A robot for grinding weld scars on the inner wall of a narrow square tube

Abstract

The present invention discloses a robot for grinding weld scars on the inner wall of a narrow and long square tube, and its structure includes: a chassis, a casing, a steering module, a grinding module, a push rod module, etc. The chassis is provided with a stepper motor, a differential, a transmission shaft, and wheels, which are used for the robot to move linearly in the pipeline; the push rod module includes a stepper motor, a gear rack, and an electric push rod, which are used to fix the body during grinding and fine-tune the lateral position of the body in the pipeline; the grinding module includes a torque motor, a grinding head, a camera, and a steering mechanism, which are used for welding scar grinding and grinding head rotation. The present invention realizes the lateral movement of the robot body with a relatively simple structure through the cooperation of a telescopic push rod and a gear rack; and a steering mechanism is designed to allow the grinding head to achieve 360° rotation, and self-lock after rotating into place, so as to achieve the grinding of the four wall surfaces of the inner wall of the narrow and long square tube.

Description

Technical Field

[0001] The invention relates to the technical field of welding scar grinding, and in particular to a welding scar grinding robot for the inner wall of a narrow and long square tube. Background Art

[0002] Robots are mechanical devices that can work autonomously. With the development of social economy and the progress of science and technology, many dangerous or repetitive jobs are gradually replaced by robots instead of manual labor. In the grinding of the inner wall of the pipeline, many types of robots have been put into use. However, there is no good solution for grinding the weld scars on the inner wall of a narrow square tube whose length is much longer than the side length of the cross section (the length is more than 10 times the side length of the cross section). For example, a company has a batch of narrow square tubes to be polished. The square tube is 4m long and the cross section is a square of 20cm*20cm. There are weld scars with a diameter of about 2cm and a thickness of 1-2mm on each wall of the pipeline. There are 48 weld scars on each pipeline, a total of 32 pipelines, and a total of 1536 weld scars to be polished. If manual grinding is used, it is estimated to take several months to complete. For this reason, it is urgent to invent a grinding robot to efficiently complete the grinding task of narrow square tubes and reduce time costs.

[0003] Most of the existing pipe grinding robots are suitable for grinding the inner wall of round pipes. For example, patent CN113910077A discloses an integrated pipe grinding robot, patent CN110185885B discloses a pipe grinding mobile robot, patent CN307181019S discloses a metal pipe grinding robot, and patent CN204658120U discloses a pipe weld grinding robot. The solutions in the above patents are only suitable for grinding weld scars inside round pipes, and cannot be applied to grinding weld scars on the inner wall of narrow square pipes, and lack special considerations for improving grinding efficiency. When narrow square pipes made by welding technology, such as ventilation ducts, and weld scars inside pipes for storing narrow rectangular objects need to be polished, manual grinding is still the main method. Manual grinding usually uses a rod to extend the grinding head into the pipe. On the one hand, when the grinding position is far away from the inlet, the grinding arm is deformed and the line of sight is limited, making the operation difficult. On the other hand, the grinding force and the grinding head advancement speed are slow due to the limitation of line of sight and the deformation of the rod, resulting in low grinding efficiency. Summary of the invention

[0004] The purpose of the present invention is to provide an efficient narrow and long square tube inner wall weld scar grinding robot in view of the defects of the prior art, which can withstand relatively large grinding speed and force. The robot can simply realize the lateral movement of the fuselage and the turning of the grinding head, and has the advantages of flexible movement and high rigidity, so that it can easily reach any grinding position and realize efficient grinding, which significantly improves the efficiency compared with manual grinding; in particular, when multiple robots are used to work at the same time, multiple narrow and long square tubes can be polished at the same time, while maintaining high efficiency, the cost can be better than the cost of using multiple workers to grind.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A robot for grinding weld scars on the inner wall of a narrow and long square tube, characterized in that it comprises a chassis, a casing, a steering module, and a grinding module, wherein a driving device is arranged on the chassis, and the casing cover is arranged on the chassis, the steering module comprises a turntable, a turntable frame, a limit block, and a top block, the turntable frame is fixedly connected to the outer side of the casing through a connecting plate, the turntable is arranged in the middle part of the turntable frame, and the center of the turntable is rotatably connected to the casing through a connecting rod, the limit block is connected to the inner sides of the upper, lower, left and right sides of the turntable frame through a first spring, and a limit groove matching the limit block is provided on the edge of the turntable, one end of the top block is connected to the driving device through a first transmission shaft, and the other end is close to the edge of the turntable and can squeeze the limit block along the radial direction of the turntable, and the top block is connected to the turntable through a second spring, and the grinding module is fixedly connected to the turntable along the radial direction and corresponds to the position of the limit groove.

