Triangular prism lens defect detecting and sorting device based on machine vision

Abstract

The invention relates to the technical field of lens production, in particular to a triangular prism lens defect detecting and sorting device based on machine vision. The triangular prism lens is conveyed through stepping type carrying operation, compared with a continuous conveying mode, static detection of a triangular prism can be achieved, and the detection precision is improved. By improving the structures such as the supporting groove and the carrying groove of the stepping carrying mechanism, the triangular prism lens can be turned over multiple times in the stepping conveying process, all-directional detection of the triangular prism lens can be completed without configuring a high-cost turning mechanical arm or a turning mechanism with a complex structure, meanwhile, the time cost of turning operation is saved, and the detection efficiency is improved. And the efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of lens production, and in particular to a defect detection and sorting device for triangular prism lenses based on machine vision. Background Art

[0002] Triangular prism lenses are widely used in various optical instruments such as spectrometers and monochromators, and have high requirements for their quality. After processing, the triangular prism lenses need to be inspected for appearance defects on their surfaces, including defect inspection of the edges and cylindrical surfaces. At present, mainly small-scale manual inspection or medium- and large-scale online machine vision inspection is adopted.

[0003] However, manual inspection has problems such as high labor intensity and inability to guarantee accuracy. Online inspection requires setting up complex mechanical structures to perform operations such as flipping the triangular prism lenses for comprehensive inspection, such as multi-degree-of-freedom manipulators, etc. This not only has high costs, but also the time consumed by the flipping operation results in low inspection efficiency. Moreover, online inspection is mostly dynamic inspection, and the inspection accuracy is difficult to meet the high-quality requirements of triangular prism lenses.

[0004] Therefore, the technical personnel in this field are committed to developing a defect detection and sorting device for triangular prism lenses based on machine vision with simple structure, low cost, high efficiency, and high accuracy. Summary of the Invention

[0005] In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is to provide a defect detection and sorting device for triangular prism lenses based on machine vision with simple structure, low cost, high efficiency, and high accuracy.

[0006] To achieve the above object, the present invention provides a defect detection and sorting device for triangular prism lenses based on machine vision, including a feeding component, a detection component, a discharging component arranged in sequence along the conveying direction, and a sorting component for removing defective products arranged at the end of the detection component; the detection component includes: A detection table, on the top surface of which there are a number of horizontally arranged support grooves for supporting triangular prism lenses with their edges or cylindrical surfaces facing downwards; A pair of stepping forks symmetrically arranged on both sides of the detection table respectively, and a number of handling grooves are arranged on the stepping forks for stepwise handling of the triangular prism lenses on each of the support grooves; A camera component for collecting images of the triangular prism lenses to detect appearance defects on their edges and cylindrical surfaces; A driving mechanism for driving the pair of stepping forks to synchronously lift or move horizontally forward and backward, so that the stepping forks form a rectangular movement trajectory.

[0007] Further, the support groove includes a V-shaped support groove. The two tops of the V-shaped support groove horizontally expand outward to form support steps. The included angle of the V-shaped support groove is 60 degrees for supporting a triangular prism lens with its edge facing downwards. The total width of the support steps is adapted to the width of the cylindrical surface of the triangular prism lens for supporting a triangular prism lens with its cylindrical surface facing downwards.

[0008] Further, the handling groove includes several shallow trapezoidal grooves for translating and stepping the triangular prism lens with its cylindrical surface facing downwards, three deep V-shaped grooves for flipping and stepping the triangular prism lens with its cylindrical surface facing downwards, and three deep trapezoidal grooves for flipping and stepping the triangular prism lens with its edge facing downwards. The shallow trapezoidal grooves and the deep V-shaped grooves are alternately arranged in the detection area under the camera assembly.

[0009] Further, in the rising state of the stepping fork, the included angle of the deep V-shaped groove is 60 degrees and its left vertex is located in the left half of the support groove above it. The bottom endpoint of the left waist of the deep trapezoidal groove is aligned with the midline of the support groove above it. The included angles between the waist sides of the support steps and the waist sides of the deep trapezoidal grooves and the vertical direction are both 60 degrees.

[0010] Further, when the stepping fork is in the position of the descending action, each of the handling grooves and each of the support grooves are vertically aligned one by one. The distance between the deep V-shaped groove, the deep trapezoidal groove and the adjacent handling groove on their left is the sum of p and a, and the distance of the rest is p. Wherein, p is the movement step of the stepping fork, and a is half of the width of the cylindrical surface of the triangular prism lens.

[0011] Further, the sorting assembly includes a telescopic mechanism arranged on one side of the detection table and a push plate fixed to its telescopic end. A defective product box is oppositely arranged on the other side of the detection table.

