Visual inspection device

Abstract

The invention discloses a visual detection device, which is used for solving the problems of visual shielding and low detection efficiency caused by a jig to a product. The visual inspection device comprises a carrying table, a positioning jig, a jacking mechanism, a rotating mechanism and a visual inspection mechanism, the positioning jig is provided with a positioning seat with a positioning hole and a bearing piece arranged in the positioning hole in a penetrating mode, and the bearing piece and the positioning hole form a positioning groove for containing a product. A first jacking part and a second jacking part of the jacking mechanism respectively act on the positioning seat and the bearing piece, so that the jacked product is completely exposed from the positioning jig, and the visual inspection mechanism is used for carrying out image acquisition on the jacked product; and the rotating mechanism is used for driving the jacked positioning jig to rotate so as to quickly switch the to-be-detected products on the positioning jig to the to-be-detected direction in sequence. According to the invention, through linkage of jacking and rotation, non-shielding, efficient and continuous visual inspection of a plurality of small-specification products is realized.

Description

Technical Field

[0001] This invention relates to the field of industrial automation technology, and in particular to a visual inspection device for inspecting multiple small-sized products. Background Technology

[0002] In industrial automated production, visual inspection of multiple small-sized products (such as small sealing rings and precision electronic components) is a key step in ensuring product quality. The common practice is to place these products in a fixture that at least partially surrounds them, such as a fixture with positioning grooves, and then transport the fixture carrying the products to the visual inspection station via a conveyor mechanism.

[0003] However, due to the presence of positioning grooves on the fixture and the fact that the groove walls usually have a certain height, when the light source of the vision inspection system shines on the product, the side walls of the positioning grooves will inevitably cause occlusion or reflection, forming interfering shadows or reflected light spots on the product. This will seriously interfere with the inspection camera's accurate capture and identification of defects such as burrs, scratches, dents, and uneven plating on the product, creating blind spots in the inspection. Summary of the Invention

[0004] The purpose of this application is to provide a visual inspection device for batch inspection of visual defects in small-sized products, which adopts the following technical solution:

[0005] A visual inspection device, comprising:

[0006] Platform;

[0007] A positioning fixture is disposed on the platform. The positioning fixture includes a positioning base and a plurality of support members that can move vertically relative to the positioning base. The positioning base can be raised from a first position to a second position relative to the platform. The positioning base forms an anti-rotation engagement with the platform in the first position and disengages from the anti-rotation engagement with the platform in the second position. The positioning base has a plurality of positioning holes in the circumferential direction, and the support members are correspondingly inserted into the positioning holes. The support members are used to support the product, and the upper end face of the support member forms a positioning groove with the positioning holes to accommodate and at least partially surround the product. One of the support members is located in the position to be tested.

[0008] A lifting mechanism, disposed below the positioning fixture, includes a first lifting member and a second lifting member; the first lifting member acts on the positioning seat and lifts the positioning seat from the first position to the second position; the second lifting member acts on the support member and lifts the support member relative to the platform, so that the upper surface of the support member is flush with or extends beyond the positioning seat;

[0009] A rotating mechanism is configured to drive the positioning fixture to rotate after the positioning seat is lifted to the second position, so as to sequentially switch the different supports to the position to be detected;

[0010] A visual inspection mechanism is configured to acquire images of the product located on the support at the inspection position.

[0011] By adopting the above technical solution, before the product is inspected by the vision inspection mechanism, the product is lifted from the positioning slot until its bottom surface is flush with or exceeds the top surface of the positioning seat. This ensures that when the light source of the vision inspection mechanism shines on the product, the positioning seat will not obstruct or reflect light onto the product, thereby optimizing the inspection field of view, reducing shadows or light spot interference during product inspection, and improving the accuracy of the inspection results. Furthermore, the positioning seat used in this solution can hold multiple products in the circumferential direction. After the positioning seat is lifted to a second position that can rotate relative to the platform, and after the first product in the inspection position is inspected, the positioning seat is rotated sequentially to place the remaining products in the inspection position, thus shortening the cycle time.

[0012] Furthermore, the lifting mechanism includes a lifting drive member, wherein the first lifting member and the second lifting member are simultaneously lifted by the lifting drive member; the second lifting member is higher than the first lifting member in the vertical direction, and the second lifting member contacts and lifts its target object before the first lifting member.

[0013] By adopting the above technical solution, the first lifting component and the second lifting component are lifted synchronously by the same driving component. By using the height difference between the first lifting component and the second lifting component in the vertical direction and the time difference between the positioning seat and the support component being contacted and lifted, the number of driving components and lifting steps are reduced, and the structure of the visual inspection device is simplified.

[0014] Preferably, the second lifting member includes a plurality of lifting columns, each of which is correspondingly provided with a positioning hole and is configured to extend into the corresponding positioning hole to lift the support member; the rotating mechanism is configured to drive the lifting columns to rotate, and the lifting columns and the positioning holes are clearance-fitted.

[0015] Using the above technical solution, the rotating mechanism drives the lifting column to rotate, and the lifting column transmits torque by extending into the positioning hole, thereby driving the positioning fixture to rotate. That is, the lifting column integrates the functions of lifting the supporting column and rotating the positioning fixture, without the need for an additional rotating transmission structure acting on the positioning fixture, which helps to simplify the structure of the device.

