A robot constant force milling system suitable for cleaning large steel castings

Abstract

The present invention discloses a robot constant force milling system suitable for cleaning large steel castings, including a constant force pressure regulating device, an inclination sensor, a pressure sensor and a milling device. The inclination sensor and the milling device are arranged on the constant force pressure regulating device. The constant force pressure regulating device is provided with a cylinder, and the cylinder is connected with a gas pressure regulating device. The milling device adjusts the corresponding milling angle according to the surface, meat increase and internal defects of the casting blank. The inclination sensor detects the inclination of the milling device from the vertical direction, and then adjusts the pressure of the cylinder, thereby adjusting the positive pressure of the milling device, so that the positive pressure is always perpendicular to the processing surface. The pressure sensor detects the size of the positive pressure to ensure that the positive pressure is always the same as the set pressure, thereby realizing accurate milling according to the shape of the defect, reducing the amount of welding repair, and saving costs. At the same time, it reduces noise and pollution to the environment, reduces dust concentration, and avoids the damage of dust to the workers' bodies.

Description

Technical Field

[0001] The invention relates to the field of steel casting milling, in particular to a robot constant force milling system suitable for cleaning large steel castings. Background Art

[0002] The shapes of surface, fillet and internal defects of large steel castings are varied. In order to effectively reduce the amount of repair welding for defects in the later stage, when cleaning the defects, it is necessary to perform milling according to the trajectory of the defects to ensure that the cutting force is always perpendicular to the milling surface and the positive pressure remains unchanged, so that the defects are not damaged or expanded during the cleaning process, and the original shape of the defects is maintained, so as to achieve the purpose of reducing the amount of repair welding and reducing costs.

[0003] The existing method of removing defects of large steel castings mainly uses carbon arc gouging to remove defects, and then uses manual grinding and flaw detection to confirm the removal of defects and form welded grooves. Carbon arc gouging is a processing method that uses the high-temperature arc generated between the carbon electrode and the metal to heat the metal locally to a molten state, and uses the high-speed airflow of compressed air to blow away the molten metal, thereby achieving planing and cutting of the metal base material.

[0004] This processing technology cannot perform precise milling according to the shape of the defect, which will destroy the shape of the defect, thereby expanding the volume of the defect, increasing the amount of welding repair of the defect, and increasing the cost. At the same time, it will also generate loud noise, dust and arc light, causing pollution to the environment, and there is no better way to reduce noise and dust. If the operator is not properly protected during operation, occupational deafness and pneumoconiosis will occur. Manual defect elimination based on non-destructive testing records cannot achieve accurate defect elimination, resulting in ineffective or excessive defect elimination, and artificially increasing the workload. The carbon-enhanced layer formed on the surface of the casting, if not completely removed during the later grinding, will cause defects such as cracks in the later repair welding, resulting in repair welding failure, or the formation of defects exposed on the later processing surface, which may cause the product to be scrapped. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a robot constant force milling system suitable for cleaning large steel castings, which solves the problem that the prior art will destroy the defects when cleaning them, causing the defects to expand, thereby increasing the amount of welding repairs on the defects. The problem of dust, loud noise and arc light generated when cleaning defects in the prior art is solved, reducing pollution to the environment and damage to the workers' bodies, while also reducing labor input and worker costs.

[0006] The object of the present invention is achieved through the following technical solutions: A robot constant force milling system suitable for cleaning large steel castings, comprising a constant force pressure regulating device, an inclination sensor, a pressure sensor and a milling device, wherein the milling device is fixed to one side of the constant force pressure regulating device, the inclination sensor is arranged on the pressure regulating device, the inclination sensor is used to measure the inclination angle of the milling device from the vertical direction, and the pressure sensor is used to detect the positive pressure generated by the milling device on the steel casting;

[0007] The constant force pressure regulating device comprises a bottom plate, a top plate and a cylinder, wherein the top plate is slidably arranged on the bottom plate, the milling device is fixed on the side of the top plate away from the bottom plate, the cylinder is arranged between the top plate and the bottom plate and fixed on the bottom plate, the cylinder comprises a piston rod and a cylinder body, one end of the piston rod is arranged in the cylinder body, and the other end extends out of the cylinder body and is fixed to the top plate, and the cylinder is connected to a gas pressure regulating device;

[0008] The air pressure regulating device includes an air pipe a, an air pipe b and an air pressure pump. The piston rod divides the cylinder body into an air inlet chamber and an air outlet chamber. The two ends of the air pipe a are respectively connected to the air inlet chamber and the air pressure pump, and the two ends of the air pipe b are respectively connected to the air outlet chamber and the air pressure pump. Speed ​​regulating valves are installed on the air pipe a and the air pipe b.

