Symmetrical portal frame type multi-axis moving structure

Abstract

The utility model relates to the field of steel box girder operation equipment, in particular to a symmetrical portal frame type multi-shaft moving structure which is arranged on a high-strength bolt automatic tightening machine and comprises a moving part, a main cross beam and a vertical frame. The main cross beam is arranged on the moving part; the vertical frame is movably arranged on the cross beam, and the tightening assembly is movably arranged on the vertical frame; the vertical frame comprises an auxiliary cross beam and a door frame. The auxiliary cross beam is movably arranged on the main cross beam; the portal frame comprises lifting shafts which can be vertically and movably connected to the two ends of the auxiliary cross beam respectively, the upper ends of the two lifting shafts are connected through a connecting rod, the lower ends of the two lifting shafts are provided with two screwing heads which are in mirror symmetry relative to the central axis of the portal frame respectively, and the two screwing heads are used for being in butt joint with a screw rod and a nut respectively. According to the scheme, the symmetrical portal frame structures are arranged, so that the two screwing heads are arranged in a mirror image mode, synchronous clamping and rotary screwing of a high-strength bolt screw and a nut are achieved, and the phenomena of screw slipping and screw or nut follow-up are greatly reduced.

Description

Technical Field

[0001] The utility model relates to the field of steel box girder operation equipment, in particular to a symmetrical gantry type multi-axis moving structure. Background Art

[0002] In the steel structure bridge, especially the wide application of the steel box girder structure in large bridge projects, extremely high requirements are put forward for the quality of component connection. As the main connection means, the tightening quality of high-strength bolts is directly related to the stability and safety of the overall bridge structure. Therefore, during the manufacturing and construction process of steel box girders, a large number of high-strength bolts need to be precisely tightened.

[0003] In the prior art, manual cooperation with electric tools or manual tools is often used to tighten high-strength bolts. This method not only has a high labor intensity and low efficiency, but also is affected by the consistency of manual operation, resulting in unstable tightening torque and being difficult to meet the assembly requirements of large quantities, high consistency, and high precision.

[0004] In recent years, some high-strength bolt tightening devices with higher automation have also emerged. For example, an automatic tightening operation is achieved by using a single tightening head in cooperation with a multi-axis moving mechanism. However, there are still some problems with such devices. For example, unilateral tightening causes uneven axial force of the bolts. That is, the existing devices mostly adopt the unilateral tightening method, that is, the tightening force is only applied to one end of the bolt or nut. Such a unilateral tightening method is prone to thread slipping and loosening. That is, when tightening a stud, the nut may rotate together, and vice versa, affecting the tightening effect and the tightening efficiency. The unilateral tightening method is also prone to energy loss or reaction force deformation during the torque transmission process. Summary of the Utility Model

[0005] Aiming at the above technical problems, the utility model provides a symmetrical gantry type multi-axis moving structure, which mainly adopts a gantry type structure, so that the tightening heads for tightening can be symmetrically arranged. Through the symmetrical tightening method, not only can the situation of misalignment be avoided, but also the thread slipping, the phenomenon of the screw rod or nut following during tightening can be prevented when the two ends of the bolt are butted.

[0006] The utility model provides a symmetrical gantry type multi-axis mobile structure, which is arranged on a high-strength bolt automatic tightening machine for tightening high-strength bolts on a steel box beam, and comprises a moving part, a main crossbeam, and a vertical frame. The moving part is used to enable the multi-axis mobile structure as a whole to move on the top plate of the steel box beam; the main crossbeam is arranged on the moving part; the vertical frame is movably arranged on the crossbeam; the vertical frame comprises a secondary crossbeam and a gantry. The secondary crossbeam is movably arranged on the main crossbeam, and is used for selectively moving along the length direction of the main crossbeam; the portal frame includes lifting shafts which are respectively vertically movably connected to the two ends of the secondary crossbeam, and the upper ends of the two lifting shafts are connected by connecting rods to form a door frame structure, and the lower ends of the two lifting shafts are respectively provided with two screw heads which are mirror-symmetrical with respect to the central axis of the portal frame, and the two screw heads are respectively used for connecting the screws and nuts, that is, the two screw heads pass through the portal frame structure, so that the axes of the two screw heads can be located on the same straight line in three-dimensional space, and provide a basis for the centering of the tightening of high-strength bolts when the coordinates of the entire tightening machine and the steel box beam are correct and there is no offset.

[0007] In view of the problems caused by the current one-sided tightening of the tightening device structure, this solution sets up a symmetrical gantry structure to arrange the two screw heads in a mirror image, so as to achieve synchronous clamping and rotation tightening of high-strength bolts, screws and nuts, improve tightening accuracy and assembly efficiency, and greatly reduce the phenomenon of thread slippage, screw or nut follow-up.

[0008] In some embodiments, both ends of the secondary crossbeam are provided with lifting supports, and the lifting support sleeve is provided on the lifting shaft; the lifting shaft is provided with a first guide rail extending along the length direction of the lifting shaft, and the lifting support is provided with a lifting slide adapted to the first guide rail; the lifting shaft is provided with a first rack extending along the length direction of the lifting shaft, and the lifting support is provided with a first motor and a first gear, the first gear meshes with the first rack and is rotatably connected to the lifting support, and the first motor is connected to the rotating shaft of the first gear in a transmission manner, and is used to drive the lifting shaft to perform lifting motion on the secondary crossbeam when the first gear rotates. The gear rack transmission structure is used to achieve smooth lifting of the lifting shaft, improve vertical movement accuracy and load capacity, and enhance equipment stability.

[0009] In some embodiments, at least two first guide rails are provided, and at least two first guide rails are provided inside the gantry; the first gear is sleeved on the main shaft of the first motor and arranged in the gap between the lifting support and the lifting shaft. The multiple guide rails are used to improve the guiding stability, and the first gear is arranged in the structural gap, which effectively utilizes the space and ensures compact and reliable transmission. By providing a sub-beam lateral movement structure, the tightening system is allowed to flexibly move horizontally on the main beam.

[0010] In some embodiments, the middle section of the secondary beam is movably mounted on the main beam; the main beam is provided with a second guide rail extending along the length direction of the main beam, and the middle section of the secondary beam is provided with a transverse slide adapted to the second guide rail; the main beam is provided with a second rack extending along the length direction of the main beam, and the secondary beam is provided with a second motor and a second gear, the second gear meshes with the second rack and is rotatably connected to the secondary beam, and the second motor is connected to the rotating shaft of the second gear to drive the secondary beam to move laterally on the main beam when the second gear rotates. The transmission member is arranged in the gap between the two structures or driven by a transmission box to improve the compactness of the structure and the power transmission efficiency, while simplifying the wiring and installation.

[0011] In some embodiments, the second guide rail and the second rack are both arranged on the upper plate surface of the main beam; the second gear is mounted on the main shaft of the second motor and is arranged in the gap between the middle sections of the main beam and the secondary beam, or the second gear is rotatably connected to the secondary beam through a central shaft and is located in the gap between the middle sections of the main beam and the secondary beam, and the second motor is connected to the central shaft through a transmission box arranged on the outside of the secondary beam.

[0012] In some embodiments, the main beam is provided with two photoelectric limit switches located on both sides of the vertical frame, which are used to detect the distance between the secondary beam and the two photoelectric limit switches. The photoelectric limit switches are used to achieve non-contact precision detection, effectively prevent the secondary beam from running over the limit and ensure operational safety, and solve the problem of difficulty in positioning and preventing overtravel during the lateral movement of the secondary beam.