[0016] Furthermore, the top end of the lifting column and the bottom end of the positioning hole are provided with guide structures; or, the mating surfaces of the lifting column and the positioning hole are provided with wear-resistant coatings; or, the top end of the lifting column and the bottom end of the positioning hole are provided with guide structures, and the mating surfaces of the lifting column and the positioning hole are provided with wear-resistant coatings. Adopting the above technical solutions helps to reduce the risk of alignment impact and wear during the process of the lifting column extending into the positioning hole.

[0017] Preferably, one of the positioning seat and the platform is provided with a positioning pin, and the other is provided with a pin hole; when the positioning seat is in the first position, the positioning pin engages with the pin hole; when the positioning seat is in the second position, the positioning pin disengages from the pin hole.

[0018] Furthermore, the number of pin holes is the same as the number of positioning holes, and both the pin holes and the positioning holes are evenly arranged along the circumference of the positioning seat. Using the above technical solution, the positioning fixture can be driven to rotate any number of times, and the positioning seat can be lowered into the platform, with the two achieving rotational locking again through the pin holes.

[0019] Preferably, the platform has a fixture hole; the positioning seat includes a central shaft and a positioning platform; the central shaft is inserted into the fixture hole and can rotate relative to the platform and slide vertically. By adopting the above technical solution, the positioning seat can be stably raised and lowered and rotated relative to the platform.

[0020] Furthermore, the platform is a turntable, and the turntable is provided with a fixture hole for accommodating the positioning fixture. The turntable is provided with two or more vision detection units in the circumferential direction. The vision detection unit includes the fixture hole and the positioning fixture, the lifting mechanism, the rotating mechanism and the vision detection mechanism, which are arranged corresponding to the fixture hole.

[0021] By adopting the above technical solution, the automated circulation of positioning fixtures and continuous operation of multiple stations can be realized, the positioning error of manual placement of positioning fixtures can be reduced, and parallel detection of two or more visual inspection areas can be achieved, thus doubling the detection efficiency.

[0022] Furthermore, the visual inspection mechanism includes a first inspection mechanism positioned above the positioning fixture and a second inspection mechanism parallel to the first inspection mechanism in the vertical direction; the first inspection mechanism includes a first light source and a first camera for inspecting the product from a vertical direction; the second inspection mechanism includes a second light source, a second camera, and a light source reflector, the light source reflector being disposed on the horizontal side of the positioning fixture and directly below the second light source and the second camera in the vertical direction; the reflective surface of the light source reflector faces the second light source and the second camera in the vertical direction and faces the side of the product to be inspected on the positioning fixture in the horizontal direction.

[0023] By adopting the above technical solution, products can be inspected from two perspectives simultaneously, and the second inspection mechanism is set parallel to the first inspection mechanism, which can effectively reduce the lateral space of the visual inspection device. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of a visual detection device in one embodiment of this application;

[0025] Figure 2 This is a schematic diagram of a positioning fixture containing a product in one embodiment of this application;

[0026] Figure 3 This is a cross-sectional view showing a positioning fixture containing a product in one embodiment of this application;

[0027] Figure 4 This is a schematic diagram of the lifting mechanism and the rotating mechanism in one embodiment of this application;

[0028] Figure 5 This is a schematic diagram of the lifting mechanism and the rotating mechanism in one embodiment of this application;

[0029] Figure 6 This is a cross-sectional view of the positioning fixture in a first position according to one embodiment of this application;

[0030] Figure 7 This is a cross-sectional view of the positioning fixture in a second position according to one embodiment of this application;

[0031] Figure 8 This is a schematic diagram of a vision inspection device with two vision inspection stations in one embodiment of this application;

[0032] Figure 9 This is an exploded view of a positioning fixture and a platform in one embodiment of this application;

[0033] Figure 10 This is a top view of a platform carrying multiple positioning fixtures in one embodiment of this application;

[0034] Figure 11 This is a schematic diagram of a visual inspection mechanism in one embodiment of this application.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1. Platform; 11. Positioning pin; 12. Fixture hole;

[0037] 2. Positioning fixture; 21. Positioning seat; 211. Positioning hole; 212. Positioning groove; 213. Pin hole; 214. Central shaft part; 215. Positioning table; 22. Supporting component; 221. Supporting part; 222. Guide rod part;

[0038] 3. Lifting mechanism; 31. First lifting component; 32. Second lifting component; 33. Lifting drive component;

[0039] 4. Rotating mechanism; 41. Rotating drive component; 42. Shaft; 43. Coupling; 44. Bearing;

[0040] 5. Visual inspection mechanism; 5a. First inspection mechanism; 5b. Second inspection mechanism; 51. Light source; 51a. First light source; 51b. Second light source; 52. Camera; 52a. First camera; 52b. Second camera; 53. Height adjustment component; 54. Light source reflector;

[0041] 6. Auxiliary installation structure; 61. First fastener; 62. Second fastener; 63. Third fastener;

[0042] 7. Products;

