CN111674483B

CN111674483B - Magnetic-attraction wall-climbing robot for large-curvature surface spraying and working mode

Info

Publication number: CN111674483B
Application number: CN202010498937.1A
Authority: CN
Inventors: 王运龙; 管官; 金超光; 陈明; 秦品乐
Original assignee: Dalian University of Technology
Current assignee: Dalian University of Technology
Priority date: 2020-06-04
Filing date: 2020-06-04
Publication date: 2022-08-16
Anticipated expiration: 2040-06-04
Also published as: CN111674483A

Abstract

The utility model provides a wall climbing robot is inhaled with magnetism to large curvature surface spraying and working method, it belongs to wall climbing robot technical field. The robot is provided with wheels capable of rotating around a vertical shaft, so that the advancing direction of the wheels can be conveniently converted, and the universal translation function is realized; carrying out paint spraying operation on the working surface with large curvature by using a paint spraying system. When the robot works, the body can easily change the direction without turning around, the robot can well adapt to the working environment with a curved surface structure, and particularly, the design of integrating wheels and magnets enables the robot to still work normally on a large-curvature surface; the installed high-magnetic U-shaped permanent magnet can be stably adsorbed on the surface of a steel object without adjusting the height of the magnet in the movement process; the wheel type movement mechanism enables the robot to move flexibly; the carried paint spraying system can be used for performing the spraying work on the surfaces of the ship body and the large storage tank, greatly improving the working efficiency of the robot and reducing the burden of related workers.

Description

Magnetic-attraction wall-climbing robot for large-curvature surface spraying and working mode

Technical Field

The invention relates to a magnetic wall-climbing robot for large-curvature surface spraying and a working mode, and belongs to the technical field of wall-climbing robots.

Background

A robot is a machine device that can automatically perform a task. The system can not only accept the remote control command of human, but also automatically run the pre-programmed program, or take action according to the rules established by artificial intelligence technology. The task of the device is to assist or replace human work, and the device is generally applied to the production and manufacturing industry, the building industry or high-risk occupations. Since the research and development of the wall climbing robot has wide prospects and good social benefits in industry, the development of the wall climbing robot is very rapid since the research of the aspect is first developed in japan in the 60 th 20 th century, and the research of the wall climbing robot is developed in many countries in the world today. At present, many working environments are curved surface structures, such as the surfaces of large storage tanks or ship bodies, and many are large-curvature surfaces, so that problems of inflexible steering, insensitive movement, friction between a robot body and the curved surfaces and the like can occur when a wall-climbing robot moves due to the curved surfaces, and the working efficiency of the robot is easily influenced; when paint spraying operation is carried out on the curved surface, the robot is required to move in a specific non-spraying area, and the paint surface cannot be damaged; moreover, the size of the turning radius of the robot affects the operation precision and the operation quality, so that a wall-climbing robot which is flexible in steering and can adapt to a large-curvature working environment is needed. Disclosure of Invention

Aiming at the defects, the invention designs the magnetic wall-climbing robot for surface spraying with large curvature and a working mode, and aims to ensure that the wall-climbing robot can flexibly turn and translate when working on a curved surface, the spraying direction can be changed without turning during spraying, the working efficiency of the robot is improved, and the burden of workers is reduced.

The invention is realized by the following technical scheme: a magnetic attraction wall-climbing robot for large-curvature surface spraying comprises a body frame, a magnetic attraction system, a motion steering system and a spraying system.

The fuselage frame adopts four outer tubes to connect into the quadrangle support body through four square pipe upper beams and four square pipe underbeams, and square pipe upper beams connects the upside at the outer tube, and square pipe underbeams connects the downside at the outer tube.

The motion steering system adopts a wheel corner motor to be fixed on an upper beam of the square tube, and a pinion driven by the wheel corner motor is meshed with a bull gear fixed at the upper end of the hollow shaft; the hollow shaft is arranged in the outer pipe through an upper end bearing and a lower end bearing, the lower end of the hollow shaft is fixedly connected with a wheel seat, the wheel seat is fixedly connected with the upper ends of two wheel clamping plates provided with through grooves, the lower ends of the two wheel clamping plates support a wheel shaft driven by a wheel motor through the bearings, the wheel motor is fixedly connected with one of the wheel clamping plates, and a wheel is fixedly connected with the wheel shaft.

