Vacuum suction cup type wall-climbing welding robot

Abstract

The vacuum suction cup type wall-climbing welding robot comprises a vehicle body structure, a positioning module, a pose monitoring module, a driving module, a welding module and a control system. The positioning module adopts a laser displacement sensor and a depth camera which are respectively fixed on a welding head and a vehicle body; the pose monitoring module is a vehicle body built-in gyroscope; the driving module comprises a group of driving wheels and a driving motor in a driving box body; the adsorption module is composed of two sets of adsorption wheels, each adsorption wheel is of a capsule structure, in other words, the middle portion is composed of an adsorption shaft and suction cups, the suction cups are distributed on the shaft face in a spiral line mode, and an air inlet valve and an air release valve are arranged on the two sides of the adsorption shaft respectively. The welding robot is suitable for a multi-diameter smooth weak magnetic thin-wall surface, and complete self-walking welding can be achieved; meanwhile, the robot can achieve accurate recognition and positioning of the welding gun on the welding seam, and welding work of the multi-diameter weak magnetic tank can be efficiently completed.

Description

Technical field:

[0001] The invention belongs to the field of welding robots, in particular to a vacuum suction cup type wall climbing welding robot. Background technology:

[0002] Welding robots have a wide range of application backgrounds and application value in device processing in the fields of engineering, medical treatment, aerospace, etc. At present, the working modes of welding robots are mainly divided into orbital welding, permanent magnetic adsorption climbing welding, and suction cup climbing welding.

[0003] Track welding robots require manual configuration of tracks, which is very time-consuming and laborious to operate during the welding of large-diameter tanks. For example, a magnetically movable track-type pipeline welding robot with publication number CN116900585B adjusts the track chain to match the support wheel with the welding pipeline, and adjusts the magnetic wheel to absorb the wall to provide the robot with absorption force. The chain needs to be disassembled and adjusted before and after welding. At the same time, the magnetic wheel and support wheel cannot guarantee the firmness of the robot's own weight on the thinner pipe wall.

[0004] The permanent magnetic adsorption wall-climbing welding robot uses permanent magnetic wheels or permanent magnetic tracks to adsorb the welding wall surface and control the welding head to match the weld to complete the welding. For example, the permanent magnetic adsorption wheel-climbing crawling machine for welding robots with the publication number CN110386198A adopts a wheel-climbing drive system and embeds the permanent magnetic adsorption unit inside the crawlers on both sides. This can provide a large adsorption force, but there is a minimum radius requirement for the welding pipe wall, and it cannot adapt to most pipe wall radii. At the same time, the adsorption force of the permanent magnetic adsorption wall-climbing welding robot for weak magnetic materials is difficult to support itself, and the wheel-climbing structure will pause during the turning, which affects the continuity of welding.

[0005] The suction cup wall-climbing welding robot uses a vacuum suction cup to absorb the wall surface to provide the robot with suction force. However, due to the limited suction force of the suction cup, the robot's own weight and body size need to adapt to the suction capacity provided by the suction cup. At the same time, the welding robot arm must match the weld seam and complete the welding operation autonomously. The suction cup must frequently switch between the suction and deflation modes when the suction wheel rotates, requiring the air pump to start and stop continuously, reducing its service life. At the same time, the overall control difficulty of the robot is significantly increased.

[0006] At present, traditional welding robots such as orbital welding and permanent magnetic adsorption climbing welding are difficult to adapt to the continuous welding of weak magnetic large radius pipe walls due to their own structure and welding materials. In view of the existing problems, the present invention proposes a new application method. Summary of the invention:

[0007] In view of the problems existing in the above welding robots, the purpose of the present invention is to provide a vacuum suction cup wall-climbing welding robot, which is lighter than the permanent magnet wall-climbing robot and can complete welding work on most thin-walled tube sheets; the robot realizes wall adsorption and walking functions through the adsorption wheels and drive wheels connected to the chassis. The adsorption capacity is sufficient to support itself and walk without pause. Through the damping hinge, it can adapt to smooth wall welding of different types and diameters, and has a wide range of applications; the welding robot completes the body posture adjustment and welding head positioning through laser displacement sensors, depth vision cameras and built-in gyroscopes. The welding head cooperates with the wire feeder to complete the welding of the weld, providing an implementation plan that efficiently and accurately completes the welding of the entire tank body.

