Multi-degree-of-freedom bolt screwing device

Abstract

The utility model relates to the field of steel box girder high-strength bolt operation, in particular to a multi-degree-of-freedom bolt screwing device which is used for being arranged on a multi-shaft moving support of a high-strength bolt automatic screwing machine so as to execute the bolt screwing action according to a received instruction. The multi-degree-of-freedom bolt screwing device comprises a screwing head main body, a transverse movement driving part and a connecting part, wherein the connecting part comprises a connecting frame, a central rotating shaft, a swinging group and a rotating group. The screwing head main body realizes translation through the movement of the transverse movement driving part; the central rotating shaft supports the screwing head main body to rotate; the swinging group drives the screwing head to radially swing around the central shaft; and the rotating group drives the rotating shaft to rotate or revolve. The integrated design endows the device with the multi-degree-of-freedom movement capacity of translation, rotation, swing and revolution, the capacity of automatically screwing bolts in different directions, angles or shielding positions in a complex space is greatly improved, and the device can be matched with machine vision intelligent recognition and automatic posture adjustment to ensure that the screwing action is rapid and accurate.

Description

Technical Field

[0001] The utility model relates to the field of high-strength bolt operations for steel box beams, in particular to a multi-degree-of-freedom bolt tightening device. Background Art

[0002] During the construction of large steel box girder bridges and the splicing of steel components in high-rise buildings, the tightening of high-strength bolts remains a critical step in the construction process. Currently, high-strength bolt connections on large steel components still rely primarily on workers using high-torque electric wrenches. This is prone to several issues: 1. High manual labor risk. When tightening high-strength bolts on large steel components like bridges, workers rely on simple hanging baskets or nets to perform the work at height, which poses significant safety risks. 2. High manual labor intensity. When splicing large steel components like steel box girders, workers are required to continuously operate electric torque wrenches weighing approximately 10 kg. The high-altitude working environment makes the manual labor extremely intensive. 3. Low manual labor efficiency. When workers continuously operate with electric wrenches, they need to reposition auxiliary tools such as hanging baskets each time they move, which reduces manual tightening efficiency. 4. Manual tightening stability is poor. High-intensity working conditions can easily lead to low consistency and reliability in bolt tightening, which will directly affect the overall connection construction quality of large steel components such as steel box girder bridges.

[0003] In order to solve the adverse effects of manual tightening operations, the design and development of automatic bolt tightening devices have attracted more and more attention. At present, there have been some reports on patents related to automatic bolt tightening, such as CN109317959A, CN217143022U, CN102720104B, etc. However, the design of the above-mentioned automatic bolt tightening device does not include a detailed introduction to the tightening module, and the tightening module plays a decisive role in the positioning accuracy, clamping reliability, and environmental adaptability of the entire automatic bolt tightening device. At present, the structural design of the tightening module in the above-mentioned patents is relatively simple and has great limitations, especially for the clamping of high-torque electric wrenches. In the equipment for automatically tightening high-strength bolts, the needs for adjusting the position, correcting the posture, and changing the tightening bolts are gradually becoming prominent. The current tightening devices or tools are difficult to meet the requirements of complex posture adjustment and flexible adjustment. Utility Model Content

[0004] In response to the above-mentioned technical problems, the utility model provides a multi-degree-of-freedom bolt tightening device, which uses a specially designed connecting part to connect the tightening part for tightening the bolt with the multi-axis movable support of the automatic tightening machine. For the tightening of high-strength bolts, multiple degrees of freedom of movement can be performed, which greatly improves its flexibility. It can better adapt to the current automatic tightening machines and other complex requirements such as multiple postures and posture correction.

[0005] The utility model provides a multi-degree-of-freedom bolt tightening device, which is arranged on a multi-axis movable support of a high-strength bolt automatic tightening machine and is used to perform bolt tightening actions according to received instructions. The multi-degree-of-freedom bolt tightening device includes a screw head body, a transverse driving part, and a connecting part; the screw head body is used to fix or tighten the high-strength bolt nut / screw head after docking; the transverse driving part is used to be connected to the multi-axis movable support of the high-strength bolt automatic tightening machine; the screw head body is arranged on the transverse driving part through the connecting part, and the above-mentioned connecting part is movably arranged on the transverse driving part, wherein the connecting part includes: a connecting frame, a central rotating shaft, a swinging group, and a rotating group; the connecting frame is movably arranged on the transverse driving part; the central rotating shaft is rotatable around its axis and is arranged on the connecting frame; the swinging group is connected to the central rotating shaft and is used to drive the screw head body to selectively swing in the radial direction of the central rotating shaft; the rotating group is connected to the central rotating shaft and is used to drive the screw head body to selectively rotate or revolve around the central rotating shaft.

