Six-axis robot intelligent polishing work station and polishing method thereof

Abstract

This invention provides a six-axis robotic intelligent grinding workstation and its grinding method. By integrating roller conveyor, robotic arm, grinding components, and detection module, it achieves integrated operation of automatic workpiece feeding, non-contact detection, and intelligent grinding. The detection module collects data such as the coordinates of the positioning hole center, workpiece contour, and grinding head diameter. The control system generates an adaptive grinding path based on this data, solving the problem of high dependence on workpiece consistency in traditional fixed trajectories. Simultaneously, the grinding components employ a floating motor spindle, achieving flexible radial and axial floating, constant force contact with the workpiece, compensating for clamping and shape deviations, and avoiding over-grinding or under-grinding. The control system also features trajectory compensation and speed compensation, automatically correcting the trajectory radius and maintaining a constant linear speed when the grinding head wears, stabilizing processing quality and extending consumable life. Therefore, this invention can automatically complete the entire process of loading, detection, grinding, and unloading, significantly improving the grinding accuracy of rail transit wheels and brake disc hub holes.

Description

Technical Field

[0001] This invention relates to the field of polishing technology, specifically to a six-axis robotic intelligent polishing workstation and its polishing method. Background Technology

[0002] In the maintenance and manufacturing of rail transit vehicles, high-speed trains, and conventional trains, the surfaces of the hub holes and inner holes of wheels and brake discs need to be roughened by grinding to prepare for the application of molybdenum disulfide during the subsequent wheel pressing process. Traditional processing methods mostly involve manual hand-held tools or specialized rigid grinding equipment, which have significant technical drawbacks. Manual grinding relies on the operator's experience and feel, making it difficult to uniformly control the grinding depth and roughness, resulting in poor processing consistency and problems such as over-grinding, under-grinding, and uneven surface texture.

[0003] To improve automation, some existing technologies have begun to incorporate industrial robots for grinding operations, but certain limitations still exist. For example, most robotic grinding systems rely on preset fixed trajectories and cannot adaptively adjust according to actual workpiece size deviations. When there are manufacturing errors or clamping deviations in the workpiece, uneven grinding or even processing failure can easily occur. In addition, the grinding head will gradually wear down during use, and its diameter change will directly affect the grinding trajectory and linear speed. Existing systems usually fail to achieve real-time compensation for this change, resulting in fluctuations in processing quality.

[0004] Therefore, it is necessary to provide a six-axis robot intelligent grinding workstation and its grinding method that can realize automatic workpiece transportation, precise detection and positioning, adaptive generation of grinding paths, and real-time compensation of grinding trajectory and speed, so as to improve grinding accuracy, consistency and automation level. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a six-axis robotic intelligent grinding workstation, which solves problems such as poor processing consistency, inability to adapt to workpiece deviations, and lack of effective compensation mechanisms after grinding head wear in existing technologies, thereby achieving high-precision, high-consistency, and automated grinding of workpiece hub holes.

[0006] A six-axis robotic intelligent grinding workstation includes a grinding module and a control system. The grinding module includes a grinding chamber with two sets of parallel roller conveyor assemblies on one side for conveying workpieces and cooperating with the grinding assembly to complete the grinding operation. A robotic arm support is located on the other side of the grinding chamber, and a robotic arm is mounted on the support. A mounting base is located at the rotating end of the robotic arm's end joint, and a grinding assembly is mounted on the mounting base. The grinding assembly includes an electric motor, a floating motor spindle located at the output end of the electric motor, and a grinding head located at the end of the motor spindle for roughness grinding. A detection module is located on the top of the grinding chamber for identifying and measuring the center coordinates of the workpiece positioning holes and the workpiece contour, and transmitting the position and dimension data to the control system. The control system is electrically connected to the roller conveyor assemblies, the robotic arm, the grinding assembly, and the detection module. Based on the data fed back from the detection module, the control system controls the robotic arm to drive the grinding assembly to complete adaptive grinding, trajectory compensation, and speed compensation of the workpiece.

[0007] Preferably, the roller conveyor assembly includes a plurality of rollers arranged in parallel, adjacent rollers are connected by a chain, and one of the rollers at the end is connected by a chain to the output end of a first motor.

[0008] Furthermore, a lifting assembly is provided between the rollers of the roller conveying assemblies on both sides. The lifting assembly includes a lifting cylinder and a lifting plate disposed at the output end of the lifting cylinder.

[0009] Preferably, the detection module is a 3D camera, an industrial camera, or a laser sensor.

[0010] Preferably, the grinding chamber is provided with a feed inlet and a discharge outlet on the front and rear sides of the roller conveyor assembly, respectively, and a lifting door is provided at both the feed inlet and the discharge outlet.