[0008] The purpose of the present invention is achieved through the following technical solutions:

[0009] A vacuum suction cup wall-climbing welding robot, characterized in that it includes a robot body structure, a positioning module, a posture monitoring module, a driving module, a welding module and a control system; the body structure includes an outer shell and a chassis, characterized in that the outer shell is in the shape of a rectangular box, the lower part of the shell cooperates with the bottom plate, and a touch display screen is installed on the top of the robot shell; the chassis includes a front bottom plate, a rear bottom plate, a driving wheel, an adsorption wheel and a driving box body; the front bottom plate and the rear bottom plate are hinged to each other by a damping hinge, which can complete rotation at any angle; the top of the driving box body is connected to the front bottom plate, and axial holes are symmetrically opened on both sides and a driving shaft sleeve is extended, and a driving motor is installed inside; the driving wheel is concentric with the axial hole and is limited by the driving shaft sleeve; the adsorption wheel is respectively connected to the adsorption wheel clamps of the front bottom plate and the rear bottom plate.

[0010] For further optimization, the positioning module includes a depth vision camera and a laser displacement sensor, which are fixed to the side of the shell by bolts. The laser displacement sensor, the depth vision camera, and the center of the robotic arm are on the same horizontal line to ensure the consistency of collected and received information.

[0011] For further optimization, the posture detection module includes a gyroscope built into the shell.

[0012] For further optimization, the welding module includes a robotic arm, a robotic arm forearm, a linear module and a welding gun sleeve, wherein the robotic arm is fixed to the side of the outer shell, the robotic arm forearm, the linear module and the robotic arm forearm are connected through a dual-axis servo, and the welding gun sleeve and the linear module are connected through a ground pin to ensure that the welding head and the robotic arm are perpendicular to each other.

[0013] For further optimization, the adsorption shaft is a capsule-shaped vacuum suction cup adsorption device, the side of the middle suction cup main shaft is connected to the suction valve, and the right side is connected to the exhaust valve; the suction valve is connected to the exhaust pipe, and the exhaust valve does not need to be connected to the pipe, and is directly connected to the outside world after the exhaust side air hood stabilizes the flow.

[0014] For further optimization, the diameter of the adsorption axis at the center of the adsorption wheel is smaller than the diameters of the air extraction plate and the air release plate, so as to prevent the shaking of the protruding part of the suction cup from interfering with the operation process of the robot.

[0015] Compared with the existing structure, the beneficial effects of the present invention are:

[0016] The present invention provides a vacuum suction cup wall-climbing welding robot, which comprises a foldable chassis, a welding mechanical arm, a welding head, a visual positioning system and a welding control system. The robot overcomes the limitation of the minimum working radius of traditional welding robots and can complete the welding of multi-diameter and multi-angle tanks; overcomes the problem of the robot being stuck due to friction and resistance during operation, solves the problem of most of the friction resistance of the adsorption wheel during the advancement while ensuring the stability of the robot during vacuum suction cup adsorption, and can flexibly adjust the welding posture to correct the welding angle deviation problem in time; the existing suction cup robot needs to continuously adjust the on and off of the air pump during the operation of the robot, and the control difficulty is high and cumbersome. By adjusting the structure of the traditional suction cup trolley, the control difficulty of the air pump is simplified and the adsorption capacity of the adsorption shaft is increased, ensuring that the vehicle body is fully capable of self-walking to complete the welding work when the rope is hoisted. Description of the drawings:

[0017] Figure 1 A schematic diagram of the three-dimensional structure of a vacuum suction cup wall-climbing welding robot provided by the present invention;

[0018] FIG2 is a schematic diagram of a housing assembly structure provided by the present invention; FIG2(a) is a front view of the housing; FIG2(b) is a rear view of the housing;

