Magnet surface defect detection device and method

Abstract

The invention discloses a magnet surface defect detection device and method, and particularly relates to the field of magnet production.The device comprises a machine base, a conveying structure is arranged on the machine base, and a feeding assembly, a coloring assembly and a visual recognition detection system are sequentially arranged on the machine base in the conveying direction of the conveying structure; the coloring assembly comprises a closed pressing cylinder, the closed pressing cylinder is installed above the machine base in a sliding mode, a pigment cavity is formed between the closed pressing cylinder and the magnet, the closed pressing cylinder is provided with a pigment channel and an input and output pipe, and the machine base is further provided with a scraper structure. According to the invention, the dye liquid overflows the upper surface of the magnet for coloring, so that the bulges or the salient points can be distinguished, and the pigment liquid can permeate into the cracks, so that during actual detection, the contrast of the defects on the surface of the magnet is strong, the defects are easier to recognize, especially the recognition degree of the salient points can be greatly improved, and the detection accuracy is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of magnet production, and more specifically, to a device and method for detecting surface defects of magnets. Background Art

[0002] The components of magnets are iron, cobalt, nickel and other atoms. Magnets can generate magnetic fields and have the characteristics of attracting ferromagnetic materials such as iron, nickel, cobalt and other metals, and have a wide range of applications.

[0003] Among them, the most widely used in modern industry is the neodymium iron boron magnet. As the third generation of rare earth permanent magnet new materials, neodymium iron boron magnets have very high performance and are widely used in energy, transportation, machinery, medical, IT, home appliances and other industries. Especially with the development of the knowledge economy represented by information technology, new uses are constantly being brought to the rare earth permanent magnet neodymium iron boron industry and other functional materials, which brings a broader market prospect for the neodymium iron boron industry.

[0004] NdFeB magnets are mainly formed by sintering. Neodymium, iron, boron and other raw materials are finely mixed in a certain proportion and prepared into alloy powder through powder metallurgy technology. The powder is then pressed and sintered. During the sintering process, the bonding force between the alloy powder particles is enhanced to form a dense crystal structure, which improves the magnetic properties and mechanical strength of the magnet. Among them, since NdFeB materials are easily oxidized and affect the quality, some protective surface treatments are required, such as nickel plating, zinc plating and gold plating, to form an electroplating layer on the surface of the magnet for protection. Finally, the magnet is placed in a specific magnetic field for magnetization (i.e. magnetization) to make the magnet magnetic and become the final product.

[0005] Among them, during the magnet pressing and other processing and forming processes, defects such as pits and convex spots are inevitable on the product surface. In the process of pressing and sintering, it is also easy to cause stress concentration inside the magnet, which leads to cracks. During electroplating, it is easy to cause uneven thickness of the electroplated layer on the surface of the magnet after electroplating or contain convex spots due to problems such as uneven current density distribution and suspended matter in the plating solution. In other words, surface defects are easy to occur in the production process of magnets. For some scenarios with high product requirements, the quality of the final product needs to be guaranteed, so the surface quality of the magnet needs to be tested.

[0006] Since visual recognition detection has high precision and reliability, can be used flexibly, has high automation efficiency, and can monitor and feedback data in real time, in the existing technology, visual recognition technology is used to detect the surface of the product for complete automated detection. However, for small and medium-sized magnets, the production cost is low and there are many production processes. If visual recognition detection equipment is set up in each process, the equipment cost will be high. Therefore, visual inspection equipment can be added at the end of the process to detect surface defects of the final product.

[0007] However, since the surface of the magnet forms a bright metal structure after electroplating, it has a strong reflective phenomenon. During actual visual inspection, it is easy to misjudge tiny pits, bumps and cracks on the product surface due to reflection, thus affecting the detection accuracy. Summary of the invention

[0008] The present invention provides a device and method for detecting defects on the surface of magnets, and aims to solve the problem that in the existing detection method, the surface of the magnet after electroplating reflects light, which easily leads to misjudgment of tiny pits, bumps and cracks on the surface of the product, thereby affecting the detection accuracy.

[0009] To achieve the above object, the present invention provides the following technical solutions: a magnet surface defect detection device, comprising a machine base, a conveying structure is arranged on the machine base, and a feeding component, a coloring component and a visual recognition detection system are arranged on the machine base in sequence along the conveying direction of the conveying structure; A positioning boss is provided on the conveying structure, a positioning groove for accommodating a magnet is provided in the positioning boss, a feeding assembly is used to put the magnet into the positioning boss, and a visual recognition detection system is used to perform visual detection on the upper surface of the magnet; The coloring component includes a closed pressing cylinder, which is slidably mounted above the machine base. When the positioning boss reaches the bottom of the closed pressing cylinder, the closed pressing cylinder descends and plugs into the positioning boss, and a pigment cavity is formed between the closed pressing cylinder and the magnet. A pigment channel and an input and output pipe are arranged on the closed pressing cylinder. The pigment channel is connected to the pigment cavity and the input and output pipes. The input and output pipes are respectively connected to an injection pump and a liquid extraction pump through a tap, wherein the injection pump is used to inject pigment liquid into the pigment cavity, and the liquid extraction pump is used to extract the pigment liquid from the pigment cavity. A scraper structure is also arranged on the machine base, and the scraper structure cooperates with the upper surface of the magnet.