[0011] A grinding method using a six-axis robotic intelligent grinding workstation, which automatically grinds the hub holes of wheels or brake discs of high-speed trains or conventional trains using the six-axis robotic intelligent grinding workstation, includes the following steps: Step 1: The workpiece to be processed is fed into the two sets of parallel roller conveyor assemblies inside the grinding chamber from the outside. When the roller conveyor assemblies carry the workpiece to the preset processing area, the roller conveyor assemblies stop operating, completing the workpiece conveying. Step 2: The detection module on the top of the grinding chamber performs non-contact image acquisition on the workpiece, acquiring the workpiece's position data, the three-dimensional coordinates of the center of the top surface of the hub hole of the workpiece to be ground, and the workpiece's contour data. At the same time, the detection module measures the diameter of the grinding head online. Then, the detection module transmits the acquired workpiece position data, three-dimensional coordinates of the center, workpiece contour data, and grinding head diameter data to the control system. Step 3: The control system automatically matches and calls the corresponding workpiece grinding program based on the data transmitted by the detection module. According to the workpiece size and grinding requirements, it automatically sets the grinding head speed, grinding head preload, grinding head travel speed and grinding head feed distance per revolution, and generates an adaptive grinding path by combining the three-dimensional coordinates of the workpiece center and the workpiece contour data. Step 4: The control system drives the robotic arm to move the grinding assembly to the processing start position. The electric motor drives the floating motor spindle and grinding head to rotate. The robotic arm moves the grinding head along the generated path. The floating motor spindle drives the grinding head to achieve flexible floating grinding, so that the grinding head and the workpiece surface maintain constant force contact, and the roughness grinding of the hub hole is completed. Step 5: The control system performs dual automatic compensation based on the real-time measured diameter of the grinding head, including trajectory radius compensation: when the diameter of the grinding head decreases due to wear, the control system automatically adjusts the robot's grinding trajectory radius to offset the dimensional deviation, ensure the grinding position and contour accuracy, and ensure consistent grinding results; and speed compensation: after the diameter of the grinding head decreases, the control system automatically increases the grinding head speed to maintain a constant grinding linear speed, so that the linear speed of the grinding head remains unchanged throughout the entire service life, improving grinding consistency and extending the service life of the grinding head; Step 6: After the grinding process is completed, the electric motor stops running, and the robotic arm drives the grinding components back to the safe standby position. Step 7: The control system starts the roller conveyor assembly, which transports the polished workpiece out through the discharge port. The lifting gates of the inlet and outlet open and close in coordination, and the workstation enters the cycle of loading, inspecting and polishing the next workpiece, realizing continuous automated operation.

[0012] Furthermore, in step two, the detection module identifies the machine type by recognizing the workpiece contour data, automatically distinguishing workpieces of different specifications, and avoiding grinding errors caused by machine type mismatch.

[0013] Furthermore, between steps two and three, there is a workpiece lifting and centering step. The lifting component between the roller conveying components is activated, and the lifting cylinder drives the lifting plate to hold the workpiece, eliminating the conveying gap and clamping deviation, providing a stable processing benchmark for inspection and grinding. After grinding is completed, the lifting plate is reset.

[0014] Furthermore, step five also includes replacing the grinding head when its lifespan expires. The control system compares the current diameter of the grinding head with the preset lower limit diameter in real time. When the diameter reaches the wear limit, the robotic arm is automatically controlled to replace the grinding head. After replacement, the diameter is re-detected and the grinding process continues.

[0015] Furthermore, the floating motor spindle described in step four achieves radial and axial floating through a pneumatic floating unit and an elastic guiding mechanism, which can adapt to workpiece clamping deviation and hub hole error, and maintain the initial center position of the spindle through an elastic reset component to achieve constant force contact grinding.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention provides a six-axis robotic intelligent grinding workstation. By integrating a roller conveyor assembly, a robotic arm, and a grinding assembly within the grinding chamber, and setting a detection module on the top of the grinding chamber, it achieves integrated operation of automatic workpiece conveying, non-contact detection, and grinding processing. The detection module collects the center coordinates and contour data of the workpiece's positioning holes and transmits this data to the control system in real time. This allows the control system to match an adaptive grinding path based on the actual position and size information of the workpiece, thereby controlling the robotic arm to drive the grinding assembly for precise grinding. This effectively overcomes the problem of high dependence on workpiece dimensional consistency in traditional fixed-track grinding methods, significantly improving processing accuracy and consistency.

[0017] Meanwhile, by incorporating a floating motor spindle within the grinding assembly, the grinding head can flexibly float in both radial and axial directions during the grinding process. This maintains a constant force contact with the workpiece, effectively compensating for workpiece clamping errors and surface morphology deviations, preventing localized over- or under-grinding, and further improving grinding quality. Furthermore, this invention uses a detection module to monitor the grinding head diameter in real time, and a control system implements a dual adjustment mechanism of trajectory compensation and speed compensation: when the grinding head diameter decreases due to wear, the grinding trajectory radius is automatically corrected, while the motor speed is increased to maintain a constant grinding linear speed. This ensures stable processing results throughout the entire lifespan of the grinding head, effectively solving the problem of decreased processing accuracy caused by grinding head wear in existing equipment, while extending the effective service life of the grinding head and reducing maintenance costs. Therefore, the six-axis robotic intelligent grinding workstation of this invention achieves a continuous operation process of automatic workpiece transport, automatic detection, and automatic grinding, requiring no frequent manual intervention, significantly improving production efficiency and automation levels.

[0018] This invention also provides a grinding method for a six-axis robotic intelligent grinding workstation. By coordinating the control of the roller conveyor assembly, detection module, control system, robotic arm, and grinding assembly, the entire process of workpiece conveying, detection, grinding, and unloading is automated. Before grinding, the detection module non-contactly acquires the workpiece's position data, three-dimensional coordinates of the center, and contour data, and measures the grinding head diameter online. Based on this data, the control system automatically matches the corresponding workpiece's grinding program and generates an adaptive grinding path, thereby effectively avoiding grinding deviations caused by workpiece size deviations or clamping errors, and improving processing accuracy and consistency.

[0019] During the grinding process, the control system drives the robotic arm to move the grinding components along an adaptive grinding path. An electric motor drives the floating motor spindle and grinding head to rotate. The floating motor spindle enables radial and axial floating of the grinding head, maintaining constant force contact between the grinding head and the workpiece surface, ensuring effective grinding of the hub hole roughness. Simultaneously, the control system performs trajectory and speed compensation based on the grinding head diameter measured in real-time by the detection module. Even with grinding head wear, it maintains a stable grinding trajectory and grinding linear speed, ensuring consistent processing results and extending the grinding head's lifespan.