[0012] Further, both the feeding assembly and the discharging assembly adopt conveyor belts.

[0013] Further, flexible pads are arranged on the surfaces of the support groove and the handling groove.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention realizes the conveying of the triangular prism lens through a step-by-step handling operation. Compared with the continuous conveying method, it can realize the static detection of the triangular prism, improving the detection accuracy. Through the improvement of the structures such as the support groove and the handling groove of the step-by-step handling mechanism, multiple flips of the triangular prism lens are realized during the step-by-step conveying process. It is possible to complete the full-round detection of the triangular prism lens without configuring a high-cost flipping manipulator or a flipping mechanism with a complex structure. At the same time, it saves the time cost of the flipping operation and improves the efficiency. Description of the Drawings

[0015] Figure 1 is the overall structural schematic diagram of the present invention; Figure 2 is the structural schematic diagram of the detection component; Figure 3 is Figure 2 the enlarged view at position A in Figure 4 is the schematic diagram of the flipping process of the triangular prism lens; Figure 5 is the schematic diagram of the positional relationship between the support groove and the handling groove; Figure 6 is the schematic diagram of the step-by-step handling process of the triangular prism lens.

[0016] Reference signs: 1. Feeding component; 2. Detection component; 21. Detection table; 22. Step-by-step fork; 23. Support groove; 24. Camera component; 221. Shallow trapezoidal groove; 222. Deep V-shaped groove; 223. Deep trapezoidal groove; 231. V-shaped support groove; 232. Support step; 3. Discharging component; 4. Sorting component; 41. Telescopic mechanism; 42. Pushing plate; 43. Defective product box. Detailed implementation manners

[0017] The following introduces multiple preferred embodiments of the present invention with reference to the accompanying drawings of the specification to make its technical content clearer and easier to understand. The present invention can be embodied in many different forms of embodiments, and the protection scope of the present invention is not limited to the embodiments mentioned in the text.

[0018] In the accompanying drawings, components with the same structure are denoted by the same reference numerals, and components with similar structures or functions everywhere are denoted by similar reference numerals. The size and thickness of each component shown in the accompanying drawings are arbitrarily shown, and the present invention does not limit the size and thickness of each component. In order to make the illustration clearer, the thickness of some components in the accompanying drawings is appropriately exaggerated.

[0019] Referring to Figure 1 , the triangular prism lens defect detection and sorting device based on machine vision of the present invention includes a feeding component 1, a detection component 2, a discharging component 3 arranged in sequence along the conveying direction, and a sorting component 4 for removing defective products arranged at the end of the detection component; the detection component includes: A detection table 21, on the top surface of the detection table 21, a plurality of horizontally arranged support grooves 23 are opened, and the support grooves 23 are used for supporting the triangular prism lens with the edge facing down or the cylindrical surface facing down; A pair of step-by-step forks 22, the step-by-step forks 22 are symmetrically arranged on both sides of the detection table 21 respectively, and a plurality of handling grooves are arranged on the step-by-step forks 22, and the handling grooves are used for step-by-step handling of the triangular prism lenses on each of the support grooves; A camera assembly 24 for collecting images of a triangular prism lens to detect appearance defects on its edges and cylindrical surfaces; A driving mechanism for driving a pair of the stepping forks 22 to lift or move horizontally forward and backward synchronously, so that the stepping forks 22 form a rectangular movement trajectory.

[0020] The driving mechanism (not shown in the figure) can adopt a combination of a vertical linear module and a horizontal linear module, or a cam - assisted stepping drive method, etc. These common driving designs in the mechanical field will not be elaborated here.

[0021] With the above settings, the stepping fork 22 with a rectangular movement trajectory can lift the triangular prism lens in the support groove 23, move forward by one step pitch and then lower, and place the lifted triangular prism lens in the next support groove 23, realizing the stepping - type handling of the triangular prism lens. During this process, the camera assembly 24 cooperates with the stepping rhythm to collect images and detect the triangular prism lens in the support groove 23 below it. This detection process is actually a static vision detection, which can effectively improve the image quality compared with the detection under the continuous conveying method, and thus improve the detection accuracy.

[0022] For the purpose of detecting all three edges and three cylindrical surfaces of the triangular prism lens, the above - mentioned technical solution is further improved to realize the flipping of the triangular prism lens during the stepping handling process, and it is supported in the support groove in different postures; specifically, the triangular prism lens is flipped by 60 degrees during each stepping handling, and through six times of handling, its three edges and three cylindrical surfaces are successively and alternately oriented towards the camera assembly 24 above for comprehensive visual detection.