[0010] In a preferred embodiment, the conveying structure is a conveying belt, the positioning boss and the conveying belt are integrally formed, and when the magnet is placed in the positioning groove, the top plane of the positioning boss is lower than the upper surface of the magnet. The closed pressure cylinder is connected to the machine base through a mounting frame, and the mounting frame is fixedly mounted on the machine base. The closed pressure cylinder is slidably mounted on the mounting frame, and a lifting drive is also fixedly mounted on the mounting frame. The closed pressure cylinder is fixedly mounted on the output end of the lifting drive.

[0011] In a preferred embodiment, the visual recognition detection system includes a CCD camera and a light source, the light source is used to illuminate the colored magnet, the CCD camera is used to capture images of the upper surface of the magnet, and the CCD camera and the light source are fixedly mounted on a mounting frame.

[0012] In a preferred embodiment, a liquid level sensor is provided in the area of ​​the pigment chamber corresponding to the upper surface of the magnet, an overflow hole is provided on the side wall of the pigment chamber, the overflow hole is connected to the outside of the closed pressure cylinder, the overflow hole is provided above the upper surface of the magnet, a heater is fixedly installed in the pigment chamber, a vacuum chamber is provided at a position corresponding to the overflow hole outside the closed pressure cylinder, a vacuum chamber is fixedly installed on the vacuum chamber, and the vacuum pipe is connected to a vacuum pump.

[0013] In a preferred embodiment, an inner support frame is provided in the machine base, the inner support frame is arranged in close contact with the conveying structure, and a accommodating groove is provided in the inner support frame at a position below the closed pressing cylinder, a turntable is rotatably installed in the accommodating groove, a driving motor is installed on the inner support frame, the driving motor is used to drive the turntable to rotate, a first adsorption magnetic component is fixedly installed in the turntable, the first adsorption magnetic component is eccentrically arranged with the turntable, and the first adsorption magnetic component is used to magnetically adsorb the magnet.

[0014] In a preferred embodiment, a plurality of fixed protrusions are fixedly mounted on the inner wall of the accommodating groove, and an elastic protrusion is fixedly mounted on the side wall of the turntable. When the turntable rotates, the elastic protrusion and the fixed protrusion touch each other to generate vibration.

[0015] In a preferred embodiment, the loading assembly includes a support frame, a storage barrel and a unloading barrel. The support frame is fixedly mounted on the machine base, the storage barrel is fixedly mounted on the support frame, and the unloading barrel is also fixedly mounted in the support frame. A transfer box is arranged between the unloading barrel and the storage barrel, a pusher is fixedly mounted on the transfer box, a push block is slidably mounted in the transfer box, and the push block is fixedly mounted on the output end of the pusher.

[0016] In a preferred embodiment, a second adsorption magnetic component is fixedly installed on the inner support frame at a position corresponding to the unloading barrel, and the second adsorption magnetic component is used to adsorb the magnet. An air blowing pipe is fixedly installed on the transfer box at a position corresponding to the unloading barrel, and the air blowing pipe is connected to an air pump.

[0017] In a preferred embodiment, a swivel is slidably provided inside the lower barrel, an elastic retaining ring is fixedly installed on the inner wall of the swivel, the elastic retaining ring is a flexible structure, a protruding column is fixedly installed on the outer wall of the swivel, a downward-inclined slide groove is provided on the inner wall of the lower barrel, the protruding column is slidably provided in the downward-inclined slide groove, and an elastic member is provided in the protruding column for providing an upward elastic force to the protruding column.

[0018] A method for detecting surface defects of a magnet comprises the following steps: Step 1: Place multiple magnets that have been magnetized into a columnar shape into a storage barrel, and push them into a discharge barrel by a push block to make them fall and land on the corresponding positioning boss to complete the loading; Step 2: The conveying structure drives the magnet to move, and the magnet stops when it moves to the bottom of the closed pressing cylinder. The closed pressing cylinder falls and docks with the positioning boss. The injection pump injects the pigment liquid into the pigment cavity so that the liquid level of the pigment liquid overflows the upper surface of the magnet for coloring. Step 3, control the liquid extraction pump to extract the pigment liquid in the pigment chamber, and then control the closed pressure cylinder to move upward; Step 4: The conveying structure continues to drive the magnet to move, and the visual recognition detection system performs image recognition on the upper surface of the colored magnet to determine whether there is an area on the surface that cannot be colored due to protrusions; Step 5: The magnet passes through the scraper structure to scrape off the paint on the upper surface; Step 6: The visual recognition detection system performs image recognition again on the upper surface of the magnet after the paint is scraped off to determine whether there are areas on the surface where the paint cannot be scraped off due to cracks and pits.