[0020] Therefore, the grinding method of the six-axis robot intelligent grinding workstation provided in this application not only improves the processing quality, but also enhances production efficiency and system automation level. Attached Figure Description

[0021] Figure 1 This is a three-dimensional structural diagram of the six-axis robot intelligent grinding workstation described in this invention.

[0022] Figure 2 This is a second-angle three-dimensional structural diagram of the six-axis robotic intelligent grinding workstation described in this invention. Figure 3 This is a partial structural diagram of the six-axis robot intelligent grinding workstation described in this invention. Figure 4 This is a three-dimensional structural diagram of the side portion of the six-axis robotic intelligent grinding workstation described in this invention. Figure 5 This is a three-dimensional structural diagram of the third angle portion of the six-axis robotic intelligent grinding workstation described in this invention. Figure 6 This is a three-dimensional structural diagram of the fourth angle portion of the six-axis robotic intelligent grinding workstation described in this invention. Figure 7 This is a partial structural diagram of the six-axis robot intelligent grinding workstation described in this invention. in, 1-Grinding chamber, 10-Robotic arm support, 20-Robotic arm, 30-Mounting base, 31-Grinding assembly, 40-Roller conveyor assembly, 46-Roller, 47-Chain, 48-Lifting plate, 49-Lifting cylinder, 51-Detection module, 67-Electric motor, 68-Grinding head, 69-Oil cooler, 70-Feed inlet, 71-Discharge outlet, 72-Lifting door, 80-Quick-change grinding head storage, 90-Control system, 91-Human machine interface. Detailed Implementation

[0023] The embodiments described below are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] See Figures 1-7 This embodiment provides a six-axis robotic intelligent grinding workstation, which includes a grinding module and a control system 90. The grinding module includes a grinding chamber 1. The grinding chamber 1 provides a closed or semi-closed grinding working space to reduce dust overflow during the grinding process and provides a mounting base for various functional components. Two sets of parallel roller conveyor assemblies 40 are arranged on one side of the grinding chamber 1. The two sets of roller conveyor assemblies 40 are spaced apart and are used to carry and transport workpieces, allowing the workpieces to enter the grinding area in a preset direction. During the grinding process, they cooperate with the grinding assembly 31 to complete the grinding operation. The two sets of parallel roller conveyor assemblies 40 can provide stable support for workpieces of different sizes, preventing the workpieces from tilting or shaking during transport and processing.

[0025] A robotic arm support base 10 is provided on the other side of the grinding chamber 1. The robotic arm support base 10 is used to fix and install the robotic arm 20 and provide a stable support foundation for the robotic arm 20. The robotic arm 20 is mounted on the robotic arm support base 10 and can achieve multi-degree-of-freedom movement under the control of the control system 90 to adapt to grinding needs at different positions and angles. A mounting base 30 is provided at the rotating end of the end joint of the robotic arm 20. A grinding component 31 is provided on the mounting base 30, so that the grinding component 31 can move synchronously with the end joint of the robotic arm 20, thereby realizing the grinding processing of different parts of the workpiece.

[0026] See Figure 5 as well as Figure 7The mounting base 30 is equipped with a grinding assembly 31, which includes an electric motor 67, a floating motor spindle located at the output end of the electric motor 67, and a grinding head 68 located at the end of the motor spindle for roughness grinding. The electric motor 67 provides power output to drive the motor spindle and the grinding head 68 to rotate; the floating motor spindle can generate displacement in the radial and axial directions, thereby achieving flexible floating during the grinding process, so that the grinding head 68 can automatically adjust its position and maintain a close contact with the workpiece surface when it contacts the workpiece; the grinding head 68 is used to roughen the surface of the workpiece to meet the requirements of subsequent processes.

[0027] See Figure 3 A detection module 51 is installed on the top of the grinding chamber 1. This module 51 is used to identify and measure the coordinates of the workpiece positioning hole center, the workpiece contour, and the grinding head 68. Specifically, the detection module 51 acquires the workpiece's position and contour data through a non-contact detection method and transmits this data to the control system 90. Therefore, the detection module 51 can obtain the actual state information of the workpiece and the information of the grinding head 68 before grinding, providing a basis for subsequent grinding path planning.

[0028] See Figures 3-7 The control system 90 is electrically connected to the roller conveyor assembly 40, the robotic arm 20, the grinding assembly 31, and the detection module 51, respectively, for unified control of each assembly. After receiving data from the detection module 51, the control system 90 identifies the workpiece type based on the data, calls the corresponding grinding program, and generates a grinding path matching the actual position and size of the workpiece. Simultaneously, the operating parameters of the grinding assembly 31 can be manually adjusted. The control system 90 controls the robotic arm 20 to drive the grinding assembly 31 to complete adaptive grinding of the workpiece. During the grinding process, the grinding trajectory is corrected based on the actual state of the grinding head 68 to achieve trajectory compensation; simultaneously, the speed of the electric motor 67 is adjusted based on the wear condition of the grinding head 68 to achieve speed compensation, thereby ensuring the stability of the grinding process and the consistency of processing quality. The control system 90 calculates the radius wear difference based on the measured diameter of the grinding head 68 and the initial standard diameter, and automatically corrects the radial offset of the preset annular grinding trajectory of the robotic arm 20 to complete the trajectory radius compensation. At the same time, based on the constant machining linear speed calculation formula and combined with the real-time diameter of the grinding head 68, the output speed of the electric motor is automatically adjusted to maintain a consistent cutting linear speed during the gradual wear of the grinding head, effectively ensuring the uniformity of the workpiece grinding removal amount and surface roughness at different wear stages.

