A positioning device for railway freight car body maintenance and its usage method

Abstract

A positioning device and its usage method for railway freight car body maintenance relate to the field of railway freight car body repair and welding technology. This invention addresses the problems of poor positioning accuracy and consequently poor repair quality, as well as the time-consuming and labor-intensive nature of manual welding repairs of railway freight cars, leading to low work efficiency. First, a double-sided brake shoe is used for coarse positioning of the car body. Then, the car body is slowly moved closer to the positioning mechanism by manual pushing or a winch in the opposite direction of the car's direction of travel, thus achieving precise positioning. Next, a point laser height sensor is connected to the top of the cutting torch via a locking ring, and positioning is achieved using point laser positioning. Finally, an automatic welding unit calculates the weld trajectory, starting point, and ending point by extracting feature points, thus achieving final positioning of the welding trajectory by the automatic welding unit. This invention is applicable to the maintenance of railway freight car bodies.

Description

Technical Field

[0001] This invention relates to the field of railway freight car body repair and welding technology, specifically to a positioning device for railway freight car body inspection and maintenance and its usage method. Background Technology

[0002] Railway transportation holds a paramount position in my country's modern transportation system, serving as the lifeline of the national economy. Bulk commodities such as coal, timber, metal ores, and grain primarily rely on railways for transport. Heavy-haul freight trains, led by the C70, C64, and C70E models, constitute the mainstay of my country's energy railway transportation network, playing a crucial role in my country's energy strategic security in the new era. This network forms a heavy-haul freight network and a high-speed container transport network, with transportation capacity adapted to the rapid development of the national economy.

[0003] Currently, the inspection and maintenance of railway freight cars is a crucial guarantee for railway transportation safety and freight operation capacity, and a key link in the reuse of car bodies. The steel structure of railway freight car bodies is subjected to the effects of friction and corrosion from goods in a full-temperature environment, and is also subjected to the impact of loading and unloading machinery, leading to damage to the protective layer of the car body. When encountering rainy weather, under the combined effects of corrosion from rainwater and other media, the base material of the car body is corroded, the rust layer is destroyed, and eventually the car body gradually thins until it perforates and fails.

[0004] The current method of railway freight car maintenance and repair is to use manual construction and welding. The car body maintenance work requires different processes such as shot blasting, disassembly, repair and welding. In practice, these processes are distributed in different workshops. Since the bogie has been removed, it is only placed on a dummy car by an overhead crane, and then pulled to a transverse car by a winch and manpower, and then transferred to different rails for construction. It is stopped by a shoe, but since the car weighs more than 20 tons, it is impossible to accurately position the car body by relying on the shoe. Therefore, subsequent automated operations are difficult to continue. In addition, due to the long-term wear and damage of the car body, its positioning benchmark is completely different from that of a newly manufactured car. Its corner posts, crossbars, diagonal ribs and other parts are severely deformed, and the positioning benchmark is seriously missing.

[0005] In summary, the existing technology for welding and repairing railway freight cars manually suffers from poor positioning accuracy, resulting in poor repair quality. Furthermore, the welding and repair process is time-consuming and labor-intensive, leading to significant work efficiency issues. Summary of the Invention

[0006] This invention addresses the problems of poor positioning accuracy and low repair quality in existing manual welding and repair methods for railway freight cars, which result in low work efficiency. It proposes a positioning device and method for railway freight car body inspection and repair.

[0007] The present invention provides a positioning device for the maintenance of railway freight car bodies, which comprises two rails 11, a positioning mechanism, an automatic cutting unit and an automatic welding unit.

[0008] The two rails 11 are arranged in parallel, and each rail 11 is provided with a positioning mechanism in the middle, and an automatic cutting unit and an automatic welding unit are arranged sequentially on the outer side of the rail 11 along the length direction.

[0009] Furthermore, the automatic cutting unit includes a six-axis industrial robot 1, a sensor bracket 2, a universal arm 3, a pen-shaped camera 4, a photo recognition camera 5, a cutting torch 6, a cutting torch connecting seat 7, a laser rangefinder sensor 8, a mounting plate 9, and an anti-collision sensor 10.