[0019] The beneficial effects of the present invention are as follows: the present invention allows the dye liquid to flow over the upper surface of the magnet for coloring, so that protrusions or convex points can be distinguished, and the pigment liquid can penetrate into the cracks, so that during actual detection, the contrast of the defects on the magnet surface is strong and easier to identify, especially the recognition of convex points can be greatly improved, thereby enhancing the detection performance of the equipment, and after the scraper structure scrapes off the pigment on the surface of the magnet, the pigment in the cracks can be retained, and the cracks and pits can be clearly displayed during identification and detection, especially for cracks that are difficult to observe with the naked eye. After the pigment penetrates, it is easier to be identified by a visual recognition detection system, thereby greatly improving the accuracy of equipment recognition. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0021] Figure 2 It is a schematic diagram of the detection process of the present invention.

[0022] Figure 3 It is a schematic structural diagram of the coloring component of the present invention.

[0023] Figure 4 It is a schematic diagram of the structure of the closed pressing cylinder and the positioning boss when they cooperate with each other in the present invention.

[0024] Figure 5 It is a schematic diagram of the structure after the pigment liquid of the present invention flows over the upper surface of the magnet.

[0025] Figure 6 This is a state diagram of the magnet entering the detection area of ​​the present invention.

[0026] Figure 7 It is a schematic diagram of the upper surface of the magnet of the present invention after being colored by the pigment liquid.

[0027] Figure 8 It is a schematic diagram of the structure of the magnet of the present invention when passing through the scraper structure.

[0028] Fig. 9 It is a schematic structural diagram of the scraper structure of the present invention when the pigment on the surface of the magnet is scraped off and the pigment remains in the cracks and pits on the surface.

[0029] Fig.10 It is a schematic structural diagram of the improved coloring component of the present invention.

[0030] Fig.11 This is a state diagram of the first adsorption magnetic member of the present invention when it rotates eccentrically in the turntable.

[0031] Fig.12 It is a schematic diagram of the overall structure of the magnet feeding assembly of the present invention.

[0032] Fig.13 The figure is a schematic diagram of the overall structure of the improved magnet feeding assembly of the present invention.

[0033] Fig.14 It is a schematic diagram of the structure of the rotating ring in the discharge barrel of the present invention.

[0034] Fig.15 It is a top view of the rotating ring of the present invention in the lower barrel.

[0035] Fig.16 The present invention is a flow chart of the detection method.

[0036] The accompanying drawings are marked as follows: 1, base; 11, inner support frame; 12, accommodating groove; 121, fixing protrusion; 13, turntable; 131, elastic protrusion; 14, first adsorption magnetic member; 15, driving motor; 16, second adsorption magnetic member; 17, impact pad; 2, conveying structure; 21, positioning boss; 3, loading assembly; 31, support frame; 32, storage barrel; 33, transfer box; 331, blowing pipe; 34, pusher; 341, push block; 35, unloading barrel; 3 51. Downward chute; 36. Rotating ring; 361. Boss; 362. Elastic retaining ring; 4. Visual recognition detection system; 41. CCD camera; 42. Light source; 5. Coloring component; 51. Closed pressing cylinder; 511. Pigment chamber; 512. Pigment channel; 513. Input and output pipes; 514. Liquid level sensor; 515. Overflow hole; 516. Heater; 517. Exhaust chamber; 518. Exhaust pipe; 52. Lifting drive; 6. Magnet; 7. Scraper structure. DETAILED DESCRIPTION

[0037] The present application is further described in detail below in conjunction with the accompanying drawings. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technical personnel in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0038] Refer to the instruction manual Figures 1 to 15 A device and method for detecting surface defects of magnets include a machine base 1, on which a conveying structure 2 is arranged, and on which a feeding component 3, a coloring component 5 and a visual recognition detection system 4 are arranged in sequence along the conveying direction of the conveying structure 2.

[0039] The conveying structure 2 is a commonly used conveying structure, such as a conveying belt, a conveying chain plate, etc., and a positioning boss 21 is provided on the conveying structure 2. A positioning groove is provided in the positioning boss 21 for accommodating the magnet 6 and positioning the magnet 6. When the magnet 6 is placed in the positioning groove, the top plane of the positioning boss 21 is lower than the upper surface of the magnet 6, that is, a part of the side wall of the magnet 6 is still exposed. When the positioning boss 21 passes through the loading component 3, the loading component 3 is used to place the magnet 6 into the positioning boss 21, so that the magnet 6 follows the conveying structure 2 for transportation.