[0029] In actual operation, the roller conveyor assembly 40 transports the workpiece to a preset position within the grinding chamber 1. The detection module 51 detects the workpiece and the grinding head 68 and acquires relevant data. The control system 90 controls the robotic arm 20 to move and drives the grinding assembly 31 to perform the grinding operation based on the detection results. Therefore, this application realizes an automated operation process from workpiece conveying and detection to grinding, improving processing efficiency and reducing manual intervention.

[0030] See Figure 6 , Figure 7 In this embodiment, the roller conveying assembly 40 includes multiple parallel rollers 46. Adjacent rollers 46 are connected by chains 47, and one of the end rollers 46 is connected to the output of a first motor via a chain 47. Specifically, each roller 46 has two gears at one end. The other end is rotatably disposed in the grinding chamber 1. The two gears of each roller 46 are connected to one of the gears of its adjacent rollers 46 on both sides via chains 47, thereby forming a chain 47 linkage relationship among the multiple rollers 46. One of the gears of the end roller 46 is connected to the output of the first motor via a chain 47. Driven by the first motor, the end roller 46 drives its adjacent rollers 46 to rotate sequentially, thereby achieving synchronous rotation of all rollers 46. It should be noted that the first motor in this application is preferably a dual-axis servo motor. Gears are provided on the output shafts on both sides of the dual-axis servo motor. The gears on both sides are connected to the gears of the rollers 46 located at the middle ends of the roller conveying assemblies 40 on both sides through chains 47, so as to drive the roller conveying assemblies 40 on both sides to operate synchronously.

[0031] See Figure 5 Preferably, a lifting assembly is provided between the rollers 46 of the two roller conveyor assemblies 40. The lifting assembly includes a lifting cylinder 49 and a lifting plate 48 disposed at the output end of the lifting cylinder 49. The two lifting assemblies are staggered. When the roller conveyor assemblies 40 drive the wheel or brake disc to the grinding position, the first motor stops operating. At this time, the lifting cylinder 49 drives the lifting plate 48 upward, so that the bottom of the wheel or brake disc is pressed against it, thereby achieving stable support and positioning of the wheel or brake disc, preventing it from shaking or shifting during grinding, improving grinding accuracy, and also preventing pressure changes from squeezing the roller 46. At the same time, because the two lifting assemblies are staggered, the lifting plate 48 can provide multi-point support for the wheel or brake disc at different positions, thereby improving the overall stability of the support and preventing tilting caused by uneven force on the workpiece. After grinding and cleaning, the lifting cylinder 49 drives the lifting plate 48 to descend, making the wheels or brake discs more firmly in contact with the roller conveyor assembly 40. Then the first motor starts and continues to drive the roller conveyor assembly 40 to output the workpiece, realizing continuous operation.

[0032] In this embodiment, the detection module 51 is preferably a 3D camera, but industrial cameras, laser sensors, or lidar can also be selected according to actual application requirements. This embodiment uses a 3D camera to acquire the spatial position and contour feature information of the workpiece through three-dimensional vision acquisition. By scanning the hub hole area of ​​the wheel or brake disc, the center coordinates of the hub hole can be obtained, providing reference positioning data for subsequent grinding operations and enabling automatic positioning processing without the need for special tooling fixtures. Simultaneously, by recognizing the overall contour of the workpiece, it can be used to distinguish workpieces of different specifications or models, thereby avoiding mismatches in the processing program and improving the safety and reliability of equipment operation.

[0033] Furthermore, in this embodiment, a quick-change grinding head storage 80 is also included. The quick-change grinding head storage 80 is located on the side of the grinding chamber 1 and is used to centrally store grinding heads 68 of different specifications or types to meet the processing needs of wheel or brake disc hub holes under different working conditions.

[0034] Specifically, the quick-change grinding head library 80 is provided with multiple grinding head 68 positions, each of which is used to hold a corresponding grinding head 68. These grinding head 68 positions can be arranged in a linear or circular array at preset intervals to facilitate the picking and placing operations of the robotic arm 20. Each grinding head 68 position is equipped with a grinding head 68 presence detection structure. This structure detects the presence of a grinding head 68 at the corresponding position and can take the form of a proximity switch, photoelectric sensor, or mechanical limit switch. When a grinding head 68 is placed in a position, the detection structure outputs a presence signal; when the position is empty or the grinding head 68 is not correctly placed, it outputs an abnormal signal, thus providing a detection basis for the control module and improving the reliability and safety of the automatic grinding head 68 changing process.

[0035] Furthermore, a protective door is provided on the outside of the quick-change grinding head storage 80, which is opened and closed by a cylinder. During normal grinding operations, the protective door is closed to isolate dust and debris generated in the grinding area, preventing them from entering the quick-change grinding head storage 80 and affecting the storage environment of the grinding heads 68. When an automatic grinding head 68 replacement operation is required, the control module controls the cylinder to open the protective door, allowing the robotic arm 20 to enter the area of ​​the quick-change grinding head storage 80 to complete the grinding head 68 replacement. After the grinding head 68 replacement is completed, the protective door closes again to restore the protective state.