[0010] The output end of the six-axis industrial robot 1 is fixedly connected to the side of the mounting plate 9. A cutting torch connecting seat 7 is provided in the middle of the other side of the mounting plate 9. A cutting torch 6 is provided on the cutting torch connecting seat 7. A laser rangefinder sensor 8 is provided at one edge of the other side of the mounting plate 9. A sensor bracket 2 is provided at the other edge of the other side of the mounting plate 9. A photo recognition camera 5 is provided at the bottom of the sensor bracket 2. A universal arm 3 is provided on the sensor bracket 2. A pen-shaped camera 4 is provided at the end of the universal arm 3. An anti-collision sensor 10 is provided on the outer circumference of the output end of the six-axis industrial robot 1.

[0011] Furthermore, the aforementioned photo recognition camera 5 is used to identify the numbers marked on the vehicle body;

[0012] Furthermore, the positioning mechanism includes two fixed plates 12, a stop block 13, a hinge column 14, a positioning shoe 15, and a positioning plate 16;

[0013] One of the rails 11 has a fixed plate 12 on each side of the middle section, and each fixed plate 12 is fixed to the ground by expansion bolts. One of the fixed plates 12 has a hinge post 14 in the middle of the upper surface, and one end of the upper surface of the positioning plate 16 is hinged to the fixed plate 12 through the hinge post 14. The positioning plate 16 has a positioning shoe 15 in the middle of the upper surface, and the other fixed plate 12 has a stop block 13 along the short edge of the upper surface.

[0014] Furthermore, the front of the positioning iron shoe 15 is machined with a slope, and a countersunk hole is machined in the middle of the slope, and a gas nitrogen spring is installed inside the countersunk hole.

[0015] Furthermore, a grip handle 17 is provided at the other end of the upper surface of the positioning plate 16;

[0016] The method of using the railway freight car body inspection and positioning device of the present invention is as follows:

[0017] Step 1: Rotate the positioning shoe 15 around the hinge post 14 to open it, and rotate the positioning shoe 15 to the outside of the rail 11.

[0018] Step 2: The car body is moved to the predetermined position on the rail 11 by a winch or manual pushing;

[0019] Step 3: Manually place the double-sided brake shoes on the rails for rough positioning of the car body;

[0020] Step 4: The double-sided brake shoes contact the outer surface of the wheels of the car body, changing the rolling friction between the wheels and the rails into sliding friction, increasing the frictional resistance, and stopping the car body (this step is coarse positioning).

[0021] Step 5: Rotate the positioning shoe 15 on the positioning mechanism around the hinge post 14 on the fixed plate 12 and rotate it onto the rail 11 so that the back of the positioning shoe 15 contacts the side of the stop block 13 on the fixed plate 12.

[0022] Step 6: Use manpower or a winch to push the vehicle in the opposite direction of the vehicle's direction of travel, so that the vehicle body slowly approaches the positioning mechanism and the outer surface of the vehicle's wheels contacts the end of the gas-nitrogen spring on the positioning shoe 15, thereby accurately positioning the vehicle body.

[0023] Step 7: Mark different numbers on the area to be cut using laser engraving technology (or manual spraying), with each number representing a different cutting trajectory;

[0024] Step 8: An image recognition camera 5 is added to the front of the cutting torch on the automatic cutting unit. The image recognition camera 5 takes pictures of the pre-marked numbers, and then the captured numbers are uploaded to the robot's control system via PLC.

[0025] Step 9: Use the IF / ENDIF instructions in the KRL programming language of the industrial robot arm to determine and call the corresponding cutting program, thereby realizing the positioning of the cutting trajectory; (although the cutting trajectory is determined, the starting point and ending point of the cutting are still uncertain, so further positioning is required).

[0026] Step 10: A point laser height sensor is fixedly connected to the top of the cutting torch via a locking ring. The third positioning is achieved using point laser positioning. The laser point illuminates the material and then slowly moves to the left (or right) diagonal brace until the laser point's position changes abruptly and it immediately returns to the search starting point. Since the industrial robot's outriggers are driven by servo motors, the distance traveled can be accurately determined. By calculating the difference between the traveled distance and the original distance, the offset of the starting point from the initially programmed point is determined. This offset is compensated for to accurately determine the precise position of the cutting starting point.

[0027] Step 11: After the cutting operation is completed, the automatic welding unit uses a laser to emit a linear laser beam under the control of the industrial robot arm and irradiates the surface of the plate. By extracting feature points, the trajectory of the weld, the starting point and the ending point are calculated. The data is then uploaded to the robot's central processing unit, thereby enabling the automatic welding unit to finally locate the welding trajectory.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] This invention overcomes the shortcomings of the prior art by first using double-sided brake shoes to roughly position the vehicle body that needs welding repair.

