A machine vision-based triangular prism lens flaw detection and sorting device

Abstract

The present application relates to the technical field of lens production, and more particularly to a three-prism lens flaw detection and sorting device based on machine vision. The step-by-step conveying operation realizes the conveying of the three-prism lens, and compared with the continuous conveying mode, the static detection of the three-prism lens can be realized, and the detection accuracy is improved. Through the improvement of the support groove and the conveying groove of the step-by-step conveying mechanism, the three-prism lens can be turned over multiple times in the step-by-step conveying process, and the high-cost overturning manipulator or the complex overturning mechanism is not needed, so that the omnibearing detection of the three-prism lens can be completed, the time cost of the overturning operation is saved, and the efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lens production, and particularly relates to a three-prism lens flaw detection and sorting device based on machine vision. BACKGROUND

[0002] The three-prism lens is widely used in various optical instruments such as spectrometers and monochromators, and has high quality requirements. The appearance flaws of the processed three-prism lens need to be detected, including the flaw detection of the edges and the surfaces.

[0003] However, manual detection has problems such as high labor intensity and unguaranteed precision, and online detection needs to set up complex mechanical structures to flip the three-prism lens for all-around detection, such as multi-degree-of-freedom manipulators, which not only has high cost but also leads to low detection efficiency due to the time consumed by the flipping operation. In addition, online detection is mostly dynamic detection, and the detection precision is difficult to meet the high quality requirements of the three-prism lens.

[0004] Therefore, the technical personnel in the field are committed to developing a three-prism lens flaw detection and sorting device based on machine vision, which has simple structure, low cost, high efficiency and high precision. SUMMARY

[0005] In view of the above defects of the prior art, the technical problem to be solved by the present application is to provide a three-prism lens flaw detection and sorting device based on machine vision, which has simple structure, low cost, high efficiency and high precision.

[0006] To achieve the above-mentioned purpose, the present application provides a three-prism lens flaw detection and sorting device based on machine vision, which comprises a feeding assembly, a detection assembly, a discharging assembly and a sorting assembly for removing defective products arranged at the end of the detection assembly in sequence along the conveying direction.

[0007] A detection table is provided, and a plurality of transversely arranged support grooves are formed in the top surface of the detection table, which are used to support the three-prism lens with the edges downward or the surfaces downward.

[0008] A pair of step shift forks are symmetrically arranged on both sides of the detection table, and a plurality of carrying grooves are arranged on the step shift forks, which are used to step and carry the three-prism lens in each support groove.

[0009] A camera assembly is used to collect the images of the three-prism lens to detect the appearance flaws of the edges and the surfaces.

[0010] A driving mechanism is arranged to drive the lifting or horizontal advancing and retreating of the pair of step yokes synchronously, so that the step yokes form a rectangular motion track.

[0011] Further, the support groove comprises a V-shaped support groove, two top portions of the V-shaped support groove horizontally extend outwardly with support steps, and the included angle of the V-shaped support groove is 60 degrees for supporting the three-prism lens with the edge downward, and the total width of the support steps is adapted to the cylindrical width of the three-prism lens for supporting the three-prism lens with the cylindrical surface downward.

[0012] Further, the carrying groove comprises a plurality of shallow trapezoidal grooves for carrying the three-prism lens with the cylindrical surface downward in a translational step-by-step manner, three deep V-shaped grooves for carrying the three-prism lens with the cylindrical surface downward in a turnover step-by-step manner, and three deep trapezoidal grooves for carrying the three-prism lens with the edge downward in a turnover step-by-step manner, and the shallow trapezoidal grooves and the deep V-shaped grooves are alternately arranged in the detection area below the camera assembly.

[0013] Further, in the raised state of the step yoke, the included angle of the deep V-shaped groove is 60 degrees, and the left vertex thereof is located at the left half of the upper support groove, and the left waist end point of the deep trapezoidal groove is aligned with the middle line of the upper support groove; the waist edge of the support step and the waist edge of the deep trapezoidal groove are both 60 degrees with the vertical direction.

[0014] Further, when the step yoke is in the position of the descending action, each of the carrying grooves and each of the support grooves are vertically corresponding and aligned, the spacing between the deep V-shaped groove, the deep trapezoidal groove and the adjacent carrying groove on the left thereof is the sum of p and a, and the spacing of the remaining part is p; wherein, p is the motion step distance of the step yoke, and a is half of the cylindrical width of the three-prism lens.

[0015] Further, the sorting assembly comprises a telescopic mechanism arranged on one side of the detection table and a push plate fixed to the telescopic end of the telescopic mechanism, and a substandard product box is arranged on the other side of the detection table.