[0043] 8. Indexing drive mechanism. Detailed Implementation

[0044] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0045] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0046] In industrial automated production, visual inspection of small-sized products (such as small sealing rings and precision electronic components) is a crucial step in ensuring product quality. Currently, the common practice is to place these products in a fixture that at least partially surrounds them, such as a fixture with positioning grooves, and then transport the fixture carrying the products to the visual inspection station via a conveyor mechanism. However, due to the presence of the positioning grooves on the fixture, and the fact that the groove walls usually have a certain height, when the light source of the visual inspection system illuminates the product, the side walls of the positioning grooves inevitably cause occlusion or reflection, forming interfering shadows or reflected light spots on the product. This severely interferes with the inspection camera's accurate capture and identification of defects such as burrs, scratches, dents, and uneven plating on the product, creating blind spots in the inspection.

[0047] To address this, the present invention provides a visual inspection device that, through mechanical linkage, lifts the product to fully expose it before inspection and enables rapid switching between multiple products to be inspected by rotating a fixture, thereby simultaneously solving the problems of blind spots and low inspection efficiency in visual inspection.

[0048] Reference Figure 1 This application discloses a visual inspection device, including a platform 1, a positioning fixture 2, a lifting mechanism 3, a rotating mechanism 4, and a visual inspection mechanism 5. The platform 1, lifting mechanism 3, rotating mechanism 4, and visual inspection mechanism 5 are securely mounted on a base (not shown in the figure) via an auxiliary mounting structure 6. (See also...) Figures 2 to 4 The positioning fixture 2 has a positioning seat 21 with a positioning hole 211 and a support member 22 passing through the positioning hole 211. The support member 22 and the positioning hole 211 form a positioning groove 212 for accommodating the product 7. The first lifting part 31 and the second lifting part 32 of the lifting mechanism 3 act on the positioning seat 21 and the support member 22 respectively, so that the product 7 is completely exposed from the positioning fixture 2 after lifting. The visual inspection mechanism 5 is used to acquire images of the lifted product 7. The rotating mechanism 4 is used to drive the lifted positioning fixture 2 to rotate, so as to quickly switch the products 7 to be inspected on the positioning fixture 2 to the inspection position in sequence. The lifting mechanism 3, the rotating mechanism 4 and the visual inspection mechanism 5 are all electrically connected to a control system (not shown in the figure) and can receive its instructions to execute corresponding coordinated actions.

[0049] Specifically, refer to Figures 1 to 3A positioning fixture 2 is mounted on a platform 1 to support and position the product 7 to be inspected. The positioning fixture 2 includes a disc-shaped positioning seat 21 and multiple support members 22. In its initial, unlifted state, the positioning seat 21 is in its first position, with its bottom supported by the platform 1, forming an anti-rotation connection. The positioning seat 21 has multiple positioning holes 211 along its circumference; preferably, these holes are evenly arranged circumferentially. Each support member 22 is a columnar rod, including a larger diameter support portion 221 at the top and a smaller diameter guide rod portion 222 at the bottom. The support members 22 are correspondingly inserted into the positioning holes 211 and can move vertically relative to the positioning seat 21. To prevent the support member 22 from falling out of the hole under gravity or vibration, the positioning hole 211 is preferably a stepped hole or has a structure with an inwardly protruding step. Specifically, its upper hole diameter D1 is larger than its lower hole diameter D2, thereby forming an annular support step surface inside the hole. The diameter of the support portion 221 is adapted to the upper hole diameter D1 of the positioning hole 211, and the diameter of the guide rod portion 222 is adapted to the lower hole diameter D2 of the positioning hole 211. In the initial state before lifting, each support member 22 hangs down naturally under the action of gravity, and the lower end face of its support portion 221 rests on the support step surface inside the positioning hole 211, thereby being reliably supported; and the upper end face of each support member 22 forms a positioning groove 212 with the hole wall of the through positioning hole 211. The positioning groove 212 is used to accommodate and at least partially surround the product 7 to be inspected.

[0050] The lifting mechanism 3 is located below the positioning fixture 2, as shown in the reference. Figures 4 to 5 The lifting mechanism 3 includes a first lifting member 31 and a second lifting member 32, and is fixed to the base by a first fixing member 61. Meanwhile, referring to... Figures 6 to 7 The first lifting member 31 acts on the bottom surface of the positioning seat 21 to lift it from a first position where it is anti-rotationally connected to the platform 1 to a second position where it is completely detached from the platform 1, and in this second position, the anti-rotational connection between the positioning seat 21 and the platform 1 is released. The second lifting member 32 is configured to act on the bottom end of the support member 22 to lift the support member 22 and the product 7 located on the support member 22 upward, so that the upper end surface of the support member 22 is flush with or extends beyond the upper surface of the positioning seat 21, and the surface and circumference of the product 7 are fully exposed.

[0051] Reference Figures 4 to 5 The rotating mechanism 4 is located below the positioning fixture 2 and includes a rotating drive 41 (such as a motor), a rotating shaft 42, a coupling 43, and a bearing 44, and is fixed to the base by a second fixing member 62. One end of the coupling 43 is connected to the output shaft of the motor, and the other end is connected to the lower end of the rotating shaft 42; the rotating shaft 42 is mounted through the bearing 44, and its upper end is operably coupled to the positioning fixture 2 to transmit rotational torque to the positioning fixture 2, thereby driving the lifted positioning fixture 2 to rotate relative to the platform 1.