[0013] In some embodiments, the multi-axis movable structure also includes a tightening assembly, which is movably disposed on the vertical frame; the tightening assembly includes a tightening frame connected to the inner side of the portal frame, a first screw head and a second screw head disposed on the tightening frame, the first screw head and the second screw head are respectively used for docking or clamping high-strength bolts and nuts on the steel box girder, so as to drive the high-strength bolts to rotate according to the power unit configured according to the tightening assembly, thereby ensuring centering and synchronous rotation, and improving tightening consistency and torque transmission efficiency.

[0014] In some embodiments, the tightening frame includes a tightening seat, a linear module and a torque sensor. The tightening seat is used to support the second screw head or the first screw head; the tightening seat is arranged on the linear module, and is used to selectively move on the linear module; the torque sensor is arranged on the tightening seat, and the torque sensor is connected to the second screw head, and is used to collect torque data of the second screw head; the torque sensor is connected to the control unit, and the control unit is used to receive the dynamic signal of the torque sensor in real time and adjust the output parameters. The precise alignment of the tightening head is achieved through the linear module, and the torque sensor is used to collect real-time data and feed it back to the control unit, providing a hardware foundation for closed-loop control and dynamic adjustment.

[0015] In some embodiments, the above-mentioned tightening frame further includes a fixing plate, which is connected to the lower section of the lifting shaft and located inside the gantry; the above-mentioned linear module is arranged on the side surface of the fixing plate facing away from the lifting shaft. Reasonably arranging the tightening assembly inside the gantry structure and away from the lifting shaft improves the overall stability and further enhances the utilization efficiency of the installation space.

[0016] In some embodiments, the above-mentioned tightening assembly further includes an electric push cylinder, the cylinder body of which is connected or abutted against the fixing plate; the above-mentioned tightening seat includes a support seat and a screwing head seat. A third guide rail with an extending direction parallel to the screw direction of the electric push cylinder is arranged on the support seat; the screwing head seat is arranged on the above-mentioned third guide rail and connected to the screw of the electric push cylinder, and is used to push / pull back the above-mentioned screwing head seat when the electric push cylinder is activated; the above-mentioned first screwing head or second screwing head is arranged on the screwing head seat. By controlling the reciprocating movement of the screwing head seat on the guide rail with the electric push cylinder, high-precision and controllable clamping and releasing actions are realized.

[0017] The symmetric gantry-type multi-axis moving structure of the present utility model is arranged on an automatic high-strength bolt tightening machine, which is used to tighten the high-strength bolts on the steel box girder. The automatic high-strength bolt tightening machine includes a multi-axis moving support, a tightening assembly, and a control unit;

[0018] The multi-axis moving support has a moving part for enabling the automatic high-strength bolt tightening machine to move on the top plate of the steel box girder; the above-mentioned multi-axis moving support further includes a multi-axis support arranged on the moving part; the tightening assembly is used to dock or clamp the high-strength bolts on the steel box girder, and a power part configured according to the tightening assembly drives the high-strength bolts to rotate; the tightening assembly is arranged on the above-mentioned multi-axis support, and a driving assembly is configured on the multi-axis support to drive the tightening assembly to be movable on multiple spatial axes; the control unit is connected to the tightening assembly and the multi-axis moving support, and is used to control the tightening assembly and the multi-axis moving support according to the input instructions; wherein, the above-mentioned tightening assembly includes a tightening frame for clamping the steel box girder from both sides of the steel box girder and an image acquisition group for identifying the bolt position, and the control unit is connected to the image acquisition group and is used to generate a three-dimensional motion path based on the bolt position or pose data collected by the image acquisition group, and the above-mentioned tightening assembly tightens the high-strength bolts on the steel box girder in sequence according to the three-dimensional motion path; the two ends of the clamping of the above-mentioned tightening frame are respectively provided with a first screwing head for adapting to and fixing or screwing the nut of the high-strength bolt and a second screwing head for adapting to and fixing or screwing the high-strength screw rod. The three-dimensional motion path here can be a virtual channel with a width in the XZ plane, that is, there is a certain adjustable margin or amplitude in the direction of the channel width.

[0019] On this high-strength bolt automatic tightening machine, through the collaborative design of the multi-axis moving bracket and the machine vision system, the three-dimensional positioning and automatic tightening of high-strength bolts for steel box girders are realized. Specifically, the multi-axis moving support realizes planar movement on the top plate of the steel box girder through the moving part (such as an X / Y-axis platform driven by a servo), and its multi-axis bracket (such as a main beam, vertical frame, and lifting shaft can be set) provides three-dimensional spatial degrees of freedom, driving the tightening component to accurately adjust the position and pose to adapt to the distribution of the bolt group; the tightening component adopts a double-station design, the first wrench head (fitting the nut end) and the second wrench head (fitting the screw end) are respectively fixed on both sides of the gantry-type lifting shaft, and are symmetrically arranged with the image acquisition group to synchronously collect the position data of the nut and screw of the bolt, and a three-dimensional motion path can be generated to guide the centering. This structural design solves the problems of low efficiency and large error in traditional manual positioning, and provides a rigid support basis for automatic tightening.

[0020] In some embodiments, the above-mentioned multi-axis bracket includes a main beam and a vertical frame; the main beam is arranged on the moving part; the vertical frame is movably arranged on the cross beam, and the tightening component is movably arranged on the vertical frame; two photoelectric limit switches are arranged on the main beam on both sides of the vertical frame, and are used to respectively detect the distance between the vertical frame and the two photoelectric limit switches;

[0021] The above-mentioned vertical frame includes a secondary beam and a gantry; the secondary beam is movably arranged on the main beam and is used to selectively move along the length direction of the main beam; the gantry includes lifting shafts that are respectively vertically movably connected to both ends of the secondary beam, and the upper ends of the two lifting shafts are connected by a connecting rod to form a door frame structure, and the above-mentioned tightening component is arranged at the lower end of the lifting shaft; the first wrench head and the second wrench head are respectively located at the lower ends of the two lifting shafts and are arranged oppositely.

[0022] The photoelectric limit switches on the main beam real-time detect the moving range of the vertical frame to ensure the positioning accuracy, and the gantry structure realizes the adaptive adjustment of the tightening component in the Z-axis direction through the combination of the secondary beam and the lifting shaft, covering complex working surfaces such as the web and diaphragm of the steel box girder.

[0023] Specifically, this solution realizes the three-dimensional space positioning and synchronous tightening functions through the multi-stage motion design of the main beam, vertical frame, and gantry. The multi-axis bracket consists of a main beam (fixed to the moving part) and a vertical frame. The vertical frame horizontally moves along the length direction of the main beam (X-axis) through the secondary beam, and realizes height adjustment through the vertical movement (Z-axis) of the two lifting shafts on both sides, forming the movement ability of two degrees of freedom in X / Z. The gantry structure forms a door frame by connecting the upper ends of the two lifting shafts with a connecting rod to ensure the synchronous movement of the two lifting shafts on both sides. The first wrench head (fitting the nut) and the second wrench head (fitting the screw) are respectively installed at the lower ends of the two lifting shafts, and realize double-sided clamping tightening through the relative layout. Photoelectric limit switches are arranged on both sides of the main beam to real-time detect the moving range of the vertical frame (such as detecting the distance between the vertical frame and the limit switch), prevent over-travel, and calibrate the positioning accuracy.

[0024] The overall structure of this solution is designed modularly (such as replaceable screwing heads and rigid connection of gantry frames) to improve the adaptability to bolts of different specifications. At the same time, a multi-stage motion mechanism (horizontal drive of the main beam + vertical drive of the lifting shaft) is used to cover the operation requirements of bolt groups on the complex curved surface of the steel box girder.

[0025] In some embodiments, the above-mentioned tightening frame includes a tightening seat, a linear module, and a torque sensor; the tightening seat is used to support the second screwing head or the first screwing head; the tightening seat is arranged on the linear module and is used to move on the linear module selectively; the torque sensor is arranged on the tightening seat, and the torque sensor is connected to the second screwing head for collecting the torque data of the second screwing head; the torque sensor is connected to the control unit, and the control unit is used to receive the dynamic signal of the torque sensor in real time and adjust the output parameters. The above-mentioned torque sensor can be installed between the tightening seat and the second screwing head for detecting torque.

