A flexible cable parallel drive robot for boiler inspection and maintenance

Abstract

The present invention discloses a flexible cable parallel drive robot for boiler inspection and maintenance, including a robot body part, a drive part and a control part. The robot body part is a frame with a multi-faceted cubic structure, and one or more mechanical arm modules are arranged on the frame. The front end of the mechanical arm is equipped with a working module, which can inspect and repair the inspection surface; the frame is also provided with a visual module to realize the recording of the robot movement process and triggering photography. The robot is driven by several groups to control its running trajectory. One end of the steel wire rope in the drive is connected to the drive module, and the other end is connected to the robot in the boiler after passing through the pulley assembly. The drive part is controlled by a control cabinet. The present invention overcomes the barriers of the prior art. The developed flexible cable parallel drive robot has strong load capacity, flexible movement, and is driven by rope support. It is like walking on flat ground under various complex working conditions. It can reach places that people and existing robots cannot reach and complete special operations.

Description

Technical Field

[0001] The invention belongs to the technical field of boiler detection and maintenance equipment, and in particular relates to a flexible-cable parallel-drive robot used for boiler detection and maintenance. Background Art

[0002] Thermal power generation occupies a dominant position in my country's power supply. In the boiler, coal powder releases heat after combustion, and this heat is transferred to the medium in the tube through the water-cooled wall tube, which is converted into superheated steam to drive the steam turbine to generate electricity. Since the operating coal type is worse than the design coal type, high-temperature corrosion of the boiler water-cooled wall is inevitable. High-temperature flames and flue gas flush the water-cooled wall tubes. This corrosion will occur in boilers of any type, parameters, and capacity. Since the height of the water-cooled wall is generally 6-80m, a full-height scaffolding must be erected during maintenance. At present, manual maintenance is generally used for the maintenance of domestic power station boilers, which has a high risk factor, long cycle, poor effect, and high price. Machines replacing people is the trend of boiler maintenance in power plants.

[0003] Since Nippon Kogan Co., Ltd. developed the first magnetic wheeled wall-climbing robot in 1988, the wall-climbing robot industry has developed rapidly. Hitachi of Japan has developed an eight-legged magnetic wall-climbing robot that relies on the adsorption force provided by the magnetic feet to adhere to the wall. However, due to the complex control of the robot's steps, poor movement flexibility, and the use of electromagnets to provide suction, accidental power failures will cause safety hazards.

[0004] Many domestic scientific research units have also conducted a lot of research on boiler wall-climbing robots. Previous studies have shown that wheeled mobile robots have considerable advantages when traveling on relatively flat terrain, with fast and stable movement speed, simpler structure and control, but when traveling on uneven ground, energy consumption will be greatly increased, the role of the wheels will be seriously lost, and the mobility efficiency will be greatly reduced. In order to improve the adaptability of wheels to soft and uneven ground, tracked mobile robots came into being, but the maneuverability of tracked robots on uneven ground is still very poor, and the body shakes severely when traveling.

[0005] However, due to the extremely complex working conditions of the inner wall of the boiler, the above-mentioned robots and other existing robots cannot be used in practice, resulting in boiler inspection and maintenance still being manual work. Summary of the invention

[0006] In order to solve the problems of existing wall-climbing robots such as complex structure, poor versatility, complex control, low flexibility and high cost, the present invention provides a flexible cable parallel drive robot for boiler inspection and maintenance, which overcomes the barriers of the prior art. The flexible cable parallel drive robot of the present invention has strong load capacity, flexible movement, is driven by rope support, and can climb boilers as if walking on flat ground. It can reach places that humans and existing robots cannot reach and complete special operations.