[0052] Reference Figure 3 The visual inspection mechanism 5 is mounted above the positioning fixture 2. It includes a light source 51 and a camera 52 and is fixed to the base by a third fastener 63. It is used to inspect the appearance of the product 7 on the lifted support 22, such as defects such as burrs, scratches, dents, and uneven plating.

[0053] In this embodiment, as preparation for visual inspection, the positioning fixture 2 carrying the product 7 is installed at the visual inspection station of the platform 1, and one of the supports 22 and the product 7 on it are positioned directly below the camera 52 or the light source 51, i.e., the inspection position. Thus, the optical axis of the lens of the camera 52 is directly or indirectly oriented toward the hole of the positioning groove 212 or the support 22 in the inspection position.

[0054] When using the vision inspection device to inspect product 7, firstly, the lifting mechanism 3 is activated to lift the positioning fixture 2 as a whole, so that the bottom surface of product 7 on the support 22 is higher than or flush with the upper surface of the positioning seat 21. While maintaining the lifting state, the vision inspection mechanism 5 is activated to acquire an image of the first product 7 located in the inspection position. After completing one image acquisition, the control system sends a command to the rotation mechanism 4, which drives the positioning fixture 2 to rotate, so that the next support 22 rotates to the inspection position; the vision inspection mechanism 5 acquires an image again; this rotation and image acquisition action is repeated until the control system confirms that each rotation is in place through the signal feedback from the sensor, and accumulates the number of products inspected. When the accumulated number is equal to the total number of products on the positioning fixture 2 or the preset number of products to be inspected, the control system determines that the preset inspection task is completed, and controls the lifting mechanism 3 to descend, so that the positioning fixture 2 falls back to the platform 1 and is reset and locked.

[0055] It can be understood that the number of positioning holes 211 and supporting members 22 is set according to actual requirements, and the number of products to be detected that can be accommodated on the positioning fixture 2 corresponds to the number of positioning holes 211 and supporting members 22. Preferably, the number of positioning holes 211 and supporting members 22 is 4, 6, 8, 10, 12, or 16; the product to be detected 7 can be a cylindrical sealing ring. In addition, the relative position of the top surface of the product 7 relative to the top surface of the positioning base 21 before jacking, and the relative position of the bottom surface of the product 7 relative to the top surface of the positioning base 21 after jacking can both be accurately set by adjusting the design parameters of the product and the positioning fixture. Define the height of the product to be detected 7 as a, and define the height of the positioning groove 212 as b; when b≥a, the product 7 is completely accommodated in the positioning groove 212 before starting to be jacked; when b<a, the top of the product 7 protrudes above the top surface of the positioning base 21 before starting to be jacked. Define the height that the first jacking member 31 jacks up the positioning base 21 as h1, and the height that the second jacking member 32 jacks up the supporting member 22 as h2. When h1 + b = h2, the upper end surface of the supporting member 22 is flush with the top surface of the positioning base 21 after jacking; when h1 + b < h2, the upper end surface of the supporting member 22 is higher than the surface of the positioning base 21 after jacking.

[0056] In addition, the jacking actions of the first jacking member 31 and the second jacking member 32 can be carried out synchronously or in a certain order; their driving forces can be the same or different.

[0057] With the above technical solution, before using the vision detection mechanism 5 to detect the product 7, the supporting member 22 is jacked up until its bottom surface is flush with or exceeds the top surface of the positioning base 21, ensuring that when the light source 51 of the vision detection mechanism 5 irradiates on the product 7, the positioning base 21 will not block or reflect the product 7, thereby optimizing the detection field of view, reducing the shadow or light spot interference during product detection, and improving the accuracy of the detection result. In addition, this solution realizes the detection of multiple products at the same station through a simple rotation action, shortening the cycle time.

[0058] Refer to Figure 5The lifting mechanism 3 includes a lifting drive component 33, which is preferably a cylinder or an electric cylinder. The output end of the lifting drive component 33 is rigidly connected to the bottom of the first lifting component 31 directly via a connecting flange or threads. Further, the second lifting component 32 is integrally mounted on the first lifting component 31, or the second lifting component 32 is fixedly connected to the first lifting component 31 and protrudes above the first lifting component 31, for example, the second lifting component 32 is bolted to the first lifting component 31. Thus, the second lifting component 32 and the first lifting component 31 constitute a rigid, integral moving part, and the top surface of the second lifting component 32 is always higher than the top surface of the first lifting component 31, with a fixed height difference between them in the vertical direction. When the piston rod of the lifting drive 33 extends, it pushes the first lifting member 31 connected to it to move upward. The second lifting member 32 fixed to it moves synchronously. Due to the height difference, the second lifting member 32 contacts its target object before the first lifting member 31. Therefore, the support member 22 and the product 7 on it are lifted before the positioning seat 21. Subsequently, the first lifting member 31 contacts and lifts the bottom end of the positioning seat 21. Preferably, the first lifting member 31 is disc-shaped or plate-shaped. By adopting the above technical solution, the first lifting member 31 and the second lifting member 32 are lifted synchronously by the same lifting drive 33. By using the height difference between the first lifting member 31 and the second lifting member 32 in the vertical direction and the time difference between the positioning seat 21 and the support member 22 being contacted and lifted, the number of drive members and lifting steps are reduced, the structure of the visual inspection device is simplified, and costs are reduced.