[0019] FIG3 is a schematic diagram of a bottom plate assembly structure provided by the present invention; FIG3(a) is a schematic diagram of the structure of the front and rear bottom plates combined together, FIG3(b) is a schematic diagram of the three-dimensional structure of the front bottom plate; FIG3(c) is a schematic diagram of the three-dimensional structure of the rear bottom plate;

[0020] FIG4 is a schematic diagram of the structure of a wall adsorption device provided by the present invention; FIG4(a) is a schematic diagram of the structure of the adsorption device when assembled; FIG4(b) is a schematic diagram of the structure of the adsorption device when disassembled;

[0021] Figure 5 A schematic diagram of a working state provided by the present invention;

[0022] Figure 6 This is the principle diagram of vacuum adsorption;

[0023] The annotations in the figure are as follows:

[0024] 1-shell, 2-rear bottom plate, 3-adsorption wheel, 4-front bottom plate,

[0025] 11-touch screen, 121-robotic arm, 122-robotic arm, 123-linear module, 124-welding gun sleeve, 13-laser displacement sensor, 141-camera support, 142-depth vision camera, 151-knob, 152-OLED display,

[0026] 16- drive line input port, 17- lifting ear,

[0027] 21-damping hinge, 41-driving wheel, 42-driving wheel suction cup, 43-driving box,

[0028] 44-drive shaft sleeve, 45-drive box bottom plate, 46-adsorption wheel snap ring,

[0029] 31- snap ring matching groove, 32- suction wheel suction cup,

[0030] 33-air hood, 34-air release plate, 35-air extraction plate, 36-adsorption shaft cover, 37-adsorption shaft. Specific implementation method:

[0031] The present invention is further explained below in conjunction with working examples and drawings, but this is not intended to limit the scope of protection of the present application.

[0032] The vacuum suction cup wall-climbing welding robot of the present invention comprises a base plate, a shell, a positioning device, a posture monitoring device, a driving device, an adsorption device, a welding execution device and a control system. The positioning device comprises a camera support 141 and a depth vision camera 142, which are respectively installed on the side of the shell 1;

[0033] The posture monitoring device includes a laser displacement sensor 13 and a gyroscope. The laser displacement sensor 13 is installed on the side of the housing 1 and the gyroscope is installed inside the housing. The posture of the robot can be monitored at any time and uploaded to the control system to adjust the drive motor in real time.

[0034] The welding execution device is a three-degree-of-freedom robot arm, including a robot arm 121, a robot arm 122, a linear module 123 and a welding gun sleeve 124, wherein the robot arm 121 is fixed to the side of the housing 1, the robot arm 122, the linear module 123 and the robot arm 122 are connected through a servo, and the welding gun sleeve 124 and the linear module 123 are connected through a foot. The robot arm can complete the welding work of a fan-shaped area with a radius of 15 to 25 cm with the vehicle body as the center;

[0035] The driving device is a front-wheel drive mechanism, in which the driving wheel 41 is limited by the sleeve 44, and the driving box 43 has built-in bearings and a driving motor, and the walking speed and posture of the robot can be adjusted according to the control system;

[0036] In the adsorption device, the adsorption shaft is limited by the center of two left and right clamping rings, and the baffle cover is connected by external threads. The clamping ring is respectively connected to the degassing plate and the air extraction plate by external threads, so as to realize the concentric rotation of the adsorption shaft relative to the degassing plate and the air extraction plate. The air pump is connected to the air cover on the side of the robot, and the air of the adsorption shaft is extracted from the reserved notch of the air extraction plate. At the same time, the baffle on the degassing plate prevents the air flow from escaping, thereby realizing the vacuum in the corresponding channel of the adsorption shaft, and the suction cup generates adsorption force. During the vacuum adsorption process, the power of the air pump mainly affects the adsorption force generated by the adsorption shaft. The greater the power, the better the adsorption effect, but it will increase the running resistance and generate greater energy consumption losses. The robot in this embodiment uses an air pump with an exhaust volume of 140L / min, which can meet the robot's smooth progress without generating high noise.

