducer 60 to further inspect the bolt. During the detection, the ultrasonic reflected echo signal is first obtained; the callback feature in the reflected echo signal is then extracted and compared with a preset defect feature library to identify the defect information; finally, the final torque adjustment strategy is adjusted based on the defect information, and a prompt signal is output. Screws are generally cylindrical. Guided waves propagating along the axial direction of the cylinder will form reflections when encountering defects. Therefore, by analyzing the reflected echo signal, the location and type of defects in the target screw can be identified.

[0072] Machine learning algorithms can be used to analyze echo characteristics such as depth, amplitude, and shape to identify screw defect types, including but not limited to cracks, damage, spalling, deformation, pores, or inclusions. If minor defects are detected, the final torque adjustment strategy will slightly reduce the target torque or enter a stricter monitoring mode, stopping immediately if the torque is abnormal.

[0073] Specifically, before testing, multiple experiments are conducted to obtain ultrasonic signals from different screw models and defect types. The received ultrasonic echo signals are then preprocessed, and mathematical features and signal information features are extracted from the preprocessed ultrasonic signals to construct a defect feature library. This library is then divided into a training set and a test set. The training set is then fed into a defect recognition model for training to determine the screw defect type. The test set is then fed into the defect recognition model to complete the training by identifying the screw defect type. The trained defect recognition model can then be used to identify the reflected echo signals.

[0074] 102. Extract key features from the torque-angle curve and match corresponding screw states in a screw state library;

[0075] The screw state library includes various screw states input through preliminary experiments. Each screw state corresponds to one or more key features. Key features can be set repeatedly or one-to-one. Key features include the overall smoothness of the observation curve, the torque rise slope, and the presence of significant torque mutation points.

[0076] Specifically, the key features include the slope of the curve and the slope change point. When extracting the key features from the torque-angle curve, first traverse the slope of the torque-angle curve, calculate the average value of the slope and determine whether the average value is greater than the preset gentle slope. If it is, output the rough state, otherwise output the standard state; secondly, obtain the number of times the slope is greater than the preset fluctuation slope. If the number is greater than the preset fluctuation value, output the screw state as a defective state, otherwise output the standard state; finally, determine whether the slope ratio before and after the slope change point is greater than the preset value. If so, output the screw state as a sudden change state, otherwise output the standard state.

[0077] Among them, when traversing the slope of the torque-angle curve, the torque-angle curve can be divided into the pre-tightening stage, the clamping stage, and the yield stage in sequence. In the pre-tightening stage, the screw contacts the fixed component for the first time. At this time, the torque applied is mainly to overcome the friction between the threads and the formation or locking resistance of the threads. In the clamping stage, the screw rod undergoes elastic deformation and generates axial clamping force. In the yield stage, the screw material exceeds the yield point and undergoes permanent plastic deformation. Since the three stages have different curve shapes, the slopes of the three stages can be calculated separately during analysis. When analyzing the roughness of the screw, the slope of the pre-tightening stage is mainly used for analysis. When analyzing the defect state and mutation state of the screw, the slopes of the pre-tightening stage and the clamping stage are mainly used for analysis.

[0078] Among them, preset values ​​such as the gentle slope, fluctuation value and slope ratio can be obtained through experiments.

[0079] 103. Query the preset pre-tightening parameters corresponding to the screw state, integrate the pre-tightening parameters, and output an adaptive final torque adjustment strategy. The final torque adjustment strategy is generated based on the screw state obtained in step 102, achieving closed-loop control. This not only enables data communication between the tightening assembly 20 and the torque assembly 30, but also fully utilizes data to achieve intelligent control, thereby improving the safety and reliability of the entire screw tightening process.

[0080] In a specific implementation, querying the preset pre-tightening parameter corresponding to the screw state includes the following steps:

[0081] Under normal circumstances, when the screw is in a standard state, it indicates good lubrication, good meshing, low stiffness, and low overall risk. The preload parameters are set to a high initial speed and a high torque threshold, and the operation is continued until the torque meets the torque threshold; the torque threshold can be reached quickly, improving work efficiency.

[0082] When the screw state is rough, indicating that the screw surface may be rough and the friction coefficient may be slightly high, the pre-tightening parameters are set to a low initial speed and a low torque threshold, and the screw is continuously operated until it is linearly decelerated when approaching the torque threshold, to ensure the reliability of the screw connection.

[0083] When the screw state is a defective state, it indicates that the tightening process fluctuates frequently, and there may be defects inside the screw, and the thread is damaged, so the tightening process is not smooth. The pre-tightening parameters are set to a low initial speed and a low torque threshold, and the operation is intermittent;

[0084] When the screw state is a sudden change state, it indicates that the screw may encounter foreign objects or thread slippage during tightening, causing hysteresis. The pre-tightening parameters are set to a low initial speed and a low torque threshold, and the screw is continuously operated until the change point, at which time the speed is briefly reduced.

[0085] Among them, the preload parameter is used to control the operation of the torque component 30. The initial speed in the preload parameter can be a constant value or a variable value calculated with the key feature as a variable. Those skilled in the art can set it according to actual needs.

[0086] The torque threshold is preset by setting a torque setting value, and different torque thresholds correspond to different percentages of the torque setting value. For example, the high torque threshold may be 90% of the torque setting value, and the low torque threshold corresponds to 60% of the torque setting value.