[0059] Furthermore, the lifting mechanism 3 and the rotating mechanism 4 are integrated into a composite motion module that can realize lifting and rotating functions. The lifting mechanism 3 can be configured to synchronously lift and lower the rotating mechanism 4, the first lifting member 31, and the second lifting member 32 as a whole. The torque of the rotating mechanism 4 is transmitted to the positioning fixture 2 through the first lifting member 31 and the second lifting member 32 in the lifting mechanism 3.

[0060] Specifically, refer to Figures 4 to 5 The lifting drive component 33 is preferably a lifting cylinder, which includes a piston rod that can move in the vertical direction and a cylinder body mounted on the base via a first fixing member 61. The piston rod of the lifting cylinder is connected to and directly acts on a second fixing member 62. The second fixing member 62 serves as a mounting platform for the rotation and lifting functional modules, such as a support plate. That is, the rotation drive component 41, coupling 43, bearing 44, rotating shaft 42, and the first lifting component 31 are all vertically inserted and fixedly mounted on the support plate. The first lifting component 31 can be anti-rotationally connected to the rotating shaft 42 via a structure such as a waist-shaped pin or spline. The second lifting component 32 includes multiple lifting columns, which are arranged one-to-one with the positioning holes 211 and are configured such that the lifting columns at least partially extend into the positioning holes 211 at the end of the lifting process.

[0061] Therefore, when the control system controls the lifting drive 33 to move, the piston rod extends, pushing the entire support plate and all the components it supports (including the rotary drive 41, coupling 43, bearing 44, rotating shaft 42, first lifting component 31, and second lifting component 32) to move vertically as a whole, completing the action of lifting product 7 away from positioning slot 212. When it is necessary to switch products, while the support plate and all the components on it are in the lifted state, the control system sends a command to the rotary drive 41 of the rotating mechanism 4. The torque of the rotary drive 41 is transmitted to the rotating shaft 42 through the coupling 43, and then to the positioning fixture 2 through the first lifting component 31 and the second lifting component 32.

[0062] In some embodiments, to ensure the accuracy of the rotation angle, a servo origin sensor is coaxially mounted on the rotating shaft 42, and the rotation drive 41 is a servo motor. During system initialization or the first product alignment, the control system drives the servo motor to rotate. When the servo origin sensor detects a specific physical reference point (such as a keyway or photoelectric mark) on the rotating shaft 42, it is confirmed as the mechanical origin of the rotation. At this time, the first product to be tested is located in the detection position. Based on this mechanical origin, the control system performs high-precision position and angle control through the pulse signal emitted by the built-in encoder of the servo motor. When rotation switching is required, the control system sends a command to the servo motor to drive the rotating shaft 42 to rotate by a preset number of pulses (corresponding to a preset angle). The encoder provides real-time feedback on the actual position until the feedback value matches the target value, at which point the motor stops precisely to ensure accurate switching of each product to the detection position.

[0063] It is understandable that the preset angle for rotating the positioning fixture 2 is calculated based on the number of positioning holes 211. The calculation method is as follows: if the number of positioning holes 211 is n, then the angle α of each rotation of the positioning fixture 2 can be calculated. For example, if there are 12 positioning holes, the rotation angle α = 30°; if there are 16 positioning holes, the rotation angle α = 22.5°. By adopting the above technical solution, the second lifting member 32 integrates the functions of lifting the supporting column and rotating the positioning fixture 2, eliminating the need for an additional rotating transmission mechanism acting on the positioning fixture 2, which simplifies the device.

[0064] Furthermore, because the lifting column needs to be frequently and precisely inserted into the positioning hole 211, long-term use may cause impact wear or deformation of the column body or the entrance of the positioning hole 211 due to slight alignment deviations. (Refer to...) Figure 6The top of the lifting column is provided with a guide chamfer or rounded corner, and the entrance of the positioning hole 211 is also provided with a corresponding guide slope or chamfer. By setting the above-mentioned guide structure, the risk of alignment impact and wear during the extension process of the lifting column is significantly reduced. Optionally, a wear-resistant coating, such as a Teflon coating or a hard anodized layer, is applied to the mating surface of the lifting column or the inner wall of the positioning hole 211 to extend its service life.

[0065] Furthermore, to ensure precise connection and rapid reset between the positioning fixture 2 and the stage 1 before and after testing, one of the positioning base 21 and the stage 1 is provided with a positioning pin 11, and the other is provided with a pin hole 213. (Refer to...) Figures 6 to 7 In some specific embodiments, the pin hole 213 is located on the bottom surface of the positioning seat 21. When the positioning seat 21 is in the first position, the positioning pin 11 automatically inserts into the pin hole 213 under the action of gravity and guidance, forming a reliable anti-rotation connection and circumferential positioning. When the positioning seat 21 is lifted to the second position, the positioning pin 11 completely disengages from the pin hole 213, and the positioning fixture 2 can rotate relative to the platform 1.