[0023] Further, referring to Figures 2 - 3 , the support groove 23 includes a V - shaped support groove 231. Two tops of the V - shaped support groove 231 horizontally expand outwards to form support steps 232. The included angle of the V - shaped support groove 231 is 60 degrees for supporting a triangular prism lens with its edge facing downwards, and the total width of the support steps 232 is adapted to the width of the cylindrical surface of the triangular prism lens for supporting a triangular prism lens with its cylindrical surface facing downwards.

[0024] With the above settings, each support groove 23 can be used to support triangular prism lenses in different postures, improving the applicability of the support groove 23. Of course, since the posture of the triangular prism lens supported by each support groove 23 is certain, each support groove 23 can also be only the V - shaped support groove 231, or only the support step 232.

[0025] Further, referring to Figures 2 - 4, the handling groove includes several shallow trapezoidal grooves 221 for translating and stepping the triangular prism lens with its cylindrical surface facing down, three deep V-shaped grooves 222 for flipping and stepping the triangular prism lens with its cylindrical surface facing down, and three deep trapezoidal grooves 223 for flipping and stepping the triangular prism lens with its edge facing down. The shallow trapezoidal grooves 221 and the deep V-shaped grooves 222 are alternately arranged in the detection area below the camera assembly 24.

[0026] Further, in the rising state of the stepping fork 22, the included angle of the deep V-shaped groove 222 is 60 degrees, and its left vertex is located in the left half of the upper support groove 23 above it. The bottom endpoint of the left waist of the deep trapezoidal groove 223 is aligned with the midline of the upper support groove 23 above it. The waist sides of the support step 232 and the waist sides of the deep trapezoidal groove 223 are both at an angle of 60 degrees with the vertical direction.

[0027] Combined Figure 4 Explain the flipping principle of the deep V-shaped groove 222 and the deep trapezoidal groove 223. Figure 4 The rectangular arrow boxes on the left side in In state a, the stepping fork 22 is ready to rise. In states b-c, the stepping fork 22 is in the rising process. Since the left vertex of the deep V-shaped groove 222 is located in the left half of the downward cylindrical surface of the corresponding triangular prism lens, it pushes the triangular prism lens to flip with its right edge as the rotation axis. For the deep trapezoidal groove 223, since the bottom endpoint of its left waist is aligned with the lower edge of the triangular prism lens above it, it lifts the triangular prism lens with its edge facing down during the rising process and maintains its posture. In state d, the stepping fork 22 has completed the rising action. The triangular prism lens above the deep V-shaped groove 222 has completed a 60-degree flip and is fully supported in the deep V-shaped groove 222 with its edge facing down. The triangular prism lens in an "inverted" state in the deep trapezoidal groove 223 is in an unstable state that is prone to clockwise flipping by 60 degrees. In most cases, it can complete its flip without other operations.

[0028] In state e, the stepping fork 22 has completed the rightward movement. The triangular prism lenses in the deep V-shaped groove 222 and the deep trapezoidal groove 223 are both aligned with the lower support groove 23, so that when the stepping fork 22 descends, the triangular prism lenses can be unloaded into the support groove 23. Among them, even if the triangular prism lens in an "inverted" state in the deep trapezoidal groove 223 fails to complete the flip due to its own instability in state d, then in state e, when the stepping fork 22 completes the rightward movement and "brakes", its inertia will also cause the triangular prism lens to complete the flip due to its instability.

[0029] Further, refer toFigures 5 - 6 When the stepping fork 22 is in the position of the descending movement, each of the handling grooves and each of the supporting grooves 23 are aligned one by one in the vertical direction. The distance between the deep V-shaped groove 222, the deep trapezoidal groove 223 and the adjacent handling groove on their left is the sum of p and a, and the distance of the remaining part is p. Wherein, p is the movement step distance of the stepping fork 22, and a is half of the width of the cylindrical surface of the triangular prism lens.

[0030] Based on the flipping principle of the deep V-shaped groove 222 and the deep trapezoidal groove 223, it can be known that the triangular prism lens moves forward by a distance of a during the flipping process. That is, in the handling groove spacing with the flipping action, in addition to the handling step distance p, it also includes the distance a that the triangular prism lens moves forward by itself during the flipping process.

[0031] See Figure 6 , which shows the action cooperation process between the entire detection table 21 and the stepping fork 22. Figure 6 The rectangular arrow boxes on the left side in [Figure] show the rectangular movement trajectory of the stepping fork 22, and the black dots indicate the positions of the stepping fork 22 on its movement trajectory in the corresponding states.

[0032] Further, the sorting component 4 includes a telescopic mechanism 41 arranged on one side of the detection table 21 and a push plate 42 fixed to its telescopic end. A defective product box 43 is arranged opposite to the other side of the detection table 21.