[0040] The coloring component 5 includes a closed pressing cylinder 51, which is slidably installed above the machine base 1. The closed pressing cylinder 51 is arranged corresponding to the positioning boss 21. When the positioning boss 21 carries the magnet 6 to the bottom of the closed pressing cylinder 51, the closed pressing cylinder 51 descends. The bottom of the closed pressing cylinder 51 is provided with a bayonet that engages with the positioning boss 21, so that the closed pressing cylinder 51 can be docked with the positioning boss 21, and the positioning boss 21 is inserted into the closed pressing cylinder 51. It should be noted that in this embodiment, the conveying structure 2 is preferably a conveyor belt structure, and the positioning boss 21 can be integrally formed with the conveyor belt, so that the conveying structure 2 and the positioning boss 21 have a certain flexibility. After the closed pressing cylinder 51 is docked with the positioning boss 21, a relative seal can be formed. In order to improve the sealing effect, a sealing pad structure can also be provided at the bottom of the closed pressing cylinder 51.

[0041] When the closed pressing cylinder 51 is plugged into the positioning boss 21, a pigment cavity 511 is formed between the closed pressing cylinder 51 and the magnet 6, that is, the inner wall of the closed pressing cylinder 51 does not fit the magnet 6, but leaves a certain space. The closed pressing cylinder 51 is provided with a pigment channel 512 and an input / output tube 513. The pigment channel 512 is connected to the pigment cavity 511 and the input / output tube 513. The input / output tube 513 is respectively connected to the injection pump and the liquid extraction pump through a tap. The injection pump is connected to the pigment liquid through a pipeline. After the closed pressing cylinder 51 and the positioning boss 21 are completely docked, the injection pump is controlled. The pigment liquid is injected into the pigment cavity 511 through the pigment channel 512, so that the liquid level of the pigment liquid gradually rises in the pigment cavity 511 and gradually overflows the upper surface of the magnet 6. The injection amount of the pigment liquid can be determined according to calculation until the pigment liquid can overflow the surface of the magnet 6 but not overflow too much. For example, when the pigment channel 512 is completely filled with the pigment liquid, the distance from the surface of the pigment liquid to the upper surface of the magnet 6 is between 0.1-0.3 mm, so that the pigment can cover the upper surface of the magnet 6 and complete the coloring of the upper surface of 6. However, refer to the attached manual. Figure 5 When the surface of the magnet 6 has some protrusions or convex points due to processing errors, the pigment cannot flow over the above-mentioned protrusions or convex points (the pigment is allowed to flow over for smaller acceptable protrusions and convex points). When there are cracks on the surface of the magnet 6, the pigment liquid will also penetrate into the cracks, especially when the cracks are extremely small, the pigment liquid will also penetrate into the cracks due to capillary action and color the cracks.

[0042] After coloring is completed, the liquid pump is controlled to extract the pigment liquid in the pigment chamber 511, and then the closed pressure cylinder 51 is controlled to move upward, and then the conveying structure 2 is controlled to drive the magnet 6 to continue conveying, and convey it to the detection area of ​​the visual recognition detection system 4, and the magnet 6 is visually recognized. At this time, if there are protrusions or convex points on the surface of the magnet 6 that are not colored, the recognition image is as follows Figure 5 As shown, after coloring, the surface contrast of the magnet 6 is strong, and defects are easier to identify, especially the recognition of convex points can be greatly improved, enhancing the detection performance of the equipment. At the same time, a scraper structure 7 is also provided on the base 1. The scraper structure 7 is used to cooperate with the upper surface of the magnet 6, and when the magnet 6 passes through the scraper structure 7, the pigment on the surface of the magnet 6 is scraped off. However, since the pigment has penetrated into the cracks, the pigment in the cracks and the pigment in the pits on the surface of the magnet 6 cannot contact the scraper structure 7 and will not be scraped off. During the identification detection, the surface image of the magnet 6 is as shown in FIG. Fig. 9 As shown, cracks and pits can be clearly displayed, especially cracks that are difficult to observe with the naked eye. After the pigment penetrates, they are easier to be identified by the visual recognition detection system 4, which greatly improves the accuracy of equipment recognition.

[0043] It should be noted that the pigment liquid used in this embodiment is preferably a dark pigment, wherein a pigment with good adhesion is required, such as the pigment liquid in a marker pen (which can adhere to the metal surface), and the closed pressure cylinder 51 is connected to the base 1 through a mounting frame, and the sealing ... Figure 3 The mounting frame is fixedly mounted on the machine base 1, the closed pressure cylinder 51 is slidably mounted on the mounting frame, and a lifting drive 52 is also fixedly mounted on the mounting frame. The closed pressure cylinder 51 is fixedly mounted on the output end of the lifting drive 52, wherein the lifting drive 52 can be a pneumatic cylinder or a hydraulic cylinder.