[0026] The dynamic adjustment and precise control of the tightening assembly are realized through the integrated design of the linear module and the torque sensor in this tightening frame. Specifically, the tightening seat realizes horizontal or vertical movement along a preset path through a linear module (such as a ball screw mechanism driven by a servo motor), so as to adjust the relative position between the second screwing head and the bolt; the torque sensor is directly integrated on the tightening seat, collects the torque data of the second screwing head in real time, and analyzes the dynamic signal through a control unit (such as a PLC or an industrial PC), and then adjusts output parameters such as the rotation speed and torque threshold of the servo motor. Among them, the rigid transmission characteristic of the linear module and the closed-loop feedback mechanism of the torque sensor work together to ensure that the tightening quality remains stable under complex working conditions. This structural design solves the problems of over-tightening / under-tightening caused by the lack of real-time force feedback in traditional tightening equipment.

[0027] In some embodiments, the above-mentioned image acquisition group includes: a first camera and a second camera; the first camera is arranged inside the first screwing head or on the tightening seat adjacent to the first screwing head; the second camera is arranged inside the second screwing head or on the tightening seat adjacent to the second screwing head; the above-mentioned first camera and the second camera are arranged opposite to each other and the imaging directions are on the same straight line in space.

[0028] In some embodiments, at least two ultrasonic rangefinders are arranged on the above-mentioned tightening frame, and the two ultrasonic rangefinders are arranged with parallel orientations; the ultrasonic rangefinders located on both sides of the steel box girder are arranged facing each other; the measuring direction of the above-mentioned ultrasonic rangefinder is parallel to the telescopic direction of the first screwing head or the second screwing head.

[0029] In some embodiments, an electromagnetic suction seat is arranged on the above-mentioned multi-axis bracket or moving part, and the electromagnetic suction seat is connected to the control unit for opening and closing the electromagnetic suction seat according to the instruction received by the control unit. Description of the Drawings

[0030] Figure 1 It is a schematic structural diagram of an automatic high-strength bolt tightening machine with a symmetric gantry multi-axis moving structure in the embodiment for illustration;

[0031] Figure 2 For illustration Figure 1 A partial enlarged view at position A in

[0032] Figure 3 For illustration Figure 1 A partial enlarged view at position B in

[0033] Figure 4 For illustration Figure 1 A partial enlarged view at position C in

[0034] Figure 5 It is a schematic side view structural diagram of the automatic high-strength bolt tightening machine in the embodiment for illustration;

[0035] Figure 6 For illustration Figure 5 A partial enlarged view at position D in

[0036] Figure 7 It is a schematic structural diagram of an automatic high-strength bolt tightening machine with a symmetric gantry multi-axis moving structure in the embodiment for illustration;

[0037] Figure 8 It is a schematic structural diagram of an automatic high-strength bolt tightening machine with a symmetric gantry multi-axis moving structure in the embodiment for illustration;

[0038] 100 - Multi-axis moving support; 110 - Moving part; 120 - Multi-axis bracket; 121 - Main crossbeam; 1211 - Second guide rail; 1212 - Transverse sliding seat; 1213 - Second rack; 122 - Vertical frame; 124 - Sub-crossbeam; 1241 - Lifting support; 1242 - Lifting sliding seat; 1243 - First motor; 1244 - First gear; 1245 - Second motor; 1246 - Second gear; 125 - Gantry; 126 - Lifting shaft; 1261 - First guide rail; 1262 - First rack; 127 - Connecting rod; 200 - Tightening assembly; 210 - Tightening frame; 2101 - Fixed plate; 211 - First screwdriver head; 212 - Second screwdriver head; 213 - Tightening seat; 2131 - Support seat; 2132 - Screwdriver head seat; 2133 - Third guide rail; 214 - Linear module; 300 - Photoelectric limit switch; 410 - First camera; 420 - Second camera; 500 - Ultrasonic distance meter; 600 - Electromagnetic suction seat; 700 - Electric push cylinder. Specific embodiments

[0039] The following describes the technical solutions in the embodiments of the present application with reference to 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 represent examples, illustrations or explanations.

[0040] Embodiment 1

[0041] Such as Figures 1 to 6 , a symmetric gantry multi-axis moving structure, which is arranged on an automatic high-strength bolt tightening machine for tightening high-strength bolts on a steel box girder. The multi-axis moving structure includes a moving part 110, a main cross beam 121, and a vertical frame 122; the moving part 110 is used to make the whole multi-axis moving structure movable on the top plate of the steel box girder; the main cross beam 121 is arranged on the moving part 110; the vertical frame 122 is movably arranged on the main cross beam 121;

[0042] The above vertical frame 122 includes a secondary cross beam 124 and a gantry 125; the secondary cross beam 124 is movably arranged on the main cross beam 121 and is used to selectively move along the length direction of the main cross beam 121; the gantry 125 includes lifting shafts 126 that are respectively vertically movably connected to both ends of the secondary cross beam 124. The upper ends of the two lifting shafts 126 are connected by a connecting rod 127 to form a door frame structure. The lower ends of the two lifting shafts 126 are respectively provided with two wrench heads that are mirror-symmetrical with respect to the central axis of the gantry 125. The two wrench heads are respectively used to dock the screw and the nut.

[0043] The symmetric structure of the gantry type used in this solution can ensure that when one end of the bolt is tightened relative to the other end, the bolt will not be misaligned. Multiple bolts can be parallel and perpendicular to the box girder during the tightening process according to a determined axis or reference line, ensuring the installation quality of the bolts.

[0044] The symmetric gantry multi-axis moving structure realizes symmetric arrangement in structure by respectively arranging lifting shafts 126 at both ends of the secondary cross beam 124 and forming a gantry 125 through a connecting rod 127. Wrench heads are respectively installed at the lower ends of the two lifting shafts 126 and are mirror-set with the central axis of the gantry 125 as the symmetry reference, so as to synchronously clamp and rotate the screw and nut on the steel box girder. This structure realizes synchronous and symmetric tightening of both ends of high-strength bolts, thus significantly reducing problems such as thread slipping, damage or assembly deviation caused by uneven force.

[0045] The auxiliary crossbeam 124 is connected to the guide rail on the main crossbeam 121 through the transverse sliding seat 1212 to achieve a lateral movable connection. The lifting shafts 126 at both ends are respectively set in the lifting support 1241, and the lifting function can be achieved through the gear-rack structure or the screw slider structure driven by the motor. The connecting rod 127 rigidly connects the upper ends of the two lifting shafts 126 through high-strength bolts to ensure the overall geometric stability and synchronization of the door frame 125. This kind of symmetrical design not only improves the tightening accuracy, but also helps to extend the service life of the bolts and tightening tools.

[0046] Embodiment 2

[0047] like Figures 1 to 6 On the basis of the above embodiment, lifting supports 1241 are provided at both ends of the secondary beam 124, and the lifting supports 1241 are sleeved on the lifting shaft 126; the lifting shaft 126 is provided with a first guide rail 1261 extending along the length direction of the lifting shaft 126, and the lifting support 1241 is provided with a lifting slide 1242 adapted to the first guide rail 1261; the lifting shaft 126 is provided with a first rack 1262 extending along the length direction of the lifting shaft 126, and the lifting support 1241 is provided with a first motor 1243 and a first gear 1244, the first gear 1244 is meshed with the first rack 1262 and is rotatably connected to the lifting support 1241, and the first motor 1243 is connected to the rotating shaft of the first gear 1244 for driving the lifting shaft 126 to perform lifting motion on the secondary beam 124 when the first gear 1244 rotates.