[0016] Further, the feeding assembly and the discharging assembly both adopt a conveying belt.

[0017] Further, the surfaces of the support grooves and the carrying grooves are both provided with flexible pads.

[0018] Compared with the prior art, the present application has the following beneficial effects:

[0019] The application realizes the conveying of the three-prism lens through the step-by-step conveying operation, and compared with the continuous conveying mode, the static detection of the three-prism lens can be realized, and the detection precision is improved. Through the improvement of the supporting groove and the conveying groove of the step-by-step conveying mechanism, the three-prism lens is turned over multiple times in the step-by-step conveying process, and the omnibearing detection of the three-prism lens can be completed without configuring the high-cost overturning manipulator or the complex overturning mechanism, while the time cost of the overturning operation is saved, and the efficiency is improved. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is the overall structure schematic diagram of the application;

[0021] Figure 2 is the structure schematic diagram of the detection assembly;

[0022] Figure 3 is Figure 2 the enlarged view at A in FIG.

[0023] Figure 4 is the overturning process schematic diagram of the three-prism lens;

[0024] Figure 5 is the position relationship schematic diagram of the supporting groove and the conveying groove;

[0025] Figure 6 is the step-by-step conveying process schematic diagram of the three-prism lens.

[0026] REFERENCE SIGNS:

[0027] 1, feeding assembly; 2, detection assembly; 21, detection table; 22, step-by-step fork; 23, supporting groove; 24, camera assembly; 221, shallow trapezoidal groove; 222, deep V-shaped groove; 223, deep trapezoidal groove; 231, V-shaped supporting groove; 232, supporting step; 3, discharging assembly; 4, sorting assembly; 41, telescopic mechanism; 42, push plate; 43, defective product box. DETAILED DESCRIPTION

[0028] The following reference description of the drawings introduces the plurality of preferred embodiments of the application, so that the technical content thereof is more clear and convenient to understand. The application can be embodied in many different forms of embodiments, and the protection scope of the application is not limited to the embodiments mentioned herein.

[0029] In the drawings, the components with the same structure are denoted by the same reference numerals, and the components with similar structure or function are denoted by similar reference numerals. The size and thickness of each component shown in the drawings are arbitrarily shown, and the size and thickness of each component are not limited by the application. In order to make the drawing clearer, the thickness of some components is appropriately exaggerated in some places in the drawings.

[0030] REFERENCE Figure 1The present invention provides a machine vision-based defect detection and sorting device for triangular prism lenses, comprising a feeding assembly 1, a detection assembly 2, and a discharging assembly 3 arranged sequentially along the conveying direction, and a sorting assembly 4 disposed at the end of the detection assembly for rejecting defective products; the detection assembly includes:

[0031] The testing table 21 has several horizontally arranged support grooves 23 on its top surface. The support grooves 23 are used to support triangular prism lenses with their edges facing down or their cylindrical surfaces facing down.

[0032] A pair of stepping forks 22 are symmetrically arranged on both sides of the detection stage 21. Each stepping fork 22 is provided with a plurality of transport grooves, which are used to perform stepping transport of the triangular prism lens on each of the support grooves.

[0033] Camera assembly 24 is used to acquire images of the prism lens to detect appearance defects on its edges and cylindrical surfaces;

[0034] A drive mechanism is used to drive the pair of stepping forks 22 to move up and down or move forward and backward in a synchronized manner, so that the stepping forks 22 form a rectangular motion trajectory.

[0035] The drive mechanism (not shown in the figure) can be a combination of vertical linear modules and horizontal linear modules, or a cam-type stepper drive, etc. These are common drive designs in the mechanical field and will not be elaborated here.

[0036] With the above settings, the stepping fork 22 with a rectangular motion trajectory can lift the triangular prism lens in the support slot 23, advance one step, and then lower it to place the lifted triangular prism lens into the next support slot 23, realizing the stepping transport of the triangular prism lens. During this process, the camera component 24 coordinates with the stepping rhythm to perform image acquisition and detection of the triangular prism lens in the support slot 23 below. This detection process is actually a static visual detection, which can effectively improve image quality and thus improve detection accuracy compared with the detection under continuous transport mode.

[0037] Based on the purpose of inspecting all three edges and three cylindrical surfaces of the triangular prism lens, the above technical solution is further improved to enable the triangular prism lens to flip during the step-by-step transport process and be supported in the support groove in different postures; specifically, the triangular prism lens is flipped 60 degrees during each step-by-step transport, and through six transports, its three edges and three cylindrical surfaces are arranged to face the upward camera assembly 24 in an alternating manner for comprehensive visual inspection.