[0044] In this embodiment, the visual recognition detection system 4 includes a CCD camera 41 and a light source 42. The light source 42 is used to illuminate the magnet 6 after coloring, and the CCD camera 41 is used to collect images of the surface of the magnet 6. After the system recognizes it, it is compared with the images of the coloring and paint scraping conditions on the surface of the magnet 6 that meets the standards for recognition, so as to determine whether the magnet 6 is qualified and complete the surface defect detection of the magnet 6. The CCD camera 41 and the light source 42 are also installed on the base 1 through a mounting frame, wherein the CCD camera 41 and the light source 42 are fixedly installed on the mounting frame, and for smaller magnets 6, the scraper structure 7 can be directly set in the middle position below the CCD camera 41, and the recognition area of ​​the CCD camera 41 is divided into two. A group of CCD cameras 41 recognizes the magnet 6 before and after the paint is scraped off. When the magnet 6 is large, two groups of CCD cameras 41 can be set, respectively located on both sides of the scraper structure 7, for sequential recognition. Among them, the relevant schemes of the visual recognition detection system 4 are all commonly used visual recognition technologies summarized in the prior art, and the detailed schemes are not repeated in this embodiment.

[0045] In the above embodiment, in order to improve the stability and accuracy of the pigment liquid level in the pigment chamber 511, refer to the attached manual. Figure 4 A liquid level sensor 514 is provided in the area of ​​the pigment cavity 511 corresponding to the upper surface of the magnet 6, and an overflow hole 515 is provided on the side wall of the pigment cavity 511. The overflow hole 515 is connected to the outside of the closed pressure cylinder 51, and the overflow hole 515 is provided above the upper surface of the magnet 6. Furthermore, based on the pre-calculated and determined amount of pigment liquid injection, the liquid level height of the pigment liquid can be identified in real time through the liquid level sensor 514 to ensure that the pigment can overflow the upper surface of the magnet 6 but not overflow unqualified protrusions or projections. Even if there is too much pigment in the pigment cavity 511, it can overflow from the overflow hole 515 to ensure the accuracy of coloring.

[0046] Further, in order to reduce the tension of the pigment liquid and improve its fluidity on the surface of the magnet 6, a corresponding activator can be added to the pigment, or refer to the attached manual. Fig.10, the coloring component 5 is improved, that is, a heater 516 is fixedly installed in the pigment chamber 511, which can heat the dye liquid, improve its fluidity and reduce its tension, and an exhaust chamber 517 is provided at the position corresponding to the overflow hole 515 on the outside of the closed pressing cylinder 51, and an exhaust pipe 518 is fixedly installed on the exhaust chamber 517, and the exhaust pipe 518 is connected to a vacuum pump, and then before the pigment liquid is injected, the pigment chamber 511 can be evacuated first to avoid the formation of bubbles in the cracks of the magnet 6 that affect the coloring. At the same time, after evacuation, the pigment liquid has stronger fluidity in the pigment chamber 511, which can improve the covering effect on the magnet 6.

[0047] For further information, please refer to the attached manual. Fig.10 In order to allow the pigment liquid to fully flow over the magnet 6, an inner support frame 11 is provided in the machine base 1, and the inner support frame 11 is arranged in contact with the conveying structure 2, and a receiving groove 12 is provided in the inner support frame 11 at a position below the closed pressing cylinder 51, and a turntable 13 is rotatably installed in the receiving groove 12, and a driving motor 15 is installed on the inner support frame 11, and the driving motor 15 is used to drive the turntable 13 to rotate, and a first adsorption magnetic member 14 is fixedly installed in the turntable 13, and the first adsorption magnetic member 14 is eccentrically arranged with the turntable 13, and the first adsorption magnetic member 14 is used to adsorb the magnet 6 Magnetic adsorption is performed. During the actual coloring process, since the first adsorption magnetic member 14 is relatively eccentric to the turntable 13 and the magnet 6, under the adsorption effect of the first adsorption magnetic member 14, one side of the magnet 6 can be relatively tilted (the conveying structure 2 uses a conveyor belt, and the conveyor belt has a certain flexibility), but the degree of inclination is relatively small. During the rotation of the turntable 13, the inclination direction of the magnet 6 is constantly changing, which can enhance the flow effect of the pigment liquid flowing over the surface of the magnet 6 on the surface of the magnet 6, and increase the covering speed of the pigment liquid on the magnet 6.

[0048] Refer to the instruction manual Fig.10 and 11 A plurality of fixed protrusions 121 are fixedly installed on the inner wall of the accommodating groove 12, and an elastic protrusion 131 is fixedly installed on the side wall of the turntable 13. When the turntable 13 rotates, the elastic protrusion 131 and the fixed protrusion 121 touch each other to form vibration, which can drive the magnet 6 to generate a small vibration, further improving the pigment covering effect.