[0048] In this solution, lifting supports 1241 are provided at both ends of the secondary crossbeam 124. The lifting support 1241 is a hollow structure, which is sleeved on the outside of the lifting shaft 126. The above-mentioned first guide rail 1261 is preferably in the form of a rectangular raised track or a dovetail groove to improve the guiding accuracy. A lifting slide 1242 is provided inside the lifting support 1241. The lifting slide 1242 adopts a linear bearing or a guide rail slider structure, which is precisely matched with the first guide rail 1261, so that the lifting support 1241 can slide smoothly along the lifting shaft 126. The gear rotation is controlled by the first motor 1243, thereby driving the lifting support 1241 to move up and down along the lifting shaft 126. This structure ensures the stability and accuracy of the lifting movement through the precise matching of the guide rail and the lifting slide 1242, and avoids the problems of offset and jamming; the first gear 1244 is driven by the first motor 1243 to engage the rack to achieve automatic lifting adjustment.

[0049] Embodiment three:

[0050] like Figures 1 to 6On the basis of the above embodiment, two first guide rails 1261 are provided, and the two first guide rails 1261 are provided on the inner side of the door frame 125; the first gear 1244 is mounted on the main shaft of the first motor 1243 and arranged in the gap between the lifting support 1241 and the lifting shaft 126. In this solution, two first guide rails 1261 are provided, and are evenly distributed on the inner side of the door frame 125 of the lifting shaft 126 to enhance the overall guiding effect. The lifting slide 1242 adopts a double-row slider design, which has a larger contact area with multiple guide rails and an enhanced ability to resist lateral forces. The above-mentioned first gear 1244 is located in the compact space between the lifting support 1241 and the lifting shaft 126, and is directly driven by the motor. This solution adopts a double-row guide rail to improve the lifting motion accuracy. This solution is particularly suitable for heavy-load or long-stroke application scenarios to ensure that the lifting action is accurate and without shaking.

[0051] Embodiment 4:

[0052] like Figures 1 to 6 On the basis of the above embodiment, the middle section of the secondary beam 124 is movably mounted on the main beam 121; the main beam 121 is provided with a second guide rail 1211 extending along the length direction of the main beam, and the middle section of the secondary beam 124 is provided with a transverse slide 1212 adapted to the second guide rail 1211; the main beam 121 is provided with a second rack 1213 extending along the length direction of the main beam 121, and the secondary beam 124 is provided with a second motor 1245 and a second gear 1246, the second gear 1246 is meshed with the second rack 1213 and is rotatably connected to the secondary beam 124, the second motor 1245 is connected to the rotating shaft of the second gear 1246 for driving the secondary beam 124 to make lateral movement on the main beam 121 when the second gear 1246 rotates.

[0053] The middle section of the above-mentioned secondary beam 124 is hollowed out for being mounted on the main beam 121. This solution can realize the precise displacement of the vertical frame 122 along the length direction of the main beam 121, that is, through the guidance and rack-pinion drive cooperation between the secondary beam 124 and the main beam 121, the secondary beam 124 can accurately and stably move laterally along the length direction of the main beam 121. In this way, the position of the gantry 125 can be flexibly adjusted according to the position of the bolt distribution on the steel box beam to meet the needs of different working areas and improve the adaptability of automated operations. Such a structure combining a guide slide with a rack-pinion drive ensures that the deflection and jitter are reduced during the movement and positioning errors are avoided. Compared with traditional screw or belt drives, the rack-pinion structure is suitable for stable control of longer strokes.

[0054] Embodiment five:

[0055] like Figures 1 to 6, based on the above embodiments, the second guide rail 1211 and the second rack 1213 are both provided on the upper plate surface of the main cross beam 121; the second gear 1246 is sleeved on the main shaft of the second motor 1245 and is arranged in the gap between the middle sections of the main cross beam 121 and the auxiliary cross beam 124, or the second gear 1246 is rotatably connected to the auxiliary cross beam 124 through a central rotating shaft and is located in the gap between the middle sections of the main cross beam 121 and the auxiliary cross beam 124, and the second motor 1245 is drivingly connected to the central rotating shaft through a transmission box arranged outside the auxiliary cross beam 124.

[0056] In this embodiment, the second guide rail 1211 and the second rack 1213 are both arranged on the upper plate surface of the main cross beam 121, making them close to the central axis of the main cross beam 121, reducing structural deformation and improving stability. At the same time, the second gear 1246 and the motor drive structure are hidden in the "middle section gap" between the main cross beam 121 and the auxiliary cross beam 124, reducing the risk of exposed components.

[0057] This embodiment provides two transmission arrangement schemes to adapt to different equipment sizes and assembly methods. One is the direct drive connection method (the second gear 1246 is directly sleeved on the motor main shaft). In this way, the structure is simple, the response is fast, and the control accuracy is high, which is more suitable for the situation where there is sufficient space and the motor can be directly installed in the middle of the auxiliary cross beam 124. An indirect transmission method (central rotating shaft + transmission box) can also be adopted, that is, the second gear 1246 is connected through a central rotating shaft, and the rotating shaft passes through the middle section of the auxiliary cross beam 124; the motor is arranged outside the auxiliary cross beam 124 and drives the central rotating shaft to rotate through a transmission box (such as a synchronous pulley set or a gear set). This can avoid the motor invading the middle space of the auxiliary cross beam 124, and is also beneficial to heat dissipation, maintenance, and wiring; the central rotating shaft can be provided with a bearing seat for support to improve the transmission stability and the gear meshing accuracy, so as to realize the transmission process of motor rotation → transmission box → central rotating shaft rotation → gear meshing to drive the lateral movement of the auxiliary cross beam 124.

[0058] Two parallel second guide rails 1211 are provided on the upper surface of the main cross beam 121, and a matching transverse sliding seat 1212 (such as a linear slider or a V-shaped slider) is provided under the middle section of the auxiliary cross beam 124 to ensure that the auxiliary cross beam 124 makes a stable, low-friction, and non-yawing lateral movement on the main cross beam 121.

[0059] Embodiment Six:

[0060] As Figures 1 to 6, on the basis of the above embodiments, two photoelectric limit switches 300 are provided on the main crossbeam 121 on both sides of the vertical frame 122, which are used to detect the distances between the auxiliary crossbeam 124 and the two photoelectric limit switches 300 respectively. That is, the two photoelectric limit switches 300 are respectively arranged at the left and right end positions of the main crossbeam 121; when the auxiliary crossbeam 124 moves close to either side, the corresponding photoelectric switch will be triggered; the system judges whether the current auxiliary crossbeam 124 is close to the limit travel position accordingly, so as to achieve early deceleration and anti-collision protection, thus avoiding overshoot, avoiding structural damage or jamming, and preventing the auxiliary crossbeam 124 from "hitting the wall" due to misoperation. During implementation, the photoelectric switch signal can be connected to a PLC, a motion control card or an embedded control unit to monitor the running track of the auxiliary crossbeam 124 in real time. This solution uses the photoelectric limit switch 300, such non-contact induction has no mechanical wear, and at the same time has a fast response speed and high precision.

[0061] When setting, each photoelectric limit switch 300 is fixed on the upper surface or the inner side wall surface of the main crossbeam 121; the sensing direction of the switch faces the moving path of the auxiliary crossbeam 124; a reflector or a light-shielding sheet can also be arranged on the auxiliary crossbeam 124 for triggering the photoelectric switch. In the arrangement form, a transmissive type or a reflective type photoelectric switch can be used; install a pair of left limit and right limit; when the auxiliary crossbeam 124 approaches the limit point, its reflector enters the detection range, and the light path is reflected / blocked, thereby generating a limit signal.