[0038] Further, see Figures 2-3The support groove 23 comprises a V-shaped support groove 231, two top parts of the V-shaped support groove 231 horizontally expand outwardly with support steps 232, the included angle of the V-shaped support groove 231 is 60 degrees for supporting the three-prism lens with the edge downward, and the total width of the support steps 232 is adapted to the cylindrical width of the three-prism lens for supporting the three-prism lens with the cylindrical downward.

[0039] Through the above setting, each support groove 23 can be used to support three-prism lenses in different postures, improving the applicability of the support groove 23. Of course, since the posture of the three-prism lens supported by each support groove 23 is certain, each support groove 23 can also be only a V-shaped support groove 231 or only a support step 232.

[0040] Further, referring to Figures 2-4 The carrying groove comprises a plurality of shallow trapezoidal grooves 221 for translational step-by-step carrying of the three-prism lens with the cylindrical downward, three deep V-shaped grooves 222 for overturning step-by-step carrying of the three-prism lens with the cylindrical downward, and three deep trapezoidal grooves 223 for overturning step-by-step carrying of the three-prism lens with the edge downward, the shallow trapezoidal grooves 221 and the deep V-shaped grooves 222 are alternately arranged below the detection area of the camera assembly 24.

[0041] Further, in the raised state of the step-by-step fork 22, the included angle of the deep V-shaped groove 222 is 60 degrees, and the left vertex thereof is located in the left half of the upper support groove 23, the left waist bottom end point of the deep trapezoidal groove 223 is aligned with the middle line of the upper support groove 23; the waist edge of the support step 232 and the waist edge of the deep trapezoidal groove 223 are both 60 degrees with the vertical direction.

[0042] Combined with Figure 4 The overturning principles of the deep V-shaped groove 222 and the deep trapezoidal groove 223 are explained, Figure 4 The rectangular arrow frames on the left side of the figure illustrate the rectangular motion trajectory of the step-by-step fork 22, and the black dots illustrate the positions of the step-by-step fork 22 in the motion trajectory in the corresponding state. Specifically:

[0043] In state a, the step-by-step fork 22 is ready to rise;

[0044] In states b-c, the step-by-step fork 22 is in the process of rising, since the left vertex of the deep V-shaped groove 222 is located in the left half of the downward cylindrical of the corresponding three-prism lens, the three-prism lens is pushed to overturn with the right edge as the rotation axis; since the left waist bottom end point of the deep trapezoidal groove 223 is aligned with the lower edge of the three-prism lens above, the deep trapezoidal groove 223 lifts the three-prism lens with the edge downward and maintains the posture of the three-prism lens in the process of rising;

[0045] In the d state, the stepping fork 22 has completed the lifting action, the triangular prism lens above the deep V-shaped groove 222 has completed the 60-degree overturning and is fully supported in the deep V-shaped groove 222 with the edge downward; the triangular prism lens in the deep trapezoidal groove 223 in the “inverted” state is in an unstable state that is easy to overturn 60 degrees clockwise, and in most cases, no other operation is needed to complete the overturning.

[0046] In the e state, the stepping fork 22 has completed the right movement, and the triangular prism lenses in the deep V-shaped groove 222 and the deep trapezoidal groove 223 are aligned with the support groove 23 below, so as to unload the triangular prism lenses in the support groove 23 when the stepping fork 22 is lowered. Among them, if the triangular prism lens in the deep trapezoidal groove 223 in the “inverted” state fails to complete the overturning due to its instability in the d state, then in the e state, the inertia of the stepping fork 22 when completing the right movement and “braking” will also cause the triangular prism lens to complete the overturning due to its instability.

[0047] Further, referring to Figures 5-6 When the stepping fork 22 is in the position of the lowering action, each of the carrying grooves is vertically aligned with each of the support grooves 23, the spacing between the deep V-shaped groove 222, the deep trapezoidal groove 223 and the adjacent carrying groove to the left is the sum of p and a, and the spacing of the rest is p; wherein p is the movement step of the stepping fork 22, and a is half of the width of the cylindrical surface of the triangular prism lens.

[0048] Based on the overturning principle of the deep V-shaped groove 222 and the deep trapezoidal groove 223, it can be known that the triangular prism lens itself moves forward by a distance a during the overturning process, that is, in addition to the carrying step p, the triangular prism lens itself moves forward by a distance a during the overturning process in the carrying groove spacing with the overturning action.

[0049] Referring to Figure 6 which shows the action cooperation process between the entire detection table 21 and the stepping fork 22. Figure 6 The rectangular arrow frame on the left side of the middle shows the rectangular motion trajectory of the stepping fork 22, and the black dot shows the position of the stepping fork 22 in the motion trajectory in the corresponding state.