[0087] By sensing the characteristics, the risk status of the screw can be identified in advance, and the appropriate working mode can be pre-selected before entering the final torque control stage, avoiding the forced application of precise torque on the wrong or dangerous path.

[0088] The unique advantage of this application is that it optimizes the entire tightening process, especially the safety, efficiency and accuracy of the final torque application stage, through the information obtained in the sensing stage, ensuring that the target torque is applied accurately and reliably to avoid slippage, overload or insufficient preload. Based on the real-time data collected during the actual tightening process, combined with the preset screw state library, the final torque adjustment strategy is dynamically generated and output. It can adapt to the state of the screw and adjust the final torque adjustment strategy in real time to ensure the optimal and safe tightening effect. It avoids the problem of slippage and breakage caused by excessive preset torque, or loosening caused by too small a torque, and significantly improves the tightening accuracy and consistency when tightening multiple screws.

[0089] It should be understood that the application of this application is not limited to the above examples. For ordinary technicians in this field, they can make improvements or changes based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to this application.

Claims

1. An electric screwdriver with a torque wrench, characterized in that: include: Equipment housing; A tightening assembly, the tightening assembly being disposed in the device housing, the electric screw head comprising a first drive unit, a ratchet driver, and a screw head connected in sequence; A torque assembly, the torque assembly comprising a second drive unit, a planetary gear reducer, and a torque output shaft connected in sequence; A sensing assembly, the sensing assembly being sleeved on the screw head and the torque output shaft, the sensing assembly comprising a torque sensor and an angle sensor; A control component is disposed in the device housing and is electrically connected to the first drive unit, the second drive unit, and the sensor component.

2. The electric screwdriver with a torque wrench according to claim 1, characterized in that: The device housing includes a tightening part and a torque part perpendicular to each other, and the interiors of the tightening part and the torque part respectively form inner cavities for accommodating the tightening assembly and the torque assembly, and the tightening assembly and the torque assembly are respectively arranged on the tightening part and the torque part.

3. The electric screwdriver with a torque wrench according to claim 1, characterized in that: The device also includes an ultrasonic transducer and a receiver, which are both arranged in the device housing and located at the rear side of the tightening assembly.

4. The electric screwdriver with a torque wrench according to claim 1, characterized in that: The control component includes a main control circuit board and a wireless transmission unit, and the wireless transmission unit is electrically connected to the main control circuit board.

5. A torque wrench control method based on tightening characteristics, characterized in that: The torque wrench control method comprises the following steps: In response to the resistance change, a tightening feature library of the target screw is generated, angle data and torque data of the screw head when tightening the target screw are collected, and a torque-angle curve is constructed in the tightening feature library; Extracting key features from the torque-angle curve and matching corresponding screw states in a screw state library; The preset pre-tightening parameters corresponding to the screw state are queried, the pre-tightening parameters are integrated and an adaptive final torque adjustment strategy is output.

6. The torque wrench control method based on tightening characteristics according to claim 5, characterized in that: The step of extracting key features from the torque-angle curve comprises the following steps: Traversing the slopes of the torque-angle curve, calculating an average value of the slopes and determining whether the average value is greater than a preset gentle slope, if so, outputting a rough state, otherwise outputting a standard state; Obtaining the number of times the slope is greater than a preset fluctuation slope, and outputting the screw state as a defective state if the number is greater than a preset fluctuation value, otherwise outputting the screw state as a standard state; Determine whether the slope ratio before and after the slope change point is greater than the preset value. If so, output the screw state as a sudden change state, otherwise output the standard state.

7. The torque wrench control method based on tightening characteristics according to claim 6, characterized in that: The querying of the preset pre-tightening parameters corresponding to the screw state includes the following steps: When the screw state is a standard state, the pre-tightening parameters are set to a high initial speed and a high torque threshold, and the operation is continued until the torque meets the torque threshold; When the screw state is rough, the pre-tightening parameters are set to a low initial speed and a low torque threshold, and the screw is continuously operated until it is linearly decelerated when approaching the torque threshold. When the screw state is a defective state; the pre-tightening parameters are set to a low initial speed and a low torque threshold, and the operation is intermittent; When the screw state is a sudden change state, the pre-tightening parameters are set to a low initial speed and a low torque threshold, and the screw is continuously operated until the change point, at which time the speed is temporarily reduced.

8. The torque wrench control method based on tightening characteristics according to claim 5, characterized in that: After the torque-angle curve is constructed in the tightening feature library, the following steps are included: Identify the linear region of the torque-angle curve, calculate the slope of this region and calculate the material hardness; The yield point where the slope changes from linear to nonlinear is identified, the torque value and angle value corresponding to the yield point are recorded, and the hardness of the material is determined based on the position of the yield point in the torque-angle curve.

9. The torque wrench control method based on tightening characteristics according to claim 5, characterized in that: The step of generating a tightening feature library of a target screw comprises the following steps: A tightening strategy is output based on the tightening feature library of the first target screw, a feature set including multiple tightening feature libraries of the same type is constructed, key features in the feature set are comprehensively analyzed, and a torque adjustment strategy is output.

10. The torque wrench control method based on tightening characteristics according to claim 5, characterized in that: The output adaptive final torque adjustment strategy includes the following steps: Acquire the reflected echo signal of the ultrasonic wave; Extract the callback features in the reflected echo signal and compare them with the preset defect feature library to identify the defect information; The final torque adjustment strategy is adjusted according to the defect information and a prompt signal is output.

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