[0006] This multi-degree-of-freedom bolt tightening device design organically integrates the screw head body, the lateral drive part and the connection part with multiple rotation and swing capabilities. It not only realizes the highly flexible movement of the tightening device on the multi-axis movable support, but also significantly improves its automated tightening capability for bolts in complex spaces.

[0007] The central axis, swing group, and rotation group integrated into the connection allow the screw head to flexibly adjust its posture in multiple degrees of freedom, including rotation around the axis, radial swing, and overall position translation, thereby accurately responding to bolt tightening requirements in different directions, angles, and even in obstructed or corner positions. This structure not only significantly improves the coverage and posture adaptability of the tightening operation, but also, based on this, cooperates with the machine vision system to achieve intelligent recognition and posture adjustment of the bolt position, ensuring fast, stable, and accurate tightening action, greatly improving construction efficiency and safety, reducing manual intervention and errors, and providing good hardware support, which is better suited to the needs of intelligent and flexible operations in high-strength bolt connection scenarios.

[0008] In some embodiments, the above-mentioned swing group includes a swing shaft, a first gear, a second gear, a third gear and a swing driving unit; the swing shaft is rotatably arranged on the central shaft along the radial direction of the central shaft; the first gear is arranged at one end of the above-mentioned swing shaft; the second gear is arranged at the other end of the above-mentioned swing shaft; the third gear is rotatably mounted on the above-mentioned central shaft, and the above-mentioned first gear and second gear are both engaged with the third gear; the swing driving unit is connected to the third gear for driving the third gear to rotate around the central shaft.

[0009] The design of the above-mentioned swing group is to set a radially arranged swing shaft on the central shaft, and configure a first gear and a second gear at both ends thereof, to achieve bilateral engagement with the third gear mounted on the central shaft, and then the swing drive unit drives the third gear to rotate around the central shaft, thereby driving the swing shaft to achieve swing control of the screw head body.

[0010] The advantage of this structure is that it enables stable, symmetrical, and controllable radial swing adjustment of the tightening head, enabling the tightening device to flexibly handle non-positive installation positions and significantly improving the tightening head's coverage of different bolt orientations. Furthermore, the aforementioned dual-gear meshing structure offers high transmission accuracy and resistance to off-center loads. Combined with a central drive mechanism, it avoids structural imbalance and response lag caused by unilateral transmission, contributing to a smoother and more efficient posture adjustment process.

[0011] In some embodiments, the first, second, and third gears are all bevel gears. This allows for efficient and stable angular transmission between different axes, and is particularly suitable for structural arrangements where an angle exists between the central axis and the swing axis. The bevel gear structure is also advantageous due to its excellent self-alignment properties and strong load-bearing capacity, allowing it to withstand significant reaction forces during tightening, maintaining stability in screw head position adjustment.

[0012] In some embodiments, the third gear comprises a front gear and a rear gear, the front gear being fixedly connected to the rear gear; the front gear is a bevel gear meshing with the first and second gears, while the rear gear is in transmission connection with the swing drive unit, driving the front gear to rotate about a central axis. Thus, the third gear is designed as a structure consisting of a fixed connection between the front and rear gears. The front bevel gear is focused on efficient angular transmission with the swing gears on both sides, ensuring precise radial swing of the screw head, while the rear gear is directly connected to the drive component, facilitating stable and concentrated transmission of driving force to the entire swing system.

[0013] In some embodiments, the swing drive unit includes a first motor and a first drive gear; the first motor is mounted on a connecting frame; the first drive gear is mounted on the main shaft of the first motor and meshes with a third gear, driving the third gear to rotate about its central axis. This enables direct, electronically controlled drive of the screwdriver's swing motion, resulting in fast response and high control accuracy. Placing the motor directly on the connecting frame effectively shortens the transmission chain, reduces energy loss and mechanical backlash, and improves the system's dynamic response.

[0014] In some embodiments, the above-mentioned rotating group includes a fourth gear and a rotating driving unit; the fourth gear is mounted on the central rotating shaft; the rotating driving unit is connected to the fourth gear for driving the central rotating shaft to rotate.