The magnetic attraction system adopts a top disc to be fixed at the top of the hollow shaft, the demagnetizing handle is arranged above the top disc, a handle cam of the demagnetizing handle is connected with one end of the magnet lifting rod, the other end of the magnet lifting rod penetrates through the hollow shaft and the wheel seat and penetrates through soft iron blocks fixedly connected with the through grooves on the two wheel clamping plates, U-shaped permanent magnets are respectively fixedly connected with the left side and the right side of each soft iron block, and the U-shaped permanent magnets are arranged on the outer sides of the wheel clamping plates.

The paint spraying system is arranged on a working platform constructed by square tube lower beams, a steering engine guide rail, a gear guide rail and a motor guide rail are arranged between two opposite square tube lower beams, a servo steering engine connected with a sliding block is arranged on the steering engine guide rail, the front end of the servo steering engine drives a transmission gear through a steering engine shaft, a motor connected with the sliding block is arranged on the motor guide rail, the motor drives the gear through a motor shaft, and the gear is meshed with the gear guide rail; the servo steering gears and the gears are respectively connected to two sides of the outer sleeve, the servo steering gears are connected with the outer sleeve through sleeve rods, and the gears are connected with the outer sleeve through gear rods; the front end of the outer sleeve is provided with a rotary sleeve which is fixedly connected with a paint spraying pipe, and the paint spraying pipe is provided with a paint spraying pipe nozzle; a paint mist cover and a paint mist recovery pipe are arranged above the paint spraying pipe, and a vision sensor is fixed above the paint mist cover; the transmission gear is meshed with a fluted disc on the periphery of the rotating sleeve; the rear end of the outer sleeve is connected with a paint feeding hose, and the rear end of the paint mist recovery pipe is connected with a paint mist recovery hose.

And a handle cam base circle of the demagnetizing handle is always contacted with the upper surface of the top disc.

The upper end bearing and the lower end bearing adopt rolling bearings capable of bearing axial force.

A working mode of a magnetic wall-climbing robot for large-curvature surface spraying is as follows:

(a) and (3) motion steering: when the wheel corner motor runs, the pinion is driven to rotate; the small gear is meshed with the large gear, the large gear drives the hollow shaft to rotate, and the hollow shaft drives the wheel seat to rotate, so that the wheels are driven to turn, and the direction conversion of the wall climbing robot is realized; the wheel motor drives the wheel to perform translational motion;

(b) magnetic attraction and demagnetization: the demagnetizing handle controls the U-shaped permanent magnet to move up and down through the magnet lifting rod, and when the U-shaped permanent magnet moves down, the robot is attracted to the working surface of the steel plate and can turn and move horizontally on the surface of the steel plate; when the U-shaped permanent magnet moves upwards, the suction force is reduced, and the robot moves away from the working surface of the steel plate;

(c) painting operation: the whole paint spraying machine is driven by a motor to move along the axial direction of a paint spraying pipe to reciprocate, and excess paint mist is collected by a paint mist cover and is absorbed to the shore through a paint mist recovery hose to be reused; a visual sensor is arranged above the paint mist cover, and the spraying quality is monitored visually; the robot can establish a three-dimensional model of a working area according to sensor data, and has a positioning function, a spraying path optimizing function, a pre-coating demonstration function and a spraying effect detection function.

(d) In the working environment of a large-curvature curved surface steel plate, a wheel corner motor and a wheel motor are matched with each other to regulate and control wheels, the robot drives the wheels to move in a translation mode on the working surface of the steel plate through the wheel motor, the robot is driven to move in a steering mode in situ through the wheel corner motor at a path terminal, then a transmission gear is driven through a servo steering engine to drive a rotary sleeve and a paint spraying pipe to rotate concentrically, the direction of a spray nozzle of the paint spraying pipe is regulated and then the spray nozzle of the paint spraying pipe moves in a translation mode, the spray pipe moves in the preset working surface of the steel plate in a reciprocating mode, and the paint spraying pipe is withdrawn into a frame of a machine body.