[0007] Furthermore, a U-shaped groove is respectively arranged at four positions of the upper, lower, left and right of the turntable frame, and the limit block and the first spring are arranged in the U-shaped groove.

[0008] Furthermore, the limiting block is a wedge-shaped structure.

[0009] Furthermore, the grinding module includes a grinding body, a grinding head, an elastic telescopic rod, and a torque motor. The grinding body is fixedly connected to the turntable, the grinding head is connected to the grinding body through the elastic telescopic rod, and the torque motor is fixedly connected to the grinding body and can drive the grinding head to rotate.

[0010] Furthermore, a camera is connected to the grinding body, and the camera is arranged toward the grinding head.

[0011] Furthermore, it also includes a push rod module, which includes a first electric push rod, a second electric push rod and a third electric push rod, the first electric push rod is vertically arranged in the casing and extends upward out of the casing, the second electric push rod and the third electric push rod are horizontally arranged in the casing and extend left and right out of the casing respectively.

[0012] Furthermore, the push rod module also includes a gear and a rack, the second electric push rod and the third electric push rod are horizontally connected to the two ends of the rack respectively, the center of the gear is connected to the driving device through a second transmission shaft, and the gear and rack are meshed and connected with each other.

[0013] Furthermore, the lower end of the first electric push rod is welded and fixed to the casing.

[0014] Furthermore, the driving device is connected to the wheels to realize the forward and backward movement of the robot.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The present invention overcomes the deficiency of existing grinding robots that can only grind round pipes, and can be used for grinding weld scars of narrow rectangular pipes with long pipes, small pipe openings, and many weld scars. Compared with manual grinding with the help of a long rod inserted into a narrow rectangular pipe, the present invention can significantly improve the grinding efficiency and greatly shorten the grinding time due to the advantages of close operation and accurate positioning.

[0017] 2. The present invention uses an electric push rod and a gear rack to achieve lateral movement of the robot body. Compared with a steering gear, a steering rod assembly or a Mecanum wheel, the electric push rod has a simple structure and low cost. In addition, the electric push rod can stabilize the robot body during grinding, effectively preventing the robot body from shaking due to the force generated by grinding, and ensuring the accuracy during grinding. The realization of two functions through a simple mechanism reflects the multifunctionality of the mechanism, while also reducing the size of the robot body, making it easy for operators to operate and control during work.

[0018] 3. The present invention uses a steering mechanism to achieve 360° steering of the grinding head, which can grind the weld scars on the four sides of the narrow rectangular pipe, further improving the grinding efficiency. At the same time, the self-locking function of the steering mechanism can ensure that the grinding head will not shake during grinding, and combined with the function of the electric push rod to stabilize the body, the grinding accuracy is effectively guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The three-dimensional structure of the present invention is shown in FIG. Figure 1 ;

[0020] Figure 2 The three-dimensional structure of the present invention is shown in FIG. Figure 2 ;

[0021] Figure 3 It is a schematic diagram of the internal structure of the casing of the present invention;

[0022] Figure 4 This is a schematic diagram of the steering module structure of the present invention;

[0023] Figure 5 It is a schematic diagram of the matching state of the limit block and the limit groove of the present invention;

[0024] Figure 6 This is a schematic diagram of the polishing module structure of the present invention;

[0025] Figure 7 It is a schematic diagram of the connection structure between the second electric push rod and the third electric push rod in the push rod module of the present invention;

[0026] Figure 8 This is a schematic diagram of the working state of the present invention when the upper, lower, left, and right sides are polished;

[0027] Fig. 9 This is a schematic diagram of the working state of the present invention when realizing lateral movement;

[0028] Wherein: 1- chassis, 2- housing, 3- steering module, 4- grinding module, 5- driving device, 6- ejector module, 7- wheel, 8- square tube, 9- welding scar, 31- turntable, 32- turntable frame, 33- limit block, 34- ejector block, 35- connecting plate, 36- connecting rod, 37- first spring, 38- first transmission shaft, 39- second spring, 41- grinding body, 42- grinding head, 43- elastic telescopic rod, 44- torque motor, 45- camera, 61- first electric ejector, 62- second electric ejector, 63- third electric ejector, 64- gear, 65- rack, 66- second transmission shaft, 311- limit groove, 321- U-shaped groove. DETAILED DESCRIPTION

[0029] In order to deepen the understanding of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings. The embodiments are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0030] Figure 1 , 2 A specific embodiment of a robot for grinding weld scars on the inner wall of a narrow and long square tube is shown, comprising a chassis 1, a casing 2, a steering module 3, a grinding module 4, and a push rod module 6. A driving device 5 is provided on the chassis 1, and the casing 2 is covered on the chassis 1. The chassis 1 and the casing 2 together constitute a traveling mechanism of the robot. A stepper motor, a differential, and a transmission system are provided on the chassis 1, and are connected to the chassis 1 by screws. The operation of the stepper motor drives the transmission system and transmits it to the wheel 7 to realize the movement of the robot in a straight line direction.