[0049] In the above embodiment, the scraper structure 7 can directly use a straight scraper, and its two ends are fixedly installed on the machine base 1 through a mounting structure, and the bottom of the scraper structure 7 corresponds to the position of the magnet 6 using rubber or other flexible structures to prevent the scraper structure 7 from being lifted by protrusions on the surface of the magnet 6. In order to clean the scraper structure 7, a cleaning structure that can slide along the length direction of the scraper structure 7 can also be provided on the scraper structure 7. After each scraping of the paint, the cleaning structure is driven to slide along the scraper structure 7 to wipe the scraper structure 7. The cleaning structure can use a sponge or other structure. Since the relevant cleaning schemes are all commonly used simple schemes and there are many specific schemes, this embodiment will not be explained in detail.

[0050] In this embodiment, the magnetized magnets 6 can be detected, and the magnetized magnets 6 are mutually adsorbed to form a columnar structure, and are not easily separated from each other. For this reason, this embodiment provides a loading component 3 for conveniently loading the magnetized magnets 6. For details, refer to the attached manual. Figure 2 and Fig.12 The loading assembly 3 includes a support frame 31, a storage barrel 32 and a discharge barrel 35. The support frame 31 is fixedly mounted on the machine base 1, the storage barrel 32 is fixedly mounted on the support frame 31, and the discharge barrel 35 is also fixedly mounted in the support frame 31. A transfer box 33 is provided between the discharge barrel 35 and the storage barrel 32. A pusher 34 is fixedly mounted on the transfer box 33. A push block 341 is slidably mounted in the transfer box 33. The push block 341 is fixedly mounted on the output end of the pusher 34. When loading, The magnets 6 that are attracted to each other to form a columnar structure can be inserted into the storage barrel 32. Before each insertion, pay attention to the uniform direction of the magnetic poles of the magnets 6. When the positioning boss 21 stays below the lower barrel 35, the pusher 34 drives the push block 341 to move, and pushes the magnet 6 at the bottom of the storage barrel 32 laterally to make it leave the storage barrel 32 and move to the lower barrel 35 in the transfer box 33 until it falls from the lower barrel 35 and falls on the positioning boss 21 to complete the loading.

[0051] Furthermore, since the magnets 6 will gradually form magnetic force during the magnetization process, the originally dispersed magnets 6 will attract and contact each other, and it is easy to form collisions at this time, causing some unqualified magnets 6 with large internal attraction to have internal cracks. However, due to the presence of the coating, the appearance of the cracks is affected and it is not easy to detect. For this reason, please refer to the attached manual for details. Fig.13, this embodiment also improves the loading component 3, wherein the lowering barrel 35 can be set to form a certain height, increase the falling distance of the magnet 6, and improve its impact force when falling. At the same time, a second adsorption magnetic component 16 is fixedly installed at the position corresponding to the lowering barrel 35 on the inner support frame 11. The second adsorption magnetic component 16 is used to adsorb the magnet 6. Since the conveying structure 2 in this embodiment adopts a conveyor belt, which has a certain flexibility, an impact pad 17 is fixedly installed above the second adsorption magnetic component 16 at the position corresponding to the lowering barrel 35. The impact pad 17 uses a structure that has no effect on the magnetic field, such as a high-strength plastic plate, etc., to accelerate the falling speed of the magnet 6 in the lowering barrel 35, so that the lowering barrel 35 can form a larger impact when loading, increase the original cracks of the magnet 6 (for qualified magnets 6, the internal material is dense and has no defects, and even if it is impacted, no cracks will be generated), which is convenient for visualization and identification.

[0052] Furthermore, an air blowing pipe 331 is fixedly installed at the position corresponding to the discharge barrel 35 on the transfer box 33, and the air blowing pipe 331 is connected to an air pump. During actual feeding, when the push block 341 pushes the magnet 6 into the discharge barrel 35, the upper space of the corresponding discharge barrel 35 in the transfer box 33 is blocked, so that the magnet 6 can be blown downward to increase the falling kinetic energy of the magnet 6. When the magnet 6 falls out of the discharge barrel 35, the air at the bottom of the discharge barrel 35 continues to be blown out, and the surface of the magnet 6 can also be cleaned to prevent debris from adhering to the surface of the magnet 6 and affecting the detection accuracy.