[0015] In some embodiments, the swing drive unit includes a first motor and a first drive gear; the first motor is disposed on a connecting frame; the first drive gear is mounted on a main shaft of the first motor, and the first drive gear is engaged with a third gear to drive the third gear to rotate around a central rotation axis;

[0016] The above-mentioned rotation drive part includes a second motor and a second drive gear; the second motor is arranged on the connecting frame; the first drive gear is mounted on the main shaft of the second motor, and the second drive gear is engaged with the fourth gear to drive the fourth gear to rotate around the central rotation axis; the above-mentioned first motor and second motor are respectively arranged on both sides of the connecting frame.

[0017] In some embodiments, the third gear and the fourth gear are in sliding contact, or a bearing or a friction washer mounted on the central shaft is provided between the third gear and the fourth gear.

[0018] In some embodiments, the above-mentioned tightening head body includes a tightening part and a tightening support; the tightening part is used to fix or tighten the high-strength bolt nut / screw head after docking; the above-mentioned tightening part is arranged on the tightening support; the tightening support is connected to both ends of the swing shaft.

[0019] In some embodiments, the lateral driving portion is a linear slide module, and the connecting portion is disposed on a slide of the linear slide module. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the external structure of a multi-degree-of-freedom bolt tightening device for illustrating an embodiment;

[0021] Figure 2 is a bottom-view structural diagram for illustrating a multi-degree-of-freedom bolt tightening device according to an embodiment;

[0022] Figure 3 is a schematic diagram of a top view of a multi-degree-of-freedom bolt tightening device for illustrating an embodiment;

[0023] Figure 4 is a schematic structural diagram of a side view of a multi-degree-of-freedom bolt tightening device according to an embodiment;

[0024] 1- screw head body; 110- tightening part; 120- tightening support;

[0025] 2- Transverse drive unit;

[0026] 3-connecting part; 310-connecting frame; 320-central rotating shaft; 330-swinging group; 331-swinging rotating shaft; 332-first gear; 333-second gear; 334-third gear; 334a-front gear; 334b-rear gear; 335-swinging driving part; 3351-first motor; 3352-first driving gear; 340-rotating group; 341-fourth gear; 342-rotating driving part; 3421-second motor; 3422-second driving gear. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application are described below in conjunction with the accompanying drawings in the embodiments of the present application. In the embodiments of the present application, words such as "exemplarily" or "for example" are used to indicate examples, illustrations or descriptions.

[0028] Example 1:

[0029] Combine Figure 1 、 Figure 2 、 Figure 3 and Figure 4 The utility model provides a multi-degree-of-freedom bolt tightening device, which adopts a specially designed connecting part 3. The connecting part 3 is connected to the multi-axis movable support of the automatic tightening machine through the tightening part for tightening the bolt. For the tightening work of high-strength bolts, it can perform multiple degrees of freedom movement, greatly improving its flexibility. It can better adapt to the complex needs of multiple postures, posture correction, etc. for the current automatic tightening machine.

[0030] The utility model provides a multi-degree-of-freedom bolt tightening device, which is arranged on a multi-axis movable support of a high-strength bolt automatic tightening machine and is used to perform bolt tightening actions according to received instructions. The multi-degree-of-freedom bolt tightening device includes a screw head body 1, a transverse driving part 2, and a connecting part 3; the screw head body 1 is used to fix or screw the high-strength bolt nut / screw head after docking; the transverse driving part 2 is used to be connected to the multi-axis movable support of the high-strength bolt automatic tightening machine; the screw head body 1 is arranged on the transverse driving part 2 through the connecting part 3, and the above-mentioned connecting part 3 is movable It is arranged on the transverse driving part 2, wherein the connecting part 3 includes: a connecting frame 310, a central rotating shaft 320, a swinging group 330, and a rotating group 340; the connecting frame 310 is movably arranged on the transverse driving part 2; the central rotating shaft 320 is arranged on the connecting frame 310 so as to rotate around its axis; the swinging group 330 is connected to the central rotating shaft 320, and is used to drive the screw head body 1 to selectively perform a swinging motion in the radial direction of the central rotating shaft 320; the rotating group 340 is connected to the central rotating shaft 320, and is used to drive the screw head body 1 to selectively perform a rotation or revolution motion around the central rotating shaft 320.