[0066] To ensure that the positioning fixture 2 can quickly and accurately reset and lock after any number of rotations, the number of pin holes 213 is equal to the number of positioning holes 211, or it can be 2, 3, or other integer multiples thereof. Increasing the multiple can reduce the weight of the positioning fixture 2. Furthermore, the pin holes 213 and positioning holes 211 are evenly arranged along the circumference of the positioning seat 21. This ensures that after the positioning fixture 2 rotates any number of times in the lifting state or completes the visual inspection of any number of products, when the positioning seat 21 descends, one pin hole 213 will rotate to a position directly opposite the positioning pin 11, thereby locking the positioning seat 21 and the platform 1. Thus, there is no need to drive the positioning fixture 2 to rotate to find the initial zero point orientation.

[0067] This solution demonstrates significant advantages in multi-station parallel inspection systems. For example, when the vision inspection device is configured with m vision inspection stations that can work synchronously, each rotation of the positioning fixture 2 can simultaneously complete the inspection of m products. The calculation logic for the number of rotations required to drive the positioning fixture 2 to inspect all products, given that the base 21 has n positioning holes 211, is as follows: The first inspection requires no rotation to complete the inspection of the first m products; thereafter, each rotation completes the inspection of the next batch of m products. Therefore, when n is divisible by m, the total number of rotations c required to complete the inspection of all n products is: c = (n / m) - 1.

[0068] Reference Figure 8In a preferred embodiment, m = 2 visual inspection stations are set up, and the number of positioning holes 211 on the positioning base 21 is n = 16. After the initial lifting, the two stations can simultaneously inspect products (rotation count c = 0); subsequently, two new products can be inspected simultaneously with each rotation. According to the above formula, only c = (16 ÷ 2) - 1 = 7 rotations are needed for the two stations to collaboratively complete the inspection of all 16 products. After the inspection is completed, the positioning fixture 2 descends. At this time, due to the sufficient number of pin holes 213 (16 in this case), regardless of the angle at which it stops, the positioning pin 11 can immediately insert into the corresponding pin hole 213, achieving precise and rapid reset and locking, preparing for the next inspection cycle.

[0069] Reference Figure 9 To ensure that the positioning seat 21 can stably rise, fall, and rotate relative to the platform 1, the platform 1 is provided with a fixture hole 12. The positioning seat 21 includes a central shaft portion 214 and a positioning platform 215. The central shaft portion 214 and the positioning platform 215 can be an integral structure or a separate structure that is coaxial and fixedly connected. The positioning platform 215 is located above the platform 1 and is used to open a positioning hole 211 to accommodate the support member 22. The central shaft portion 214 is cylindrical, and its diameter d1 is slightly smaller than the inner diameter d2 of the fixture hole 12 to achieve a clearance fit within the fixture hole 12 of the platform 1. Thus, the outer cylindrical surface of the central shaft portion 214 and the inner wall of the fixture hole 12 form a sliding pair, which ensures that the central shaft portion 214 can slide freely (i.e., rise and fall) in the vertical direction without jamming, and effectively restricts its swing or sway in any direction in the horizontal plane, thereby ensuring that the positioning seat 21 can stably rise and fall relative to the platform 1. Meanwhile, the mating surface between the central shaft portion 214 and the fixture hole 12 also constitutes the radial support bearing surface when the positioning seat 21 rotates. When the positioning seat 21 is lifted to the second position and the positioning pin 11 is disengaged from the pin hole 213, when the rotating mechanism 4 drives the positioning fixture 2 to rotate, the outer wall of the central shaft portion 214 and the inner wall of the fixture hole 12 constrain each other, so that the rotation axis remains stable, reducing the radial runout or eccentricity generated by the positioning seat 21 during rotation, thereby ensuring that the positioning seat 21 rotates stably relative to the platform 1.

[0070] To achieve automated and efficient flow inspection of the positioning fixture 2, in some embodiments, the stage 1 is a turntable. (See reference...) Figure 1 and Figure 10The turntable is driven by a high-precision indexing drive mechanism 8 (such as a cam divider) and can perform precise intermittent rotation around its central axis. Multiple fixture holes 12 are spaced at equal angles along the circumference of the turntable, each accommodating a positioning fixture 2. Around the circumference of the turntable, a loading station, one or more vision inspection stations, and a unloading station are sequentially arranged. At the vision inspection station, a complete vision inspection unit, including a lifting mechanism 3, a rotating mechanism 4, and a vision inspection mechanism 5, is fixedly installed. Through the intermittent rotation of the turntable, the positioning fixtures 2 can be automatically transported to each station sequentially, completing the automated process of loading, inspection, and unloading. By adopting the above technical solution, the positional and angular deviations of manually placed positioning fixtures 2 are reduced, ensuring the consistency of the inspection benchmark. Furthermore, the turntable layout has high integration and saves space.