[0037] The control system includes an electric control device and a gyroscope inside the housing. The electric control device is composed of a driver, a control chip, a sensor serial port and related circuits. The control system can complete the end effector to weld matching according to the weld information of the depth camera and the laser displacement sensor, and at the same time receive the robot operation signal sent by the posture monitoring device to perform differential adjustment on the body posture;

[0038] Figure 1 The three-dimensional structure of a vacuum suction cup wall-climbing welding robot is illustrated, including a housing 1, a front bottom plate 4, a rear bottom plate 2, a suction wheel 3, a drive device and a control system. The bottom of the housing 1 is connected to the front bottom plate 4 by countersunk bolts; the drive device includes a drive wheel 41, a drive wheel suction cup 42, a drive shaft sleeve 44 and a drive box 43 with a built-in drive motor, as well as an electronic control device and a driver in the housing.

[0039] FIG2 is a schematic diagram of the structure of the housing assembly provided by the present invention, wherein the touch screen 11, the knob 151 and the OLED display are respectively fixed to the top and the front side of the housing 1 by bolts, forming a robot manual adjustment module. The air pump power, motor speed and welding gun power can be manually adjusted by adjusting the knob 151, and the robot parameters are displayed on the OLED display 152.

[0040] The camera support 141 is a plastic or metal shell, and the camera data cable is placed in the inner cavity of the shell; the camera support 141 is fixed to the side of the shell by bolts, and the depth vision camera 142 is fixed in the camera support 141 by a slot and bolts.

[0041] The laser displacement sensor 13 and the robot arm 121 are fixed to the side of the shell by bolts, and the center heights of the two are flush. The robot arm 121, the robot arm 122, and the linear module 123 are respectively connected to each other by a dual-axis servo, which can ensure that the robot arm can complete a 0-360° rotation within the working radius. Its working radius can be adjusted arbitrarily by replacing robot arms of different lengths; the linear module 123 and the welding gun sleeve 124 are connected by feet and bolts to match the height spacing between the welding gun and the weld.

[0042] The lifting lug 17 is fixed to the right side of the shell by welding to prevent the robot from falling off during operation; the drive line input port 16 is a boss hole formed by welding the sleeve and the shell, which is used for the interaction between the power supply of the electric control system inside the shell 1 and the communication line of the host computer.

[0043] Figure 3 is a structural schematic diagram of a base plate provided by the present invention, wherein the base plate includes a front base plate 4 and a rear base plate 2, wherein the front base plate 4 is connected to the rear base plate 2 via a damping hinge and can be folded 90° to 180°. The pipe diameter of the wall-climbing robot can be arbitrarily replaced and adjusted according to the length of the base plate.

[0044] The driving box 43 is fixed to the bottom of the front base plate 4 by bolts. The installation position can ensure that the center of the driving shaft sleeve 44 and the adjacent adsorption wheel clamp 46 are parallel to the front base plate 4 and the center-to-center distance is equal to the center-to-center distance of the adsorption wheel clamp 46 of the two base plates, so that the center of gravity of the robot is near the damping hinge 21; the driving shaft sleeve 44 is a truncated cone hole on the left and right sides of the driving box 43, which is used to limit the driving wheel 41 in the horizontal direction. The bearing seat and the driving motor are installed in the driving box 43, and their axis is concentric with the driving shaft sleeve 44 and fixed to the inner wall of the driving box 43; the adsorption shaft clamp 46 is connected to the bottom of the front base plate 4 and the rear base plate 2 by threads and is suspended under the base plate. There is a protrusion on the inner side of the clamp for embedding into the clamp matching groove 31 on the adsorption wheel 3 to limit the adsorption wheel 3 in the horizontal direction, and can also be used to fix the suction plate 34 or the air release plate 35.