[0036] Meanwhile, in this application, the output end of the electric motor 67 is provided with a clamping mechanism for clamping or releasing the grinding head 68 handle. Specifically, the clamping mechanism can adopt an elastic chuck structure, a pneumatic clamping structure, or an electric clamping structure, and achieves locking and releasing of the grinding head 68 handle by radial contraction or opening. During the automatic grinding head 68 changing process, when the grinding head 68 needs to be replaced, the control module controls the robotic arm 20 to move to the target grinding head 68 position corresponding to the quick-change grinding head library 80, so that the currently used grinding head 68 is aligned with the corresponding grinding head 68 position and inserted into the grinding head 68 position. Then, the control mechanism releases the grinding head 68 handle, leaving the used grinding head 68 in the grinding head 68 position. Then, the robotic arm 20 moves to the new target grinding head 68 position, so that the clamping mechanism is aligned with the grinding head 68 handle to be replaced, and the control mechanism clamps the grinding head 68 handle, thereby completing the grinding head 68 retrieval action.

[0037] Preferably, the grinding chamber 1 is provided with a feed inlet 70 and a discharge outlet 71 on the front and rear sides respectively corresponding to the roller conveyor assembly 40, and a lifting door 72 is provided at both the feed inlet 70 and the discharge outlet 71. Specifically, the lifting door 72 can be slidably mounted on the grinding chamber 1 in the vertical direction. The upper end of the lifting door 72 is connected to a lifting drive assembly through a connector. The lifting drive assembly is used to drive the lifting door 72 to move up and down. The lifting drive assembly can be a lifting cylinder 49, an electric push rod, or a motor and lead screw structure. When a lifting cylinder 49 is used, the output end of the lifting cylinder 49 is connected to the lifting door 72. The extension and retraction of the lifting cylinder 49 drives the lifting door 72 to rise or fall in the vertical direction, thereby realizing the opening and closing of the feed inlet 70 or the discharge outlet 71. When a motor and lead screw structure is used, the motor drives the lead screw to rotate, which drives the slider and the lifting door 72 that cooperate with the lead screw to move in the vertical direction, thereby realizing lifting control. In actual use, when a workpiece needs to enter the grinding chamber 1, the lifting door 72 at the feed inlet 70 rises and opens, and the roller conveyor assembly 40 transports the workpiece into the grinding chamber 1. After the workpiece enters, the lifting door 72 falls and closes to reduce dust leakage during the grinding process. When the workpiece is finished, the lifting door 72 at the discharge outlet 71 rises and opens, and the roller conveyor assembly 40 transports the workpiece out of the grinding chamber 1, after which the lifting door 72 closes. Therefore, setting the lifting door 72 helps improve the sealing and safety of the equipment, while reducing the impact of dust leakage on the external environment.

[0038] This application also includes an oil cooler 69 for cooling the electric motor 67. Specifically, the oil cooler 69 circulates cooling oil to remove the heat generated by the electric motor 67 during the grinding process, keeping the motor within a safe operating temperature range and preventing insulation aging or performance degradation due to overheating. After flowing out of the oil cooler 69, the cooling oil enters the heat dissipation chamber or cooling jacket of the electric motor 67 through pipelines, absorbs the motor's heat, and then returns to the oil cooler 69 for continuous and efficient thermal management.

[0039] Meanwhile, the control system 90 is equipped with a human-machine interface 91, through which operators can adjust the above processing parameters. Even during equipment operation, parameters can be modified, thereby achieving non-stop adjustment and improving the flexibility and debugging efficiency of equipment use.

[0040] Therefore, the six-axis robotic intelligent grinding workstation provided by this invention integrates a roller conveyor assembly 40, a robotic arm 20, and a grinding assembly 31 within the grinding chamber 1, and sets up a detection module 51 on the top of the grinding chamber 1, realizing integrated operation of automatic workpiece conveying, non-contact detection, and grinding processing. In this application, the robotic arm 20 is a six-axis robotic arm 20. The detection module 51 collects the center coordinates and contour data of the workpiece positioning hole and transmits the relevant data to the control system 90 in real time. This allows the control system 90 to match an adaptive grinding path based on the actual position and size information of the workpiece, thereby controlling the robotic arm 20 to drive the grinding assembly 31 for precise grinding. This effectively overcomes the problem of high dependence on workpiece size consistency in traditional fixed-track grinding methods, significantly improving processing accuracy and consistency.

[0041] Meanwhile, by incorporating a floating motor spindle within the grinding assembly 31, the grinding head 68 can flexibly float in both radial and axial directions during the grinding process. This maintains a constant force contact with the workpiece, effectively compensating for workpiece clamping errors and surface morphology deviations, preventing localized over- or under-grinding, and further improving grinding quality. Furthermore, the invention utilizes a detection module 51 to monitor the diameter of the grinding head 68 in real time, and a control system 90 implements a dual adjustment mechanism of trajectory compensation and speed compensation. When the diameter of the grinding head 68 decreases due to wear, the grinding trajectory radius is automatically corrected, while the motor speed is increased to maintain a constant grinding linear speed. This ensures stable processing results throughout the entire service life of the grinding head 68, effectively solving the problem of decreased processing accuracy caused by grinding head 68 wear in existing equipment, while extending the effective service life of the grinding head 68 and reducing maintenance costs. Therefore, the six-axis robotic intelligent grinding workstation of this invention achieves a continuous workflow of automatic workpiece transport, automatic detection, and automatic grinding, eliminating the need for frequent manual intervention and significantly improving production efficiency and automation levels.