The motor drives the gear to move on the gear guide rail to drive the whole paint spraying structure to move, so that the paint spraying pipe can spray paint in a reciprocating manner; the drive gear of servo steering wheel and the interlock of the gear groove in the rotatory sleeve outside, the servo steering wheel drives the pipe that sprays paint in rotatory sleeve and the sleeve and rotates jointly to change the spray nozzle and spray the contained angle oil paint fog recovery hose on surface and link to each other with the recovery unit on the bank, unnecessary oil paint fog is collected by the coating cloud cover, is inhaled to the bank through retrieving the hose and utilizes once more.

The invention has the beneficial effects that: compared with the existing robot wheel type movement mechanism, the robot is more flexible in steering, wheels can rotate around a vertical shaft at will, turning and translation of the trolley in any direction can be realized by keeping the trolley body still, in-situ steering is realized, and the movement performance of the robot is improved; the two U-shaped magnets are connected through the soft magnetic blocks to form a magnetic loop with the steel working surface, so that sufficient adsorption force can be provided for the robot, and the height of the magnets does not need to be adjusted in the moving process; the four-wheel motion system is adopted, and the wheel type motion carrier enables the robot to move flexibly and is suitable for operation on curved surfaces, particularly large-curvature surfaces; compared with the existing spraying robot, the spraying robot can change the spraying trend without steering, and the spraying angle of the spraying pipe is flexible and variable, so that the flexibility of spraying is improved; the paint spraying pipe and the outer sleeve form an integral structure, the paint spraying pipe reciprocates on the gear guide rail, the paint spraying pipe can spray in a reciprocating mode, the action range is changed from a point to a line, the spraying area is increased, and the spraying efficiency of the robot is improved.

Drawings

Fig. 1 is a schematic view of the general structure of a magnetic wall-climbing robot for surface spraying with large curvature.

Fig. 2 is a block diagram of a motion steering system.

Fig. 3 is a block diagram of a painting system.

FIG. 4 is a view showing the magnetic attraction state of the demagnetizing handle.

Fig. 5 is a view showing a demagnetizing state of the demagnetizing handle.

Fig. 6 is a schematic diagram of the motion track of the robot during operation.

Fig. 7 is a schematic view of the spray painting tube in a spray painting configuration rotated 45 deg..

Fig. 8 is a schematic view of a 135 deg. rotation of the spray painting tube in a spray painting configuration.

Fig. 9 is a schematic view showing an initial state of the painting structure.

Fig. 10 is a schematic view showing a state in which the painting structure reciprocates.

FIG. 11 is a schematic view showing a state where the painting structure is recovered.

In the figure: 1. a demagnetizing handle, 1a, a handle cam, 2, a pinion, 3, a gearwheel, 4, a wheel corner motor, 5, an outer tube, 6, a wheel seat 7, a first wheel clamping plate, 7a, a second wheel clamping plate, 8, a soft iron block, 9, a U-shaped permanent magnet block, 10, a wheel, 11, a wheel motor, 12, a square tube lower beam, 13, a square tube upper beam, 14, an upper end bearing, 15, a hollow shaft, 16, a magnet lifting rod, 17, a lower end bearing, 18, a wheel shaft, 19, a top disc, 20, a steering engine guide rail, 21, a gear guide rail, 22, a motor guide rail, 23, an outer sleeve, 23a, a sleeve rod, 24, a gear, 24a gear rod, 25, a motor, 25a, a motor shaft, 26, a servo engine, 26a, a steering engine shaft, 27, a transmission gear, 28, a rotating sleeve, 29, a paint spraying pipe, 30, a paint mist cover, 31, a paint mist recovery pipe, 32 and a visual sensor, 33. paint mist recycling hose 34, paint supply hose 35, spray painting pipe nozzle 3001, paint mist recycling device 3002, paint supply device 3003 and ship surface.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings and implementation methods, and the described embodiments are only a part of embodiments of the present invention, rather than all embodiments, and all other embodiments obtained by those skilled in the art without any inventive work based on the embodiments of the present invention belong to the protection scope of the present invention.