[0045] FIG4 is a schematic diagram of the structure of an adsorption wheel provided by the present invention; the adsorption shaft 37 in the adsorption wheel 3 is placed at the center of the left and right adsorption shaft clamping rings 46, and is respectively connected to the adsorption shaft blocking cover 36 by threads on its side and right side, and a rubber pad corresponding to the hole position is installed on the inner side of the adsorption shaft blocking cover 36 to ensure air tightness; the adsorption wheel suction cup 32 is staggeredly distributed on the side wall of the adsorption shaft in a spiral shape, and the spiral structure can make the adsorption wheel suction cup 32 more compactly arranged to ensure the stability of the air pressure in the channel. In this embodiment, only a 6-airway adsorption shaft is shown, and any number of airways can be selected according to the shaft diameter; the degassing sheet 34 is connected to the side adsorption shaft clamping ring 4 by threads. 6 connection, the exhaust sheet 35 is connected to the right side adsorption shaft clamping ring 46 through a thread, the notch of the exhaust sheet 35 and the baffle of the air release sheet 34 are synchronized in position and are at the lowest point of the circumference when the thread is tightened, so that when the adsorption channel of the adsorption shaft turns to the wall, the notch of the exhaust sheet 35 opens the exhaust channel and the baffle of the air release sheet 34 closes the air release channel to maintain the vacuum environment in the adsorption channel; the air hood 33 is respectively connected to the exhaust sheet 35 and the air release sheet 34 by welding to form an exhaust valve and an air release valve, and the air hood 33, the exhaust sheet 35 and the air release sheet 34 have the same diameter, which can ensure the air tightness of the air chamber and stabilize the internal air pressure of the adsorption shaft 3.

[0046] From the perspective of the adsorption wheel 3 as a whole, the diameter of the adsorption shaft 37 is smaller than the exhaust plate 35 and the exhaust plate 34. This is to ensure that the position of the adsorption wheel suction cup 32 remains stable during adsorption and does not slide left and right due to the thickness of the suction cup during adsorption; at the same time, it makes it easier for the suction cup to detach from the wall.

[0047] Figure 5 The figure is a schematic diagram of a motion provided by the present invention. The working principle of the welding robot in the present invention is as follows: the bottom plate 4 and the bottom plate 2 are bent to the corresponding angle according to the required welding pipe radius and placed in the initial position, the lifting lug 17 is connected to the safety rope, and then the air pump evacuates the adsorption shaft 3, so that the internal vacuum of the adsorption wheel suction cup 32 close to the welding pipe is made, so that the robot is adsorbed on the wall of the welding pipe, and no adjustment is required from the start of the air pump until the robot completes the welding work. The left and right drive motors in the drive box 45 drive the drive wheel 41 to rotate through the driver instruction, and then drive the adsorption wheel 3 to rotate. The depth vision camera 142 and the laser displacement sensor 13 send the parameters to the control system, and then differentially adjust the robot posture of the drive wheel 41 for the robot to match the weld position. The robot arm 121, the robot arm 122, the linear module 123 and the welding sleeve 124 receive the weld coordinates of the control system to solve the spatial position of the welding head, and turn on the welding gun to complete the welding operation after the welding head matches the weld.

[0048] The adsorption principle of the adsorption wheel of the present invention is as follows:

[0049] Figure 6The side is an air extraction sheet 35, and the right side is an air release sheet 34. The solid line is the initial position of the airway, the dotted line is the position where the airway is about to leave the circular notch, and the fine dotted line is the position where the airway has left the notch.

[0050] The air pump evacuates the connected air extraction valve. At this time, the only channel to be evacuated is the airway corresponding to the solid line in the circular groove opened by the air extraction plate, and the corresponding airway is blocked at the position of the air release plate, which prevents external gas from flowing into the airway and maintains the vacuum environment inside the airway. When the adsorption shaft moves forward and rotates counterclockwise to the dotted line position, the airway is about to be pushed out of the circular groove, and the adjacent airway rotates into the circular groove. This stage is the adsorption transition stage. While ensuring the vacuum of the next airway, it prevents the airway from suddenly losing its adsorption capacity, resulting in a decrease in adsorption force and causing the trolley to fall off. When the adsorption shaft rotates to the fine dotted line position, it means that this airway is connected to the outside world. Even if the air pump evacuates, it will not affect the airway that is in the wall adsorption stage, ensuring the stability of the forward speed of the adsorption shaft and reducing the walking resistance.

[0051] After the air pump is turned on, the adsorption wheel can automatically switch the vacuum and release stages of the airway according to the robot's walking, without the need to switch the air pump.

[0052] In addition, the robot adopts a damping articulation mode for the front and rear bottom plates to ensure that the robot can adapt to welding work on different curved surfaces.