[0009] Furthermore, two fixing plates are symmetrically fixed on the top plate along the direction of extension and retraction of the piston rod, and circular holes are opened on the fixing plates, and the milling device is fixedly inserted into the circular holes.

[0010] Furthermore, the milling device includes a cooling sleeve, a spindle sleeve and an electric spindle, the spindle sleeve is fixedly inserted in the cooling sleeve, the electric spindle is rotatably inserted in the spindle sleeve, a milling cutter is installed on the electric spindle, the cooling sleeve is inserted in the circular hole, a fixing plate is fixedly sleeved on the spindle sleeve, and the fixing plate is fixed to the fixing plate by bolts.

[0011] Furthermore, the bottom plate is provided with an installation groove, the cylinder is fixed in the installation groove, two guide rails are symmetrically fixed on the bottom plate along the direction of extension and retraction of the piston rod, a plurality of sliders are symmetrically fixed on the top plate, the sliders are provided with slide grooves, and the slide grooves cooperate with the guide rails.

[0012] Furthermore, a plurality of annular grooves are provided on the outer wall of the main shaft sleeve, and the plurality of annular grooves are arranged at equal intervals. A water inlet and a water outlet are provided on the cooling sleeve, and the water inlet is located above the water outlet. The water inlet is connected to the annular grooves. A sealing ring is provided between the cooling sleeve and the main shaft sleeve, and the sealing ring is located below the water outlet.

[0013] Furthermore, a connecting plate is fixed to one end of the piston rod outside the cylinder body, and the connecting plate is fixedly connected to the top plate by bolts.

[0014] The beneficial effects of the present invention are:

[0015] A robot constant force milling system suitable for cleaning large steel castings includes a constant force pressure regulating device, an inclination sensor and a milling device. The inclination sensor and the milling device are arranged on the constant force pressure regulating device. The constant force pressure regulating device is provided with a cylinder, and the cylinder is connected to an air pressure regulating device. The milling device adjusts the corresponding milling angle according to the different shapes of the defect. The inclination sensor detects the inclination of the milling device from the vertical direction, and then adjusts the pressure of the cylinder, thereby adjusting the positive pressure of the milling device, so that the positive pressure is always perpendicular to the processing surface, and realizes precise milling according to the shape of the defect, reduces the amount of welding repair, and saves costs. At the same time, the traditional carbon arc gouging method for removing defects is abandoned, which reduces noise and environmental pollution, reduces dust concentration, and avoids the damage of dust to the workers' bodies. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the overall structure of a robot constant force milling system suitable for cleaning large steel castings according to the present invention;

[0017] Figure 2 An exploded schematic diagram of a robot constant force milling system suitable for cleaning large steel castings;

[0018] Figure 3 It is a schematic diagram of the structure of an air pressure regulating device in a robot constant force milling system suitable for cleaning large steel castings;

[0019] Figure 4 A front view of a robot constant force milling system suitable for cleaning large steel castings;

[0020] Figure 5 A top view of a robot constant force milling system suitable for cleaning large steel castings;

[0021] Figure 6 The left view of a robot constant force milling system suitable for cleaning large steel castings;

[0022] In the figure, 1-constant force pressure regulating device, 2-inclination sensor, 3-milling device, 4-fixed plate, 5-cooling jacket, 6-spindle sleeve, 8-fixed plate, 9-guide rail, 10-slider, 11-bottom plate, 12-top plate, 13-cylinder, 15-speed regulating valve, 16-piston rod, 17-cylinder body, 18-air pipe a, 19-air pipe b, 20-air pressure pump, 21-water inlet, 22-water outlet, 23-connecting plate. DETAILED DESCRIPTION

[0023] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following.