[0007] The object of the present invention is achieved in the following manner:

[0008] A flexible-rope parallel-drive robot for boiler inspection and maintenance, the robot is arranged in the boiler and close to the inner wall of the boiler, a fire-viewing hole 30 is arranged on the furnace wall 29 of the boiler, the robot comprises a robot body part, the robot body part is provided with at least one mechanical arm module, the front end of the mechanical arm module is equipped with a working module 6, the robot body part is also connected with a steel wire rope 22 for driving the robot to walk, the other end of the steel wire rope 22 passes through the fire-viewing hole 30 and is connected to a rope driving module 16 arranged outside the boiler, the rope driving module 16, the mechanical arm module and the working module 6 are all connected to a control cabinet; a first pulley assembly 17 and a second pulley assembly 18 for supporting the steel wire rope 22 are arranged on both sides of the fire-viewing hole 30, the first pulley assembly 17 and the second pulley assembly 18 are respectively located outside the boiler and inside the boiler and are on the same horizontal line.

[0009] In order to monitor the status of the wire rope 22 in time, at least one tension sensor 20 is provided between the first pulley assembly 17 and the fire viewing hole 30. Figure 2 There are three tension sensors 20 , and the steel wire rope 22 passes through the tension sensors 20 . The tension sensors 20 are connected to the control cabinet.

[0010] The rope drive module 16 is provided with a bidirectional overrunning clutch.

[0011] The robot body is also provided with a visual module, which is connected to a control cabinet. The visual module includes a workbench 11 fixed on the robot, on which a camera 13, a depth camera 14 and an illuminator 15 are provided, and a gimbal 12 for supporting the camera 13 is also installed.

[0012] The robotic arm module includes a base 1 installed on the robot body, a first steering gear 7 is installed on the base 1, the first steering gear 7 is connected to a turntable 2, the turntable 2 is connected to a second steering gear 8, the second steering gear 8 is connected to a large arm 3, the large arm 3 is connected to a third steering gear 9, the third steering gear 9 is connected to a middle arm 4, the middle arm 4 is connected to a fourth steering gear 10, the fourth steering gear 10 is connected to a small arm 5, and the small arm 5 carries a working module 6.

[0013] The frame of the robot body is a multi-faceted cube structure, and each face of the multi-faceted cube structure is a triangle or a polygon.

[0014] The rope driving modules 16 are three, four, five, six, eight or more groups, and are symmetrically arranged.

[0015] The control cabinet is set to one, two or four, and the control cabinet includes an electrical circuit, various switches / buttons, an Ethernet communication module, a PLC and its IO module, a host computer and an HMI. The host computer is connected to the PLC through an Ethernet interface. A control program runs in the PLC. The PLC collects position signals of the robot body and stress signals on the wire rope.

[0016] A vertically placed first telescopic rod 21 is arranged between the first pulley assembly 17 and the fire viewing hole 30, and a horizontal support platform 23 is fixedly installed on the top of the first telescopic rod 21. One end of the support platform 23 is fixedly installed with the first pulley assembly 17, and the other end is fixedly installed with a fixing seat 24. The fixing seat 24 fixes a horizontal second telescopic rod 25, and the other end of the second telescopic rod 25 passes through the fire viewing hole 30 and is fixedly installed with the second pulley assembly 18.

[0017] The second telescopic rod 25 includes a front support rod 2501, the front support rod 2501 is outer-connected with a middle support rod 2502, the middle support rod 2502 is outer-connected with a rear support rod 2503, and the front ends of the middle support rod 2502 and the front support rod 2501 are both provided with screws 2504, which are tightened against the front support rod 2501 or the side wall of the front support rod 2501 to fix them.

[0018] Compared with the prior art, the advantages of the present invention are as follows:

[0019] 1. The robot of the present invention is driven by rope support, and the robot body adopts a frame structure, which effectively reduces the weight of the robot itself. Multiple mechanical arms can be arranged on the frame, and each mechanical arm is equipped with different working modules. After the boiler water-cooled wall is inspected, it can be directly repaired to replace manual work, with good work connection and no need to frequently replace working modules;

[0020] 2. The present invention adopts a flexible cable drive mode. The robot is suspended in the boiler by a steel wire rope. Several sets of drive modules are arranged outside the boiler. The drive modules control the retraction and extension of the steel wire rope and the length and speed of the retraction and extension through the control of the control cabinet. The multiple sets of drive modules are controlled together, so that the robot can accurately run along the predetermined trajectory in the boiler to complete the operation task in the boiler;