[0031] This multi-degree-of-freedom bolt tightening device achieves highly flexible automated tightening by organically integrating a screwdriver body 1, a traverse drive unit 2, and a connecting unit 3 with multiple rotation and swing capabilities. The core components of the connecting unit 3 include a central axis 320, an oscillation unit 330, and a rotation unit 340. This allows the screwdriver body 1 to flexibly adjust its posture and position, precisely addressing bolt tightening requirements in complex spaces.

[0032] Specifically, the central shaft 320 in the connecting portion 3 serves as the core component of the entire device, enabling the screwdriver body 1 to rotate about its axis, providing rotational capability. The swing assembly 330, on the other hand, enables the screwdriver body 1 to oscillate radially, flexibly adapting to various tightening angles. The rotation assembly 340 further enhances the device's flexibility, capable of driving the screwdriver body 1 to rotate or revolve, ensuring precise bolt alignment in complex operating environments.

[0033] The central rotating shaft 320 can use high-precision ball bearings or precision bearings to ensure stability and durability during rotation. In the swing group 330, a gear group can be used for transmission, and the gear transmission part can use a precision bevel gear or planetary gear system.

[0034] Besides using a gear transmission scheme to realize the swing assembly 330 and the rotation assembly 340, other transmission methods can also be used to achieve their purpose. For example, the swing assembly 330 can be driven pneumatically or hydraulically. By using an air cylinder or a hydraulic cylinder, a smooth and powerful swinging force can be provided. By adjusting the air pressure or hydraulic pressure, the swing angle can be precisely controlled.

[0035] The rotation group 340 can adopt a combination of a DC motor or a stepper motor and a precision reducer to achieve precise rotation or revolution control. The DC motor is combined with the reducer to ensure the stability and accuracy of the torque output. Of course, rotation can also be achieved by means of an electric cylinder, which can provide precise linear or rotational movement. The above-mentioned rotation group 340 and swing group 330 only need to reliably achieve their corresponding movement purposes. The above-mentioned transverse drive unit 2 can be a linear slide module, and the connecting part 3 is arranged on the slide of the linear slide module.

[0036] Example 2

[0037] Combine Figure 1 、 Figure 2 、 Figure 3 and Figure 4Based on the first embodiment, the solution can be further optimized. For example, the swing assembly 330 includes a swing shaft 331, a first gear 332, a second gear 333, a third gear 334, and a swing driving unit 335. The swing shaft 331 is rotatably mounted on the central shaft 320 along the radial direction of the central shaft 320. The first gear 332 is disposed at one end of the swing shaft 331. The second gear 333 is disposed at the other end of the swing shaft 331. The third gear 334 is rotatably mounted on the central shaft 320. The first gear 332 and the second gear 333 are both meshed with the third gear 334. The swing driving unit 335 is in driving connection with the third gear 334 to drive the third gear 334 to rotate about the central shaft 320. The first gear 332, the second gear 333, and the third gear 334 can be of different gear types as needed.

[0038] In this embodiment, the first gear 332, the second gear 333, and the third gear 334 are all bevel gears. This allows for efficient and stable angular transmission between different axes, and is particularly suitable for structural layouts where an angle is included between the central axis 320 and the swing axis 331. The bevel gear structure is also advantageous due to its excellent self-alignment properties and strong load-bearing capacity, allowing it to withstand significant reaction forces during the tightening process, maintaining stability in the screw head's posture adjustment.

[0039] The aforementioned oscillating shaft 331, the three sets of bevel gears (first gear 332, second gear 333, and third gear 334), and the highly responsive oscillating drive unit 335 are interconnected. The oscillating shaft 331 can be made of high-strength alloy steel, offering excellent bending and torsional rigidity, suitable for stable operation under complex operating conditions. The oscillating shaft 331 extends radially along the central axis 320 and can be equipped with bearings or sliding bushings for low-friction rotational support. The first and second gears 332, 333 are fixedly mounted at each end of the oscillating shaft 331, and high-precision bevel gears can be used.

[0040] The third gear 334 is mounted on the central shaft 320 and meshes with the two gears on both sides, thereby achieving symmetrical torque transmission and angle synchronization control. The third gear 334 can be equipped with a rolling bearing to reduce rotational resistance.

[0041] In this embodiment, during the movement, the symmetrical force design of the first gear 332 and the second gear 333 on both sides can effectively offset the unbalanced load and improve the swing stability and accuracy; the third gear 334 rotates on the central axis, which is conducive to a compact structure, small inertia and fast response.