[0053] Refer to the instruction manual Fig.13 The lower barrel 35 is provided with a swivel ring 36 for sliding inside, and an elastic retaining ring 362 is fixedly installed in the inner wall of the swivel ring 36. The elastic retaining ring 362 is a flexible structure, and a boss 361 is fixedly installed on the outer wall of the swivel ring 36. A downward chute 351 is provided in the inner wall of the lower barrel 35. The boss 361 is slidably arranged in the downward chute 351, and an elastic member (such as a spring) for providing an upward elastic force to the boss 361 is provided in the boss 361. When the magnet 6 starts to fall, it first falls into the swivel ring 36 and contacts with the boss 361. Due to the friction between the boss 361 and the boss 361, the magnet 6 The movable swivel ring 36 moves downward, and under the guidance of the downward inclined groove 351, the swivel ring 36 and the magnet 6 rotate, thereby giving the magnet 6 a rotational power. When the boss 361 moves down to the limit, the magnet 6 passes over the elastic retaining ring 362 due to inertia. At this time, the magnet 6 already has a rotation speed, and the debris on its surface moves outward under the action of centrifugal force, achieving an automatic cleaning effect. The rotating magnet 6 has stronger kinetic energy when it falls into the positioning boss 21. After the magnet 6 passes over the swivel ring 36, the swivel ring 36 can automatically rotate upward and reset under the action of the elastic member.

[0054] It should be noted that, although the solution provided in this embodiment only detects the upper surface of the magnet 6, according to the same principle, another set of detection equipment can be set up, and the magnet 6 can be flipped with the help of a flipping device to detect both sides of the magnet 6.

[0055] Refer to the instruction manual Fig.16 The present invention also provides a method for detecting surface defects of a magnet, comprising the following steps: Step 1: Place multiple magnets 6 that have been magnetized into a columnar shape into the storage barrel 32, and push them into the discharge barrel 35 by the push block 341 to make them fall and land on the corresponding positioning boss 21 to complete the loading; Step 2: The magnet 6 is driven by the conveying structure 2 to move, and stops when it moves to the bottom of the closed pressing cylinder 51. The closed pressing cylinder 51 falls and docks with the positioning boss 21. The injection pump injects the pigment liquid into the pigment cavity 511, so that the liquid level of the pigment liquid overflows the upper surface of the magnet 6 for coloring; Step 3: Control the liquid extraction pump to extract the pigment liquid in the pigment chamber 511, and then control the closed pressure cylinder 51 to move upward; Step 4: The conveying structure 2 continues to drive the magnet 6 to move, and the visual recognition detection system 4 performs image recognition on the upper surface of the colored magnet 6 to determine whether there is an area on the surface that cannot be colored due to protrusions; Step 5: The magnet 6 passes through the scraper structure 7 to scrape off the paint on its upper surface; Step 6: The visual recognition detection system 4 performs image recognition again on the upper surface of the magnet 6 after the paint is scraped off, to determine whether there are areas on the surface where the paint cannot be scraped off due to cracks and pits.

[0056] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A magnet surface defect detection device, characterized in that: The machine base (1) comprises a conveying structure (2) arranged on the machine base (1), and a feeding component (3), a coloring component (5) and a visual recognition detection system (4) arranged in sequence on the machine base (1) along the conveying direction of the conveying structure (2); The conveying structure (2) is provided with a positioning boss (21), the positioning boss (21) is provided with a positioning groove for accommodating the magnet (6), the loading assembly (3) is used to place the magnet (6) into the positioning boss (21), and the visual recognition detection system (4) is used to perform visual detection on the upper surface of the magnet (6); The coloring component (5) comprises a closed pressing cylinder (51), wherein the closed pressing cylinder (51) is slidably mounted above the machine base (1); when the positioning boss (21) reaches below the closed pressing cylinder (51), the closed pressing cylinder (51) descends and is plugged into the positioning boss (21); a pigment cavity (511) is formed between the closed pressing cylinder (51) and the magnet (6); a pigment channel (512) and an input / output pipe (513) are provided on the closed pressing cylinder (51); the pigment channel (512) is connected to the pigment cavity (511) and the input / output pipe (513); the input / output pipe (513) is connected to an injection pump and a liquid extraction pump respectively through a tap, wherein the injection pump is used to inject pigment liquid into the pigment cavity (511), and the liquid extraction pump is used to extract the pigment liquid from the pigment cavity (511); The machine base (1) is also provided with a scraper structure (7), and the scraper structure (7) cooperates with the upper surface of the magnet (6).

2. A magnet surface defect detection device according to claim 1, characterized in that: The conveying structure (2) is a conveying belt. The positioning boss (21) and the conveying belt are integrally formed. When the magnet (6) is placed in the positioning groove, the top plane of the positioning boss (21) is lower than the upper surface of the magnet (6). The closed pressing cylinder (51) is connected to the machine base (1) via a mounting frame. The mounting frame is fixedly mounted on the machine base (1). The closed pressing cylinder (51) is slidably mounted on the mounting frame. A lifting drive (52) is also fixedly mounted on the mounting frame. The closed pressing cylinder (51) is fixedly mounted on the output end of the lifting drive (52).

3. A magnet surface defect detection device according to claim 2, characterized in that: The visual recognition detection system (4) comprises a CCD camera (41) and a light source (42), wherein the light source (42) is used to illuminate the colored magnet (6), and the CCD camera (41) is used to capture an image of the upper surface of the magnet (6). The CCD camera (41) and the light source (42) are fixedly mounted on a mounting frame.