[0062] Embodiment Seven:

[0063] As Figures 1 to 6 , on the basis of the above embodiments, this multi-axis moving structure further includes a tightening assembly, which is movably arranged on the vertical frame 122; the tightening assembly includes a tightening frame 210 connected to the inner side of the gantry 125, a first screwdriver head 211 and a second screwdriver head 212 arranged on the tightening frame 210, and the first screwdriver head 211 and the second screwdriver head 212 are respectively used to dock or clamp the high-strength bolts and nuts on the steel box girder, so as to drive the high-strength bolts to rotate according to the power unit configured by the tightening assembly.

[0064] The design of this solution can achieve the clamping and synchronous operation of high-strength bolts and nuts by positioning the two screwdriver heads on the tightening frame 210 respectively, so as to achieve the effect of automatic and precise tightening. The main technical advantage of this structure is that the symmetrical structure can realize the stable docking and clamping at both ends of the bolt and the nut, improve the axial alignment and torque transmission efficiency during the tightening process, and is particularly suitable for batch fastening operations of large components such as steel box girders.

[0065] In terms of the connection method, the tightening frame 210 is usually fixed to the structural member inside the gantry 125 by bolts, welding or chute methods to ensure the rigidity of the structure and the alignment accuracy. The first tightening head 211 and the second tightening head 212 are installed on the tightening frame 210 and are connected to a power device (such as a servo motor or a hydraulic motor) through a flange or a connecting piece to achieve power transmission and torque output. In addition, a wiring channel or a cable drag chain can be reserved inside the tightening frame 210 for connecting a control unit to realize closed-loop control of the tightening process, thereby ensuring uniform stress on each bolt connection point.

[0066] Embodiment Eight:

[0067] As Figures 1 to 6 , on the basis of the above embodiment, the tightening frame 210 includes a tightening seat 213, a linear module 214 and a torque sensor. The tightening seat 213 is used to support the second tightening head 212 or the first tightening head 211; the tightening seat 213 is arranged on the linear module 214 and is used to move on the linear module 214 selectively; the torque sensor is arranged on the tightening seat 213, and the torque sensor is connected to the second tightening head 212 for collecting torque data of the second tightening head 212; the torque sensor is connected to a control unit, and the control unit is used to receive the dynamic signal of the torque sensor in real time and adjust the output parameters. The control unit can be arranged at the lower end of the auxiliary cross beam 124 and is configured with a box body.

[0068] The torque sensor collects the actual torque value output by the tightening head in real time to achieve dynamic and accurate torque control, avoiding bolt damage or insufficient tightening. The control unit can be set to perform closed-loop adjustment of parameters according to the sensor feedback data, so as to stop tightening when the preset torque is reached, realizing automatic determination of whether the bolt is qualified, avoiding the situation of thread slipping and bolt shearing caused by excessive torque, and also avoiding structural loosening and fatigue failure caused by insufficient torque. The tightening seat 213 is installed on the sliding table of the linear module 214 and can move precisely in the horizontal direction through an electric sliding table; the above linear module 214 can be an electric sliding table (with a ball screw or a synchronous belt); the tightening seat 213 is fixed to the moving slider of the module by a bottom plate or flange screws; the module is driven by a servo motor and is connected to a PLC or a motion control system to control its precise movement. The torque sensor (such as a dynamic rotary type) is installed between the drive shaft and the tightening head and is connected through a coupling to realize signal transmission from the motor output shaft to the input end of the torque sensor, and then the output end of the torque sensor feeds back to the input shaft of the second tightening head 212. The flange connection or key connection method can be adopted, depending on the transmission structure.

[0069] Embodiment Nine:

[0070] As Figures 1 to 6, on the basis of the above embodiments, the tightening frame 210 further includes a fixing plate 2101, which is connected to the lower section of the lifting shaft 126 and is located inside the gantry 125; the linear module 214 is arranged on the side surface of the fixing plate 2101 facing away from the lifting shaft 126.

[0071] The tightening assembly further includes an electric push cylinder 700, the cylinder body of which is connected or abutted against the fixing plate 2101; the tightening seat 213 includes a support seat 2131 and a screwdriver head seat 2132, and a third guide rail 2133 with an extending direction parallel to the screw rod direction of the electric push cylinder 700 is arranged on the support seat 2131; the screwdriver head seat 2132 is arranged on the third guide rail 2133 and is connected to the screw rod of the electric push cylinder 700, and is used to push / pull back the screwdriver head seat 2132 when the electric push cylinder 700 is activated; the first screwdriver head 211 or the second screwdriver head 212 is arranged on the screwdriver head seat 2132.

[0072] In this embodiment, by introducing the combination of the fixing plate 2101, the linear module 214 and the electric push cylinder 700 in the tightening frame 210, the screwdriver head can achieve precise linear advancement or retraction in a specific direction. Installing the fixing plate 2101 at the lower section of the lifting shaft 126 and arranging the linear module 214 on the side of the fixing plate 2101 not only optimizes the structural layout, saves space, but also facilitates modular installation and maintenance. At the same time, by arranging the third guide rail 2133 with the same direction as the screw rod of the electric push cylinder 700 on the support seat 2131, it is ensured that the screwdriver head seat 2132 can move stably along the predetermined trajectory under the drive of the electric push cylinder 700, thereby effectively avoiding lateral shaking or positioning errors and improving the rigidity and reliability of the tightening process.

[0073] The above fixing plate 2101 can be rigidly connected to the end of the lifting shaft 126 by means of threaded connection or positioning pins to ensure that the whole tightening assembly rises or falls synchronously with the lifting movement. The linear module 214 can be installed on the side of the fixing plate 2101 by screws or chutes, and its own structure has a guiding slide rail and a servo motor drive system; the cylinder body of the electric push cylinder 700 is installed on the fixing plate 2101 through a support or flange, and the screw rod output end is connected to the bottom of the screwdriver head seat 2132. The screwdriver head seat 2132 is installed on the third guide rail 2133 to ensure that it makes a linear reciprocating motion driven by the screw rod, and the screwdriver head is connected to the screwdriver head seat 2132 through a quick-change joint or flange, which is convenient for maintenance and replacement. The overall system cooperation realizes accurate alignment and stable clamping at the tightening station.

[0074] Embodiment Ten:

[0075] As Figure 7 and Figure 8, The high-strength bolt automatic tightening machine is used to tighten the high-strength bolts on the steel box girder. The high-strength bolt automatic tightening machine includes a multi-axis moving support 100, a tightening assembly 200, and a control unit;

[0076] The multi-axis moving support 100 has a moving part 110 for moving the high-strength bolt automatic tightening machine on the top plate of the steel box girder; the multi-axis moving support 100 further includes a multi-axis bracket 120 provided on the moving part 110; the tightening assembly 200 is used to dock or clamp the high-strength bolts on the steel box girder, and the power part configured according to the tightening assembly 200 drives the high-strength bolts to rotate; the tightening assembly 200 is provided on the multi-axis bracket 120, and a driving assembly is configured on the multi-axis bracket 120 to drive the tightening assembly 200 to be movable on multiple spatial axes; the control unit is connected to the tightening assembly 200 and the multi-axis moving support 100 for controlling the tightening assembly 200 and the multi-axis moving support 100 according to the input instructions; wherein, the tightening assembly 200 includes a tightening frame 210 for clamping the steel box girder from both sides of the steel box girder and an image acquisition group for identifying the bolt position, and the control unit is connected to the image acquisition group for generating a three-dimensional motion path through the bolt position or pose data collected by the image acquisition group, and the tightening assembly 200 sequentially performs bolt tightening work according to the three-dimensional motion path; first screw heads 211 for adapting and fixing or screwing the nuts of the high-strength bolts and second screw heads 212 for adapting and fixing or screwing the high-strength screw rods are respectively arranged at both ends clamped by the tightening frame 210.