[0042] Based on the above embodiment, further optimization can be performed, such as where the third gear 334 comprises a front gear 334a and a rear gear 334b, wherein the front gear 334a is fixedly connected to the rear gear 334b; the front gear 334a is a bevel gear that meshes with the first gear 332 and the second gear 333, and the rear gear 334b ​​is transmission-connected to the swing drive unit 335, which is used to drive the front gear 334a to rotate about the central rotation axis 320. Thus, the third gear 334 is designed to be a structure formed by the front gear 334a and the rear gear 334b ​​being fixedly connected. The front bevel gear is focused on efficient angular transmission with the swing gears on both sides, ensuring precise radial swing of the screw head, while the rear gear 334b ​​is directly connected to the drive component, which facilitates stable and concentrated transmission of driving force to the entire swing system.

[0043] The swing driving unit 335 includes a first motor 3351 ( Figure 1 The first motor 3351 is mounted on the connecting frame 310. The first drive gear 3352 is mounted on the main shaft of the first motor 3351 and meshes with the third gear 334, driving the third gear 334 to rotate about the central axis 320. This allows for direct, electronically controlled drive of the screwdriver's swinging motion, resulting in fast response and high control accuracy. Placing the motor directly on the connecting frame 310 effectively shortens the transmission chain, reduces energy loss and mechanical backlash, and improves the system's dynamic response.

[0044] Example 3

[0045] Combine Figure 1 、 Figure 2 、 Figure 3 and Figure 4 The above-mentioned rotating group 340 includes a fourth gear 341 and a rotating driving part 342; the fourth gear 341 is mounted on the central rotating shaft 320; the rotating driving part 342 is connected to the fourth gear 341 in transmission connection, and is used to drive the central rotating shaft 320 to rotate.

[0046] In some embodiments, the swing drive unit 335 includes a first motor 3351 and a first drive gear 3352. The first motor 3351 is disposed on the connecting frame 310. The first drive gear 3352 is mounted on the main shaft of the first motor 3351. The first drive gear 3352 is engaged with the third gear 334 to drive the third gear 334 to rotate about the central rotation axis 320.

[0047] The rotation driving unit 342 includes a second motor 3421 ( Figure 1The first and second motors 3351 and 3421 are respectively arranged on both sides of the connecting frame 310.

[0048] The swing drive unit 335 and the rotation drive unit 342 are designed to be driven by a first motor 3351 and a second motor 3421, respectively, located on either side of the connecting frame 310, driving corresponding gears (the first drive gear 3352 meshes with the third gear 334, and the second drive gear 3422 meshes with the fourth gear 341). This symmetrical layout not only provides a compact structure and a balanced center of gravity, but also enables independent and precise control of the screw head in multiple degrees of freedom. The two motors independently drive the swing and rotation mechanisms, avoiding drive interference and improving the system's control stability and response speed.

[0049] The first motor 3351 and the second motor 3421 are respectively installed on both sides of the connecting frame 310 to correspondingly drive the third gear 334 in the swing group 330 and the fourth gear 341 in the rotation group 340 to respectively control the swing and rotation (or revolution) actions.

[0050] In actual engineering, the first drive gear 3352 and the second drive gear 3422 are both small-module helical gears or bevel gears, which are respectively installed on their respective motor main shafts and mesh with the third gear 334 and the fourth gear 341, thereby driving the swing shaft 331 and the center shaft 320 to swing and rotate respectively.

[0051] The third gear 334 and the fourth gear 341 are mounted on the central shaft 320. They can be constructed with rolling bearings or wear-resistant sleeves to ensure smooth rotation and effective load sharing. To reduce frictional interference, a friction washer (such as PTFE or brass) can be placed between the two gears, or a thrust roller bearing can be used to support axial loads, ensuring that the two groups of motion do not interfere with each other.

[0052] The overall structure of this embodiment relies on motors symmetrically distributed on the left and right sides of the connecting frame 310, so that the center of gravity of the device is centered, thereby improving the dynamic stability of the equipment during operation; at the same time, the swing group 330 and the rotation group 340 are driven by independent motors respectively, and can be completely decoupled in the system control, facilitating precise adjustment of the posture and real-time response, greatly improving the adaptability to complex spatial postures during the tightening process of high-strength bolts.