[0042] A grinding method using a six-axis robotic intelligent grinding workstation, which automatically grinds the hub holes of wheels or brake discs of high-speed trains or conventional trains using the six-axis robotic intelligent grinding workstation, includes the following steps: Step 1: The workpiece to be processed is fed into the grinding chamber 1 by two sets of parallel roller conveyor assemblies 40 from the outside. When the roller conveyor assemblies 40 carry the workpiece to the preset processing area, the roller conveyor assemblies 40 stop operating, completing the workpiece conveying. In this process, the workpiece is stably supported and guided by the two sets of parallel roller conveyor assemblies 40, which can ensure the stability of the workpiece's posture during the conveying process and avoid deviation or tilting, thus providing a good initial positioning basis for subsequent inspection and grinding.

[0043] Step Two: The detection module 51 on top of the grinding chamber 1 performs non-contact image acquisition on the workpiece, acquiring the workpiece's position data, the three-dimensional coordinates of the center of the top surface of the hub hole of the workpiece to be ground, and the workpiece's contour data. Simultaneously, the detection module 51 measures the diameter of the grinding head 68 online. Then, the detection module 51 transmits the acquired workpiece position data, three-dimensional coordinates of the center, workpiece contour data, and grinding head 68 diameter data to the control system 90. This non-contact detection method enables high-precision data acquisition without interfering with the workpiece's state, while simultaneously monitoring the state of the grinding head 68, providing a reliable data foundation for subsequent adaptive control. Step 3: Based on the data transmitted by the detection module 51, the control system 90 automatically matches and calls the corresponding workpiece grinding program. According to the workpiece size and grinding requirements, it automatically sets the grinding head 68's rotational speed, preload, grinding travel speed, and per-circuit feed distance. It then generates an adaptive grinding path by combining the workpiece's three-dimensional center coordinates and contour data. It should be noted that the control system 90 first performs coordinate system transformation and spatial positioning calculations on the workpiece's position data and center three-dimensional coordinates to determine the workpiece's actual installation posture and offset within the grinding chamber 1, and corrects the preset grinding program accordingly. Simultaneously, the control system 90 performs boundary identification and path planning for the grinding area based on the workpiece's contour data, fitting the original standard grinding trajectory with the actual contour to form an adaptive grinding path that matches the current workpiece.

[0044] Step 4: The control system 90 drives the robotic arm 20 to move the grinding assembly 31 to the processing start position. The electric motor 67 drives the floating motor spindle and the grinding head 68 to rotate. The robotic arm 20 moves the grinding head 68 along the generation path. The floating motor spindle drives the grinding head 68 to achieve flexible floating grinding, so that the grinding head 68 maintains constant force contact with the workpiece surface to complete the roughness grinding of the hub hole. Through the flexible compensation effect achieved by the floating motor spindle, the grinding head 68 can adapt to the small morphological changes of the workpiece surface, thereby effectively avoiding the problem of uneven grinding in some areas and ensuring the stability of grinding quality.

[0045] Step 5: The control system 90 performs dual automatic compensation based on the real-time measured diameter of the grinding head 68, including trajectory radius compensation: when the diameter of the grinding head 68 decreases due to wear, the control system 90 automatically adjusts the robot's grinding trajectory radius to offset dimensional deviations, ensuring grinding position and contour accuracy, and ensuring consistent grinding results; and speed compensation: after the diameter of the grinding head 68 decreases, the control system 90 automatically increases the speed of the grinding head 68 to maintain a constant grinding linear speed, ensuring that the linear speed of the grinding head 68 remains constant throughout its service life, improving grinding consistency, and extending the service life of the grinding head 68; in the specific implementation process, the control system 90 compares the current actual diameter of the grinding head 68 with the initially set diameter based on the three-dimensional coordinates of the workpiece center and the workpiece contour data obtained by the detection module 51, calculates the change in the radius of the grinding head 68, and maps this change to the radial offset of each trajectory point in the adaptive grinding path, thereby correcting the original grinding path by expanding or contracting it as a whole, so that the corrected grinding trajectory always remains consistent with the actual area to be ground on the workpiece. Furthermore, for workpieces of different sizes or contours, the control system 90 performs segmented matching of the trajectory compensation amount according to the corresponding workpiece's grinding program. This means applying corresponding compensation parameters to different depths or contour areas of the hub hole, making the compensation result more closely match the actual processing requirements and avoiding local over-compensation or under-compensation. Simultaneously, regarding speed compensation, the control system 90 calculates the target speed required to maintain a constant linear velocity in real time based on the diameter change of the grinding head 68 and the radius of the current grinding trajectory, and dynamically adjusts the output of the electric motor 67 to ensure that the grinding head 68 maintains a consistent linear velocity under different workpieces and trajectory positions, thereby ensuring a stable material removal rate throughout the grinding process. In addition, the control system 90 links trajectory compensation and speed compensation, simultaneously updating the speed parameters of the corresponding path segment while correcting the path. This ensures that the grinding component 31 maintains a stable contact state and processing rhythm when executing the compensated adaptive grinding path, further improving adaptability to different workpieces and the consistency of overall grinding quality. Step 6: After the polishing process is completed, the electric motor 67 stops running, and the robotic arm 20 drives the polishing assembly 31 back to the safe standby position. Step 7: The control system 90 controls the roller conveyor assembly 40 to start, conveying the polished workpiece outward through the discharge port 71; the inlet 70 and the discharge port 71 lifting door 72 cooperate to open and close, and the workstation enters the cycle of loading, inspecting and polishing the next workpiece, realizing continuous automated operation.

[0046] Furthermore, in step two, the detection module 51 identifies the workpiece type by recognizing the workpiece contour data, automatically distinguishing workpieces of different specifications to avoid grinding errors due to model mismatch. Specifically, the detection module 51 acquires the overall three-dimensional contour data of the workpiece through non-contact image acquisition and extracts key feature parameters of the workpiece, including outer diameter, hub hole diameter, hub hole depth, contour curve shape, and feature edge position. These feature parameters are then compared and analyzed with the standard workpiece model database pre-stored in the control system 90, thereby achieving automatic identification and classification of the workpiece type.