[0077] This multi-axis moving support 100 is the core support and moving platform of the high-strength bolt automatic tightening machine, and its function is to enable the whole machine to move and position flexibly and accurately on the top plate of the steel box girder. This multi-axis moving support 100 can be an XYZ three-axis motion platform, driven by a servo motor and a ball screw to achieve high-precision three-dimensional movement, or it can be a robot arm structure with a multi-joint design, providing a larger moving range and flexibility. As long as it can ensure that the machine accurately reaches the specified position on the top plate of the steel box girder.

[0078] The above-mentioned moving part 110 can be a part of the multi-axis moving support 100, responsible for driving the physical displacement of the whole machine on the top plate of the steel box girder to ensure that the whole device can move smoothly on the top surface of the steel box girder. Here, the moving part 110 can be a wheeled chassis equipped with a motor and rubber wheels, moving on the top plate of the steel box girder by electric drive, or a suspended moving system can be adopted, sliding on the top plate of the steel box girder fixed by a slide rail or a guide rail, etc.

[0079] The multi-axis support 120 can be used as a part of the multi-axis mobile support 100 to support the tightening assembly 200 and provide multi-axis motion capability. It can be a gantry structure that provides linear motion capability of the X, Y, and Z axes. As long as it can support the tightening assembly 200 and achieve precise movement, it can also be a multi-joint robotic arm that drives the tightening assembly 200 to move in three-dimensional space through joint motors and flexibly adjusts its posture.

[0080] The above-mentioned first screw head 211 and second screw head 212 are devices that directly interact with high-strength bolts and are responsible for docking, clamping and rotating the bolts. The tightening action is completed by the drive of the power unit. Its appearance can be an electric wrench that rotates the bolts through a motor drive, or it can be a pneumatic tightening tool that extends in the radial direction like a clamp and uses compressed air to provide high torque output. It can also use smart wrenches and socket wrenches with force feedback, etc., which adapt to the shape and size of the nut and automatically adjust the torque and speed through sensors.

[0081] The tightening frame 210 is designed as a frame mechanical structure, on which an electric push cylinder 700 or a hydraulic cylinder, etc. can be configured to drive the first screwing head 211 and the second screwing head 212 to move in the axial direction.

[0082] The control unit can be an industrial computer running dedicated control software to process input instructions and sensor data, or a PLC (programmable logic controller) or embedded system, as long as it can meet the real-time control requirements. The image acquisition group can include multiple high-definition cameras installed on the side of the tightening frame 210 facing the steel box girder to capture the two-dimensional image of the bolt, or a laser scanner to generate three-dimensional point cloud data of the bolt, and an infrared sensor can be configured to assist in identifying the bolt in a low-light environment, as long as it can adapt to different environmental conditions.

[0083] The above-mentioned power unit can be a servo motor, a pneumatic motor or a hydraulic system, as long as it can provide precise rotational force. The driving assembly is used to drive the tightening assembly 200 to move on multiple spatial axes to ensure that it can reach the bolts at different positions on the steel box girder. It can include a linear motor and a guide rail to achieve the linear movement of the tightening assembly 200. The three-dimensional motion path in this scheme is a motion trajectory generated by the control unit based on the bolt position or posture data collected by the image acquisition group, which is used to guide the movement of the tightening assembly 200. It can be generated by an algorithm. The three-dimensional motion path can also be a pre-programmed range channel trajectory, which is set according to the bolt distribution law. The bolts close to or covering the range are tightened in sequence. The path can be dynamically adjusted through real-time visual feedback to adapt to changes in the bolt position.

[0084] This embodiment proposes a symmetric gantry - type multi - axis moving structure. Through the collaborative design of the multi - axis moving bracket and the advanced machine vision system, the three - dimensional spatial precise positioning and efficient automatic tightening operation of high - strength bolts of steel box girders are realized.

[0085] The multi - axis moving support 100 can adopt an X / Y - axis motion platform driven by a servo motor, which can achieve high - precision two - dimensional planar movement on the surface of the steel box girder top plate, ensuring the flexible deployment of the tightening machine on complex working surfaces. At the same time, the multi - axis bracket 120 provides the multi - degree - of - freedom (X / Y / Z - axis) motion ability in three - dimensional space through its carefully designed structure (such as the combination of the main cross - beam 121, vertical support frames, and lifting shaft 126), enabling the tightening assembly 200 to dynamically adjust its posture according to the spatial distribution of the bolt group to meet the requirements of precise alignment. The tightening assembly 200 adopts an innovative double - station design. The first screwdriver head 211 adapts to and fixes or turns the nut end of the high - strength bolt, and the second screwdriver head 212 is for the screw end. The two are respectively installed on both sides of the gantry 125 - type lifting shaft 126 to form a stable clamping and screwing system. In addition, the image acquisition group equipped in the tightening assembly 200 is arranged in a symmetric layout. The spatial position data of the bolt nut and screw are synchronously collected through high - resolution vision sensors, and combined with image - processing algorithms to generate an accurate three - dimensional motion path, thereby guiding the tightening assembly 200 to complete high - precision centering operations. This structural design effectively overcomes the limitations of the traditional manual positioning method, such as low efficiency, large errors, and difficult - to - guarantee consistency, provides a solid rigid support foundation for the automatic screwing of high - strength bolts of steel box girders, and significantly improves the construction efficiency.

[0086] Example Eleven:

[0087] Based on the above - mentioned Embodiment One, the above - mentioned multi - axis bracket 120 includes a main cross - beam 121 and a vertical frame 122. The main cross - beam 121 is arranged on the moving part 110. The vertical frame 122 is movably arranged on the main cross - beam 121, and the tightening assembly 200 is movably arranged on the vertical frame 122. Two photoelectric limit switches 300 are arranged on the main cross - beam 121 on both sides of the vertical frame 122, which are used to detect the distances between the vertical frame 122 and the two photoelectric limit switches 300 respectively.

[0088] The above - mentioned vertical frame 122 includes a secondary cross - beam 124 and a gantry 125. The secondary cross - beam 124 is movably arranged on the main cross - beam 121 and is used to move selectively along the length direction of the main cross - beam 121. The gantry 125 includes lifting shafts 126 that are respectively vertically movably connected to both ends of the secondary cross - beam 124. The upper ends of the two lifting shafts 126 are connected by a connecting rod 127 to form a door - frame structure. The above - mentioned tightening assembly 200 is arranged at the lower end of the lifting shaft 126. The first screwdriver head 211 and the second screwdriver head 212 are respectively located at the lower ends of the two lifting shafts 126 and are arranged oppositely.

[0089] The utility model significantly improves the positioning accuracy and operation adaptability through the designed multi-stage motion mechanism and detection system. The photoelectric limit switch 300 configured on the main crossbeam 121 can monitor the moving range of the vertical frame 122 in real time, accurately detect the distance between the vertical frame 122 and the limit switch through high-sensitivity photoelectric induction technology, ensure that the positioning accuracy is controlled within millimeters, thus effectively avoiding over-travel phenomena and providing a reliable calibration basis for the system. At the same time, the gantry 125 structure realizes the height adaptive adjustment of the tightening assembly 200 in the Z-axis direction through the coordinated combination of the secondary crossbeam 124 and the lifting shaft 126, and its motion range is sufficient to cover the diverse requirements of complex working surfaces such as the web and diaphragm of the steel box girder.