The motion problem of the wall climbing robot needs to be considered particularly due to the irregularity of the curved surface working environment, particularly the steering motion of the robot, the gear train structure of the robot can easily realize the steering and translation motion of the robot, and at the moment, the robot body can be kept still. When the robot is placed on the working surface, the robot is adsorbed on the working surface and starts working.

Referring to fig. 1, 2 and 3, the universal translational magnetic attraction wall-climbing robot for spraying a large-curvature curved surface structurally comprises a body frame, an adsorption system, a motion steering system and a spraying system. In the frame of the fuselage, the outer tube 5 is positioned between the top plate 19 and the wheel seat 6, and the wheel seat 6 is positioned at the lower end of the outer tube 5; four square pipe upper beams 13 are connected at the 5 upside of outer tube, and four underbeams 12 are connected at 5 downside of outer tube, and the platform that four underbeams constitute can be used for carrying on paint finishing, and four upper beams can be used for carrying on wheel corner motor, and eight roof beam system structures constitute the overall framework of robot jointly, and upper and lower roof beam all adopts rust-resistant aluminum alloy material to process and forms.

In the motion steering system, a wheel motor 11 drives a wheel 10 through a wheel shaft 18; the wheel shaft 18 is positioned at one side of the wheel; the upper ends of the first wheel clamping plate 7 and the second wheel clamping plate 7a are welded on the wheel seat 6, and the lower ends are positioned on the side surface of the wheel 10 and used for fixing the wheel 10; the wheel 10 is a motion mechanism carrier of the robot; the wheel corner motor 4 is arranged on the square pipe upper beam 13, and a gear pair consisting of the pinion 2 and the bull gear 3 is connected with the wheel corner motor 4 and the hollow shaft 15; the upper end bearing 14 and the lower end bearing 17 are positioned between the outer tube 5 and the hollow shaft 15, and the rolling bearings capable of bearing axial force are adopted, so that the axial displacement of the outer tube and the hollow shaft can be limited, the upper and lower movement cannot be realized, and only the rotation can be realized; the upper end of the hollow shaft 15 is connected with the top disc 19, the lower end of the hollow shaft is connected with the wheel seat 6, when the wheel corner motor 4 runs, the gear can drive the hollow shaft 15 to rotate for 360 degrees, the hollow shaft 15 drives the wheel seat 6 to rotate, so that the wheels 10 are driven to turn, and the wall climbing robot can flexibly change the advancing direction to realize the function of universal translation.

In the magnetic suction system, the left end and the right end of a soft iron block 8 are respectively connected with two U-shaped permanent magnets 9, and the lower end of a magnet lifting rod 16 is connected with the soft iron block 8 which penetrates through grooves on two wheel clamping plates; the upper end is connected with a demagnetizing handle 1, and a handle cam 1a of the demagnetizing handle 1 is always contacted with the upper surface of the top plate 19. Four top plates 19 are fixed on the hollow shaft, and the lower ends of the four top plates are connected with the outer pipe; and (3) demagnetizing function design of an adsorption system: the demagnetizing handle 1 can control the U-shaped permanent magnet 9 to move up and down through the magnet lifting rod 16, and the trolley is attracted to the surface of the steel plate when moving down; when moving upwards, the suction force is reduced, and the trolley can be separated from the working surface of the steel plate. The adsorption module of the adsorption system adopts the U-shaped permanent magnet 9, so that sufficient adsorption force can be provided.