[0021] 3. The robot body frame of the present invention is equipped with a visual module, which can capture the wear of the boiler water-cooled wall of about 0.5 mm, which can completely replace the previous naked eye observation, and the results are traceable;

[0022] 4. The present invention provides a two-way overrunning clutch in the winch drive module, which can ensure that the robot will not fall off in any abnormal situation of power failure or failure;

[0023] 5. The present invention is provided with a control cabinet, and the position status of the robot, the tension status of the wire rope, the detected data, images, etc. can be displayed on the upper computer display interface of the control cabinet, which is convenient for personnel to check and take countermeasures in time;

[0024] 6. Compared with wheeled, tracked, and legged mobile robots, the present invention has completely changed the adsorption or contact-type movement mode. The robot can be moved precisely through wire rope traction, and can move flexibly in the boiler, as if walking on flat ground, and can reach places that humans cannot reach. With a multi-degree-of-freedom robotic arm, it can almost achieve full coverage of the boiler interior without dead angles, complete special operations, and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic structural diagram of the robot of the present invention.

[0026] Figure 2 It is a structural schematic diagram of the flexible cable driving mechanism of the present invention.

[0027] Figure 3 yes Figure 2 Partial top view.

[0028] Figure 4 It is a structural schematic diagram of the connection between the second telescopic rod and the second pulley assembly.

[0029] Among them, 1 is the base; 2 is the turntable; 3 is the upper arm; 4 is the middle arm; 5 is the lower arm; 6 is the working module; 7 is the first servo; 8 is the second servo; 9 is the third servo; 10 is the fourth servo; 11 is the workbench; 12 is the pan-tilt head; 13 is the camera; 14 is the depth camera; 15 is the lighting lamp; 16 is the rope drive module; 17 is the first pulley assembly; 18 is the second pulley assembly; 19 is the sensor bracket; 20 is the tension sensor; 21 is the first telescopic rod; 22 is the wire rope; 23 is the support platform; 24 is the fixed seat; 25 is the second telescopic rod, 2501 is the front support rod, 2502 is the middle support rod, 2503 is the rear support rod, 2504 is the screw, and 2505 is the bolt; 26 is the boiler rigid frame; 27 is the winch drive module; 28 is the carrying module; 29 is the furnace wall; 30 is the fire viewing hole. DETAILED DESCRIPTION

[0030] like Figure 1-3 As shown, a flexible cable parallel drive robot for boiler inspection and maintenance is provided in the boiler and close to the inner wall of the boiler. A fire viewing hole 30 is provided on the furnace wall 29 of the boiler. The robot includes a robot body part, and the robot body part is provided with at least one mechanical arm module. Figure 1There are four robot arm modules in the middle, and the front end of the robot arm module is equipped with a working module 6. The robot body is also connected with steel wire ropes 22 for driving it to walk. The other end of the steel wire rope 22 passes through the fire viewing hole 30 and is connected to a rope driving module 16 arranged outside the boiler. The rope driving module 16, the robot arm module and the working module 6 are all connected to the control cabinet; the first pulley assembly 17 and the second pulley assembly 18 for supporting the steel wire rope 22 are arranged on both sides of the fire viewing hole 30, and the first pulley assembly 17 and the second pulley assembly 18 are respectively located outside the boiler and inside the boiler and are on the same horizontal line.