[0024] like Figure 1 As shown, a robot constant force milling system suitable for cleaning large steel castings includes a constant force pressure regulating device 1, an inclination sensor 2, a pressure sensor and a milling device 3. The milling device 3 is fixed to one side of the constant force pressure regulating device 1. The inclination sensor 2 is provided on the pressure regulating device 1. The inclination sensor 2 is used to measure the inclination angle of the milling device 3 deviating from the vertical direction. The pressure sensor is used to detect the positive pressure generated by the milling device 3 on the steel casting;

[0025] In the specific implementation, the constant force milling system needs to be installed on the six-axis industrial robot, and the fast scanning system needs to be installed on the six-axis industrial robot. The six-axis industrial robot and the constant force milling system are electrically connected to the computer, so that the constant force milling system can intelligently identify the defects of the steel castings, thereby adjusting the constant force milling system to accurately mill the defects. The specific design of the constant force pressure regulating device is as follows:

[0026] Figures 2 to 6 As shown, the constant force pressure regulating device 1 includes a bottom plate 11, a top plate 12 and a cylinder 13, the top plate 12 is slidably arranged on the bottom plate 11, a milling device 3 is fixed on the side of the top plate 12 away from the bottom plate 11, the cylinder 13 is arranged between the top plate 12 and the bottom plate 11, and is fixed on the bottom plate 12, the cylinder 13 includes a piston rod 16 and a cylinder body 17, one end of the piston rod 16 is arranged in the cylinder body 17, and the other end extends out of the cylinder body 17 and is fixed to the top plate 12, and the cylinder 13 is connected to a gas pressure regulating device;

[0027] like Figure 3 As shown, the air pressure regulating device includes an air pipe a18, an air pipe b19 and an air pressure pump 20. The piston rod 16 divides the cylinder body 17 into an air inlet chamber and an air outlet chamber. The two ends of the air pipe a18 are respectively connected to the air inlet chamber and the air pressure pump 20, and the two ends of the air pipe b19 are respectively connected to the air outlet chamber and the air pressure pump 20. Speed ​​regulating valves 15 are installed on the air pipe a18 and the air pipe b19.

[0028] Due to the various shapes of defects, if a six-axis industrial robot is used alone to drive the milling cutter to move along the defect trajectory, the milling depth of the defect surface cannot be guaranteed to be consistent, which destroys the original shape of the defect, resulting in incomplete milling of the defect, affecting the subsequent repair welding effect, or expanding the volume of the defect, and increasing the subsequent repair welding amount. The present application adopts a constant force pressure regulating device 1 to solve this type of problem. The specific solution is: the six-axis industrial robot drives the constant force pressure regulating device 1 to feed along the defect trajectory, the inclination sensor 2 detects the inclination of the milling device 3 from the vertical direction, and adjusts the extension and contraction of the cylinder 13, thereby driving the milling device 3 to extend and contract, so that the milling cutter on the milling device 3 always fits the defect surface, and at the same time ensures that the positive pressure is always perpendicular to the defect surface during the milling cutter cleaning process. At the same time, the pressure sensor detects the positive pressure between the milling cutter on the milling device 3 and the surface of the cast steel part, and by adjusting the pressure of the cylinder 13, it is ensured that the positive pressure is always consistent with the set value, so as to achieve the same depth of milling for defect trajectories of different shapes, so that the defects after milling maintain the original shape, so that the defects are fully cleaned without causing the defects to expand, and the subsequent welding amount is reduced.

[0029] According to the above, two fixing plates 4 are symmetrically fixed on the top plate 12 along the direction of the piston rod 16 extension and contraction, and a circular hole is provided on the fixing plate 4, and the milling device 3 is fixedly inserted in the circular hole. A mounting groove is provided on the bottom plate 11, and the cylinder 13 is fixed in the mounting groove. Two guide rails 9 are symmetrically fixed on the bottom plate 11 along the direction of the piston rod 16 extension and contraction. Several sliders 10 are symmetrically fixed on the top plate 12, and a slide groove is provided on the slider 10, and the slide groove matches the guide rail 9. A connecting plate 23 is fixed on one end of the piston rod 16 outside the cylinder body 17, and the connecting plate 23 is fixedly connected to the top plate 12 by bolts. The milling device 3 is stably fixed on the top plate 12 by the fixing plate 4 to avoid unstable fixation, which causes the electric spindle to generate large vibrations during operation, thereby affecting the milling effect. The cylinder 17 is fixed to the top plate 12 by the connecting plate 23. On the one hand, it ensures that the milling device 3 on the top plate 12 can move along with the movement of the cylinder 17. On the other hand, the slider 10 can slide smoothly on the guide rail 9, ensuring that the cylinder 17 can drive the milling device to move smoothly, thereby ensuring the smoothness of milling and improving the milling accuracy.