[0030] Then, a positioning mechanism is installed in the middle of the rail, with a fixed plate on each side of the rail. Each fixed plate is fixed to the ground by expansion bolts. A hinge post is located in the middle of the upper surface of one of the fixed plates, and one end of the positioning shoe is hinged to the fixed plate through the hinge post. A stop is located along the short edge of the upper surface of the other fixed plate. The positioning shoe on the positioning mechanism is rotated around the hinge post on the fixed plate and rotated onto the rail, so that the back of the positioning shoe contacts the side of the stop on the fixed plate. The car body is slowly pushed towards the positioning mechanism by manpower or by a winch in the opposite direction of the car's direction of travel, so that the outer surface of the car's wheels contacts the end of the gas-nitrogen spring on the positioning shoe, thereby accurately positioning the car body.

[0031] Then, a point laser height sensor is fixedly connected to the top of the cutting torch through a locking ring, and a third positioning is achieved by using point laser positioning.

[0032] Finally, the automatic welding unit uses a laser to emit a linear laser beam under the control of the industrial robot arm and irradiates the surface of the plate. By extracting feature points, the trajectory of the weld, the starting point, and the ending point are calculated. The data is then uploaded to the robot's central processing unit, thereby enabling the automatic welding unit to finally locate the welding trajectory.

[0033] In summary, this positioning method employs four consecutive positioning steps, which significantly improves positioning accuracy, thereby enhancing the quality of welding repair and ultimately increasing work efficiency. Attached Figure Description

[0034] Figure 1 This is a three-dimensional structural diagram of the automatic cutting unit in the positioning device for railway freight car body maintenance according to the present invention.

[0035] Figure 2 This is a three-dimensional structural diagram of the positioning mechanism in a positioning device for railway freight car body maintenance according to the present invention. Detailed Implementation

[0036] Specific implementation method one: Combining Figure 1 and Figure 2 This embodiment describes a positioning device for railway freight car body maintenance, which comprises two rails 11, a positioning mechanism, an automatic cutting unit, and an automatic welding unit.

[0037] The two rails 11 are arranged in parallel, and each rail 11 has a positioning mechanism in the middle, and an automatic cutting unit and an automatic welding unit are arranged sequentially on the outer side of the rail 11 along the length direction.

[0038] Specific Implementation Method Two: Combining Figure 1 and Figure 2 This embodiment is a further limitation of the positioning device described in Specific Embodiment 1. The positioning device for railway freight car body maintenance described in this embodiment includes an automatic cutting unit comprising a six-axis industrial robot 1, a sensor bracket 2, a universal arm 3, a pen-tube camera 4, a photo recognition camera 5, a cutting torch 6, a cutting torch connecting seat 7, a laser rangefinder sensor 8, a mounting plate 9, and an anti-collision sensor 10.

[0039] The output end of the six-axis industrial robot 1 is fixedly connected to the side of the mounting plate 9. A cutting torch connecting seat 7 is provided in the middle of the other side of the mounting plate 9. A cutting torch 6 is provided on the cutting torch connecting seat 7. A laser rangefinder sensor 8 is provided at one edge of the other side of the mounting plate 9. A sensor bracket 2 is provided at the other edge of the other side of the mounting plate 9. A photo recognition camera 5 is provided at the bottom of the sensor bracket 2. A universal arm 3 is provided on the sensor bracket 2. A pen-shaped camera 4 is provided at the end of the universal arm 3. An anti-collision sensor 10 is provided on the outer circumference of the output end of the six-axis industrial robot 1.

[0040] Specific implementation method three: Combining Figure 1 and Figure 2This embodiment further defines the positioning device described in Specific Embodiment Two. The positioning device for railway freight car body maintenance described in this embodiment uses a photo recognition camera 5 to recognize the numbers marked on the car body.

[0041] Specific implementation method four: Combination Figure 1 and Figure 2 This embodiment is a further limitation of the positioning device described in Specific Embodiment 1. The positioning device for railway freight car body maintenance described in this embodiment includes two fixing plates 12, a stop block 13, a hinge column 14, a positioning shoe 15 and a positioning plate 16.

[0042] One of the rails 11 has a fixed plate 12 on each side of the middle section, and each fixed plate 12 is fixed to the ground by expansion bolts. One of the fixed plates 12 has a hinge post 14 in the middle of the upper surface, and one end of the upper surface of the positioning plate 16 is hinged to the fixed plate 12 through the hinge post 14. The positioning plate 16 has a positioning shoe 15 in the middle of the upper surface, and the other fixed plate 12 has a stop block 13 along the short edge of the upper surface.