[0033] When the triangular prism lens with defects after detection is transported to the corresponding supporting groove 23 of the sorting component 4, the telescopic mechanism 41 drives the push plate 42 to push the defective product into the defective product box 43; the qualified products at this place are transported to the discharging component 3 by the end handling groove of the stepping fork 22.

[0034] Further, both the feeding component 1 and the discharging component 3 adopt conveyor belts.

[0035] Further, flexible pads are arranged on the surfaces of the supporting groove 23 and the handling groove. For example, rubber, thin-layer sponge, etc., to prevent damage to the triangular prism lens.

[0036] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations according to the concept of the present invention without creative labor. Therefore, all technical solutions that can be obtained by those skilled in the art in the technical field of the present invention based on the concept of the present invention through logical analysis, reasoning or limited experiments on the basis of the prior art should be within the protection scope determined by the claims.

Claims

1. A triangular prism lens defect detection and sorting device based on machine vision, characterized in that, It includes a feeding component (1), a detection component (2), a discharging component (3) arranged in sequence along the conveying direction, and a sorting component (4) for removing defective products arranged at the end of the detection component; the detection component includes: A detection table (21), on the top surface of the detection table (21), there are a number of horizontally arranged support grooves (23), and the support grooves (23) are used to support a triangular prism lens with its edge facing down or its cylindrical surface facing down; A pair of stepping forks (22), the stepping forks (22) are symmetrically arranged on both sides of the detection table (21) respectively, and there are a number of handling grooves on the stepping forks (22), and the handling grooves are used to step and transport the triangular prism lenses on each of the support grooves; A camera component (24), which is used to collect images of the triangular prism lens to detect appearance defects on its edge and cylindrical surface; A driving mechanism, which is used to drive the pair of stepping forks (22) to lift or move horizontally and retreat synchronously, so that the stepping forks (22) form a rectangular movement track.

2. The prism lens defect detection and sorting device based on machine vision according to claim 1, characterized in that The support groove (23) includes a V-shaped support groove (231), and two tops of the V-shaped support groove (231) are horizontally extended outwards with support steps (232). The included angle of the V-shaped support groove (231) is 60 degrees to support a triangular prism lens with its edge facing down, and the total width of the support steps (232) is adapted to the width of the cylindrical surface of the triangular prism lens to support a triangular prism lens with its cylindrical surface facing down.

3. The prism lens defect detection and sorting device based on machine vision according to claim 2, characterized in that, The handling grooves include a number of shallow trapezoidal grooves (221) for translating and stepping and transporting a triangular prism lens with its cylindrical surface facing down, three deep V-shaped grooves (222) for flipping and stepping and transporting a triangular prism lens with its cylindrical surface facing down, and three deep trapezoidal grooves (223) for flipping and stepping and transporting a triangular prism lens with its edge facing down. The shallow trapezoidal grooves (221) and the deep V-shaped grooves (222) are alternately arranged in the detection area below the camera component (24).

4. The prism lens defect detection and sorting device based on machine vision according to claim 3, characterized in that, In the rising state of the stepping fork (22), the included angle of the deep V-shaped groove (222) is 60 degrees and its left vertex is located in the left half of the upper support groove (23) above it, and the bottom endpoint of the left waist of the deep trapezoidal groove (223) is aligned with the midline of the upper support groove (23) above it; the waist sides of the support steps (232) and the waist sides of the deep trapezoidal grooves (223) are both at an angle of 60 degrees with the vertical direction.

5. The prism lens defect detection and sorting device based on machine vision according to claim 4, characterized in that When the stepping fork (22) is in the position of the descending action, each of the handling grooves and each support groove (23) are aligned one by one in the vertical direction. The distance between the deep V-shaped groove (222), the deep trapezoidal groove (223) and the adjacent handling groove on their left is the sum of p and a, and the distance of the rest part is p; where p is the movement step distance of the stepping fork (22), and a is half of the width of the cylindrical surface of the triangular prism lens.

6. The prism lens defect detection and sorting device based on machine vision according to claim 1, characterized in that The sorting component (4) includes a telescopic mechanism (41) arranged on one side of the detection table (21) and a push plate (42) fixed to its telescopic end. A defective product box (43) is oppositely arranged on the other side of the detection table (21).

7. The prism lens defect detection and sorting device based on machine vision according to claim 1, characterized in that, Both the feeding component (1) and the discharging component (3) adopt conveyor belts.

8. The prism lens defect detection and sorting device based on machine vision according to claim 1, characterized in that Flexible pads are provided on the surfaces of both the support groove 23 and the handling groove.

Images