[0030] The working process of the above-mentioned constant force pressure regulating device 1 is: adjust the flow rate of the speed regulating valve 15 on the trachea a18 and the trachea b19 to make the air pressure entering the air inlet chamber and the air outlet chamber different. When the air pressure of the trachea a18 is greater than the air pressure of the trachea b19, the piston rod 16 extends, and when the air pressure of the trachea a18 is less than the air pressure of the trachea b19, the piston rod 16 contracts, thereby realizing the extension and retraction of the piston rod 16. The extension and retraction of the piston rod 16 drives the top plate 12 to slide on the bottom plate 11, thereby moving the milling device 3 on the top plate 12.

[0031] According to the above, the steps for precise cleaning of defects using a constant force milling system are:

[0032] Step 1: Use the rapid scanning system to quickly scan each defect on the steel casting, feed the scanning results back to the computer, and obtain the three-dimensional digital model of each defect;

[0033] Step 2: Automatically program the machining trajectory of the six-axis industrial robot using an offline programming system based on the three-dimensional digital model;

[0034] Step 3: Import the program of the machining trajectory into the six-axis industrial robot, so that the constant force milling system on the six-axis industrial robot moves along the defect surface;

[0035] Step 4: The inclination sensor 2 measures the inclination of the milling device 3 from the vertical direction. The inclination sensor 2 feeds back the measurement result to the computer. The computer adjusts the speed regulating valve 15 on the air pressure regulating device according to the fed-back inclination information, so that the cylinder 13 drives the milling device 3 to generate a positive pressure that is always perpendicular to the milling surface to clean the defects.

[0036] According to mathematical modeling, there is a mathematical relationship between the inclination angle of the milling device 3 from the vertical direction and the positive pressure. This relationship is imported into the computer to ensure that each time the milling angle is changed, the positive pressure generated by the milling device 3 is always perpendicular to the milling surface, thereby achieving accurate milling of defects and reducing the subsequent welding amount of defects. It is worth noting that the inclination angle of the milling device 3 from the vertical direction and the positive pressure are different for different materials of the cast steel parts, and it is necessary to achieve the optimal value multiple times. Therefore, when changing the material of the cast steel parts, it is necessary to conduct multiple experiments to measure the optimal values ​​under different materials, and then store them in the computer. When the milling device 3 cleans the defects of the cast steel parts, it can adapt to the various shapes of the defects, will not cause the defects to expand, and reduce the subsequent welding amount of the defects.

[0037] According to the above, the milling device 3 includes a cooling sleeve 5, a spindle sleeve 6 and an electric spindle. The spindle sleeve 6 is fixedly inserted in the cooling sleeve 5, and the electric spindle is rotatably inserted in the spindle sleeve 6. A milling cutter is installed on the electric spindle. The cooling sleeve 5 is inserted in a circular hole. A fixed disk 8 is fixedly sleeved on the spindle sleeve 6, and the fixed disk 8 is fixed to the fixed plate 4 by bolts.

[0038] A plurality of annular grooves are provided on the outer wall of the main shaft sleeve 6, and the plurality of annular grooves are arranged at equal intervals. A water inlet 21 and a water outlet 22 are provided on the cooling sleeve 5. The water inlet 21 is located above the water outlet 22, and the water inlet 21 is connected to the annular groove. A sealing ring is provided between the cooling sleeve 5 and the main shaft sleeve 6, and the sealing ring is located below the water outlet 22.