[0031] like Figure 4As shown, the steering module 3 includes a turntable 31, a turntable frame 32, a limit block 33, and a top block 34. The turntable frame 32 is fixedly connected to the outer side of the casing 2 through a connecting plate 35. The turntable 31 is arranged in the middle of the turntable frame 32. The center of the turntable 31 is rotatably connected to the casing 2 through a connecting rod 36. A U-shaped groove 321 is respectively arranged at four positions of the upper, lower, left and right of the turntable frame 32. The limit block 33 is connected to the four U-shaped grooves 321 around the turntable frame 32 through a first spring 37. The limit block 33 adopts a wedge-shaped structure. A limit groove 311 that matches the limit block 33 is opened on the edge of the turntable 31. One end of the top block 34 is connected to the driving device 5 through a first transmission shaft 38, and the other end is close to the edge of the turntable 31 and can squeeze the limit block 33 along the radial direction of the turntable 31. The top block 34 is connected to the turntable 31 through a second spring 39. The grinding module 4 is fixedly connected to the turntable 31 along the radial direction and corresponds to the position of the limit groove 311.

[0032] like Figure 6 As shown, the grinding module 4 includes a grinding body 41, a grinding head 42, an elastic telescopic rod 43, and a torque motor 44. The grinding body 41 is fixedly connected to the turntable 31, the grinding head 42 is connected to the grinding body 41 through the elastic telescopic rod 43, and the torque motor 44 is fixedly connected to the grinding body 41 and can drive the grinding head 42 to rotate. A camera 45 is connected to the grinding body 41, and the camera 45 is set in the direction of the grinding head 42, which can feed back the grinding state image information to the operator in real time, and adjust the position and grinding speed of the robot in time.

[0033] like Figure 3 , 7 As shown, the push rod module 6 includes a first electric push rod 61, a second electric push rod 62, a third electric push rod 63, a gear 64, and a rack 65. The first electric push rod 61 is vertically arranged in the housing 2, and the lower end is welded and fixed to the housing 2 and extends upward out of the housing 2. The second electric push rod 62 and the third electric push rod 63 are horizontally arranged in the housing 2 and extend left and right out of the housing 2 respectively. The second electric push rod 62 and the third electric push rod 63 are horizontally connected to the two ends of the rack 65 respectively, and the center of the gear 64 is connected to the driving device 5 through the second transmission shaft 66, and the gear 64 and the rack 65 are meshed and connected with each other.

[0034] like Figure 8 As shown, when the grinding robot is working, the first transmission shaft 38 drives the top block 34 on the turntable 31 to rotate. After the top block 34 contacts the limit block 33 in the limit groove 311, the first spring 37 is squeezed by the force, and the limit block 33 is separated from the limit groove 311. The top block 34 pulls the turntable 31 to rotate through the second spring 39. When the turntable 31 rotates to make the limit groove 311 cooperate with the next limit block 33, the turntable 31 stops rotating. The state of the limit block 33 and the limit groove 311 is as shown in FIG. Figure 5When working, the grinding robot first grinds the weld scar 9 on the lower side of the inner wall of the square tube 8, as shown in FIG. Figure 8 a. At this time, the torque motor 44 provides power to drive the grinding head 42 to rotate at high speed through the grinding body 41, and the elastic telescopic rod 43 provides the grinding head 42 with a force acting downward vertically on the grinding surface to ensure that the grinding head 42 is in close contact with the plane of the weld scar 9. After the grinding is completed, the steering module 3 is started. At this time, the turntable 31 in the steering module 3 rotates counterclockwise, driving the grinding module 4 to rotate. The grinding head 42 rotates with the grinding body 41, and the welding scar 9 on the right side, upper side, and left side of the inner wall of the narrow square tube 8 is polished in turn. Figure 8 As shown in b, c, and d.