4. A magnet surface defect detection device according to claim 3, characterized in that: A liquid level sensor (514) is provided in the pigment chamber (511) in an area corresponding to the upper surface of the magnet (6); an overflow hole (515) is provided on the side wall of the pigment chamber (511); the overflow hole (515) is connected to the outside of the closed pressure cylinder (51); the overflow hole (515) is provided above the upper surface of the magnet (6); a heater (516) is fixedly installed in the pigment chamber (511); an exhaust chamber (517) is provided at a position corresponding to the overflow hole (515) outside the closed pressure cylinder (51); an exhaust pipe (518) is fixedly installed on the exhaust chamber (517); and the exhaust pipe (518) is connected to a vacuum pump.

5. A magnet surface defect detection device according to claim 4, characterized in that: An inner support frame (11) is provided in the machine base (1), the inner support frame (11) is arranged in contact with the conveying structure (2), and a receiving groove (12) is provided in the inner support frame (11) at a position below the closed pressure cylinder (51), a turntable (13) is rotatably installed in the receiving groove (12), a driving motor (15) is installed on the inner support frame (11), the driving motor (15) is used to drive the turntable (13) to rotate, a first adsorption magnetic component (14) is fixedly installed in the turntable (13), the first adsorption magnetic component (14) is eccentrically arranged with the turntable (13), and the first adsorption magnetic component (14) is used to magnetically adsorb the magnet (6).

6. A magnet surface defect detection device according to claim 5, characterized in that: A plurality of fixed protrusions (121) are fixedly mounted on the inner wall of the accommodating groove (12), and an elastic protrusion (131) is fixedly mounted on the side wall of the rotating disk (13); when the rotating disk (13) rotates, the elastic protrusions (131) and the fixed protrusions (121) touch each other to generate vibration.

7. A magnet surface defect detection device according to claim 6, characterized in that: The loading assembly (3) comprises a support frame (31), a material storage barrel (32) and a material discharge barrel (35); the support frame (31) is fixedly mounted on the machine base (1); the material storage barrel (32) is fixedly mounted on the support frame (31); a material discharge barrel (35) is also fixedly mounted in the support frame (31); a transfer box (33) is provided between the material discharge barrel (35) and the material storage barrel (32); a pusher (34) is fixedly mounted on the transfer box (33); a push block (341) is slidably mounted in the transfer box (33); and the push block (341) is fixedly mounted on the output end of the pusher (34).

8. A magnet surface defect detection device according to claim 7, characterized in that: A second adsorption magnetic component (16) is fixedly mounted on the inner support frame (11) at a position corresponding to the lower barrel (35), and the second adsorption magnetic component (16) is used to adsorb the magnet (6). An air blowing pipe (331) is fixedly mounted on the transfer box (33) at a position corresponding to the lower barrel (35), and the air blowing pipe (331) is connected to an air pump.

9. A magnet surface defect detection device according to claim 8, characterized in that: A swivel ring (36) is slidably arranged inside the lower barrel (35), an elastic retaining ring (362) is fixedly installed in the inner wall of the swivel ring (36), and the elastic retaining ring (362) is a flexible structure. A protruding column (361) is fixedly installed on the outer wall of the swivel ring (36), a downward-inclined slide groove (351) is arranged in the inner wall of the lower barrel (35), the protruding column (361) is slidably arranged in the downward-inclined slide groove (351), and an elastic member for providing an upward elastic force to the protruding column (361) is arranged in the protruding column (361).

10. A detection method of the magnet surface defect detection device as claimed in claim 9, characterized in that: The following steps are involved: Step 1: Place multiple magnets (6) that have been magnetized to form a columnar shape into a storage barrel (32), and push them into a discharge barrel (35) by a push block (341) to make them fall and land on corresponding positioning bosses (21) to complete the loading; Step 2: The conveying structure (2) drives the magnet (6) to move, and stops when it moves to the bottom of the closed pressing cylinder (51), the closed pressing cylinder (51) falls and docks with the positioning boss (21), and the injection pump injects the pigment liquid into the pigment chamber (511), so that the liquid level of the pigment liquid overflows the upper surface of the magnet (6) to perform coloring; Step 3: Control the liquid extraction pump to extract the pigment liquid in the pigment chamber (511), and then control the closed pressing cylinder (51) to move upward; Step 4: The conveying structure (2) continues to drive the magnet (6) to move, and the visual recognition detection system (4) performs image recognition on the upper surface of the colored magnet (6) to determine whether the surface has an area that cannot be colored due to protrusions; Step 5: The magnet (6) passes through the scraper structure (7) to scrape off the paint on its upper surface; Step 6: The visual recognition detection system (4) performs image recognition again on the upper surface of the magnet (6) after the paint is scraped off, to determine whether there are areas on the surface where the paint cannot be scraped off due to cracks and pits.

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