[0053] The present application achieves a good effect by automatically switching the air channel of the adsorption wheel and coordinating the diameter difference between the adsorption shaft and the air extraction plate and the air discharge plate to ensure the stable movement ability of the adsorption shaft on the smooth wall surface.

[0054] Any matters not described in the present invention are applicable to the prior art.

Claims

1. A vacuum suction cup wall climbing welding robot, comprising a robot body structure, a positioning module, a posture monitoring module, a driving module, a welding module and a control system, wherein the body structure comprises a shell (1) and a chassis, and is characterized in that: The shell is in the shape of a rectangular box, the bottom of the shell is matched with the bottom plate, and a touch display screen is installed on the top of the robot shell; the chassis includes a front bottom plate (4), a rear bottom plate (2), a driving wheel (41), an adsorption wheel (3) and a driving box (43); the front bottom plate (4) and the rear bottom plate (2) are hinged to each other by a damping hinge (21), and can complete rotation at any angle; the top of the driving box (43) is connected to the front bottom plate (4), and axial holes are symmetrically opened on both sides and a driving shaft sleeve (44) extends out, and a driving motor is installed inside; the driving wheel (41) is concentric with the axial hole and is limited by the driving shaft sleeve (44); there are two adsorption wheels (3), which are respectively connected to the adsorption wheel clamps (46) of the front bottom plate (4) and the rear bottom plate (2); The welding module comprises a mechanical arm (121), a mechanical arm forearm (122), a linear module (123) and a welding gun sleeve (124), wherein the mechanical arm (121) is fixed to the left side of the housing (1), the mechanical arm forearm (122), the linear module (123) and the mechanical arm forearm (122) are connected via a dual-axis steering gear, and the welding gun sleeve (124) and the linear module (123) are connected via a foot; The positioning module includes a depth vision camera (142) and a laser displacement sensor (13), which are fixed to the left side of the housing by bolts; The posture monitoring module comprises a gyroscope, which is built inside the housing (1).

2. The vacuum suction cup wall climbing welding robot according to claim 1, characterized in that: Two drive motors and two drive wheels (41) are respectively installed on the left and right sides of the front bottom plate (4), and a suction wheel (3) is respectively installed on the front bottom plate (4) and the rear bottom plate (2). The diameter of the suction shaft (37) at the center of the suction wheel (3) is smaller than the diameter of the air extraction plate (35) and the air release plate (34).

3. The vacuum suction cup wall climbing welding robot according to claim 1, characterized in that: The centers of the laser displacement sensor (13), the depth vision camera (142), and the robot arm (121) are on the same horizontal line.

4. The vacuum suction cup wall climbing welding robot according to claim 1, characterized in that: The adsorption wheel (3) is a capsule structure, that is, the adsorption shaft (37) is composed of an air passage and an adsorption wheel suction cup (32), the adsorption wheel suction cup (32) is distributed on the shaft surface in a spiral line, and the air intake valve and the air discharge valve are respectively installed on both sides of the adsorption shaft in a hemispherical shape.

5. The vacuum suction cup wall climbing welding robot according to claim 1, characterized in that: The adsorption wheel (3) comprises an air release valve, an adsorption shaft (37) and an air suction valve, wherein the air suction valve comprises an air hood (33) and an air extraction sheet (35), wherein the air extraction sheet (35) is a circular thin sheet with an internal thread, and the air extraction sheet (35) is provided with a maximum of two circular grooves for air passages, and is connected to the adsorption wheel clamp (46) via the internal thread; the air hood (33) and the air extraction sheet (35) are connected by welding to ensure that airflow can only enter and exit through the air hood opening and the groove opening.

6. The vacuum suction cup wall climbing welding robot according to claim 1, characterized in that: The air release valve comprises an air hood (33) and an air release sheet (34). The air release sheet (34) is a circular thin sheet with an internal thread and is connected to the suction wheel clamp (46) via the internal thread. A blocking sheet capable of closing two holes is left on the air release sheet and is connected to the air hood (33) by welding to ensure that the airflow of at most two holes is blocked at the same time.

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