[0039] Since the electric spindle integrates the motor into the spindle unit and has a very high speed, a large amount of heat will be generated during operation, causing the temperature of the electric spindle to rise, making the thermal and dynamic characteristics of the electric spindle worse, thereby affecting the normal operation of the electric spindle. Therefore, certain measures must be taken to control the temperature of the electric spindle so that it is constant within a certain value. The cooling method of the present application is: injecting coolant from the water inlet 21, and the coolant will fill each annular groove to achieve cooling of the electric spindle. It is worth noting that the cooling method is not unique, and the spindle sleeve 6 can also be replaced with a water-cooled cooler to further improve the cooling efficiency.

[0040] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A robot constant force milling system suitable for cleaning large steel castings, characterized in that: The invention comprises a constant force pressure regulating device (1), an inclination sensor (2), a pressure sensor and a milling device (3), wherein the milling device (3) is fixed to one side of the constant force pressure regulating device (1), the inclination sensor (2) is arranged on the constant force pressure regulating device (1), the inclination sensor (2) is used to measure the inclination angle of the milling device (3) deviating from the vertical direction, and the pressure sensor is used to detect the positive pressure generated by the milling device (3) on the steel casting; The constant-force pressure regulating device (1) comprises a bottom plate (11), a top plate (12) and a cylinder (13); the top plate (12) is slidably arranged on the bottom plate (11); the milling device (3) is fixed to a side of the top plate (12) away from the bottom plate (11); the cylinder (13) is arranged between the top plate (12) and the bottom plate (11) and is fixed to the bottom plate (12); the cylinder (13) comprises a piston rod (16) and a cylinder body (17); one end of the piston rod (16) is arranged in the cylinder body (17) and the other end extends out of the cylinder body (17) and is fixed to the top plate (12); and the cylinder (13) is connected to a gas pressure regulating device; The air pressure regulating device comprises an air pipe a (18), an air pipe b (19) and an air pressure pump (20); the piston rod (16) divides the cylinder body (17) into an air inlet chamber and an air outlet chamber; two ends of the air pipe a (18) are respectively connected to the air inlet chamber and the air pressure pump (20); two ends of the air pipe b (19) are respectively connected to the air outlet chamber and the air pressure pump (20); and speed regulating valves (15) are installed on both the air pipe a (18) and the air pipe b (19); The invention is characterized in that two fixing plates (4) are symmetrically fixed on the top plate (12) along the direction of extension and retraction of the piston rod (16), a circular hole is opened on the fixing plate (4), and the milling device (3) is fixedly inserted into the circular hole; The bottom plate (11) is provided with a mounting groove, the cylinder (13) is fixed in the mounting groove, two guide rails (9) are symmetrically fixed on the bottom plate (11) along the direction of extension and retraction of the piston rod (16), a plurality of slide blocks (10) are symmetrically fixed on the top plate (12), and the slide blocks (10) are provided with slide grooves, which cooperate with the guide rails (9).

2. A robot constant force milling system suitable for cleaning large steel castings according to claim 1, characterized in that: The milling device (3) comprises a cooling sleeve (5), a spindle sleeve (6) and an electric spindle, wherein the spindle sleeve (6) is fixedly inserted into the cooling sleeve (5), the electric spindle is rotatably inserted into the spindle sleeve (6), a milling cutter is mounted on the electric spindle, the cooling sleeve (5) is inserted into the circular hole, a fixing plate (8) is fixedly sleeved on the spindle sleeve (6), and the fixing plate (8) is fixed to the fixing plate (4) by bolts.

3. A robot constant force milling system suitable for cleaning large steel castings according to claim 2, characterized in that: A plurality of annular grooves are provided on the outer wall of the spindle sleeve (6), and the plurality of annular grooves are arranged at equal intervals. A water inlet (21) and a water outlet (22) are provided on the cooling sleeve (5), and the water inlet (21) is located above the water outlet (22). The water inlet (21) is communicated with the annular grooves. A sealing ring is provided between the cooling sleeve (5) and the spindle sleeve (6), and the sealing ring is located below the water outlet (22).

4. A robot constant force milling system suitable for cleaning large steel castings according to claim 3, characterized in that: A connecting plate (23) is fixed to one end of the piston rod (16) located outside the cylinder body (17), and the connecting plate (23) is fixedly connected to the top plate (12) by bolts.

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