[0053] In this embodiment, further optimization can be achieved by slidingly abutting the third gear 334 against the fourth gear 341, or by interposing a bearing or friction washer mounted on the central shaft 320 between the third gear 334 and the fourth gear 341. This effectively enables the two gears to operate independently on the shared central shaft 320, avoiding mechanical interference between the swing drive system and the rotation drive system, allowing the two motion mechanisms to operate independently, thereby reliably improving the system's freedom of movement. Furthermore, the use of the bearing or friction washer not only reduces frictional resistance between the gears, minimizing wear, but also enhances transmission stability and service life.

[0054] The screwdriver body 1 comprises a tightening portion 110 and a tightening support 120. The tightening portion 110 is used to secure or tighten the high-strength bolt, nut, or screw head after docking. The tightening portion 110 is mounted on the tightening support 120, which is connected to both ends of the swing shaft 331. This ensures that the tightening portion 110 maintains stable support and precise positioning during the tightening process. The connection between the tightening support 120 and the swing shaft 331 provides a solid foundation, allowing the screwdriver body 1 to maintain high precision during swinging or rotation, reducing errors caused by deviation or vibration.

[0055] This embodiment solves the problem of positioning and clamping high-strength bolts for continuous tightening on large steel components, effectively reducing the labor intensity and risk of manual clamping of electric wrenches; through the design of multi-degree-of-freedom modules, multiple sets of gears mesh and cooperate to adjust the posture of the tightening head, so that the tightening device can always reach the required tightening position with high precision, making the tightening range wider, and can tighten bolts in various parts of the steel box girder (front, bottom, corners, etc.), realizing the requirement that the tightening device can adapt to complex tightening environments.

[0056] A torque sensor can be installed at the end of the screwdriver body 1 to enable real-time detection and transmission of bolt torque data. The torque sensor is connected to the screwdriver head, which can use a 12-point plum blossom bit or a universal bit to connect and tighten hexagonal bolts of different angles, further improving the reliability and effectiveness of the connection between the socket bit and the bolt cap. When the tightening torque reaches the preset torque value, the electric wrench stops rotating, and the electric cylinder then drives the electric wrench and the fixing bracket to retract to the starting position.

[0057] By taking photos with an industrial camera and using data transmitted back by the relevant machine vision coordinate calibration system (the relevant solution has been disclosed by the applicant's previous patent), the exit route is planned, its movement on the linear slide module is controlled, and the direction of the entire tightening device is adjusted through the multi-degree-of-freedom module, and finally the user can smoothly exit the tightening work area.

[0058] During operation, an industrial camera and machine vision system first capture images and locate coordinates of the area to be tightened. The system then identifies and transmits information such as the bolt's position and posture to the control system. Subsequently, the traverse drive unit 2 drives the entire device on the multi-axis movable support of the high-strength bolt automatic tightening machine, bringing the entire device closer to the target bolt position. Next, fine positioning adjustment is performed via the connection unit 3. The central shaft 320 provides axial rotation. Driven by the swing drive unit 335 (composed of a first motor 3351 and a first drive gear 3352), the swing group 330 achieves flexible radial swinging of the screwdriver body 1 via the swing shaft 331, first gear 332, second gear 333, and third gear 334. Simultaneously, the rotation group 340, driven by the second motor 3421 and the second drive gear 3422, drives the fourth gear 341, enabling the screwdriver body 1 and its tightening portion 110 to rotate or revolve, ensuring precise alignment of the bolt in any posture.

[0059] After the alignment is completed, the tightening part 110 of the screw head body 1 (mounted on the tightening support 120 and connected to the swing shaft 331) is firmly docked with the bolt cap, and can be used with a 12-point plum blossom bit or a universal bit to improve the clamping performance. During the tightening process, the built-in torque sensor collects the tightening torque data in real time and feeds the data back to the control system for monitoring. When the torque reaches the preset value, the control system stops driving the electric wrench. During the tightening action, since the device has a highly flexible posture adjustment capability, it can adapt to the position of complex spaces such as in front of, below, and corners of the steel box girder, realizing accurate and efficient high-strength bolt tightening operations, greatly reducing the intensity and error of manual operation.