[0031] The mechanical arm of the above-mentioned mechanical arm module has multiple degrees of freedom, and the connection between the mechanical arm module and the working module 6 is a detachable connection, which is convenient for replacing different working modules 6. The working module 6 can be an existing manual operation device or other automated operation device. When multiple mechanical arm modules are set, each mechanical arm front end can be equipped with different working modules 6, so that there is no need to frequently change the type of working module 6. In this way, after the robot completes the previous step of work, there is no need to replace the working module 6, and the next step of work can be directly performed through the working module 6 carried by other mechanical arms. The control cabinet can be set on a rigid platform or ground below the outside of the boiler, which is convenient for personnel operation and control. Since the fire viewing hole 30 is provided by the boiler, it can be used by the present invention. In actual application, other penetration methods can be selected according to the specific number of groups driven, as long as it can ensure that the robot body can move flexibly in the boiler. The edge of the furnace wall 29 of the boiler is provided with a photoelectric switch for limit protection. When the wall-climbing robot is in an edge position, it is limited to ensure the normal operation of the wall-climbing robot.

[0032] In order to facilitate real-time monitoring of the state of the wire rope 22, at least one tension sensor 20 is provided between the first pulley assembly 17 and the fire viewing hole 30. The specific number is not limited and is selected according to the actual application. Figure 2 There are three tension sensors 20, and the steel wire rope 22 passes through the tension sensors 20, which are connected to the control cabinet. This structure is convenient for timely grasping the status of the steel wire rope 22 and timely replacing the new steel wire rope 22. The steel wire rope 22 is preferably a high-strength anti-twist steel wire rope.

[0033] In order to ensure that the robot does not fall off in any abnormal situation of power failure or failure, a two-way overrunning clutch is provided in the rope driving module 16. The rope driving module 16 also includes a winch driving module 27, which mainly includes a drum, a servo motor, a driver, a sensor, a reducer, etc., to control the retraction and release of the wire rope 22.

[0034] In order to facilitate real-time monitoring and recording of boiler inner wall conditions, such as Figure 1As shown, the robot body is also provided with a visual module, which is connected to the control cabinet. The visual module includes a workbench 11 fixed on the robot, on which a camera 13, a depth camera 14 and a lighting lamp 15 are provided, and a pan / tilt 12 for supporting the camera 13 is also installed. The camera 13 can realize the video recording and triggering of the movement process, and can capture the wear of the boiler water-cooled wall of about 0.5mm, which can completely replace the previous naked eye observation, and the results are traceable. The lighting lamp 15 is an LED energy-saving lamp, which provides lighting for the working area so that personnel can control the robot to work.

[0035] Preferably, if Figure 1 As shown, the mechanical arm module includes a base 1 installed on the robot body, a first steering gear 7 is installed on the base 1, the first steering gear 7 is connected to the turntable 2, the turntable 2 is connected to the second steering gear 8, the second steering gear 8 is connected to the upper arm 3, the upper arm 3 is connected to the third steering gear 9, the third steering gear 9 is connected to the middle arm 4, the middle arm 4 is connected to the fourth steering gear 10, the fourth steering gear 10 is connected to the small arm 5, and the small arm 5 carries the working module 6. A carrying module 28 is arranged between the small arm 5 and the working module 6. The second steering gear 8 is used to control the rotation angle and speed of the upper arm 3; the third steering gear 9 is used to control the rotation angle and speed of the middle arm 4; the fourth steering gear 10 is used to control the rotation angle and speed of the small arm 5. The mechanical arm module can be fixed to the frame of the robot body through the base 1, the base 1 will not rotate, and the turntable 2, the upper arm 3, the middle arm 4, and the small arm 5 can all rotate. Of course, the mechanical arm module can also be other mechanical arms that can work in the prior art, and the prior art that can realize other functions can also be installed at the corresponding position of the robot described in the present invention to realize the functions described.

[0036] Preferably, in order to reduce the weight of the robot itself and improve the load capacity of the robot, the frame of the robot body is a multi-faceted cube structure, in which each face is a triangle or a polygon. Figure 1 The middle frame is a twenty-sided cubic structure, each side of which is a triangle. The material of the frame can be aluminum alloy or other materials.

[0037] Furthermore, the rope drive modules 16 are three, four, five, six, eight or more groups, and are symmetrically arranged. Since four fire viewing holes 30 are symmetrically arranged on the furnace wall 29 of the boiler itself, the present invention connects the rope drive module 16 with the robot by means of the existing four fire viewing holes 30. In other practical applications, the number of rope drive modules 16 can be increased or decreased according to the situation to better adapt to the actual working conditions.