[0090] In terms of structural design, this solution adopts a multi-stage motion system composed of the main crossbeam 121, the vertical frame 122 and the gantry 125, realizing the functions of high-efficiency positioning and synchronous tightening in three-dimensional space. The main crossbeam 121 can be welded from high-strength steel (such as Q345B steel) or made of lightweight and high-rigidity aluminum alloy profiles (such as 6061-T6) through precision machining. It is fixed on the moving part 110 to provide stable horizontal support for the entire system. The vertical frame 122 realizes horizontal movement along the length direction (X-axis) of the main crossbeam 121 through the secondary crossbeam 124. The secondary crossbeam 124 can be equipped with a ball screw drive mechanism or a linear motor drive to ensure smooth and high-precision displacement control. In addition, the lifting shafts 126 on both sides of the vertical frame 122 realize vertical movement (Z-axis) through a gear-rack system or a hydraulic cylinder driven by a servo motor, forming a two-degree-of-freedom motion ability in the X / Z directions. The gantry 125 structure consists of the upper ends of two lifting shafts 126 forming an integral door frame through high-strength connecting rods 127 (such as carbon steel welded parts or integrally formed aluminum alloy rods), ensuring the synchronism and rigidity of the two sides of the lifting shafts 126. The first wrench head 211 (fitted to the nut end) and the second wrench head 212 (fitted to the screw end) are respectively installed at the lower ends, and bilateral clamping tightening operations are realized through symmetric layout. The photoelectric limit switches 300 on both sides of the main crossbeam 121 adopt industrial-grade photoelectric sensors (such as infrared or laser types) to monitor the dynamic position of the vertical frame 122 in real time, and the detection accuracy can reach ±0.1 mm, effectively preventing motion overrun and optimizing positioning calibration.

[0091] The overall structure of this solution adopts modular design. For example, the first wrench head 211 and the second wrench head 212 can be designed as quickly replaceable tool heads to support the adaptation requirements of different specifications of bolts (such as M20, M24); the rigid connection of the gantry 125 is fixed by high-strength bolts or pins to ensure structural stability. At the same time, the combination of the horizontal drive of the main crossbeam 121 and the vertical drive of the lifting shaft 126 can flexibly meet the distribution requirements of bolt groups on the complex curved surface of the steel box girder (such as the junction of the web and the diaphragm). In this way, not only the entire working surface is covered, but also the tightening efficiency is significantly improved through the high-rigidity structure and precise motion control.

[0092] Embodiment Twelve:

[0093] Based on the above embodiments, the tightening frame 210 includes a tightening seat 213, a linear module 214, and a torque sensor; the tightening seat 213 is used to support the second tightening head 212 or the first tightening head 211; the tightening seat 213 is arranged on the linear module 214 and is used to move on the linear module 214 selectively; the torque sensor is arranged on the tightening seat 213, and the torque sensor is connected to the second tightening head 212 and is used to collect the torque data of the second tightening head 212; the torque sensor is connected to the control unit, and the control unit is used to receive the dynamic signal of the torque sensor in real time and adjust the output parameters.

[0094] In this embodiment, the tightening seat 213 is used as the core load-bearing component, and precise displacement control along the preset path is realized relying on the linear module 214. The linear module 214 can adopt a ball screw mechanism driven by a servo motor, and its high-rigidity transmission characteristics ensure the smooth movement of the tightening seat 213 in the horizontal or vertical direction, so as to accurately adjust the relative position between the second tightening head 212 and the target bolt; or an optional slide rail system driven by a linear motor can be selected to provide a higher dynamic response speed and positioning accuracy, up to ±0.01 mm. At the same time, the torque sensor is directly embedded in the stress node of the tightening seat 213, and can collect the torque data of the second tightening head 212 during the tightening process in real time, with an accuracy of up to ±0.1 N·m. The control unit can select an industrial-grade PLC or a high-performance industrial PC, and perform real-time analysis on the collected data through the built-in high-speed signal processing algorithm, and then dynamically adjust the operating parameters of the servo motor, such as rotational speed, torque threshold (supporting multi-level setting, such as initial tightening of 10 N·m and final tightening of 50 N·m), etc., to meet the tightening requirements under different working conditions.

[0095] Through the above design, the tightening frame 210 realizes excellent performance in dynamic adjustment and high-precision control of the tightening assembly 200 through the high integration of the linear module 214 and the torque sensor.

[0096] Embodiment Thirteen:

[0097] Based on the above embodiments, the image acquisition group includes: a first camera 410 and a second camera 420; the first camera 410 is arranged inside the first tightening head 211 or on the tightening seat 213 adjacent to the first tightening head 211; the second camera 420 is arranged inside the second tightening head 212 or on the tightening seat 213 adjacent to the second tightening head 212; the above first camera 410 and the second camera 420 are arranged oppositely and the imaging directions are on the same straight line in space.

[0098] The first camera 410 and the second camera 420 can be coaxially embedded, such as integrating a micro industrial camera inside the screwing head or symmetrically externally mounted, ensuring that the optical axes of the two cameras are collinear and coincide with the axis of the bolt, establishing a spatial pose reference line. Here, a ring structured light can be integrated around the camera to project a coded pattern onto the bolt end face, enhancing the texture information of the nut / screw through feature points (such as hexagonal corners or thread profiles). For example, using a high-precision calibration board (checkerboard / concentric circles) to appear in the fields of view of both cameras simultaneously can ensure feature extraction in low-contrast environments.

[0099] After the first camera 410 captures the nut image, it extracts the hexagonal contour based on Canny edge detection, locates the center of the circle through Hough transform, and establishes a local coordinate system using SIFT feature descriptors.

[0100] The second camera 420 analyzes the thread inclination angle in combination with the current structured light stripe technology, aligns the feature points of the two views through regional correlation matching, generates a disparity map and calculates the depth information. Based on the Zhang calibration method, the coordinate systems of the two cameras are mapped to the global coordinate system, and the lens distortion is eliminated using the homography matrix.

[0101] In this solution, the bolt axis equation can be calculated based on the three-dimensional coordinates of the nut center (X1, Y1, Z1) and the center of the bolt end face (X2, Y2, Z2), and the path parameters for the screwing head to move along the axis are generated;

[0102] where the displacement ΔL = [(X₂−X₁)²+(Y₂−Y₁)²+(Z₂−Z₁)²] , and the inclination angle θ = arctan[(Z2 - Z1) / ΔL]).

[0103] The two cameras synchronously scan the target area, quickly lock the approximate position of the bolt based on template matching, and trigger the tightening frame 210 to move to the preset station. The first camera 410 extracts the center of the nut, analyzes the plane normal vector in combination with the structured light stripe, and calculates the nut end pose (yaw angle α, pitch angle β). The second camera 420 uses the region growing algorithm to segment the thread area and fits the direction of the screw axis by the least squares method. The control unit receives the pose data from both ends, adjusts the position of the screwing head until the optical axes of the two cameras coincide with the actual axis of the bolt (error < ±0.2 mm), completing the centering. If the centering time exceeds the threshold or the error is too large, it is determined that there is a bolt skew situation, and a warning message is issued and the coordinate position of the bolt is calibrated.

[0104] This camera can transmit the image to the industrial control computer through the GigEVision protocol. After being processed by the vision algorithm, motion commands are generated and sent to the servo driver via the EtherCAT bus.

[0105] The human - machine interaction interface configured for the camera - corresponding terminal can develop a visual control panel based on ROS (Robot Operating System) to display the bolt pose, tightening torque curve, and abnormal alarm information in real - time. Deploy the lightweight YOLOv5s - T network on the embedded GPU.