[0060] After tightening is completed, the electric wrench and its fixing bracket retract back to their original positions under the action of the electric cylinder. The machine vision system re-performs environmental detection and path planning, and controls the transverse drive unit 2 to drive the connecting unit 3 to smoothly exit the tightening area along the linear slide module. During the exit process, the rotating group 340 and the swinging group 330 cooperate to adjust the posture of the screw head body 1 to ensure that the device can smoothly avoid the surrounding structures without interference and collision. During the whole process, the third gear 334 and the fourth gear 341 are respectively rotated independently through bearings or friction washers to avoid transmission interference, making the system operation more stable and reliable.

[0061] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed within the present invention. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A multi-degree-of-freedom bolt tightening device, which is arranged on a multi-axis movable support of a high-strength bolt automatic tightening machine and is used to perform bolt tightening actions according to received instructions, and is characterized in that: The multi-degree-of-freedom bolt tightening device comprises: A screw head body, which is used to fix or screw the high-strength bolt nut / screw head after docking; A transverse driving unit, the transverse driving unit being used to connect to a multi-axis movable support of a high-strength bolt automatic tightening machine; The connecting part is provided on the transverse driving part through the connecting part, and the connecting part is movably provided on the transverse driving part. The connection part includes: A connecting frame, the connecting frame being movably disposed on the transverse driving portion; A central rotating shaft, which is rotatable about its axis and is arranged on the connecting frame; A swing group, which is connected to the central rotating shaft and is used to drive the screw head body to selectively swing in the radial direction around the central rotating shaft; The rotating group is connected to the central rotating shaft and is used to drive the screw head body to selectively rotate or revolve around the central rotating shaft.

2. The multi-degree-of-freedom bolt tightening device according to claim 1, characterized in that: The swing group includes: A swing shaft, the swing shaft being rotatably disposed on the central shaft in a radial direction of the central shaft; a first gear, the first gear being disposed at one end of the swing shaft; a second gear, the second gear being disposed at the other end of the swing shaft; a third gear, the third gear being rotatably mounted on the central shaft, the first gear and the second gear both being meshed with the third gear; The swing driving part is connected to the third gear in transmission mode and is used to drive the third gear to rotate around the central rotation axis.

3. The multi-degree-of-freedom bolt tightening device according to claim 2, characterized in that: The first gear, the second gear and the third gear are all bevel gears.

4. The multi-degree-of-freedom bolt tightening device according to claim 3, characterized in that: The third gear comprises a front gear and a rear gear, wherein the front gear is fixedly connected to the rear gear; The front gear is a bevel gear, which is engaged with the first gear and the second gear. The rear gear is in transmission connection with the swing driving part, and is used to drive the front gear to rotate around the central rotating shaft.

5. The multi-degree-of-freedom bolt tightening device according to claim 2, characterized in that: The swing driving unit includes: A first motor, the first motor being arranged on the connecting frame; The first driving gear is mounted on the main shaft of the first motor and is engaged with the third gear to drive the third gear to rotate around the central axis.

6. The multi-degree-of-freedom bolt tightening device according to claim 2, characterized in that: The rotation group includes: a fourth gear, the fourth gear being mounted on the central rotating shaft; The rotary drive unit is connected to the fourth gear and is used to drive the central shaft to rotate.

7. The multi-degree-of-freedom bolt tightening device according to claim 6, characterized in that: The swing driving unit includes: A first motor, the first motor being arranged on the connecting frame; A first driving gear, which is mounted on the main shaft of the first motor and meshes with the third gear to drive the third gear to rotate around the central axis; The rotary drive unit includes: a second motor, the second motor being arranged on the connecting frame; a second driving gear, the first driving gear being mounted on the main shaft of the second motor and meshing with the fourth gear to drive the fourth gear to rotate around the central axis; The first motor and the second motor are respectively arranged on both sides of the connecting frame.

8. The multi-degree-of-freedom bolt tightening device according to claim 7, characterized in that: The third gear and the fourth gear are in sliding contact, or a bearing or a friction washer sleeved on the central rotating shaft is provided between the third gear and the fourth gear.

9. The multi-degree-of-freedom bolt tightening device according to claim 2, characterized in that: The screwing head body comprises: A tightening part, which is used to fix or tighten the high-strength bolt nut / screw head after docking; a tightening support, wherein the tightening portion is arranged on the tightening support; The tightening support is connected to both ends of the swing shaft.

10. The multi-degree-of-freedom bolt tightening device according to claim 1, characterized in that: The transverse driving part is a linear slide module, and the connecting part is arranged on the slide of the linear slide module.

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