[0071] Further, refer to Figure 8 To improve inspection efficiency, in some embodiments where the platform 1 is a turntable, two or more vision inspection units capable of simultaneous inspection are provided. In a preferred embodiment, the turntable is equipped with two sets of positioning fixtures 2, lifting mechanisms 3, rotating mechanisms 4, and vision inspection mechanisms 5 along its circumference, and these are respectively positioned on two vision inspection stations to form corresponding vision inspection units. The lifting, rotating, image acquisition, and judgment actions of these two sets of vision inspection units are all independently controlled by the control system and can be executed synchronously, thereby performing independent lifting, rotating, and vision inspection operations on the products on the positioning fixtures 2 of the two vision inspection units, thus doubling the inspection efficiency.

[0072] Reference Figure 8 To adapt to the inspection needs of different products and ensure clear imaging and inspection accuracy, in some embodiments, the visual inspection mechanism 5 is equipped with a height adjustment component 53. The height adjustment component 53 is configured to adjust the vertical position of either or both of the camera 52 and the light source 51 relative to the stage 1. Preferably, a lead screw and nut are used as the height adjustment component 53. This module includes a lead screw driven by a stepper motor or a servo motor, a nut slider that cooperates with it, and a linear guide rail. Either or both of the camera 52 and the light source 51 are fixedly mounted on the nut slider. The control system can precisely control the lifting stroke of the nut slider through the drive motor, thereby achieving precise adjustment of the focal length of the camera 52 or the illumination angle of the light source 51.

[0073] To achieve simultaneous and comprehensive inspection of the top and sides of product 7, while minimizing installation space, refer to Figure 11In some embodiments, the visual inspection mechanism 5 includes a first inspection mechanism 5a positioned above the positioning fixture 2 and a second inspection mechanism 5b parallel to the first inspection mechanism 5a in the vertical direction. The first inspection mechanism 5a is located closer to the product 7 and includes a first light source 51a and a first camera 52a. The first light source 51a is preferably a ring light source or a coaxial light source, arranged around the lens of the first camera 52a to provide uniform illumination to the top surface and upper edge of the product 7. The optical axis of the first camera 52a is perpendicular to the table surface of the stage 1 or the top surface of the product 7, and is used to take vertically downward images to acquire images of the top surface and a portion of the upper side surface of the product 7. The second inspection mechanism 5b includes a second light source 51b, a second camera 52b, and a light source reflector 54. The second light source 51b is arranged around the lens of the second camera 52b. The light source reflector 54 is disposed on the horizontal side of the positioning fixture 2 and is located directly below the second light source 51b and the second camera 52b in the vertical direction. The reflective surface of the light source reflector 54 faces the second light source 51b and the second camera 52b in the vertical direction and faces the side of the product 7 to be inspected on the positioning fixture 2 in the horizontal direction. The optical axis of the second camera 52b is initially perpendicular to the table surface of the stage 1. The light emitted by the second light source 51b is deflected by the light source reflector 54 at a specific angle (e.g., 90°) to become a horizontal light path illuminating the side of the product 7. The light reflected back from the side of the product 7 is deflected by the same light source reflector 54 and enters the lens of the second camera 52b, thereby realizing the horizontal inspection of the side of the product 7. Preferably, the light source reflector 54 can be a right-angle prism, a plane mirror, or a special mirror with a coating.

[0074] Therefore, if it is necessary to inspect the side of the product, it is no longer necessary to place the visual inspection mechanism 5 on the side horizontally. By arranging the two visual inspection mechanisms vertically and parallelly and reflecting the light path, the lateral space of the visual inspection device can be effectively reduced, thus achieving the compactness and modularity of the device.

[0075] When performing visual inspection using the visual inspection device of this application, the following steps are included:

[0076] Positioning preparation: Place the positioning fixture in the visual inspection area of ​​the visual inspection mechanism, wherein a product is positioned in the positioning slot, and a support and the product on it are located directly below the camera or light source, i.e. the inspection position. Thus, the optical axis of the camera lens is directly or indirectly oriented toward the positioning slot / support located at the inspection position.

[0077] Lifting and positioning fixture: Activate the lifting mechanism so that the first lifting member acts on the bottom surface of the positioning seat, lifting it from the first position where it is anti-rotationally engaged with the platform to the second position where it can rotate freely; the second lifting member acts on the bottom end of the support member and lifts the support member and the product on it upward so that the upper surface of the support member is flush with or exceeds the positioning seat, and the product is fully exposed from the positioning groove.

[0078] Image acquisition: Using a visual inspection mechanism to acquire images of the product on the support component in the position to be inspected;

[0079] Rotary positioning fixture: With the lifting mechanism in the lifting state, the rotating mechanism is started; the rotating drive component drives the entire lifting positioning fixture to rotate around its vertical axis by a preset angle through transmission components such as the rotating shaft, thereby switching the next support component carrying the product to the position to be tested;

[0080] Determine the number of products to be inspected: Determine whether all products on the positioning fixture have been inspected. Specifically, the control system confirms that each rotation is in place by the signal fed back by the sensor and accumulates the number of products that have been inspected. If the accumulated number is equal to the total number of products on the positioning fixture or the preset number of products to be inspected, the control system determines that the preset inspection task has been completed and executes the reset step; if the accumulated number is less than the total number of products on the positioning fixture or the preset number of products to be inspected, the image acquisition step is executed repeatedly.