[0050] Further, the sorting assembly 4 includes a telescopic mechanism 41 arranged on one side of the detection table 21 and a push plate 42 fixed to the telescopic end of the telescopic mechanism 41, and a defective product box 43 is arranged on the other side of the detection table 21.

[0051] When the triangular prism lens with defects after detection is carried to the support groove 23 corresponding to the sorting assembly 4, the telescopic mechanism 41 drives the push plate 42 to push the defective product into the defective product box 43; the qualified product at this position is carried to the discharge assembly 3 by the end carrying groove of the stepping fork 22.

[0052] Further, the feeding assembly 1 and the discharging assembly 3 are both provided with a conveyor belt.

[0053] Further, the surface of the supporting groove 23 and the carrying groove are both provided with a flexible pad, such as rubber, thin sponge, etc., to prevent damage to the triangular prism lens.

[0054] The preferred embodiments of the present application have been described in detail. It should be understood that modifications and variations can be made by those skilled in the art without creating spurious equivalents to fall within the scope of the present application. Therefore, any technical solutions obtained by logical analysis, reasoning or limited experiments based on the concept of the present application in the prior art should be within the protection scope defined by the claims.

Claims

1. A machine vision-based defect detection and sorting device for triangular prism lenses, characterized in that, It includes a feeding assembly (1), a detection assembly (2), and a discharging assembly (3) arranged sequentially along the conveying direction, and a sorting assembly (4) for rejecting defective products located at the end of the detection assembly; the detection assembly includes: The top surface of the testing table (21) is provided with several horizontally arranged support grooves (23), which are used to support the triangular prism lens with its edges facing down or its cylindrical surface facing down. A pair of stepping forks (22) are symmetrically arranged on both sides of the detection table (21). The stepping forks (22) are provided with a number of transport grooves, which are used to carry out stepping transport of the triangular prism lenses on each of the support grooves. Camera assembly (24) is used to acquire images of the prism lens for appearance defect detection of its edges and cylindrical surfaces; A drive mechanism is used to drive the pair of stepping forks (22) to move up and down or move forward and backward in a synchronized manner, so that the stepping forks (22) form a rectangular motion trajectory. The support groove (23) includes a V-shaped support groove (231), and the two tops of the V-shaped support groove (231) extend horizontally outward with support steps (232). The included angle of the V-shaped support groove (231) is 60 degrees to support the triangular prism lens with the edge facing down. The total width of the support steps (232) is adapted to the width of the cylindrical surface of the triangular prism lens to support the triangular prism lens with the cylindrical surface facing down. The transport groove includes several shallow trapezoidal grooves (221) for translating and transporting triangular prism lenses with the cylindrical surface facing down, three deep V-shaped grooves (222) for flipping and transporting triangular prism lenses with the cylindrical surface facing down, and three deep trapezoidal grooves (223) for flipping and transporting triangular prism lenses with the edges facing down. The shallow trapezoidal grooves (221) and deep V-shaped grooves (222) are alternately arranged in the detection area below the camera assembly (24).

2. The machine vision-based triangular prism lens defect detection and sorting device as described in claim 1, characterized in that, In the ascending state of the stepping fork (22), the deep V-shaped groove (222) has an included angle of 60 degrees and its left vertex is located on the left half of the support groove (23) above it; the left waist bottom end of the deep trapezoidal groove (223) is aligned with the center line of the support groove (23) above it; the waist of the support step (232), the waist of the deep trapezoidal groove (223) and the vertical direction are all at an angle of 60 degrees.

3. The machine vision-based triangular prism lens defect detection and sorting device as described in claim 2, characterized in that, When the stepping fork (22) is in the descending position, each of the transport grooves and each of the support grooves (23) are aligned vertically. The distance between the deep V-shaped groove (222), the deep trapezoidal groove (223) and the transport groove to its left is the sum of p and a, and the distance of the remaining parts is p; where p is the movement step distance of the stepping fork (22) and a is half the width of the cylindrical surface of the triangular prism lens.

4. The machine vision-based triangular prism lens defect detection and sorting device as described in claim 1, characterized in that, The sorting component (4) includes a telescopic mechanism (41) disposed on one side of the inspection table (21) and a push plate (42) fixed to its telescopic end. A defective box (43) is disposed opposite to the other side of the inspection table (21).

5. The machine vision-based triangular prism lens defect detection and sorting device as described in claim 1, characterized in that, Both the feeding assembly (1) and the discharging assembly (3) are conveyor belts.

6. The machine vision-based triangular prism lens defect detection and sorting device as described in claim 1, characterized in that, Both the support groove 23 and the transport groove are provided with flexible pads on their surfaces.

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