[0038] Furthermore, the control cabinet is set to one, two or four to control four groups of rope drive modules 16. The control cabinet includes an electrical circuit, various switches / buttons, an Ethernet communication module, a PLC and its IO module, a host computer and an HMI. The host computer is connected to the PLC through an Ethernet interface. Various system parameters can be set in the HMI, and operations such as start and stop can be performed, and images and detection data can be displayed. A control program runs in the PLC, and the PLC collects position signals of the robot body and stress signals on the wire rope.

[0039] The PLC analyzes and processes the received position coordinate signals and stress signals, analyzes the position of the weight node, and the coordinate signals can obtain the displacement, velocity and acceleration of the weight over time, and further obtain the position of the four steel wire ropes 22 in space over time. In the present invention, the position, state of the robot, state of the steel wire rope, detected data, images, etc. can all be displayed on the upper computer display interface, which is convenient for personnel to view and take countermeasures in time.

[0040] In order to support the steel wire rope 22, to adapt to the height of the fire viewing hole 30 of different boilers, and to facilitate the adjustment of the distance between the robot and the inner wall of the boiler, such as Figure 2 As shown, a vertically placed first telescopic rod 21 is arranged between the first pulley assembly 17 and the fire viewing hole 30, a horizontal support platform 23 is fixedly mounted on the top of the first telescopic rod 21, one end of the support platform 23 is fixedly mounted with the first pulley assembly 17, and the other end is fixedly mounted with a fixing seat 24, the fixing seat 24 fixes a horizontal second telescopic rod 25, and the other end of the second telescopic rod 25 passes through the fire viewing hole 30 and is fixedly mounted with the second pulley assembly 18. A sensor bracket 19 is installed in the middle of the support platform 23, and the tension sensor 20 is fixedly mounted on the sensor bracket 19. The center points of the first pulley assembly 17, the sensor bracket 19 and the fixing seat 24 are preferably in a straight line.

[0041] The first telescopic rod 21 is used to adjust the height in the vertical direction, and the second telescopic rod 25 is used to adjust the length in the horizontal direction. The structures of the first telescopic rod 21 and the second telescopic rod 25 are the same, but they can also be different as long as they can achieve telescopic effect. Figure 2 As shown, the rope drive module 16 and the first telescopic rod 21 can be fixed on the boiler rigid frame 26, or on other supporting platforms, and the fixed position can be selected according to the specific site of the factory and mine. The boiler rigid frame 26 can be provided by the boiler itself, or can be additionally installed and welded on the boiler.

[0042] Preferably, if Figure 3 , Figure 4As shown, the second telescopic rod 25 includes a front support rod 2501, the front support rod 2501 is externally connected to the middle support rod 2502, the middle support rod 2502 is externally connected to the rear support rod 2503, the front end of the front support rod 2501 is fixed to the second pulley assembly 18 by bolts 2505, and the front ends of the middle support rod 2502 and the front support rod 2501 are both provided with screws 2504 on the side surfaces, and the screws 2504 are tightened against the front support rod 2501 or the side wall of the front support rod 2501 to fix them.

[0043] When the present invention is working, the PLC sends a control instruction to the servo driver according to the collected position signal of the robot body and the tension signal on the wire rope 22, so as to control the forward or reverse rotation of the servo motor, and then transmits the command to the winch drive module 27 through the reducer to control the movement speed and direction of the robot body through the wire rope 22. Figure 1 In the embodiment, one, two or four control cabinets can be provided to control four sets of rope drive modules 16. The four sets of rope drive modules 16 cooperate with each other to control the speed and length of the retracted and released steel wire ropes 22, so that the robot can move along the required trajectory. After arriving at the work site, the control cabinet controls the robot arm module to work.