[0043] Specific Implementation Method Five: Combining Figure 1 and Figure 2 This embodiment is a further limitation of the positioning device described in Specific Embodiment 4. The positioning device for railway freight car body maintenance described in this embodiment has a ramp on the front of the positioning shoe 15, and a countersunk hole is machined in the middle of the ramp, and a gas nitrogen spring is provided inside the countersunk hole.

[0044] In this specific embodiment, the front of the positioning shoe 15 is machined with a slope, and a countersunk hole is machined in the middle of the slope, and a gas spring is installed inside the countersunk hole; during fine positioning, the gas spring is used to buffer the wheel and reduce damage to the wheel.

[0045] Specific Implementation Method Six: Combination Figure 1 and Figure 2 This embodiment is a further limitation of the positioning device described in Specific Embodiment 4. The positioning device for railway freight car body maintenance described in this embodiment has a grip handle 17 at the other end of the upper surface of the positioning plate 16.

[0046] In this specific embodiment, a handle 17 is provided at the other end of the upper surface of the positioning plate 16 to facilitate the rotation of the positioning plate 16.

[0047] Specific implementation method seven: Combining Figure 1This embodiment describes a method for using a railway freight car body inspection and positioning device, the specific method of which is as follows:

[0048] Step 1: Rotate the positioning shoe 15 around the hinge post 14 to open it, and rotate the positioning shoe 15 to the outside of the rail 11.

[0049] Step 2: The car body is moved to the predetermined position on the rail 11 by a winch or manual pushing;

[0050] Step 3: Manually place the double-sided brake shoes on the rails for rough positioning of the car body;

[0051] Step 4: The double-sided brake shoes contact the outer surface of the wheels of the car body, changing the rolling friction between the wheels and the rails into sliding friction, increasing the frictional resistance, and stopping the car body (this step is coarse positioning).

[0052] Step 5: Rotate the positioning shoe 15 on the positioning mechanism around the hinge post 14 on the fixed plate 12 and rotate it onto the rail 11 so that the back of the positioning shoe 15 contacts the side of the stop block 13 on the fixed plate 12.

[0053] Step 6: Use manpower or a winch to push the vehicle in the opposite direction of the vehicle's direction of travel, so that the vehicle body slowly approaches the positioning mechanism and the outer surface of the vehicle's wheels contacts the end of the gas-nitrogen spring on the positioning shoe 15, thereby accurately positioning the vehicle body.

[0054] Step 7: Mark different numbers on the area to be cut using laser engraving technology (or manual spraying), with each number representing a different cutting trajectory;

[0055] Step 8: An image recognition camera 5 is added to the front of the cutting torch on the automatic cutting unit. The image recognition camera 5 takes pictures of the pre-marked numbers, and then the captured numbers are uploaded to the robot's control system via PLC.

[0056] Step 9: Use the IF / ENDIF instructions in the KRL programming language of the industrial robot arm to determine and call the corresponding cutting program, thereby realizing the positioning of the cutting trajectory; (although the cutting trajectory is determined, the starting point and ending point of the cutting are still uncertain, so further positioning is required).

[0057] Step 10: A point laser height sensor is fixedly connected to the top of the cutting torch via a locking ring. The third positioning is achieved using point laser positioning. The laser point illuminates the material and then slowly moves to the left (or right) diagonal brace until the laser point's position changes abruptly and it immediately returns to the search starting point. Since the industrial robot's outriggers are driven by servo motors, the distance traveled can be accurately determined. By calculating the difference between the traveled distance and the original distance, the offset of the starting point from the initially programmed point is determined. This offset is compensated for to accurately determine the precise position of the cutting starting point.

[0058] Step 11: After the cutting operation is completed, the automatic welding unit uses a laser to emit a linear laser beam under the control of the industrial robot arm and irradiates the surface of the plate. By extracting feature points, the trajectory of the weld, the starting point and the ending point are calculated. The data is then uploaded to the robot's central processing unit, thereby enabling the automatic welding unit to finally locate the welding trajectory.