[0081] Reset: Control the lifting mechanism to descend, so that the positioning fixture falls back onto the platform.

[0082] By adopting the above technical solution and applying the linkage mechanism of lifting and rotating switching, rapid and continuous testing of multiple products on the fixture is achieved, with a cycle time far lower than that of single-product pick-and-place testing.

[0083] In summary, this invention aims to overcome the shortcomings of existing technologies and provide a visual inspection device. Before the visual inspection mechanism inspects a product, it lifts the product from the positioning slot until its bottom surface is flush with or exceeds the top surface of the positioning seat. This ensures that when the light source of the visual inspection mechanism illuminates the product, the positioning seat will not obstruct or reflect light onto the product, thereby optimizing the inspection field of view, reducing shadows or light spot interference during product inspection, and improving the accuracy of the inspection results. Furthermore, this solution uses a positioning seat with multiple products arranged circumferentially. After the positioning seat is lifted to a second position that can rotate relative to the platform, and after the first product in the inspection position is inspected, the positioning seat is rotated sequentially to place the remaining products in the inspection position, thus shortening the cycle time.

[0084] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A visual inspection device, characterized in that, include: Platform; A positioning fixture is disposed on the platform. The positioning fixture includes a positioning base and a plurality of support members that can move vertically relative to the positioning base. The positioning base can be raised from a first position to a second position relative to the platform. The positioning base forms an anti-rotation engagement with the platform in the first position and disengages from the anti-rotation engagement with the platform in the second position. The positioning base has a plurality of positioning holes in the circumferential direction, and the support members are correspondingly inserted into the positioning holes. The support members are used to support the product, and the upper end face of the support member forms a positioning groove with the positioning holes to accommodate and at least partially surround the product. One of the support members is located in the position to be tested. A lifting mechanism is disposed below the positioning fixture, including a first lifting member and a second lifting member; The first lifting member acts on the positioning seat and lifts the positioning seat from the first position to the second position; The second lifting member acts on the support member and lifts the support member upward relative to the platform, so that the upper surface of the support member is flush with or exceeds the positioning seat; A rotating mechanism is configured to drive the positioning fixture to rotate after the positioning seat is lifted to the second position, so as to sequentially switch the different supports to the detection orientation; A visual inspection mechanism is configured to acquire images of the product located on the support at the inspection position.

2. The visual inspection device according to claim 1, characterized in that, The lifting mechanism includes a lifting drive member, wherein the first lifting member and the second lifting member are lifted synchronously by the lifting drive member; the second lifting member is higher than the first lifting member in the vertical direction, and the second lifting member contacts and lifts its target object before the first lifting member.

3. The visual inspection device according to claim 1, characterized in that, The second lifting member includes a plurality of lifting columns, each of which is correspondingly provided with a positioning hole and is configured to extend into the corresponding positioning hole to lift the supporting rotating mechanism. The lifting column and the positioning hole are configured to be clearance-fitted.

4. The visual inspection device according to claim 3, characterized in that, The top end of the lifting column and the bottom end of the positioning hole are provided with guide structures; or The mating surface of the lifting column and the positioning hole is provided with a wear-resistant coating; or The top end of the lifting column and the bottom end of the positioning hole are provided with guide structures, and the mating surfaces of the lifting column and the positioning hole are provided with wear-resistant coatings.

5. The visual inspection device according to claim 1, characterized in that, One of the positioning seat and the platform is provided with a positioning pin, and the other is provided with a pin hole; when the positioning seat is in the first position, the positioning pin engages with the pin hole; when the positioning seat is in the second position, the positioning pin disengages from the pin hole.

6. The visual inspection device according to claim 5, characterized in that, The number of pin holes is the same as the number of positioning holes, and both the pin holes and the positioning holes are evenly arranged along the circumference of the positioning seat.

7. The visual inspection device according to claim 1, characterized in that, The platform is provided with a fixture hole; the positioning seat includes a central shaft and a positioning platform. The central shaft is inserted into the fixture hole, and the central shaft and the fixture hole are configured to have a clearance fit.

8. The visual inspection device according to claim 7, characterized in that, The platform is a turntable, and the turntable is provided with a fixture hole for accommodating the positioning fixture; The turntable is provided with two or more vision detection units in the circumferential direction. The vision detection unit includes the fixture hole and the positioning fixture, the lifting mechanism, the rotating mechanism and the vision detection mechanism corresponding to the fixture hole.

9. The visual inspection device according to claim 1 or 8, characterized in that, The visual inspection mechanism includes a first inspection mechanism positioned above the positioning fixture and a second inspection mechanism parallel to the first inspection mechanism in the vertical direction; The first detection mechanism includes a first light source and a first camera, used to detect products from a vertical direction; The second detection mechanism includes a second light source, a second camera, and a light source reflector. The light source reflector is disposed on the horizontal side of the positioning fixture and is located directly below the second light source and the second camera in the vertical direction. The reflective surface of the light source reflector faces the second light source and the second camera in the vertical direction and faces the side of the product to be detected on the positioning fixture in the horizontal direction.

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