[0044] The above is only a preferred embodiment of the present invention. It should be pointed out that for those skilled in the art, several changes and improvements can be made without departing from the overall concept of the present invention. These should also be regarded as the scope of protection of the present invention. These will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A flexible cable parallel drive robot for boiler inspection and maintenance, the robot is arranged in the boiler and close to the inner wall of the boiler, and a fire viewing hole (30) is provided on the furnace wall (29) of the boiler, characterized in that: The robot comprises a robot body part, the robot body part is provided with at least one mechanical arm module, the front end of the mechanical arm module is equipped with a working module (6), the robot body part is also connected with steel wire ropes (22) for driving the robot to walk, the other end of the steel wire rope (22) passes through a fire viewing hole (30) and is connected with a rope driving module (16) arranged outside the boiler, and the rope driving module (16), the mechanical arm module and the working module (6) are all connected to a control cabinet; a first pulley assembly (17) and a second pulley assembly (18) for supporting the steel wire rope (22) are arranged on both sides of the fire viewing hole (30), and the first pulley assembly (17) and the second pulley assembly (18) are respectively located outside the boiler and inside the boiler and are on the same horizontal line; A vertically placed first telescopic rod (21) is provided between the first pulley assembly (17) and the fire viewing hole (30); a horizontal support platform (23) is fixedly mounted on the top of the first telescopic rod (21); one end of the support platform (23) is fixedly mounted with the first pulley assembly (17); the other end of the support platform (23) is fixedly mounted with a fixing seat (24); the fixing seat (24) fixes a horizontal second telescopic rod (25); the other end of the second telescopic rod (25) passes through the fire viewing hole (30) and is fixedly mounted with a second pulley assembly (18).

2. The flexible cable parallel drive robot for boiler inspection and maintenance as claimed in claim 1, characterized in that: At least one tension sensor (20) is provided between the first pulley assembly (17) and the fire viewing hole (30), the steel wire rope (22) passes through the tension sensor (20), and the tension sensor (20) is connected to a control cabinet.

3. The flexible cable parallel drive robot for boiler inspection and maintenance as claimed in claim 1, characterized in that: A bidirectional overrunning clutch is provided in the rope drive module (16).

4. The flexible cable parallel drive robot for boiler inspection and maintenance as claimed in claim 1, characterized in that: The robot body is also provided with a visual module, which is connected to a control cabinet. The visual module comprises a workbench (11) fixed on the robot, on which a camera (13), a depth camera (14) and an illuminator (15) are provided, and a pan / tilt platform (12) for supporting the camera (13) is also installed.

5. The flexible cable parallel drive robot for boiler inspection and maintenance as claimed in claim 1, characterized in that: The robot arm module comprises a base (1) mounted on a robot body, a first steering gear (7) mounted on the base (1), the first steering gear (7) connected to a turntable (2), the turntable (2) connected to a second steering gear (8), the second steering gear (8) connected to a large arm (3), the large arm (3) connected to a third steering gear (9), the third steering gear (9) connected to a middle arm (4), the middle arm (4) connected to a fourth steering gear (10), the fourth steering gear (10) connected to a small arm (5), and the small arm (5) carries a working module (6).

6. The flexible cable parallel drive robot for boiler inspection and maintenance as claimed in claim 1, characterized in that: The frame of the robot body is a multi-faceted cube structure, and each face of the multi-faceted cube structure is a polygon.

7. The flexible cable parallel drive robot for boiler inspection and maintenance as claimed in claim 1, characterized in that: The rope drive modules (16) are three groups, four groups, five groups, six groups, or more than eight groups.

8. The flexible cable parallel drive robot for boiler inspection and maintenance as claimed in claim 1, characterized in that: The control cabinet is set to one, two or four, and the control cabinet includes an electrical circuit, various switches / buttons, an Ethernet communication module, a PLC and its IO module, a host computer and an HMI. The host computer is connected to the PLC through an Ethernet interface. A control program runs in the PLC. The PLC collects position signals of the robot body and stress signals on the wire rope.

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