Claims

1. A method of using a railway freight car body inspection and positioning device, wherein the railway freight car body inspection and positioning device includes two rails (11), a positioning mechanism, an automatic cutting unit and an automatic welding unit; The two rails (11) are arranged in parallel, and each rail (11) has a positioning mechanism in the middle. The side of the rail (11) is provided with an automatic cutting unit and an automatic welding unit along the length direction. The automatic cutting unit includes a six-axis industrial robot (1), a sensor bracket (2), a universal arm (3), a pen-shaped camera (4), a photo recognition camera (5), a cutting torch (6), a cutting torch connecting seat (7), a laser rangefinder (8), a mounting plate (9), and an anti-collision sensor (10). The output end of the six-axis industrial robot (1) is fixedly connected to the side of the mounting plate (9). A torch connecting seat (7) is provided in the middle of the other side of the mounting plate (9). A torch (6) is provided on the torch connecting seat (7). A laser rangefinder (8) is provided at one edge of the other side of the mounting plate (9). A sensor bracket (2) is provided at the other edge of the other side of the mounting plate (9). A photo recognition camera (5) is provided at the bottom of the sensor bracket (2). A universal arm (3) is provided on the sensor bracket (2). A pen-tube camera (4) is provided at the end of the universal arm (3). An anti-collision sensor (10) is provided on the outer circumference of the output end of the six-axis industrial robot (1). The photo recognition camera (5) is used to recognize the numbers marked on the vehicle body. The positioning mechanism includes two fixed plates (12), a stop (13), a hinge column (14), a positioning shoe (15), and a positioning plate (16). One of the rails (11) has a fixed plate (12) on each side of the middle section, and each fixed plate (12) is fixed to the ground by expansion bolts. One of the fixed plates (12) has a hinge post (14) in the middle of the upper surface. One end of the upper surface of the positioning plate (16) is hinged to the fixed plate (12) through the hinge post (14). The positioning plate (16) has a positioning shoe (15) in the middle of the upper surface. The other fixed plate (12) has a stop block (13) along the short edge of the upper surface. The positioning shoe (15) has a slope on the front and a countersunk hole in the middle of the slope. A gas nitrogen spring is installed inside the countersunk hole. The other end of the upper surface of the positioning plate (16) has a handle (17). Its features are: The specific method is as follows: Step 1: Rotate the positioning shoe (15) around the hinge post (14) to open it, and rotate the positioning shoe (15) to the outside of the rail (11); Step 2: The car body is moved into the predetermined position on the rail (11) by a winch or manual pushing; Step 3: Manually place the double-sided brake shoes on the rails for rough positioning of the car body; Step 4: The double-sided brake shoes contact the outer surface of the wheels of the car body, changing the rolling friction between the wheels and the rails into sliding friction, increasing the frictional resistance, and stopping the car body. This step is called coarse positioning. Step 5: Rotate the positioning shoe (15) on the positioning mechanism around the hinge post (14) on the fixed plate (12) and rotate it onto the rail (11) so that the back of the positioning shoe (15) contacts the side of the stop block (13) on another fixed plate (12). Step 6: Use manpower or a winch to push the vehicle in the opposite direction of the vehicle's direction of travel, so that the vehicle body is close to the positioning mechanism and the outer surface of the vehicle's wheels comes into contact with the end of the gas nitrogen spring on the positioning iron shoe (15), thereby making the vehicle body accurately positioned. Step 7: Mark different numbers on the area to be cut using laser engraving technology or manual spraying. Each number represents a different cutting trajectory. Step 8: The front end of the cutting torch on the automatic cutting unit is equipped with a photo recognition camera (5). The photo recognition camera (5) is used to take pictures of the pre-marked numbers, and then the photographed numbers are uploaded to the robot's control system via PLC. Step 9: Use the IF / ENDIF instructions in the KRL programming language of the industrial robot arm to determine and call the corresponding cutting program, thereby realizing the positioning of the cutting trajectory; although the cutting trajectory is determined, the starting point and ending point of the cutting are still uncertain, so further positioning is required. Step 10: The point laser height sensor is fixedly connected to the top of the cutting torch via a locking ring. The third positioning is achieved using point laser positioning. The laser point illuminates the plate and then moves to the left or right diagonal brace until the laser point's position changes abruptly. It immediately returns to the search starting point. Since the industrial robot's outriggers are driven by servo motors, the distance traveled is accurately determined. By calculating the difference between the traveled distance and the original distance, the offset of the starting point from the initially programmed point is determined. This offset is compensated for to accurately determine the precise position of the cutting starting point. Step 11: After the cutting operation is completed, the automatic welding unit uses a laser to emit a linear laser beam under the control of the industrial robot arm and irradiates the surface of the plate. By extracting feature points, the trajectory of the weld, the starting point and the ending point are calculated. The data is then uploaded to the robot's central processing unit, thereby enabling the automatic welding unit to finally locate the welding trajectory.

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