[0035] like Fig. 9 As shown, when the second electric push rod 62 and the third electric push rod 63 on the left and right sides respectively push against the inner walls of the narrow square tube 8 on both sides, the position of the rack 65 is relatively fixed. At this time, the gear 64 is driven by the driving device 5 to move left and right along the rack 65, thereby driving the main body of the entire robot to translate left and right in the horizontal direction, that is, to translate horizontally, so that the grinding module 4 can be aligned with the area to be polished.

[0036] The above specific implementation methods are only for illustrating the technical concept and structural features of the present invention, and the purpose is to enable relevant persons familiar with this technology to implement it. However, the above content does not limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should fall within the protection scope of the present invention.

Claims

1. A robot for grinding weld scars on the inner wall of a narrow square tube, characterized in that: The invention comprises a chassis (1), a casing (2), a steering module (3), and a grinding module (4); the chassis (1) is provided with a driving device (5); the casing (2) is covered on the chassis (1); the steering module (3) comprises a turntable (31), a turntable frame (32), a limit block (33), and a top block (34); the turntable (31) frame is fixedly connected to the outer side of the casing (2) via a connecting plate (35); the turntable (31) is arranged in the middle of the turntable frame (32); the center of the turntable (31) is rotatably connected to the casing (2) via a connecting rod (36); the limit block (33) is connected to the casing (2) via a connecting rod (36); A spring (37) is connected to the inner sides of the upper, lower, left and right sides of the turntable frame (32); a limit groove (311) matching with the limit block (33) is provided on the edge of the turntable (31); one end of the top block (34) is connected to the driving device (5) through a first transmission shaft (38); the other end is close to the edge of the turntable (31) and can press the limit block (33) along the radial direction of the turntable (31); the top block (34) is connected to the turntable (31) through a second spring (39); the grinding module (4) is fixedly connected to the turntable (31) along the radial direction and corresponds to the position of the limit groove (311); It also comprises a push rod module (6), the push rod module (6) comprising a first electric push rod (61), a second electric push rod (62) and a third electric push rod (63), the first electric push rod (61) being vertically arranged in the casing (2) and extending upwards out of the casing (2), the second electric push rod (62) and the third electric push rod (63) being horizontally arranged in the casing (2) and extending leftwards and rightwards out of the casing (2) respectively; When the second electric push rod (62) and the third electric push rod (63) on the left and right sides respectively push against the inner walls of the narrow square tube (8), the position of the rack (65) is relatively fixed. At this time, the gear (64) is driven by the driving device (5) to move left and right along the rack (65), thereby driving the main body of the entire robot to move left and right in the horizontal direction, that is, to move horizontally, so that the grinding module (4) can be aligned with the area to be polished.

2. According to claim 1, a robot for grinding weld scars on the inner wall of a narrow and long square tube, characterized in that: A U-shaped groove (321) is provided at four positions, namely, upper, lower, left and right, of the rotating disk frame (32), and the limit block (33) and the first spring (37) are provided in the U-shaped groove (321).

3. According to claim 2, a robot for grinding weld scars on the inner wall of a narrow and long square tube, characterized in that: The limiting block (33) is a wedge-shaped structure.

4. According to claim 1, a robot for grinding weld scars on the inner wall of a narrow and long square tube, characterized in that: The grinding module (4) comprises a grinding body (41), a grinding head (42), an elastic telescopic rod (43), and a torque motor (44); the grinding body (41) is fixedly connected to the turntable (31); the grinding head (42) is connected to the grinding body (41) via the elastic telescopic rod (43); and the torque motor (44) is fixedly connected to the grinding body (41) and is capable of driving the grinding head (42) to rotate.

5. According to claim 4, a robot for grinding weld scars on the inner wall of a narrow and long square tube, characterized in that: The grinding machine body (41) is connected to a camera (45), and the camera (45) is arranged in the direction of the grinding head (42).

6. According to claim 1, a robot for grinding weld scars on the inner wall of a narrow and long square tube, characterized in that: The push rod module (6) further comprises a gear (64) and a rack (65); the second electric push rod (62) and the third electric push rod (63) are respectively connected horizontally to two ends of the rack (65); the center of the gear (64) is connected to the drive device (5) via a second transmission shaft (66); and the gear (64) and the rack (65) are meshed and connected with each other.

7. A robot for grinding weld scars on the inner wall of a narrow and long square tube according to claim 6, characterized in that: The lower end of the first electric push rod (61) is fixedly welded to the casing (2).

8. A robot for grinding weld scars on the inner wall of a narrow and long square tube according to any one of claims 1 to 7, characterized in that: The driving device (5) is connected to the wheels (7) to achieve forward and backward movement of the robot.

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