The paint spraying system is arranged on a working platform constructed by square tube lower beams 12, a steering engine guide rail 20, a gear guide rail 21 and a motor guide rail 22 are arranged between two opposite square tube lower beams 12, a servo steering engine 26 connected with a sliding block is arranged on the steering engine guide rail 20, the front end of the servo steering engine 26 drives a transmission gear 27 through a steering engine shaft 26a, a motor 25 connected with a sliding block is arranged on the motor guide rail 22, the motor 25 drives a gear 24 through a motor shaft 25a, and the gear 24 is meshed with the gear guide rail 21; the servo steering gear 26 and the gear 24 are respectively connected to two sides of the outer sleeve 23, the servo steering gear 26 is connected with the outer sleeve 23 through a sleeve rod 23a, and the gear 24 is connected with the outer sleeve 23 through a gear rod 24 a; the front end of the outer sleeve 23 is provided with a rotating sleeve 28, the rotating sleeve 28 is fixedly connected with a paint spraying pipe 29, and the paint spraying pipe 29 is provided with a paint spraying pipe nozzle 35; a paint mist cover 30 and a paint mist recovery pipe 31 are arranged above the paint spraying pipe 29; the transmission gear 27 is meshed with a fluted disc on the periphery of the rotating sleeve 28; the rear end of the outer sleeve 23 is connected to a paint supply hose 34, and the rear end of the paint mist recovery pipe 31 is connected to a paint mist recovery hose 33. The outer sleeve 23 cannot be rotated, and the servo steering engine 26 can drive the rotating sleeve 28 to rotate through the transmission gear 27, so that the paint spraying pipe 29 rotates concentrically; the outer sleeve 23, the gear 24, the motor 25, the servo steering engine 26, the transmission gear 27, the rotating sleeve 28 and the paint spraying pipe 29 are fixedly connected to form an integral paint spraying structure, and the whole paint spraying body can move along the axial direction of the paint spraying pipe and can reciprocate under the driving of the motor 25. A visual sensor 32 is arranged above the paint mist cover 30, and the spraying quality can be monitored visually.

Referring to fig. 4 and 5, the demagnetizing handle 1 has two working states, fig. 4 is a magnetic attracting state, a distance between a connection position of the magnet lifting rod and the demagnetizing handle and the top disk is h, and at this time, the high-magnetic U-shaped permanent magnet blocks are very close to the working surface, and the robot is attracted to the high-magnetic U-shaped permanent magnet blocks; fig. 5 shows the demagnetizing state, the distance between the connection position of the magnet lifting rod and the demagnetizing handle and the top disk is H (H > H), at this time, the demagnetizing handle is pulled flat, the magnet lifting rod is lifted, the high-magnetic U-shaped permanent magnet blocks are far away from the working surface, and the robot can be separated from the working surface.

Referring to fig. 6, a simple schematic diagram of a motion track of a robot during painting is shown, wheels are installed at positions i, ii, iii and iv of the robot, and the robot is connected with a paint mist recycling device 3001 and a paint feeding device 3002 to work on a ship surface 3003. The robot moves from the position A to the position B, the body does not need to turn around at the position B, the wheels do steering, only do translational motion, the robot can move from the position B to the position C, the wheels do steering at the position C, the robot can move from the position C to the position D, and the robot can complete curved surface motion by reciprocating motion; the steering angle of the wheels is different by comprehensively controlling the steering motors of the four sets of motion systems, so that the motion in any direction can be realized. In addition, when the robot moves to the position C at the position B, the paint spraying pipe rotates, and the paint spraying angle of the nozzle is changed to adapt to the new spraying trend of the robot.

Figures 7 and 8 show a rotational view of the spray painting tube. The servo motor 26 is driven by a transmission gear 27 to drive the rotary sleeve 28 and the paint spraying pipe 29 to rotate, so that the jet angle of the nozzle of the paint spraying pipe is changed. The nozzle of fig. 7 included a 45 deg. angle with the work surface and after rotation, the nozzle of fig. 8 included a 135 deg. angle with the work surface.

Referring to fig. 9, 10 and 11: when the spraying work is carried out, the motor 25 drives the paint spraying structure to move from the position shown in the figure 9 to the position shown in the figure 10, and then from the position shown in the figure 11 to the position shown in the figure 9, and the reciprocating motion of the paint spraying structure is formed by repeating the actions; and after the robot reaches the position E to finish the spraying task, the motor drives the paint spraying structure to move to the position shown in the figure 11, partial structure of the paint spraying structure is retracted into the frame of the wall climbing robot, and the spraying work is finished.