[0106] Example 14:

[0107] On the basis of the above - mentioned embodiment, two ultrasonic rangefinders 500 are provided on the tightening frame 210 (a total of four, two on each side). The two ultrasonic rangefinders 500 are arranged with their orientations parallel; the ultrasonic rangefinders 500 located on both sides of the steel box girder are arranged facing each other; the measuring direction of the ultrasonic rangefinder 500 is parallel to the telescopic direction of the first screwing head 211 or the second screwing head 212. The core function of the ultrasonic rangefinder 500 is to dynamically calibrate the parallelism between the translation direction of the tightening frame 210 and the steel box girder plate surface through bilateral distance synchronous detection. Specifically, the two ultrasonic rangefinders 500 are installed facing each other on the tightening frames 210 on both sides of the steel box girder, and their measuring directions are strictly parallel to the telescopic direction (Z - axis) of the screwing head. By measuring the distance difference (ΔS = |S1 - S2|) between the two sides of the rangefinders to the steel box girder plate surface in real - time, where S1 is the real - time measured distance from the ultrasonic rangefinder 500 installed on one side of the steel box girder to the plate surface of this side, and S2 is the real - time measured distance from the ultrasonic rangefinder 500 installed on the other side of the steel box girder to the plate surface of the opposite side. Determine whether the moving direction of the tightening frame 210 is consistent with the normal direction of the plate surface: If ΔS exceeds the preset threshold, it indicates that the tightening frame 210 is inclined or offset from the steel box girder plate surface. At this time, the control unit can immediately adjust the driving parameters of the multi - axis bracket 120 (such as X / Y - axis compensation movement or Z - axis lifting correction) to ensure that the first screwing head 211 and the second screwing head 212 are always centered with the bolt axis during the screwing process, or perform manual intervention according to the feedback warning information to verify whether it is a sudden change in the parallelism of the steel box girder plate surface or an offset of the tightening frame 210, thereby eliminating the risk of tightening failure caused by uneven plate surface or installation deviation.

[0108] Example 15:

[0109] Based on the above embodiments, an electromagnetic suction seat 600 is provided on the multi-axis bracket 120 or the moving part 110. The electromagnetic suction seat 600 is connected to the control unit and is used to perform opening and closing operations on the electromagnetic suction seat 600 according to the instructions received by the control unit. In this way, the rapid switching of the adsorption state can be realized through the control unit instructions, providing stable connection and positioning switching for the multi-axis bracket 120 or the moving part 110. Specifically, the electromagnetic suction seat 600 is integrated at the bottom of the multi-axis bracket 120 or the moving part 110. After receiving the operation instruction through the control unit, the electromagnet is triggered to conduct and cut off the power: when powered on, the electromagnetic suction seat 600 generates a strong magnetic field to adsorb on the surface of the steel box girder top plate, forming an adsorption force to ensure the rigid fixation of the equipment and the workpiece during the processing; when powered off, the magnetic field disappears and the adsorption force is released, facilitating the rapid transfer of the equipment to the working position. By precisely controlling the on and off of the current, the instantaneous establishment and elimination of the adsorption force are realized, avoiding the positioning time-consuming problem of traditional mechanical clamps.

[0110] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed claims.

Claims

1. Symmetrical gantry-type multi-axis moving structure, characterized in that, The multi-axis moving structure is arranged on a high-strength bolt automatic tightening machine for tightening high-strength bolts on a steel box beam, and the multi-axis moving structure comprises: A moving part, used to enable the multi-axis moving structure as a whole to move on the top plate of the steel box beam; A main beam, which is arranged on the moving part; A vertical frame, which is movably arranged on the crossbeam; The vertical frame comprises: A secondary crossbeam, the secondary crossbeam is movably arranged on the main crossbeam, and is used to selectively move along the length direction of the main crossbeam; The door frame includes lifting shafts which are vertically movably connected to the two ends of the secondary crossbeam. The upper ends of the two lifting shafts are connected by connecting rods to form a door frame structure. The lower ends of the two lifting shafts are respectively provided with two screw heads which are mirror-symmetrical with respect to the central axis of the door frame. The two screw heads are respectively used for connecting the screws and nuts.

2. The symmetrical gantry type multi-axis moving structure according to claim 1 is characterized in that: Both ends of the secondary crossbeam are provided with lifting supports, and the lifting support sleeves are provided on the lifting shaft; The lifting shaft is provided with a first guide rail extending along the length direction of the lifting shaft, and the lifting support is provided with a lifting slide seat adapted to the first guide rail; The lifting shaft is provided with a first rack extending along the length direction of the lifting shaft, and the lifting support is provided with a first motor and a first gear. The first gear is meshed with the first rack and is rotatably connected to the lifting support. The first motor is connected to the rotating shaft of the first gear for driving the lifting shaft to perform lifting motion on the secondary beam when the first gear rotates.

3. The symmetrical gantry type multi-axis moving structure according to claim 2 is characterized in that: There are at least two first guide rails, and at least two first guide rails are arranged on the inner side of the door frame; The first gear is sleeved on the main shaft of the first motor and arranged in the gap between the lifting support and the lifting shaft.

4. The symmetrical gantry type multi-axis moving structure according to claim 1, characterized in that: The middle section of the secondary crossbeam is movably sleeved on the main crossbeam; The main crossbeam is provided with a second guide rail extending along the length direction of the main crossbeam, and the middle section of the secondary crossbeam is provided with a transverse sliding seat adapted to the second guide rail; The main crossbeam is provided with a second rack extending along the length direction of the main crossbeam, and the secondary crossbeam is provided with a second motor and a second gear. The second gear is meshed with the second rack and is rotatably connected to the secondary crossbeam. The second motor is connected to the rotating shaft of the second gear for driving the secondary crossbeam to make lateral movement on the main crossbeam when the second gear rotates.

5. The symmetrical gantry type multi-axis moving structure according to claim 4, characterized in that: The second guide rail and the second rack are both arranged on the upper plate surface of the main crossbeam; The second gear is mounted on the main shaft of the second motor and arranged in the gap between the middle sections of the main beam and the secondary beam, or the second gear is rotatably connected to the secondary beam through a central shaft and is located in the gap between the middle sections of the main beam and the secondary beam, and the second motor is connected to the central shaft through a transmission box arranged on the outside of the secondary beam.

6. The symmetrical gantry type multi-axis moving structure according to claim 1, characterized in that: The main crossbeam is provided with two photoelectric limit switches located on both sides of the vertical frame, which are used to respectively detect the distance between the auxiliary crossbeam and the two photoelectric limit switches.

7. The symmetrical gantry type multi-axis moving structure according to claim 1, characterized in that: It also includes a tightening assembly, which is movably arranged on the vertical frame; the tightening assembly includes a tightening frame connected to the inner side of the portal frame, a first screw head and a second screw head arranged on the tightening frame, and the first screw head and the second screw head are respectively used for docking or clamping high-strength bolts and nuts on the steel box girder, so as to drive the high-strength bolts to rotate according to the power unit configured according to the tightening assembly.

8. The symmetrical gantry type multi-axis moving structure according to claim 7, characterized in that: The tightening frame comprises: A tightening seat, the tightening seat is used to support the second screw head or the first screw head; A linear module, wherein the tightening seat is arranged on the linear module and is used for selectively moving on the linear module; A torque sensor is arranged on the tightening seat, and the torque sensor is connected to the second screwing head for collecting torque data of the second screwing head; the torque sensor is connected to a control unit, and the control unit is used to receive the dynamic signal of the torque sensor in real time and adjust the output parameters.

9. The symmetrical gantry type multi-axis moving structure according to claim 8, characterized in that: The tightening frame also includes a fixing plate, which is connected to the lower section of the lifting shaft and is located inside the door frame; The linear module is arranged on a side plate surface of the fixing plate away from the lifting shaft.

10. The symmetrical gantry type multi-axis moving structure according to claim 9, characterized in that: The tightening assembly also includes an electric push cylinder, the cylinder body of which is connected to or abuts against the fixing plate; The tightening seat comprises: A support seat, on which a third guide rail is provided, the extension direction of which is parallel to the direction of the lead screw of the electric push cylinder; A screw head seat, which is arranged on the third guide rail and connected to the screw rod of the electric push cylinder, is used to push / pull back the screw head seat when the electric push cylinder is started; the first screw head or the second screw head is arranged on the screw head seat.

Images