[0047] Furthermore, a workpiece lifting and centering step is provided between step two and step three. The lifting component between the roller conveying components 40 is activated, and the lifting cylinder 49 drives the lifting plate 48 to hold the workpiece, eliminating the conveying gap and clamping deviation, providing a stable processing benchmark for inspection and grinding. After grinding is completed, the lifting plate 48 is reset.

[0048] Furthermore, step five also includes replacing the grinding head 68 when its lifespan expires. The control system 90 compares the current diameter of the grinding head 68 with the preset lower limit diameter in real time. When the diameter reaches the wear limit, the robotic arm 20 automatically replaces the grinding head 68. After replacement, the diameter is re-detected and the grinding process continues.

[0049] Furthermore, the floating motor spindle described in step four achieves bidirectional flexible floating through pneumatic drive combined with elastic guidance. The entire spindle is coaxially assembled between the electric motor output end and the grinding head, and mainly consists of a spindle fixing sleeve, a floating spindle body, a pneumatic floating unit, an elastic guiding mechanism, and an elastic reset component. The spindle fixing sleeve is rigidly connected to the electric motor output end, and the floating spindle body is nested inside it. The rear end of the floating spindle body is connected to the electric motor output shaft via a flexible coupling, ensuring stable power transmission without affecting the floating action. The front end is fixed to the grinding head via a clamping mechanism, achieving synchronous rotational grinding. The pneumatic floating unit is integrated between the spindle fixing sleeve and the floating spindle body. It consists of an annular air chamber, an air inlet, and a pressure regulating valve. By inputting stable air pressure through an external air source, a uniform air film is formed in the annular air chamber, providing adjustable axial constant force and radial buffer force for the floating spindle body, achieving micro-floatability of ±5mm axially and 360°±3° radially. The elastic guiding mechanism adopts a circumferentially arranged elastic guide sleeve, which is fitted in the middle of the floating spindle body to constrain the floating direction and avoid circumferential offset or jamming during the floating process, ensuring precise and controllable floating action. The elastic reset component uses a circumferentially evenly distributed compression spring. One end abuts against the inner wall of the spindle fixing sleeve, and the other end is connected to the floating spindle body. During the grinding operation, it can extend and retract synchronously with the floating movement. After the grinding head is separated from the workpiece, it drives the floating spindle body to quickly reset to the initial center position, ensuring the consistency of the reference for each grinding. This enables constant force contact grinding between the grinding head and the inner wall of the workpiece hub hole, adaptively compensating for workpiece clamping deviation, hub hole roundness error and form and position deviation, and eliminating over-grinding and under-grinding.

[0050] In the actual grinding process, when the grinding head 68 contacts the inner wall of the workpiece hub hole, if there is workpiece installation eccentricity, roundness error or local dimensional fluctuation, the motor spindle can generate a slight displacement under the action of the pneumatic floating unit, so that the grinding head 68 automatically fits the actual contour of the workpiece; at the same time, the elastic reset component provides a continuous return force to the motor spindle, so that it can return to the vicinity of the initial center position in time after the offset, thereby maintaining the dynamic balance of the overall grinding process.

[0051] This invention also provides a grinding method for a six-axis robotic intelligent grinding workstation. By coordinating the control of the roller conveyor assembly 40, the detection module 51, the control system 90, the robotic arm 20, and the grinding assembly 31, the entire process of workpiece conveying, detection, grinding, and unloading is automated. Before grinding, the detection module 51 non-contactly acquires the workpiece's position data, three-dimensional coordinates of the center, and contour data, and measures the diameter of the grinding head 68 online. Based on the data, the control system 90 automatically matches the corresponding workpiece grinding program and generates an adaptive grinding path, thereby effectively avoiding grinding deviations caused by workpiece size deviations or clamping errors, and improving processing accuracy and consistency.

[0052] During the grinding process, the control system 90 drives the robotic arm 20 to move the grinding assembly 31 along an adaptive grinding path. The electric motor 67 drives the floating motor spindle and the grinding head 68 to rotate. The floating motor spindle enables the radial and axial floating of the grinding head 68, maintaining a constant force between the grinding head 68 and the workpiece surface, thus ensuring the grinding effect on the roughness of the hub hole. At the same time, the control system 90 performs trajectory compensation and speed compensation for the grinding process based on the diameter of the grinding head 68 measured in real time by the detection module 51. Even when the grinding head 68 is worn, it can still maintain the stability of the grinding trajectory and grinding linear speed, thereby ensuring the consistency of the processing effect and extending the service life of the grinding head 68.

[0053] Therefore, the grinding method of the six-axis robot intelligent grinding workstation provided in this application not only improves the processing quality, but also enhances production efficiency and system automation level.

[0054] The above-disclosed embodiments are merely some preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A six-axis robotic intelligent grinding workstation, comprising a grinding module and a control system, characterized in that: The grinding module includes a grinding chamber. Two sets of parallel roller conveyor assemblies are arranged on one side of the grinding chamber to transport workpieces and cooperate with the grinding assembly to complete the grinding operation. A robotic arm support is located on the other side of the grinding chamber. A robotic arm is mounted on the robotic arm support, and a mounting base is located at the rotating end of the robotic arm's end joint. A grinding assembly is mounted on the mounting base. The grinding assembly includes an electric motor, a floating motor spindle located at the output end of the electric motor, and a grinding head located at the end of the motor spindle for roughness grinding. A detection module is located on the top of the grinding chamber. The detection module is used to identify and measure the center coordinates of the workpiece positioning holes and the workpiece contour, and transmit the position and dimension data to the control system. The control system is electrically connected to the roller conveyor assembly, the robotic arm, the grinding assembly, and the detection module. Based on the data fed back by the detection module, the control system controls the robotic arm to drive the grinding assembly to complete the adaptive grinding, trajectory compensation, and speed compensation of the workpiece.