The working principle is as follows: when the robot is placed on a working surface, the demagnetizing handle is in a magnetic attraction state, the high-magnetic U-shaped permanent magnet blocks are close to the curved surface, the robot is adsorbed on the working surface, and the robot can start to work at the moment. Starting a wheel motor, and driving wheels to move forward by the motor; the wheel corner motor is started, the rotary driving force is transmitted to the hollow shaft through the gear pair, the hollow shaft is connected with the wheel seat, the wheels are connected with the wheel seat through the wheel baffle, when the hollow shaft rotates, the wheels also rotate along with the hollow shaft, the two motors are mutually matched to regulate and control the wheels, the robot can easily move and turn on the working surface, the robot body is not moved, the robot can freely turn and walk in situ, a series of actions are completed, and after the paint spraying functional module is carried, corresponding curved surface spraying operation can be carried out.

When the robot finishes the planned spraying task, the demagnetizing handle is pressed down and is in a demagnetizing state, the magnet lifting rod is lifted, the high-magnetic U-shaped permanent magnet blocks are far away from the working surface, the robot is separated from the surface of the ship body at the moment and can be recovered, and the work is finished.

The robot adopts a four-wheel motion system, and the wheels and the magnets are integrated into a whole, so that the working environment of a large-curvature curved surface can be better met; the two motors are mutually matched to regulate and control the wheels, the robot can easily do translational motion on the working surface without turning around, and the robot body is not moved, so that the robot can realize the in-situ arbitrary steering and translation and complete a series of actions; in actual work, the robot firstly makes translational motion, the robot makes steering motion at the path terminal, and then makes translational motion, and the robot can finish the motion on a preset working surface by reciprocating motion in such a way, and the walking path of the robot is the surface which is already worked, so that the robot is not influenced by the surrounding environment, and the motion stability of the robot is ensured.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and modifications of the invention can be made, and equivalents of some features of the invention can be substituted, and all changes that come within the spirit and scope of the invention are intended to be embraced therein.

Claims

1. A magnetic attraction wall-climbing robot for large-curvature surface spraying comprises: the painting system comprises a machine body frame, a motion steering system, a magnetic suction system and a painting system, and is characterized in that the machine body frame is formed by connecting four outer tubes (5) into a quadrilateral frame body through four square tube upper beams (13) and four square tube lower beams (12), the square tube upper beams (13) are connected to the upper side of the outer tubes (5), and the square tube lower beams (12) are connected to the lower side of the outer tubes (5); the outer pipe (5) is positioned between the top disc (19) and the wheel seat (6); the motion steering system adopts a wheel corner motor (4) fixed on an upper beam (13) of a square tube, and a pinion (2) driven by the wheel corner motor (4) is meshed with a bull gear (3) fixed at the upper end of a hollow shaft (15); the hollow shaft (15) is arranged in the outer tube (5) through an upper end bearing (14) and a lower end bearing (17), the lower end of the hollow shaft (15) is fixedly connected with a wheel seat (6), the wheel seat (6) is fixedly connected with the upper ends of two wheel clamping plates provided with through grooves, the lower ends of the two wheel clamping plates support a wheel shaft (18) driven by a wheel motor (11) through the bearings, the wheel motor (11) is fixedly connected with one wheel clamping plate, and a wheel (10) is fixedly connected with the wheel shaft (18); the upper end of the wheel clamping plate is welded on the wheel seat (6), and the lower end of the wheel clamping plate is positioned on the side surface of the wheel (10) and used for fixing the wheel (10); the magnetic attraction system is characterized in that a top disc (19) is fixed at the top of a hollow shaft (15), a demagnetizing handle (1) is arranged above the top disc (19), a handle cam (1 a) of the demagnetizing handle (1) is connected with one end of a magnet lifting rod (16), the other end of the magnet lifting rod (16) penetrates through the hollow shaft (15) and a wheel seat (6) to be fixedly connected with soft iron blocks (8) penetrating through grooves in two wheel clamping plates, the left side and the right side of each soft iron block (8) are fixedly connected with a U-shaped permanent magnet (9), and the U-shaped permanent magnets (9) are arranged on the outer sides of the wheel clamping plates; the paint spraying system is arranged on a working platform constructed by square tube lower beams (12), a steering engine guide rail (20), a gear guide rail (21) and a motor guide rail (22) are arranged between two opposite square tube lower beams (12), a servo steering engine (26) connected with a sliding block is arranged on the steering engine guide rail (20), the front end of the servo steering engine (26) drives a transmission gear (27) through a steering engine shaft (26 a), a motor (25) in sliding connection is arranged on the motor guide rail (22), the motor (25) drives a gear (24) through a motor shaft (25 a), and the gear (24) is meshed with the gear guide rail (21); the servo steering engine (26) and the gear (24) are respectively connected to two sides of the outer sleeve (23), the servo steering engine (26) is connected with the outer sleeve (23) through a sleeve rod (23 a), and the gear (24) is connected with the outer sleeve (23) through a gear rod (24 a); a rotary sleeve (28) is arranged in the front end of the outer sleeve (23), the rotary sleeve (28) is fixedly connected with a paint spraying pipe (29), and a paint spraying pipe nozzle (35) is arranged on the paint spraying pipe (29); a paint mist cover (30) and a paint mist recovery pipe (31) are arranged above the paint spraying pipe (29), and a visual sensor (32) is fixed above the paint mist cover (30); the transmission gear (27) is meshed with a fluted disc on the outer side of the rotating sleeve (28); the rear end of the outer sleeve (23) is connected with a paint supply hose (34), and the rear end of the paint mist recovery pipe (31) is connected with a paint mist recovery hose (33);

the base circle of a handle cam of the demagnetizing handle (1) is always contacted with the upper surface of the top disc (19); the upper end bearing (14) and the lower end bearing (17) adopt rolling bearings capable of bearing axial force.

2. The working mode of the magnetic wall-climbing robot for spraying the large-curvature surface according to claim 1, which is characterized in that:

(a) and (3) motion steering: when the wheel corner motor (4) runs, the pinion (2) is driven to rotate; the small gear (2) is meshed with the large gear (3), the large gear (3) drives the hollow shaft (15) to rotate, and the hollow shaft (15) drives the wheel seat (6) to rotate, so that the wheels (10) are driven to turn, and the direction conversion of the wall-climbing robot is realized; the wheel motor (11) drives the wheel (10) to perform translational motion;

(b) magnetic attraction and demagnetization: the demagnetizing handle (1) controls the U-shaped permanent magnet (9) to move up and down through the magnet lifting rod (16), and when the U-shaped permanent magnet (9) moves down, the robot is attracted to the working surface of the steel plate and can turn and translate on the surface of the steel plate; when the U-shaped permanent magnet (9) moves upwards, the suction force is reduced, and the robot moves away from the working surface of the steel plate;

(c) painting operation: the whole paint spraying structure moves along the axial direction of a paint spraying pipe (29) under the drive of a motor (25) to do reciprocating motion, and excess paint mist is collected by a paint mist cover (30) and is sucked to the shore through a paint mist recovery hose (33) for reuse; a visual sensor (32) is arranged above the paint mist cover (30), and the spraying quality is monitored visually;

(d) in the working environment of a large-curvature curved surface steel plate, a wheel corner motor (4) and a wheel motor (11) are matched with each other to regulate and control a wheel (10), the robot drives the wheel to move in a translation mode on the working surface of the steel plate through the wheel motor (11), the robot is driven to move in a steering mode on site through the wheel corner motor (4) at a path terminal, then a transmission gear (27) is driven through a servo steering engine (26), a rotary sleeve (28) and a paint spraying pipe (29) are driven to rotate concentrically, a paint spraying pipe nozzle (35) is rotated and then moved in a translation mode, the reciprocating motion is carried out, the movement on the preset working surface of the steel plate is completed, and the paint spraying pipe (29) is retracted into a machine body frame.