2. The six-axis robot intelligent grinding workstation as described in claim 1, characterized in that, The roller conveyor assembly includes a plurality of rollers arranged in parallel, adjacent rollers are connected by a chain, and one of the rollers at the end is connected by a chain to the output end of a first motor.

3. The six-axis robot intelligent grinding workstation as described in claim 2, characterized in that, A lifting assembly is provided between the rollers of the roller conveying assemblies on both sides. The lifting assembly includes a lifting cylinder and a lifting plate disposed at the output end of the lifting cylinder.

4. The six-axis robot intelligent grinding workstation as described in claim 1, characterized in that, The detection module is a 3D camera, an industrial camera, or a laser sensor.

5. The six-axis robot intelligent grinding workstation as described in claim 1, characterized in that, The grinding chamber is provided with a feed inlet and a discharge outlet on the front and rear sides of the roller conveyor assembly, respectively, and a lifting door is provided at both the feed inlet and the discharge outlet.

6. A grinding method using a six-axis robotic intelligent grinding workstation, wherein the six-axis robotic intelligent grinding workstation described in any one of claims 1 to 5 automatically grinds the hub holes of wheels or brake discs of high-speed trains or conventional trains, characterized in that... It includes the following steps: Step 1: The workpiece to be processed is fed into the two sets of parallel roller conveyor assemblies inside the grinding chamber from the outside. When the roller conveyor assemblies carry the workpiece to the preset processing area, the roller conveyor assemblies stop operating, completing the workpiece conveying. Step 2: The detection module on the top of the grinding chamber performs non-contact image acquisition on the workpiece, acquiring the workpiece's position data, the three-dimensional coordinates of the center of the top surface of the hub hole of the workpiece to be ground, and the workpiece's contour data. At the same time, the detection module measures the diameter of the grinding head online. Then, the detection module transmits the acquired workpiece position data, three-dimensional coordinates of the center, workpiece contour data, and grinding head diameter data to the control system. Step 3: The control system automatically matches and calls the corresponding workpiece grinding program based on the data transmitted by the detection module. According to the workpiece size and grinding requirements, it automatically sets the grinding head speed, grinding head preload, grinding head travel speed and grinding head feed distance per revolution, and generates an adaptive grinding path by combining the three-dimensional coordinates of the workpiece center and the workpiece contour data. Step 4: The control system drives the robotic arm to move the grinding assembly to the processing start position. The electric motor drives the floating motor spindle and grinding head to rotate. The robotic arm moves the grinding head along the generated path. The floating motor spindle drives the grinding head to achieve flexible floating grinding, so that the grinding head and the workpiece surface maintain constant force contact, and the roughness grinding of the hub hole is completed. Step 5: The control system performs dual automatic compensation based on the real-time measured diameter of the grinding head, including trajectory radius compensation: when the diameter of the grinding head decreases due to wear, the control system automatically adjusts the robot's grinding trajectory radius to offset the dimensional deviation, ensure the grinding position and contour accuracy, and ensure consistent grinding results; and speed compensation: after the diameter of the grinding head decreases, the control system automatically increases the grinding head speed to maintain a constant grinding linear speed, so that the linear speed of the grinding head remains unchanged throughout the entire service life, improving grinding consistency and extending the service life of the grinding head; Step 6: After the grinding process is completed, the electric motor stops running, and the robotic arm drives the grinding components back to the safe standby position. Step 7: The control system starts the roller conveyor assembly, which transports the polished workpiece out through the discharge port. The lifting gates of the inlet and outlet open and close in coordination, and the workstation enters the cycle of loading, inspecting and polishing the next workpiece, realizing continuous automated operation.

7. The grinding method of the six-axis robot intelligent grinding workstation as described in claim 6, characterized in that, In step two, the detection module identifies the machine type by recognizing the workpiece contour data, automatically distinguishing workpieces of different specifications, and avoiding grinding errors caused by incompatible machine types.

8. The grinding method of the six-axis robot intelligent grinding workstation as described in claim 6, characterized in that, Between steps two and three, there is a workpiece lifting and centering step. The lifting component between the roller conveying components is activated, and the lifting cylinder drives the lifting plate to hold the workpiece, eliminating the conveying gap and clamping deviation, providing a stable processing benchmark for inspection and grinding. After grinding is completed, the lifting plate is reset.

9. The grinding method of the six-axis robot intelligent grinding workstation as described in claim 6, characterized in that, Step five also includes replacing the grinding head when its lifespan expires. The control system compares the current diameter of the grinding head with the preset lower limit diameter in real time. When the diameter reaches the wear limit, the robotic arm is automatically controlled to replace the grinding head. After replacement, the diameter is re-detected and the grinding process continues.

10. The grinding method of the six-axis robot intelligent grinding workstation as described in claim 6, characterized in that, The floating motor spindle described in step four achieves radial and axial floating through a pneumatic floating unit and an elastic guiding mechanism. It can adapt to workpiece clamping deviation and hub hole error, and maintain the initial center position of the spindle through an elastic reset component to achieve constant force contact grinding.

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